Robert,
I just want to toss my two cents worth in about the original subject of contour on the bottom of lasts. Unless I misread one of your earlier comments, you seemed to be saying that you don’t think the last should have contour on the bottom, at least not concave contour, but rather convex contour if anything at all. I’m certainly not a doctor or C. Ped., but I don’t understand why concave contour would not be a good thing, considering the shape of the foot. And when I talk about contour on the bottom of a last I mean in “realistic” proportions. Like everything else our society takes to extremes, you really CAN have too much of a good thing. I’ve made a lot of lasts with concave contoured bottoms, many with extra depth added to allow for post applied insoles in manufacturing or orthotics prescribed to the wearer and as far as I know the results have been well received.
I’ve also made quite a few lasts with a convex concave ranging in size from around a quarter to well over a half dollar for metatarsal pads. Even some production lasts have these features built in....at least some older lasts did. I know from personal experience and from listening to my wife’s many sermons on the subject before I came over to the “dark side” that one of the most comfortable, if not stylish (sorry Juel), pairs of footwear you can have on is a pair of Birkenstock sandals, clogs, or even their God awful, ugly closed toe shoes. The very comfortable cork bottoms are ever so slightly concave in the heel and ball areas and the sides definitely curve up rather than drastically intersect the bottom. And they get more contoured as your feet mold the cork to their shape. Plus they generally have very nice arch support. Too bad they all look like deformed ping pong paddles but then I’ve never seen a really attractive pair of feet (with apologies to those ladies who model shoes for a living....I’m really looking at the shoes, not your feet).
Once, when I worked for JV during the contour bottom craze of the 80s, we even made a last for a production shoe manufacturer that was completely CONVEX on the bottom. You could lay a straight edge across the bottom and see various gaps of daylight from end to end. Notice I said we made “a” last like this, not “some”. This was for a casual or dress style (memory fails me) but I don’t think it ever went to production and I’m not sure if it made it to fit trials. The theory was to allow for a fully cushioned bottom that would “rise up and embrace the feet”. I think we always called those house slippers but the customer was always “right” when I worked in that segment of the industry and it wasn’t my customer anyway.
If I misunderstood your position on contours, please explain or feel free to rebut me if we do indeed disagree on this. This is, unfortunately, not a perfect science and I keep an open mind.
Bill “The Last Man Standing” Tippit
www.globalfootwearsolutions.com
One "Last" Question
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jenny_fleishman
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Re: One "Last" Question
Robert,
Thanks! A few more questions, if you'll humor me.
How do you heat mold PZ? I don't have any special equipment. Can it be done in a regular oven?
What do you think of white PZ as an alternative?
At what point do you add a metatarsal pad to an orthotic, and can you judge the proper location from the plaster cast of the foot?
Jenny
(Thought I posted this earlier, but it didn't seem to appear, so apologies if it appears twice.)
Thanks! A few more questions, if you'll humor me.
How do you heat mold PZ? I don't have any special equipment. Can it be done in a regular oven?
What do you think of white PZ as an alternative?
At what point do you add a metatarsal pad to an orthotic, and can you judge the proper location from the plaster cast of the foot?
Jenny
(Thought I posted this earlier, but it didn't seem to appear, so apologies if it appears twice.)
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relferink
Re: One "Last" Question
Bill,
Thanks for your input. You, more than any of us have been exposed to the different types of lasts that various clients have dreamed up. First of all, too much of a good thing turns bad very fast, everything in moderation. I agree fully with that.
It not so much that I don’t think that the last should not have a concave contour, I just don’t see any specific reason in the mechanics and function of the foot that would require that shape or even benefit from that shape. I think I mentioned somewhere that the convex contour at the ball is something very few people can tolerate; a convex accommodation like a met pad behind the ball does get accepted by most customers. (except the most delicate feet like DW’s
)
With new manufacturing techniques like injection molding the reason for the concave contour to accommodate the welt or the upper leather folded over is no longer there.
When you consider the shape of the foot you see your feet out of a shoe hanging in the air, the concave contour of the ball area is caused by the fat pad and other soft tissue more than the bone structure. There are plenty of people with a concave shape metatarsal area but that is due to the collapse of the transverse arch.
That said I have no problem with a last with a convex bottom, it obvious has a place in the world of shoemakers but I do not see an anatomical reason for it as the question was posted.
A very popular comfort shoe brand out of San Antonio makes a walking shoe that is lasted on a last without this convex. I have never seen their lasts but have taken apart enough of their shoes to know that it is nearly flat if not totally flat and it works very well for them.
The other issue is that it is nearly impossible to make shoes on a last with a convex bottom. How do you ensure contact between the last and the insole and even if you can do that, the product will most like not be very consistent in fit.
The concave shape of the heel on the other hand is a good thing, taking the pressure of the center of the heel and distributing it more around the whole heel. One of the reason some of those German shoes like Birkenstock but also Finn Comfort are so comfortable, they are not made to a classic “last shape” but to the “foot shape”. Put a Birkenstock next to a pair of Allen Admonds and you see what I mean by last vs foot shape.
You hit the nail in the head here, the “unattractive” shape of the foot is made more appealing by the shoe. The shape of the shoe is mandated by the shape of the last and as long as there is a way to squeeze the foot in the shoe many people will put up with it.
