The Crispin Colloquy

Contrastingly, what I am looking for in a ballroom dance shoe is something closer to being barefoot, only with a defined heel edge, a wear surface made of a dead cow's skin rather than my own, and the option of incorporating a thin rubber pad under the ball of foot in some but not all pairs. Dancing in a shoe with welted construction, or a vegetabe sole or suede covered molded rubber one is fine for casual purposes, but doesn't allow the foot to flex or roll inwards sufficiently to softly receive weight in expansive competition movements. Almost the opposite of orthapedic shoes which try to releave pressure points, the goal here is to allow the dancer's foot muscles and knee trajectory to focus the weight in a specific area. I have shoes that do this - its just that the ones that best match my feet are very poorly made.

Conceptually speaking, if there was some sort of nanotech brushable liquid leather, I think I could get what I want by molding some modelling clay to fill in my toes, putting on a protective sock, brushing the shoe over that, and then attaching the heel and suede forsole. Since that doesn't exist, I'm envisioning the last as a surrogate for precisely sizing (more so than shaping) an assembly of leather pieces. For a stiffer shoe, shape and buildup relative to the foot would presumably be more critical.

To answer your question DW, for me, I started out making lasts at an orthopaedic shop, first with plaster then polyurethane and it takes a lot of work to achieve the sophisticated forms that I want my shoes to reflect. Better to leave lastmaking to lastmakers.

If I was working on your project Chris, I would recommend starting with a commercial last and then building a lightweight shoe on to it. Try a soling leather shank and a chrome leather sole, that's what I've used in the past for dancers and it's been successful.

Jon,

To answer your question DW, for me, I started out making lasts at an orthopaedic shop, first with plaster then polyurethane and it takes a lot of work to achieve the sophisticated forms that I want my shoes to reflect. Better to leave lastmaking to lastmakers.

My point exactly. I think all of us who started pouring plaster and then moved on to real lasts feel the same way.

BTW, I used to cast the foot using plaster impregnated surgical bandages, make a cast from that, create a toe shape, modify to heel height and style and then re-cast in polyurethane. Probably similar to what you did.

I have nothing but the utmost respect for those orthopedic guys who can make a good fitting shoe from a plaster cast, and even more respect for the few (from what I've seen) who can make, not only a good fitting shoe but, a stylish shoe from a plaster cast.

To answer my own question...in a round-about way...I guess it comes down to deciding whether you want to model feet or make good looking shoes, that (hopefully) fit near-as-nevermind as well as, and maybe better (factoring in gait and support issues) than a shoe made from a plaster cast.

...at least it does for me.


Tight Stitches
DWFII--HCC Member

I have a question about vintage lasts. When did they start making the cone lasts with a metal heel plate for nailing. Most of my vintage lasts come from Rios of Mercedes and I believe these to be 1880's to early 1900's (ie. before 1910). If anyone can shed some light on this, I would appreciate it. Rios was founded in 1853.

Cheers,

JesseLee

I remembered last night that I had a 500 gram bag of shapelock plastic pellets - a polycaprolactone modeling plastic which melts in hot water and can be molded with fingers when not too hot. I think Rick had looked into using this previously for a shank... but at the moment what I need is a last that matches at least the girth of my foot.

So I made up a sort of footbed of a desired heel, a well worn drugstore insole, and foamcore for toe spring. sat a softened sheet of plastic on it, and wrapped it up around my foot. When this cooled I trimmed it, and molded another piece to my heel. Then I did another for the top of my foot. The plastic doesn't stick to itself too well when it's not really hot, so the mold pieces are separable and requires some tape to hold together.

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Compared to the plaster bandage cast I made on Friday, this was faster, cools in a few minutes, and was way less messy - the material was about 2x as expensive, but will be re-usable if I chop it up.

Question now is if by pouring in stages and perhaps immersing the whole thing in a plastic bag in a cold (or ice?) water bath, can I cast a plaster positive to re-sculpt without generating so much heat that the plastic softens?

(Message edited by ccs on January 09, 2011)

As this formulation of the polycaprolactone is sculptable but not pourable, I can't think of a way to directly make a last out of this (and it would be expensive). But a test I did shows it takes nails quite well - and a little heat should rejuvenate the nailing surface.

If I had a plaster negative mold, it might be interesting to shape the warm plastic to the footbed, heel, cone, etc areas and then fill the bulk volume with expanding foam.

