One "Last" Question

[jenny_fleishman]

Erick,

I take the Brown Line to the Merchandise Mart stop for work, so maybe I'll stop at Pearl on my way home Monday. Thanks for the info!

Jenny

[relferink]

Eric,
I'd try roughing the last very well, than prime and glue with Renia. Let it sit for a day. Take a dense EVA like Soleflex. Rough it on a grinder, than clean with thinner and when dry glue both the EVA and last with Renia. Let dry for about 2 hours. Heat EVA in oven and heat last with heat gun, not to much all you want to do is reactivate the glue on the last and make the EVA playable. Glue and press the piece to the last. Let it sit for 24 hours before you start grinding on it. A good way to press it is take a couple of yards of elastic strap, about 2 inches wide and wrap it as tight as you can around the last, staple it in place and let it sit.

That's how I would do it but there may be better ways, anybody with suggestions feel free to jump in. Leather on the Polyethylene lasts does not finish smoothly, on wood it blends in nicely as long as you glue to grain to the last.

That's my 2 cents

Rob

[tamsin]

Hi everyone,

I went on a beginner shoe making course last weekend, and now I'm considering getting my first pair of lasts.

However I don't really understand the different plate options. I can have a toe plate, a seat plate (heel), half plate or full plate.

According to the last people 'Your choice will depend on how you are going to make the shoes'.

I made a pair of ladies heeled mules, and at the moment I'm only really interested in ladies fashion shoes, however I have no idea which plate is best for this, On the course, my last had a full plate, where as other people had half plates and some none at all.

Any suggestions as to which option I should choose?

Thanks.

Tamsin.

[frank_jones]

Tamsin

First I would like to welcome you to the Colloquy.

Metal bottom plates were originally added to lasts to clench the lasting tacks. In the days before modern adhesives (say before 1960) most flat lasted shoes had the lasting margin fixed to the insole using tacks. These were not the temporary tacks or nails commonly used by hand shoemakers but a permanent attachment of the lasting margin to the insole. The very short tacks hit the metal plate on the last and the sharp point curled over. In the last 40 year or so footwear factories have gone over almost entirely to cement lasting. With no tacks the plates are no longer needed. However some factories still tack the seat area (around the heel) and you still get some new lasts with seat plates. Also, with pointed toes shapes factories have found a small metal toe plate provides support for lasts with very pointed toes.

It sounds as if your course group was working with a mixed bag of old ex-factory lasts.

If you are ordering new lasts purely for hand shoemaking, then you don’t need plated lasts.

Frank Jones
frank.jones@shoemaking.com

[erickgeer]

Frank,

Thank you for the description- I couldn't quite complete a sentence this AM. Good to know I'm not mis-informing my students.

Erick

[erickgeer]

Rob,

I've begun the proccess you described- so far so good, but we'll see if I followed your instructions close enough when I start grinding.

I'm doing this with a whole size run (no widths). The Renia is powerfully strong smelling- I was wearing a respirator while using it and it still smelled strongly- do I need to practice any additional precautions from "all purpose" when using this stuff?

I'm going to buy a glass jar for it - I'm hoping the plastic brushes are compatible.

Thank you for the proccess.

Erick

[relferink]

Eric,

Before you start grinding take a knife and cut off some of the access. when the grinder gets a grip on a piece that is flapping it will still pull it loose. The best way to use the Renia (Colle De Cologne) is with a downdraft table. It's very strong smelling stuff so I imagine it's not good to breath in but it is good glue!
If you use the respirator try to use a carbon filter. I believe that the organic solvents that are most harmful will attach to the carbon and not get in your longs as much. Don't quote me on that but it should be better than a straight particle filter.
I use the plastic jar but I would imagine glass works fine as long as you don't drop them (that's why I use plastic) The glue does have a limited shelf life so close the jars and cans well and don't buy much more than you will use up in a month or 2.

Good luck with the grinding!
Rob

[erickgeer]

Thanks Rob,

I invested in an organic vapors mask back when I was keen on Plastic resins in College (no, the filter isn't that old)

I need a downdrafttable- the ones they sell from the Ortho suppliers are way too expensive. I would like to find plans for the venting system... I can build a table no-problem, but seeling and venting is important- the charcoal filter would be good.