If only it were a perfect science, wouldn’t that be easy? It’s as much an art as a science and every body is shaped a little different and what works for one may not work for the next.
Jenny,
Glad to see you still with the program, others would have given up a long time ago. Good for you.
Heat molding PZ, all you need is heat, from a heat gun, I’ve seen hair dryers used (partially block the air intake in the back so the air that comes through get hotter than originally intended. Careful you my burn out the hair dryer) or an oven. I would not use your kitchen oven if I could help it since when you heat this type of stuff some chemicals could “leak” and if you burn it you would never want to use that over for food again. A cheap toaster oven is easy to get for this purpose. White PZ is a little firmer and would hold up better but I would still prefer an EVA like could. PZ will collapse over time, EVA has a better resistance to that.
When I make an orthotic of a plaster cast I grind down the mold of the foot where the met pad will be before anything gets fabricated. On a good mold you should be able to identify the metatarsal heads, that’s your bench mark. (a little experience in this won’t hurt but the only way to learn is hands on) I’ll get some screen shots together from the contractor I work for that does all this stuff in CAD-CAM. Personally I’m just as happy with the plaster manufacturing method.
Here’s a screen shot from of where I would put the met pad. Sorry it’s a little big but can not trim it right her and it shows the details well.
On the picture of the bottom of the foot you can see the tendon at the medial side, the metatarsal heads. This is as wide as I would go. It’s 3.5 mm high and the window on the right top shows the shape. Higher in the front, tapered to the back. The right side of the image is the front at the met heads.
Rob
Thanks for your input. You, more than any of us have been exposed to the different types of lasts that various clients have dreamed up. First of all, too much of a good thing turns bad very fast, everything in moderation. I agree fully with that.
It not so much that I don’t think that the last should not have a concave contour, I just don’t see any specific reason in the mechanics and function of the foot that would require that shape or even benefit from that shape. I think I mentioned somewhere that the convex contour at the ball is something very few people can tolerate; a convex accommodation like a met pad behind the ball does get accepted by most customers. (except the most delicate feet like DW’s
) With new manufacturing techniques like injection molding the reason for the concave contour to accommodate the welt or the upper leather folded over is no longer there.
When you consider the shape of the foot you see your feet out of a shoe hanging in the air, the concave contour of the ball area is caused by the fat pad and other soft tissue more than the bone structure. There are plenty of people with a concave shape metatarsal area but that is due to the collapse of the transverse arch.
That said I have no problem with a last with a convex bottom, it obvious has a place in the world of shoemakers but I do not see an anatomical reason for it as the question was posted.
A very popular comfort shoe brand out of San Antonio makes a walking shoe that is lasted on a last without this convex. I have never seen their lasts but have taken apart enough of their shoes to know that it is nearly flat if not totally flat and it works very well for them.
The other issue is that it is nearly impossible to make shoes on a last with a convex bottom. How do you ensure contact between the last and the insole and even if you can do that, the product will most like not be very consistent in fit.
The concave shape of the heel on the other hand is a good thing, taking the pressure of the center of the heel and distributing it more around the whole heel. One of the reason some of those German shoes like Birkenstock but also Finn Comfort are so comfortable, they are not made to a classic “last shape” but to the “foot shape”. Put a Birkenstock next to a pair of Allen Admonds and you see what I mean by last vs foot shape.
You hit the nail in the head here, the “unattractive” shape of the foot is made more appealing by the shoe. The shape of the shoe is mandated by the shape of the last and as long as there is a way to squeeze the foot in the shoe many people will put up with it.
If only it were a perfect science, wouldn’t that be easy? It’s as much an art as a science and every body is shaped a little different and what works for one may not work for the next.
Jenny,
Glad to see you still with the program, others would have given up a long time ago. Good for you.
Heat molding PZ, all you need is heat, from a heat gun, I’ve seen hair dryers used (partially block the air intake in the back so the air that comes through get hotter than originally intended. Careful you my burn out the hair dryer) or an oven. I would not use your kitchen oven if I could help it since when you heat this type of stuff some chemicals could “leak” and if you burn it you would never want to use that over for food again. A cheap toaster oven is easy to get for this purpose. White PZ is a little firmer and would hold up better but I would still prefer an EVA like could. PZ will collapse over time, EVA has a better resistance to that.
When I make an orthotic of a plaster cast I grind down the mold of the foot where the met pad will be before anything gets fabricated. On a good mold you should be able to identify the metatarsal heads, that’s your bench mark. (a little experience in this won’t hurt but the only way to learn is hands on) I’ll get some screen shots together from the contractor I work for that does all this stuff in CAD-CAM. Personally I’m just as happy with the plaster manufacturing method.
Here’s a screen shot from of where I would put the met pad. Sorry it’s a little big but can not trim it right her and it shows the details well.
On the picture of the bottom of the foot you can see the tendon at the medial side, the metatarsal heads. This is as wide as I would go. It’s 3.5 mm high and the window on the right top shows the shape. Higher in the front, tapered to the back. The right side of the image is the front at the met heads.
Rob
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jenny_fleishman
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Re: One "Last" Question
Robert, would any old toaster oven do, or does it need to go to a certain temperature? Do you fill in the metatarsal pad area with an extra piece of cloud, or put a poron pad in it? Do you fill in the arch area with extra layers of cloud? I feel like a kid in a candy store!
re vocabulary...mine is primitive. Is the medial tendon the one to the big toe joint? I've been looking on the Internet for a good diagram or illustration of the foot, and haven't found a comprehensive one yet. Thanks.
re vocabulary...mine is primitive. Is the medial tendon the one to the big toe joint? I've been looking on the Internet for a good diagram or illustration of the foot, and haven't found a comprehensive one yet. Thanks.