(Message edited by ccs on January 09, 2011)

No problem with plaster curing heat softening the plastic. Demolding reveals I'm going to have to do some carving particularly where mold edges met, but I have a shape to experiment with, which was the goal.

What's the preferred way of duplicating a last into something like liquid last? With a flexible rubber negative mold, or a two piece one in more plaster? If two piece, is it a left and right half, or a top and bottom?

(Message edited by ccs on January 09, 2011)

Chris, You can get Pour a Kast. It is a plastic you pour into a negitive. You can order it from Seattle pottry ( you can google them) It is pretty stiff like the turned last. You will need to shape your plaster last first, then make a new mould of the plaster last to then pour : por a kast into the new mould. Alternatively, I hear that smoothon.com has other plastic materials that you can use.

The only way that I know of you can last a shoe over a plaster last is by using the string the lasted method.

Have you taken a look at George Kellof's book. Many people have had great sucess with his system. I belive I saw some of Ricks posted here trials and errors on They system George presents when rick first started out a few years ago.

A flexible rubber mould is only useful if you plan on making many duplicates of the same last.Rubber is expensive to buy. Here are some pics of a type of mould making in plaster. http://lastmakingschool.com/Brochure/page%207.htm

It is a called a multi piece mould.

You could get away with only a two piece mould. two halves of the last the long way. We use, a 5 piece mould because of the type of process we do.

the mould shown is made from the plaster foot model. the plaster foot model is made from a plaster bandage mould that was made by wrapping the bandages it around the foot.

Once we have this plaster mould we use lastmakers clay to do our shaping with. However, many people simply use plaster to do thier shaping with. It is relitively inexpensive and it can be additive and subtractive.

Once you have a shape you want, you make another mould of that, don't forget to have a pour hole in your mould and pour Por-a-kast into it. You will need to band the two halves together or you will have leakage. also, Seal the cracks on the outside of the mould with clay this will stop any leakage.

Anyway, i hope this helps.

-Marlietta Schock
Lastmakingschool.com

The only way that I know of you can last a shoe over a plaster last is by using the string the lasted method.

I think I just re-invented that, making an upholstery fabric fitter by sewing the lasting allowances across the insole.

I'd given some thought to making some kind of jig with pieces of tiny chain with hooks on the end, and then the chain hooked over a wooden plate tack clued to the insole with nails sticking out of the perimeter that the chains could be hooked on at various lengths - might be interesting with an upper that needs to be stretched repeatedly (before I read about pliers and tacks, I assumed it was done with something like this).

I think I'm going to try the 3 or more piece negative mold in plaster or water putty once I clean up the foot casting a bit more. And then I'll probably go for smooth on urethane plastic or maybe this pour a kast; I decided the cost savings of bondo/liquid last isn't worth the extended curing/outgassing during of ventilation at this time of year. Just have to decide 300Q or one of the slower versions or pour a kast (I'd also like to make some heel pieces from it, and know the smooth on product has been used for that)

Chris,

Use 300 instead of 300Q. I used the 300Q when pouring into a casting sock only because I want the plastic to cure faster than the heat would distort the casting sock.

If that is not an issue for you, you will be happier with a more relaxed time frame for mixing and pouring the plastic.

I was already narrowing in on 300, so that's good to hear.

Anyone every tried casting one with a foam (either polysterene or polyurethane floral) block inside the thickest area, to reduce the amount of resin used? Or plywood or something if it were baked bone dry.

Concern though is it may make it harder to put a bolt in for a split - had a lot of fun getting my fabric fitter off the plaster temporary last without that!

(Message edited by ccs on January 11, 2011)

The densest foam I could find in the US was still not dense enough for hammering and nailing. Although, I know they have such a product in Europe that is used to make lasts.

I had been meaning a solid block inserted before the plastic was cast around it leaving a heavy wall thickness of cast plastic at least on all work surfaces - though if you really need something that can be used as an anvil, that may not work.

Chris, to reduce the amount of plastic you need, I have used sawdust in the mix. Think of the plastic as glue for the sawdust instead of a total plastic last. It looks real nasty if you use large chunks so use more of sawdust flour. You can get this free from loews or home depot behind the panel saw. Simply ask them if you would be allowed to clean out some of thier saw dust behind the panel saw. A good ratio is 50 percent mixed plastic to 50% sawdust by volume.

Por-a-cast I like the best, it really holds lasting tacks well.