Thanks,

Erick

[das]

Erick,

If it's any help, I saw a really neat down-draft table at Bill Klingbiel's, made out of a huge old BBQ grille, complete with its stand, with a big hood fabricated out of galvanized sheet metal. The big dish for the coals was left intact, but a pipe [like dryer vent, or wood stove flue] was attached to the bottom as the down-draft chimney, that went off through a blower and out the wall. The glued pieces were coated on, and then laid on the rotating grille part to set up. All very clever I thought, and old Webber BBQ grilles are easy to find at yard-sales.

[relferink]

Heat gun update:
Just got home and UPS had delivered the heat gun today, nice in a case with some attachments. 2 air speeds and dial to set temperature. Dial does not feel very sturdy but it should do just fine.

3875.jpg

Jenny, thanks for the heads up I'm happy with this one.

DA, that downdraft grill is a great idea. I just figured out what to do with that old grill in the back yard once the snow has melted. A friend in the shoe repair business came up with the following home build table, it has the sides to keep the vapor in and the back to cut on the draft coming from a window behind it.

3876.jpg

A regular bathroom ceiling fan takes care of the vapors and blows them outside. Works as well as the expensive one from shoe systems plus. I worked on both and don't find a difference. In fact the state came in to my friends shop to do air tests just to see how much of the fumes would still fly around. It passed the test easily, no where near the levels that would be considered unhealthy to work in or that would require additional measures. During the test different cements were used, among them the Du-all and the Colle De Cologne from Renia as well as thinner. All the stuff with the organic solvents that we worry about breathing in.

Rob

[tomo]

Erick, Al,

Al that BBQ idea sounds like a great idea.

You can also invert a range hood and use that, but whatever you use, I think you need to run an earth wire down the inside of of the ducting to dispel any electrical (static) build up as there is a real chance of fumes being ignited. Apparently this is a problem in the wood/ joinery industry as the static build up can combust the sawdust.

Earlier we were discussing the price of glue, well if it ignited, you'd get serious bang for your buck!

More power to y'awl.
T.

[das]

Tom,

Yes, static and volatile fumes would be a concern. I wonder about the sparks in the blower motor igniting the fumes, but Klingbeil's doing production of custom ice skate boots, with Do-All 88 or Barge, and hasn't blown up yet

Aren't there spark-free fans for just such applications? A ground-wire sounds like a good idea too.

[jenny_fleishman]

Rob, are the fumes from the Ortec and Colle De Cologne actually worse than the fumes from Barge?

Has anyone here used Barge with synthetic soling materials, and have you had any problems with it?

Months ago I built a folding gluing booth that sits on my dining room table, has a bathroom vent fan behind it, and can be vented out my dining room window when I am using it. If I ever clean up my dining room enough that I won't totally embarass myself by posting pictures of the mess in the background, I'll post some pictures of it. I haven't used it much because I'M STILL MAKING MY LASTS! I think I'm trapped in a time warp and I'M NEVER GOING TO ESCAPE!

Jenny

[relferink]

Jenny,

The fumes from Colle de Cologne have a sharper smell, the barge is sweeter for lack of a better description. With different type of cement it is often the better it works, the worse it is to work with.
To bond EVA type of soling materials Barge will work fine. Only if you are considering using oil resistant type soling would you consider other things. There are plenty of places that only use barge or similar.

I'm sure it seems a long road to take but the extra attention you pay to the last now is going to pay of majorly later. I know it's hard but trust me I've been there.

Rob

[erickgeer]

Last night when I got home, I got to thinking that the label for the Renia I bought (a quart) looked familiar...

I looked in my fire cabinet this morning and what do I find, but about a half-gallon of the stuff already at my fingertips. When I bought some of my equipment, there were numerous supplies I didn't know what to do with- anything liquid I just set on the shelf of my cabinet and forgot about... that'll (hopefully) teach me...

Rob,

I suppose this has gotten off topic, but the downdraft table your friend built looks great- round-a-bout what I had in mind. I have a big duct waaaaay over head that I need to extend down to a table, but it'll get there eventually (hopefully not too long after I have a table).