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relferink
Re: One "Last" Question
Jenny, a toaster oven would do just fine as long as the material is not to thick, 1/4” should work fine, once you get to thicker materials a convection oven would heat more evenly. As for as the temperature, I set my oven generally around 250 to 300 but don’t leave it in very long. Black smoke means it a little too well done, it’s really just like cooking. 
That’s probably why I’m not allowed in the kitchen.
Just don’t leave it in to long, it’s better to take it out early and put it back if it’s not playable enough. Depending on what the metatarsal pad is for I use a soft foam like Poron or a firmer material like Cloud. When the material is softer I usually go proportionately thicker on the met pad. The best way is to fill in the void for the metatarsal pad with some cloud or cork, when I use foam I place it after the orthotic is molded.
The medial tendon I so vaguely referred to is indeed the flexor hallucis longus tendon. I should have been more specific, as to some clear illustrations they may be hard to find. There are layers of tissue, muscles and tendons before you get to the skeleton. This picture shows the track of the , just not very well how it runs at the bottom of the foot.
Don’t have any others to offer from the top of my head. I did mark the tendon on the image with red, the tendon runs further than that but this is the area I’m concerned about when I put in a met pad.
I won’t be on-line tomorrow so I won’t get to read and post till later in the week. It’s not that I try to ignore anyone.
Rob
That’s probably why I’m not allowed in the kitchen. Just don’t leave it in to long, it’s better to take it out early and put it back if it’s not playable enough. Depending on what the metatarsal pad is for I use a soft foam like Poron or a firmer material like Cloud. When the material is softer I usually go proportionately thicker on the met pad. The best way is to fill in the void for the metatarsal pad with some cloud or cork, when I use foam I place it after the orthotic is molded.
The medial tendon I so vaguely referred to is indeed the flexor hallucis longus tendon. I should have been more specific, as to some clear illustrations they may be hard to find. There are layers of tissue, muscles and tendons before you get to the skeleton. This picture shows the track of the , just not very well how it runs at the bottom of the foot.
Don’t have any others to offer from the top of my head. I did mark the tendon on the image with red, the tendon runs further than that but this is the area I’m concerned about when I put in a met pad.
I won’t be on-line tomorrow so I won’t get to read and post till later in the week. It’s not that I try to ignore anyone.
Rob
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dw
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Re: One "Last" Question
Well my head is swimming...I think we need to establish some terms here...being on the same page is always good:
A concave surface is one that recedes, a convex surface is one that bulges. Thus lasts with a bottom radius, such as we see on contemporary lasts, are convex. Lasts that have scooped out areas under the shank would be concave. Any appliance that lifts the foot, such as a met pad would be convex.
If one gets the terms mixed up (as I used to) think of "cave" or "cavity" and the issue will immediately clarify itself.
Tight Stitches
DWFII--Member HCC
A concave surface is one that recedes, a convex surface is one that bulges. Thus lasts with a bottom radius, such as we see on contemporary lasts, are convex. Lasts that have scooped out areas under the shank would be concave. Any appliance that lifts the foot, such as a met pad would be convex.
If one gets the terms mixed up (as I used to) think of "cave" or "cavity" and the issue will immediately clarify itself.
Tight Stitches
DWFII--Member HCC
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dw
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Re: One "Last" Question
Robert,
Good pics! Very enlightening. Thanks for that. Ya gotta love computers.
Tight Stitches
DWFII--Member HCC
Good pics! Very enlightening. Thanks for that. Ya gotta love computers.
Tight Stitches
DWFII--Member HCC
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jenny_fleishman
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Re: One "Last" Question
DW...re convex, concave...I guess I got it backwards because I was referring to the radius of the inside of the shoe being concave. Naturally the outside is the opposite!
Also, a clarification...when I was talking about the curve across the ball of the foot, I meant a curve all the way across, not just near the edge where the upper meets the sole.
Are there instructions somewhere on this site on how to post pictures? If/when I finish my lasts, I'd like to post a picture, unless they are a complete embarrassment!
Robert, thanks once again. Enjoy your "day off."
Jenny
Also, a clarification...when I was talking about the curve across the ball of the foot, I meant a curve all the way across, not just near the edge where the upper meets the sole.
Are there instructions somewhere on this site on how to post pictures? If/when I finish my lasts, I'd like to post a picture, unless they are a complete embarrassment!
Robert, thanks once again. Enjoy your "day off."
Jenny
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btippit
Re: One "Last" Question
DW,
Guilty as charged. When I said "concave" I was referring to contoured bottoms where the surface expanded like a balloon being blown up (literally sometimes). The one and only last I was ever involved in that had a completely sunken in bottom surface (like someone had scooped the bottom out like they were dishing out ice cream) was my "convex" reference, as were my references to the allowances for met pads. I suppose, like Jenny said, it was a subliminal reference to the shoe.