As far as string lasting, there is a book, I forget it's name produced by clarks shoes. In the book it shows how to string last boots and shoes. Also, a book produced by mary loomis, explains string lasting. However, the clark book explains it better. What is shown, is very effecient and you don't have to reinvent the wheel, unless of course that is part of your creative process. I know sometimes in order for me to understand a process, I go through the steps of reinvention. Others, simply follow what has been done before. I guess it is simply a matter of preferance.

Oh yeh,

If you are going to pour anything into plaster, You MUST USE A MOULD RELEASE!!!! OR YOU WILL BE.....REALLY ANGRY IT ALL STUCK TOGETHER LIKE A BIG LUMP. I guarentee you will be cussing up a storm!!!!! Seattle pottery sells mold soap. follow thier directions. Also, I explained ealier to Andre how to use mold soap on plaster. Look at post from fall 20010.

-Marlietta
Lastmakingschool.com

(Message edited by Last_maker on January 12, 2011)

Even reshaped to be more last-like than foot-like my plaster positive casting still has enough complexities that the base piece of my plaster negative mold failed.

I could go get some alginate or molding rubber (was lucky to find a local supplier), but my large order of polycaprolactone beads which soften in hot water (instamorph, friendly plastic, shapelock, etc) just arrived. This seems like it may be a very nice material for "not sure yet" lasts-in-progress since it's reworkable (and re-usable), and it takes nails nicely.

So I'm now casting my foot in a 3 piece plaster mold - have the base and front part done, just need to do the heel. I kept the inital pour thin so I didn't risk burning myself (and could have gotten out of it in seconds if I needed to). Plan is to try hand filling this with the plastic - I have enough now to make it solid if I need to, but my hope is to have a plastic work surface (and solid toes) but then fill the bulk mass of the foot with something cheaper like polyurethane foam or plaster - and that way I'll have enough to do both feet.

(Message edited by ccs on January 13, 2011)

Chris,

I think your process sounds more complicated than it needs to be. When you cast feet, it is best to cast them the same way the podiatrist do in order to capture the arch in the proper position.

Also, use Plaster Bandages! They are flexible and the conform to the foot better. Let the plaster bandage mould dry for a week. Pour mold soap in the hollow and make sure it swishes around well. Let dry and repeat.

You can also make multi part moulds out of plaster bandages utilizing the bi-valve method. [ how to do this is to long to explain here].

It is a lot of effort to make a last, and especially making a last from a cast. Making short cuts in this step of making sure the cast is balanced thus the mould, is cheating yourself out of an excellent well balanced last. DON'T TRY TO CAST YOURSELF!!! Get a qualified individual who knows how to cast feet, cast your foot pair. manufactured lasts are already balanced. Creating an unbalnaced last could come back to bit you in the butt litterally or the hip for hip pain, knee joint pain, back and neck pain.

As DW said we all start out by being interested in this foot casting thing, but I have got to say that I had to learn how to alter lasts before, I learned how to make them. Think of it this way, Your foot is inside the shoe right? Thus, your foot is theoretically inside the last. however, After your foot is inside the last, you have to add leathers( fittings) to build out the last for a good fit. As long as your last fits you heel to ball, it is a good starting point. think of a last blank as a filling volume and you simply have to sculpt around it to get the shape and fit you want. It is already manufactured to have the parts of the last in thier right place necessary, and you don't have to go into last design theory to make sure your last turns out, you just add and subtract till the last fits you.

Well, that is my two cents for what its worth.

-Marlietta

With regard to balance, in a shoe with any stiffness and designed for a normal gait of solo walking, I'd probably agree. But the targeted shoes take all of their form from the foot they enclose, and are intended to allow the user to move their weight through the foot in non-usual patterns more fitting to ballroom movements. There are only a few areas where the shoe is not in full contact with the foot - and those are either fit errors, or concavities which a covering would not naturally follow. A primary reason I finally started with this project was the realization that a lot of the poor ballroom footwork one sees is in no small part due to certain styles of shoes that are stiff enough with respect to twist that they discourage development of the necessary habits of weight placement.

A commercially purchased last won't be any closer to meeting this need that what I've already produced, which captures the shape of the specific foot that I want the shoe to adapt to with less "battle" (and eventual tearing) than commercially made shoes do. If I had a commercially produced last on hand, I'd probably duplicate it and rework the duplicate rather than ruin the original. What interests me about the polycaprolactone is the ability to add and subtract while remaining with the original material, and recycle the experiments.