I'm not having a pleasant time with the EVA and my lasts- I haven't given up yet, but I'm not sure I'm going to get the pay-off I need. It feels like it may be too squishy for my needs and chunks off at the edges- even when grinding towards the edge. What kind of grinding tip do you use? I have a 1" carbide teardrop on a flex-shaft and am thinking of switching to a flap sander attachment.

I would certainly feel more confident if I was grinding a rigid material that I can form with a hand rasp. I'm thinking of going back to the Bondo-like stuff I used for changing the toe styles a few years ago. I think I stopped using it because of the fumes- but if I'm using Renia or Barge I guess it doesn't make much difference.

I have to go clean up before heading to school now.

Thanks,

Erick

[relferink]

Eric,

When the EVA comes loose, which side has the glue film? If it's the last you probably have to use a primer on the EVA (not very likely) if the film stays on the EVA you may have to rough the last more, I rough it with 40 grit or lower on the sander, it looks very rough but it will give the glue more service to adhear to.
If the EVA is to soft you may be using a cloud like EVA were a soleflex density would be better, from the top of my head, could is 35A shore where soleflex is closer to 60A shore. If the buildup is more than 1/4 inch you may still find it to soft, specifically around the edges, there are some denser rubbers but not easy to work with.
As for sanding it, use sharp sandpaper to reduce the stress on the bond.

It sounds like you working with hand sanding tools like a Dremmel, you would be better of with a stationary grinding wheel. Even a relative small one (1/2 hp or so) It will grind much more even and make a huge difference in the result. If you don't have access to one find a local shoe repair, you may be able to talk them into trying it. If you can use one with long continues sand paper, not the ones with the split you find on a line finisher.
That's all I have to suggest. I'm not sure the bondo would hold unless you can prime the last with some type of solvent to soften it first.

Rob

[erickgeer]

Rob,

I'll have to check on the glue separation. On the sample I prepped today, I primed the last and the EVA.

The piece of EVA I bought says soleflex, but my seller called it cloud. It seems denser when I stick it, but it is kind of squishy at the edges.It's twelve iron, I may just be used to harder substances.

I have a Sutton S-750 compact finisher- I've never mounted the ring sander, and the belt is 6" wide, so it's a bit much for careful grinding. I've used the Naumkeg on the lasts a bit.

I've never had a problem getting Bondo to stick, You have to make sure not to use it where a tack will go in. Bill was recommended the "Bondo Hair" or something similarwith strands in. I bought some once, but I got scared away because the contents looked like the cat had a furball (sorry- a bit gross) and I was skeptical of getting an even blend with the hardener. It could have been a bad can, but I don't know.

Onto a "slightly" older topic- this is for Jenny- Pearl has started carrying some Smooth-On products, if the Eager Plastics is too hard to get to. They don't seem to have the number of choices in resin release agents they used to have, but there are a couple of them...

I'm being called away from the computer, and it's almost bed-time...

Goodnight,

Erick

[jenny_fleishman]

Erick,

If you are going to use Bondo for build-ups but can't tack into it, you might try the Liquid Last recipe I posted previously. It's 1 gallon (or large can) Bondo, plus 1 quart polyester resin, which you can buy at Marine West, 627 W. North Ave., Chicago. You mix the two together and then use the hardener that came with the Bondo.

If you want to use just a small amount, you can mix the Bondo and polyester resin together, take the amount you want to use, and add the proportional amount of the hardener. I use this kitchen scale to weigh ingredients:

http://www.scalesonline.com/Detail.aspx?ID=331

The "tare" feature allows you to set your empty container on the scale and set it to "0" so you are truly weighing only your ingredients. The scale also gives measurements in lbs/ozs or grams. I use grams as it is easier to do the math. When I weigh the Bondo hardener, I just squeeze some out of the tube onto a piece of tinfoil. Someone on this board mentioned weighing ingredients on a scale. If it was you, forgive me for giving you back your own advice!

The LL recipe creates a material that takes tacks well. I can send you a little sample of the material if you like (made in a dixie cup, about an inch high). I don't know if the addition of the polyester resin (which apparently makes the Bondo less brittle) will affect how well it will stick to your last, though.