My dictionary refers to concave as "curved like the interior of a circle" and convex as "curved like the exterior of a circle". Then, in an absolute stroke of genius (tongue firmly planted in cheek), it shows an illustration of two half circles standing VERTICALLY so that you could really say either picture fits either descriptioin. So.....he said, playing "Devil's Advocate", I suppose it depends on what side of the circle you're on. I really need to stop buying factory defect dictionaries.
Now my head is swimming so I'm going to go clear it. I lucked out and got a 2 hour gig on a drive time radio show in St. Louis this afternoon. It's a show that deals with nothing serious and only attempts to have fun...sort of Howard Stern or Bob and Tom if they did their shows on valium with their mother's watching....very PG. So I need to practice not saying those 7 words or however many can't be said over the airways nowadays.
Jenny, on the left side of your forum page, click on "Formatting" and then scroll down to "Other Formatting" and click on "Images, Attachments, and Clipart" and you'll get the format for inserting pix.
Bill “The Last Man Standing” Tippit
www.globalfootwearsolutions.com
Guilty as charged. When I said "concave" I was referring to contoured bottoms where the surface expanded like a balloon being blown up (literally sometimes). The one and only last I was ever involved in that had a completely sunken in bottom surface (like someone had scooped the bottom out like they were dishing out ice cream) was my "convex" reference, as were my references to the allowances for met pads. I suppose, like Jenny said, it was a subliminal reference to the shoe.
My dictionary refers to concave as "curved like the interior of a circle" and convex as "curved like the exterior of a circle". Then, in an absolute stroke of genius (tongue firmly planted in cheek), it shows an illustration of two half circles standing VERTICALLY so that you could really say either picture fits either descriptioin. So.....he said, playing "Devil's Advocate", I suppose it depends on what side of the circle you're on. I really need to stop buying factory defect dictionaries.
Now my head is swimming so I'm going to go clear it. I lucked out and got a 2 hour gig on a drive time radio show in St. Louis this afternoon. It's a show that deals with nothing serious and only attempts to have fun...sort of Howard Stern or Bob and Tom if they did their shows on valium with their mother's watching....very PG. So I need to practice not saying those 7 words or however many can't be said over the airways nowadays.
Jenny, on the left side of your forum page, click on "Formatting" and then scroll down to "Other Formatting" and click on "Images, Attachments, and Clipart" and you'll get the format for inserting pix.
Bill “The Last Man Standing” Tippit
www.globalfootwearsolutions.com
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dw
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Re: One "Last" Question
Bill,
Apologies if I came off a bit pedantic. But this discussion is bordering on kind of technical. I wasn't sure I was reading things correctly and wondered if I was understanding at all. Sometimes just defining terms (you don't even have to be right as long as everybody agrees)can make all the difference in the world.
Your dictionary definition could very well apply to an insole, however...the footside surface being concave (after shaping to the bottom of the last) and convex on the streetside surface. BUT, after some wear, and the insole taking on the characteristic of a good footbed, even the foodside surface might have some convexities.
Arrhg!! I think I'll go take a nap...
Tight Stitches
DWFII--Member HCC
Apologies if I came off a bit pedantic. But this discussion is bordering on kind of technical. I wasn't sure I was reading things correctly and wondered if I was understanding at all. Sometimes just defining terms (you don't even have to be right as long as everybody agrees)can make all the difference in the world.
Your dictionary definition could very well apply to an insole, however...the footside surface being concave (after shaping to the bottom of the last) and convex on the streetside surface. BUT, after some wear, and the insole taking on the characteristic of a good footbed, even the foodside surface might have some convexities.
Arrhg!! I think I'll go take a nap...
Tight Stitches
DWFII--Member HCC
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jenny_fleishman
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Re: One "Last" Question
Duplicating lasts...has anyone ever duplicated a last by making a plaster cast of it?
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btippit
Re: One "Last" Question
DW,
No apologies necessary. I think we're all on the same page now. These types of discussions are very difficult in the slow motion world of postings while we're trying to do our jobs at the same time. We all need to take a month off and go to a nice quiet resort (with a high speed connection of course). Then we could do this in real time with facial expressions, arm (not hand) gestures, and adult beverages, the way these things are supposed to be talked about.
Bill
No apologies necessary. I think we're all on the same page now. These types of discussions are very difficult in the slow motion world of postings while we're trying to do our jobs at the same time. We all need to take a month off and go to a nice quiet resort (with a high speed connection of course). Then we could do this in real time with facial expressions, arm (not hand) gestures, and adult beverages, the way these things are supposed to be talked about.
Bill
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cmw
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Re: One "Last" Question
All
I was looking in on the group and liked reading what's been going on the last wk.
I was thinking of what Robert wrote about the cork. We make orthopaedic shoes that have as little cork as possible so as to retain the sleek factory or design look . A thin layer is enough for minor cases. Try to think of a 3 mm cork layer in the bottom of the shoes. you could even angle the edges so as to make the insole narrower and again retain a sleek look.
The cork is also a good way to make more of a cup for the heel to fit into. You can adjust it as need be after the shoe is finished.
I finally had the chance to make my own last and the rest of the shoe recently. The curve on the bottom of the last has always bothered me because of what has been said here. Apart from the slight varus correction the last are more flat( from the met. line forward) that usual. Wow they feel good.
If you are going to make a light weight shoe that is pegged up to the met. line and just glues forward from there on it, there is not that much need for a lot of room for pinning material. which leave very little cork filling.
Robert, it looks like you are doing well judging from the foot scanner.