(Message edited by ccs on January 14, 2011)

Turns out two pounds of polycaprolactone is almost enough for one last - I'll just need a little more of the second bag for the ankle area to provide something to put a screw into. So while about 2.5x the cost of polyurethane plastic, a mistake only means the cost of hacking it into re-meltable sized pieces. Tomorrow's challenge will be to figure out how to saw the ankle - it's gumming up enough to trap a woodcutting hand miter saw. Will have to try a hack saw and hope less friction given less blade area, or a tree cutting saw with the teeth canted out, or maybe rig up something with a hot blade or hot wire. Or maybe just putting it in the freezer first will work (it's still got some residual heat an hour after I formed it)

(Message edited by ccs on January 15, 2011)

Finally sawed through the polycaprolactone with a bow saw and did a packing tape fitter.


It was a little short, so I molded some more plastic on the toe. Melted the extra in hot water water, preheated the toe area with a heat gun to make the existing part tacky so it would fully weld. Here the addition hasn't cooled yet and so is still translucent and somewhat moldable. Think I will need to carve off a little to round it more.


And moved on to a fabric fitter. The aluminum push pins seem to work well - can be started with finger pressure and then tapped with a hammer, though there's a limit to how close together they can go so I may need to use tacks instead in some areas.

(Message edited by ccs on January 19, 2011)

Here's a question.

What does the A signify in a last model A352?
I have a JV last A352 10AA.
It seems to be much shorter and narrower than last model 0352 10AA.

TIA,
Paul

Paul,

I don't know. I had a last model designated 352 (no zero, no "a" ) but that was an old Kretler Brothers designation. Neither Bill nor JV used it as far as I know.

So...I'm not sure what either number actually means or refers to.

Tight Stitches
DWFII--HCC Member

Paul,

I think 10AA is the last size and AA is the width, A352 could be the serial number of the run of that specific last and it is for factory reference/use, I have some factory lasts and they all serial numbers on the sides and the sizes are usually marked in the front(on the cone or lower).

Nasser

I am trying to shape the toes on my lasts, so far I have been just kind of eyeballing them and trying to make them look good.

How are you supposed to do it? I looked in Golding one at the last insole construction but it didnt seem to say much about the toes.

Obviously you have to follow the foot, but then do you try to make the very end of the toes straight like the center line of the last or curve in to follow the foot?

How do you make the toes symetrical if the outside is bigger than the inside and has a different curve?

I dont know if I'm being clear, but hopefully it makes sense?

Courtney

Courtney,

Yes, you have to follow the foot. But you also have to respect the lines of the last.

The last is "functional sculpture"--except for the featherlines, it is composed of curves...all curves. And all "fair curves."

Take a last and hold it up to the light. Squint at it such that all you see is a silhouette. Slowly rotate the last...in any direction....and watch that silhouette change. Notice the way the "lines" of the last flow into each other.

Just because you add a build-up, that principle--of flowing lines--is not negated.

Any addition to the toe of the last, any subtraction from the toe of the last, should blend...in all dimensions...into the rest of the last. If after building-up the toe, you do the "profile (squint) test" and you see a "hump"--a deviation from the lines of the last--in any of the infinite number of rotated planes you are observing in the light, the buildup is awkward, to say the least.

As for where you place the build-ups to alter the toe of the last, my old teacher always said "one-third medial, two-thirds lateral." That's probably a good rule of thumb. But as you have already come to understand, accommodating the footprint is as, or more, important than any arbitrary rule.

Finally, go down to the hardware store and purchase a "contour gauge." Get a good one...not plastic. This will allow you to take/make a template from the shape and size of one toe and transfer it to the other.

Hope this helps...


Tight Stitches
DWFII--HCC Member

(Message edited by dw on February 24, 2011)

(Message edited by admin on February 24, 2011)

Thanks, D.W.,
I guess what I'm trying to figure out is,

If I find the center line by drawing a line from the joints of my foot to the breast of my heel, divide the heel width and then run the line through the the center of my second toe,

That should be the center of the toe shape I build on the last right?

And then if I was to cut the end of the toe off and fold it in half should it be symetrical or not?

Also if my feet are two different widths in the toes should I try and make the end of the toe shape two different widths or the same?

If they are the same wouldnt the sharper angle from the outside joint to the toe on the larger look obvious?

I'm still not sure I know what I'm trying to ask but I think this might be it.

Heres a picture from Golding that shows toe shapes that the center is not in line with the second toe, So how do you find it?


Also, how much length past the longest toe would be considered way too much?

(Message edited by courtney on February 24, 2011)