I did pick up some PVA mold release at Pearl. I'm going to do a test with it before I use it for the real thing, as well as test some floor wax, etc., as mold release.

If you'd like a sample of the LL, e-mail me your address.

Jenny

[erickgeer]

Jenny,

Thank you for the offer of the LL, I'm probably going to stick with the plain product- I shouldn't need to tack into for this job.

I hope the mold release works for you.

As far as weighing ingredients goes, usually (not always) the mainstream products like epoxy putties and Auto body filler are not too finicky for proportions. A tube of putty I used recently allowed for a 20% variation. That said I have no idea what mixing polyester resin with Bondo does to the mixing properties. The higher tech, or specialty mixes sometimes can get very specific.

I was rereading the LL recipe and I had a question:
When you mix bondo and poly resin: You are using the whole can of Bondo plus the (smaller thing of) Poly resin and the whole tube of hardener- no more to account for the added resin?

Thanks,

Erick

[jenny_fleishman]

Erick,

Correct. I called the company that gave me the recipe to double check if I should be using the hardener that comes with the polyester resin as well, and they said no, just the hardener that comes with the Bondo. Seems to work.

Jenny

[jenny_fleishman]

Foot casting question: Pedorthists, and anyone else who makes lasts starting with casts of the feet...what do you use for making the casts of the feet? I used STS ankle casting socks, which work pretty well, but the plastic bag you put over the foot and lower leg before casting is kind of bulky, resulting in some inaccuracy in the mold. Also, the inside surface of mold comes out pretty rough. However, it is a pretty simple technique, and not too messy. Does anyone else use a different method that works well?

Jenny

[jenny_fleishman]

Erick, thanks for the tip about Pearl. In my mold release tests, the EVA mold release I bought there worked the best of the trials. I poured the lasts two days ago and took them out of the molds yesterday. Much of the lasts are nice and smooth, although there are some areas that came out rather rough (not as bad as the other lasts I had made previously, though).

I was a little disappointed that the Liquid Last did have some shrinkage. The lasts are probably about a size 6 or 6.5, and I'd say they lost slightly more that 1/16 inch of length at the end of the toes.

From other postings here I don't think I've heard of an alternative to the Liquid Last recipe I have that takes tacks well. If anyone knows of anything, please post!

Jenny

[jenny_fleishman]

(Message edited by Jenny Fleishman on February 20, 2006)

[jenny_fleishman]

At long last, my lasts are done!

Here's one of them, and a picture of the hardware I ended up using:

3901.jpg

3902.jpg

I would have liked to haved used more than one angle in the cut as Rob posted a photo of, but didn't have the equipment to do it. The hardware consists of a 4 inch Stove Bolt, which has threads from end to end, a screw in insert nut at the bottom, and at the very top I have a nut, a locking washer and a washer.

The insert nut is screwed into the toe part of the last. The hole in the heel part of the last is drilled just wide enough that the stove bolt slips in and out without engaging the threads. After screwing the bolt into the insert nut in the toe part of the last, the heel part of the last can turn freely. I line it up with the toe part and then screw the nut at the top of the stove bolt down until it snugs up with the locking washer and washer.

At this point I found that the two halves of the last (I used cardboard to fill the space lost to the saw cut) did tend to pivot slightly...so I drilled a thin hole and put a thin nail in it to prevent pivoting. Works like a charm. Whether the shoes will fit is another matter!

The lasts are anatomically fairly identical to my feet, except for the toe box and filling in the instep somewhat. I didn't make the usual adjustments (narrowing the ankle area) because I wasn't sure I could get it right, however I plan to attempt to try that on my next pair of lasts.

Jenny

[Tom Mickel]

Hi all,
I have been thinking about building a downdraft table and I've started looking into using a boat bilge blower for the fan. You can get an inline (connects right up to exhaust hose) on both ends and they are IGNITION PROTECTED. There seems to be lots of models and they're not very expensive. The only down side is that they run on 12V so you have to have a transformer.

A friend of mine had a major fire in his house covering 2 stories caused by fumes from lacquering cabinets in the master bedroom. The fire marshall said the ignition point was a FAN that the contractor was using for ventilation!

Just thought this might be useful information to others. Thanks for a great forum.