CW
I was looking in on the group and liked reading what's been going on the last wk.
I was thinking of what Robert wrote about the cork. We make orthopaedic shoes that have as little cork as possible so as to retain the sleek factory or design look . A thin layer is enough for minor cases. Try to think of a 3 mm cork layer in the bottom of the shoes. you could even angle the edges so as to make the insole narrower and again retain a sleek look.
The cork is also a good way to make more of a cup for the heel to fit into. You can adjust it as need be after the shoe is finished.
I finally had the chance to make my own last and the rest of the shoe recently. The curve on the bottom of the last has always bothered me because of what has been said here. Apart from the slight varus correction the last are more flat( from the met. line forward) that usual. Wow they feel good.
If you are going to make a light weight shoe that is pegged up to the met. line and just glues forward from there on it, there is not that much need for a lot of room for pinning material. which leave very little cork filling.
Robert, it looks like you are doing well judging from the foot scanner.
CW
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relferink
Re: One "Last" Question
Bill,
I’m in on the resort deal. Sign me up! Any place without snow will do for me but a tropical beach would be nice. Are you still in the last business or is radio your new calling now. Was it a gig on lasts and last making? I’m still planning on having you make a pair of last for myself but it will have to wait till next year since I’m getting ready to go back home for the holidays and I won’t be back till January 6th. By than I’m sure there is all kinds of stuff to catch up and before everything gets back to normal.
DW,
Thanks for the clarification of terms and I have to admit that I did mix some things up. By the time I figured it out I could no longer edit my post. Just for clarification purposes I have the following question, not just to DW but to all: Does a last with a convex bottom surface create a shoe with a concave shaped insole (and a convex shaped outsole as per Jenny’s post)? I think it does and if I read Bill’s dictionary quote correct it seems to agree to that. I’m just curios if you all agree. English is only my second language so I’m very glad getting the additional clarifications.
Jenny,
I have some experience with copying lasts using plaster bandages. It’s not an easy process but is doable. In short you take the last you want to copy, wrap it with foil, try to keep wrinkles to a minimum. Then cast the last. Make it nice and thick. Thin areas may not show as long as the plaster is on the last but will give you a big headache later. When the plaster is set but still moist mark the instep with a bunch of lines and cut the model open. Do the same in the back.
You take the last out and line up the cuts in the plaster mold on the lines you made before. Now let it dry some more. Re-apply plaster bandages to close the cast up. Let this dry very, very good.
Depending on what last you will make you go on from her. A plaster last would be the easiest but it will be hard to make shoes on that, it’s too brittle. First you poor a soap solution in the mold, splash it around and discard of any access. Let it dry and fill the mold with plaster. If you want this is the time to add reinforcement, you could use some re-bar. After it dries peal off the plaster bandages. The soap you used provides a separation layer between the positive and the negative mold. If you want to use a material that you can make shoes on like Poly Urethane you have to insulate the mold with a silicone lining before pouring the last. There are some materials commercially available.
Chris,
Good to hear from you, haven’t seen you on the forum for some time. How are things?
Your right on keeping the cork to a minimum, all you want to do is even out he contours of the foot to the point where you have an even base to build the shoe around. Some are thinner than others, if a customer needs a lot of padding in selected areas I have to make up for that in other parts of the insert so cork would do that job. If a rocker bottom is required I add cork under the ball of the foot and taper it to the toe. Less is better from a cosmetic standpoint but as I have said before, functionality before fashion for my specific applications.
I agree with the flatter forefoot part of the last, it works well for most feet. How is the training coming along? Getting into the fitting room at all and see customers? How is the Danish course set up, is there an opportunity to specialize between a fitter who deals mostly with customers and a maker who deals with the production end? Something like that was being set up as I left school black in the Netherlands but I still got the “full package” educations.
The foot scanner is not something I own so I guess I’m not doing all that well….
In fact I think this scanner and software package is too expensive and too limiting in what it allows me to do compared to making a mold and modifying it by hand. Never the less it’s fun to get some CAD-CAM experience and learn to work with new “tools” like this. And off course it makes for some fancy pictures to post.
I’m very happy with the different jobs I have now, some I really enjoyed and others pay the bills. All and all a nice mix that keeps me sane.
Earlier this week I was invited to a factory tour at New Balance. Quite an interesting experience. The factory is not set up as a traditional assembly line but has what they call modular manufacturing. Small teams do a bunch of tasks in a highly automated production “pod”. Great to see that shoes are still made in the US. It is amazing for me to see that some of the shoes that they make spend only 2.5 minutes on the last. Compare that to what I do and like to leave the shoe on the last for a week or more if time permits. An other notable point, the lasts were much flatter (less convex) than production lasts that I have traditionally seen. Didn’t get to take pictures but had a behind the scenes tour of the R&D facility.
I think I’m mostly caught up for now. Have a great weekend,
Rob
I’m in on the resort deal. Sign me up! Any place without snow will do for me but a tropical beach would be nice. Are you still in the last business or is radio your new calling now. Was it a gig on lasts and last making? I’m still planning on having you make a pair of last for myself but it will have to wait till next year since I’m getting ready to go back home for the holidays and I won’t be back till January 6th. By than I’m sure there is all kinds of stuff to catch up and before everything gets back to normal.
DW,
Thanks for the clarification of terms and I have to admit that I did mix some things up. By the time I figured it out I could no longer edit my post. Just for clarification purposes I have the following question, not just to DW but to all: Does a last with a convex bottom surface create a shoe with a concave shaped insole (and a convex shaped outsole as per Jenny’s post)? I think it does and if I read Bill’s dictionary quote correct it seems to agree to that. I’m just curios if you all agree. English is only my second language so I’m very glad getting the additional clarifications.
Jenny,
I have some experience with copying lasts using plaster bandages. It’s not an easy process but is doable. In short you take the last you want to copy, wrap it with foil, try to keep wrinkles to a minimum. Then cast the last. Make it nice and thick. Thin areas may not show as long as the plaster is on the last but will give you a big headache later. When the plaster is set but still moist mark the instep with a bunch of lines and cut the model open. Do the same in the back.
You take the last out and line up the cuts in the plaster mold on the lines you made before. Now let it dry some more. Re-apply plaster bandages to close the cast up. Let this dry very, very good.
Depending on what last you will make you go on from her. A plaster last would be the easiest but it will be hard to make shoes on that, it’s too brittle. First you poor a soap solution in the mold, splash it around and discard of any access. Let it dry and fill the mold with plaster. If you want this is the time to add reinforcement, you could use some re-bar. After it dries peal off the plaster bandages. The soap you used provides a separation layer between the positive and the negative mold. If you want to use a material that you can make shoes on like Poly Urethane you have to insulate the mold with a silicone lining before pouring the last. There are some materials commercially available.
Chris,
Good to hear from you, haven’t seen you on the forum for some time. How are things?
Your right on keeping the cork to a minimum, all you want to do is even out he contours of the foot to the point where you have an even base to build the shoe around. Some are thinner than others, if a customer needs a lot of padding in selected areas I have to make up for that in other parts of the insert so cork would do that job. If a rocker bottom is required I add cork under the ball of the foot and taper it to the toe. Less is better from a cosmetic standpoint but as I have said before, functionality before fashion for my specific applications.
I agree with the flatter forefoot part of the last, it works well for most feet. How is the training coming along? Getting into the fitting room at all and see customers? How is the Danish course set up, is there an opportunity to specialize between a fitter who deals mostly with customers and a maker who deals with the production end? Something like that was being set up as I left school black in the Netherlands but I still got the “full package” educations.
The foot scanner is not something I own so I guess I’m not doing all that well….
In fact I think this scanner and software package is too expensive and too limiting in what it allows me to do compared to making a mold and modifying it by hand. Never the less it’s fun to get some CAD-CAM experience and learn to work with new “tools” like this. And off course it makes for some fancy pictures to post.
I’m very happy with the different jobs I have now, some I really enjoyed and others pay the bills. All and all a nice mix that keeps me sane.
Earlier this week I was invited to a factory tour at New Balance. Quite an interesting experience. The factory is not set up as a traditional assembly line but has what they call modular manufacturing. Small teams do a bunch of tasks in a highly automated production “pod”. Great to see that shoes are still made in the US. It is amazing for me to see that some of the shoes that they make spend only 2.5 minutes on the last. Compare that to what I do and like to leave the shoe on the last for a week or more if time permits. An other notable point, the lasts were much flatter (less convex) than production lasts that I have traditionally seen. Didn’t get to take pictures but had a behind the scenes tour of the R&D facility.
I think I’m mostly caught up for now. Have a great weekend,
Rob
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dw
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Re: One "Last" Question
Rob,
I suppose it would depend upon which surface is your point of reference. If we look at the lastside surface of the insole it is definately a concave surface created by shaping around a convex surface. If we look at the "pavement" side of the insole it is convex. And the same thing applies to the outsole. Of course the last itself is convex on the (dorsal?) insole side and both convex and concave on the (ventral?) upper surface...depends on your point of reference.
Tight Stitches
DWFII--Member HCC
I suppose it would depend upon which surface is your point of reference. If we look at the lastside surface of the insole it is definately a concave surface created by shaping around a convex surface. If we look at the "pavement" side of the insole it is convex. And the same thing applies to the outsole. Of course the last itself is convex on the (dorsal?) insole side and both convex and concave on the (ventral?) upper surface...depends on your point of reference.
Tight Stitches
DWFII--Member HCC
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cmw
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Re: One "Last" Question
Rob
It’s good that you are making ends meet, I know what you mean about the scanner. There is another master that works at the shop now. He has one and said that the old fashion way is easier. It can be hard to tell how much pressure is on one spot with the scanner. AND they do cost allot.
They apprenticeship is going somewhat ok. I’m tired of being under somebody else right now. First as a cobbler and now as a hand-shoemaker as they call it.
With regards to the separation of the parts of shoemaking , things have not changed here for yrs. and yrs.. Cobblers, hand-shoemaker, masters, designers and clickers/seamstress are the divisions of work and training. I am lucky that my master is willing to answer my question about all of the above. Jacob works 60 -70 hrs a wk and is there to help if I stay after work to make something for myself. It’s even better for me that he can do all of the above including lasts and will let me watch. The customers are another story though. Many are touchyyyy because of the problems
Part of me would like to work for myself and not think about the time issue as much. The sword group at the center is jumping up and down because I said there were problems with the orth. branch (county agreements and financing) and I might lose my job because of it. They want all sorts of things made.
My wife and the sofa calls.
Take care
CW
It’s good that you are making ends meet, I know what you mean about the scanner. There is another master that works at the shop now. He has one and said that the old fashion way is easier. It can be hard to tell how much pressure is on one spot with the scanner. AND they do cost allot.
They apprenticeship is going somewhat ok. I’m tired of being under somebody else right now. First as a cobbler and now as a hand-shoemaker as they call it.
With regards to the separation of the parts of shoemaking , things have not changed here for yrs. and yrs.. Cobblers, hand-shoemaker, masters, designers and clickers/seamstress are the divisions of work and training. I am lucky that my master is willing to answer my question about all of the above. Jacob works 60 -70 hrs a wk and is there to help if I stay after work to make something for myself. It’s even better for me that he can do all of the above including lasts and will let me watch. The customers are another story though. Many are touchyyyy because of the problems
Part of me would like to work for myself and not think about the time issue as much. The sword group at the center is jumping up and down because I said there were problems with the orth. branch (county agreements and financing) and I might lose my job because of it. They want all sorts of things made.
My wife and the sofa calls.
Take care
CW
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jenny_fleishman
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Re: One "Last" Question
Here's a picture of a trial last I made out of Liquid Last. It's a mixture of Bondo and polyester resin.I'd be happy to provide more details if anyone wants them.I got the recipe from a place that used to sell it.
Here's the last cut in two after drilling holes through it for lag bolts.
Here it is with cardboard cemented on to make up for the saw cut, and the lag bolts through the top section for demonstration purposes. One slight glitch. Even though I drilled the holes before cutting the last in two, when the bolts get to the second piece, they push the two pieces out of alignment. I have one possible solution to this, but open to suggestions!
re the Liquid Last mixture. I made a few samples about an inch thick in Dixie cups. Pounded a few tacks into one, and it took the tacks well. I'd be happy to mail a sample or two of the LL out if anyone wants to check it out.
Jenny
Here's the last cut in two after drilling holes through it for lag bolts.
Here it is with cardboard cemented on to make up for the saw cut, and the lag bolts through the top section for demonstration purposes. One slight glitch. Even though I drilled the holes before cutting the last in two, when the bolts get to the second piece, they push the two pieces out of alignment. I have one possible solution to this, but open to suggestions!
re the Liquid Last mixture. I made a few samples about an inch thick in Dixie cups. Pounded a few tacks into one, and it took the tacks well. I'd be happy to mail a sample or two of the LL out if anyone wants to check it out.
Jenny
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jenny_fleishman
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Re: One "Last" Question
Forgot to mention that I put blocks of wood inside the last molds for the bolts, but I think that's apparent from the pictures!
Jenny
Jenny
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Alasdair Muckart
Re: One "Last" Question
To get around the problem of the lag bolts pushing things out of alignment, I'd make sure the holes you drilled for them are only _just_ thick enough for the bolts, and thread them through before you cut the last in half. That way when the bolt cuts the thread into the wood it won't be able to displace things.
If you were feeling adventurous you could cast the last around engineering bolts with nuts on the end. If you oiled up the bolts you should be able to extract them before cutting the last in half and if the liquid last flows around the nut it'll hold it in place nicely and provide a good positive lock-up.
I don't have any cunning plans for how to repair the current situation though I'm sorry.
How did you generate the mould you cast the last into?
If you were feeling adventurous you could cast the last around engineering bolts with nuts on the end. If you oiled up the bolts you should be able to extract them before cutting the last in half and if the liquid last flows around the nut it'll hold it in place nicely and provide a good positive lock-up.
I don't have any cunning plans for how to repair the current situation though I'm sorry.
How did you generate the mould you cast the last into?
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btippit
Re: One "Last" Question
Jenny,
Very impressive! It's much smoother and more...well, "last shaped" than I was expecting, simply because I know how difficult it is to form something from nothing.
As for the lag bolts pushing things apart when they hit the second piece, I may have a solution. When you cut a wood model to adjust the heel height, swap toes, etc. you sometimes use screws to hold the wood together instead of just dowel rods. To keep the wood from separating you countersink the bit to a diameter close to the tip of the wood screw before it goes back to the threads. This allows the screw to bite into the second piece and be drawn into it instead of being repelled.
I'm assuming if you did the same thing with your drill bit, the lag bolts would grab the second piece instead of pushing it away. Here's a picture of the 5/16" bit I used to use for the wood models. It actually appears that I've used it for something else because normally, the countersink portion is even more narrow than this and longer. You need to grind the end of the bit very carefully, trying to keep it as balanced as possible.
I hope this helps. It might have been the solution you were talking about anyway.
Bill “The Last Man Standing” Tippit
www.globalfootwearsolutions.com
Very impressive! It's much smoother and more...well, "last shaped" than I was expecting, simply because I know how difficult it is to form something from nothing.
As for the lag bolts pushing things apart when they hit the second piece, I may have a solution. When you cut a wood model to adjust the heel height, swap toes, etc. you sometimes use screws to hold the wood together instead of just dowel rods. To keep the wood from separating you countersink the bit to a diameter close to the tip of the wood screw before it goes back to the threads. This allows the screw to bite into the second piece and be drawn into it instead of being repelled.
I'm assuming if you did the same thing with your drill bit, the lag bolts would grab the second piece instead of pushing it away. Here's a picture of the 5/16" bit I used to use for the wood models. It actually appears that I've used it for something else because normally, the countersink portion is even more narrow than this and longer. You need to grind the end of the bit very carefully, trying to keep it as balanced as possible.
I hope this helps. It might have been the solution you were talking about anyway.
Bill “The Last Man Standing” Tippit
www.globalfootwearsolutions.com
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jenny_fleishman
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Re: One "Last" Question
Thanks Alasdair. I actually had put the bolts in and taken them out before cutting the lasts, but still had the problem.
Are engineering bolts different than lag bolts, and do you think the block of wood would be unnecessary?
I wasn't planning to use this last anyway, so I'm not too put out by it, but still need to solve the problem for the "real" lasts!
Are engineering bolts different than lag bolts, and do you think the block of wood would be unnecessary?
I wasn't planning to use this last anyway, so I'm not too put out by it, but still need to solve the problem for the "real" lasts!
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Alasdair Muckart
Re: One "Last" Question
Hi Jenny,
Engineering bolts, at least here in NZ, are machine bolts where most of the shaft of the bolt is smooth, and only and inch or so of the end is threaded. More importantly the thread is usually cut into the shaft diameter, rather than the lands of the thread being a slightly wider diameter than the shaft as is common with screws.
There's a picture of one here:
http://www.istockphoto.com/file_thumbview_approve/421360/2/Nut_Bolt.jpg
From your pictures it looks like you've used something similar except that it has a screw thread which is cutting it's own thread into the wooden block. I've never built a last before, but from having tried solving similar problems it's that action which can push things out of alignment unless you get the point of the screw extremely accurately aligned and totally prevent it changing angle when you drive it in.
An engineering bolt/nut combination will have a tighter and more positive fit together and, if you cast around them, the fit-up of the two pieces would be exact once you'd cut them in half. This assumes of course that the liquid last won't stick to the bolt. It shouldn't if you oil the bolt, but there are no guarantees.
I'd love to get the recipie BTW, I think it might work nicely as a way to easily produce multiple identical forms for making leather jacks over.
Thanks.
Engineering bolts, at least here in NZ, are machine bolts where most of the shaft of the bolt is smooth, and only and inch or so of the end is threaded. More importantly the thread is usually cut into the shaft diameter, rather than the lands of the thread being a slightly wider diameter than the shaft as is common with screws.
There's a picture of one here:
http://www.istockphoto.com/file_thumbview_approve/421360/2/Nut_Bolt.jpg
From your pictures it looks like you've used something similar except that it has a screw thread which is cutting it's own thread into the wooden block. I've never built a last before, but from having tried solving similar problems it's that action which can push things out of alignment unless you get the point of the screw extremely accurately aligned and totally prevent it changing angle when you drive it in.
An engineering bolt/nut combination will have a tighter and more positive fit together and, if you cast around them, the fit-up of the two pieces would be exact once you'd cut them in half. This assumes of course that the liquid last won't stick to the bolt. It shouldn't if you oil the bolt, but there are no guarantees.
I'd love to get the recipie BTW, I think it might work nicely as a way to easily produce multiple identical forms for making leather jacks over.
Thanks.
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jenny_fleishman
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Re: One "Last" Question
Bill,
Thanks for the compliment and suggestion.
But you lost me here: "To keep the wood from separating you countersink the bit to a diameter close to the tip of the wood screw before it goes back to the threads. This allows the screw to bite into the second piece and be drawn into it instead of being repelled." I might need a diagram!
Jenny
Thanks for the compliment and suggestion.
But you lost me here: "To keep the wood from separating you countersink the bit to a diameter close to the tip of the wood screw before it goes back to the threads. This allows the screw to bite into the second piece and be drawn into it instead of being repelled." I might need a diagram!
Jenny
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dw
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Re: One "Last" Question
Not much time this morning...so if I missed someone else making the same suggestion, my apologies...
First you only need one lag bolt. If you were making a boot it would be a nightmare trying to get one bolt out of the last down inside the boot, much less two. Second you don't need so big a piece of wood. Third, as I recall from the times I did this (years ago) I screwed the bolt into the wood, greased the shaft of the bolt and cast it all together. Then when the plastic was set, I just backed the bolt out and cut the last. No drilling.
another 2¢ for the kitty
Tight Stitches
DWFII--HCC Member
First you only need one lag bolt. If you were making a boot it would be a nightmare trying to get one bolt out of the last down inside the boot, much less two. Second you don't need so big a piece of wood. Third, as I recall from the times I did this (years ago) I screwed the bolt into the wood, greased the shaft of the bolt and cast it all together. Then when the plastic was set, I just backed the bolt out and cut the last. No drilling.
another 2¢ for the kitty
Tight Stitches
DWFII--HCC Member
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jenny_fleishman
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Re: One "Last" Question
DW, questions...
I used 2 bolts because I was concerned the two pieces could twist out of alignment (pivot around the one bolt) if I only used one. From your experience, this doesn't happen?
Also, I did drill and put the bolts in and out of the last before I cut the last in two. Would this have the same effect as what you describe? Thanks.
Jenny
I used 2 bolts because I was concerned the two pieces could twist out of alignment (pivot around the one bolt) if I only used one. From your experience, this doesn't happen?
Also, I did drill and put the bolts in and out of the last before I cut the last in two. Would this have the same effect as what you describe? Thanks.
Jenny