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My plan was to bend my sides last weekend and I procrastinated all weekend, and all day yesterday. I guess I'm apprehensive since I have only bent unfigured rosewood in the past and it bends so easily. This set is curly purpleheart, and it seems to be kind of splintery. I've thicknessed the sides to around 2-2.2 mm for a small Torres style classical. I'll be bending in a bending machine built from the LMI plans, heated with light bulbs, which has worked fine for me in the past. My question is, when you are bending a figured and splintery type of wood, is it better to get it wetter than usual? Should I wrap it in kraft paper? I don't think I would be able to replace these sides, and the back is so beautiful I hate to waste it. I resawed it all years ago from a board I found, on a bandsaw that is way too small. I actually almost burned up the motor doing it and was able to get just enough for 1 guitar. Any advice would be appreciated. Wendy

Have you heard of supersoft? It is supposed to help a lot for bending.

Speaking of supersoft has anyone found a source for it in Canada, I hate to order from the US as they shipping is as much as the product.

As to bending figured wood the light bulb benders are not as good as using a heat Blanket. I figured when I built my bender last year the cost of a broken side would cover the cost of a blanket.

Fred

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Fred Tellier
http://www.fetellierguitars.com
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I have heard of supersoft, but I read somewhere that it can bleach some color out of the wood. And I wish I had a blanket, but I am in the process of building my last 3 guitars. I'm building 3 because I already had the materials for these 3 and I don't think I will be building again, so I hate to spend the money. I guess if I knew 100% that a blanket would save the sides I would consider it. Wendy

Why are you giving up building?

First of all, thin it more. Especially if you want to be true to the Torres style, 2-2.2 is way thick. Make them 1.8 (which is still thick) but at least they will bend MUCH easier than at 2-2.2.

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Build log

OK, thanks Alexandru, I will thin them some more. I don't know where I came up with the 2mm figure. I just looked at my plans and they do not specify a thickness for the sides. So do curly figured woods in general need to be wetted more before bending? The 2nd set I need to bend is curly birdseye maple. I'm not looking forward to that either. At least the 3rd set is good old easy East Indian Rosewood.

I'm giving up building for a couple of reasons, but mostly due to a health issue that is affecting my vision. Its becoming a strain to do fine detail even with magnifiers on top of magnifiers. Also, because I miss playing the guitar. It's hard to work fulltime, and try and build on the weekends, and still be able to find time to play. I'm sure any of you who work find the same thing. My active Australian Shepherd is starting to groan when I go into the shop for another of what she considers to be a boring weekend. It's also costing me a fortune to keep my shop temperature and humidity controlled here in AZ. I am starting to sell some equipment, but am covering myself if I decide I have to build another guitar. Like selling my jointer/planer, but taking some of the money and getting a nice hand plane. I've discovered that I like working a lot with hand tools.

2mm is quite a common figure for sides, if not the most used. But for a real Torres box you can go way thinner.

You might actually need to avoid using much water, it is going to increase the risk of warping. Try to do a search as I believe there have been older discussions on bending figured maples. One thing is not to crank up the heat too much, I think I read it scorches easily and deeply.

Myself I hardly use water at all on any wood. I only have a damp rag nearby and if i feel the heat is too high for that piece I am wiping it now and then trying to avoid scorching.

Fact is that when I was using thicker wood and more water (as in wiping very often with a soaked rag) I was getting more cupping and doing the tight classical waist bend was a PITA. Now I do them thinner and dry and it has turned from an unpleasant chore into fun.

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Build log

Re " I read somewhere that [Supersoft] can bleach some color out of the wood:" I would be interested if you can remember where you read this and what the evidence was.

I have some Supersoft and some curly purpleheart, so I did a little test. A day after applying the Supersoft, there was no apparent bleaching. I sanded the treated area and the untreated area next to it, which exposed the lighter wood underneath, but the treated area was no lighter. To simulate finish, I put some naphtha over the treated and untreated areas. There was no difference in color. This doesn't prove that heating and bending plus Supersoft might cause color change; before I bend I might do a test piece. But I'm going to bend a bunch of easy stuff first before I use this set.

Re where you get curly purpleheart--I got this set on eBay. It cost about $65, I think.

Tim, I can't remember exactly where I read it, but I'm pretty sure it was on this forum somewhere. It sounds like you're testing it pretty thoroughly. I was thinking of doing the same thing. I'd love to know who the seller on Ebay is. If I knew I could get some more, I would just go ahead and bend it. I am going to thin it a bit more though, and I may throw in the towel and buy a blanket. I found this board leaning up against the wall in a wood store in Phoenix, about 6 years ago. It was nicely quartersawn. I resawed it and stickered it on a shelf in my shop and it's been there since. If you get around to bending it, I'd like to know what you learn about the best temperature and whether it fades from the supersoft. Wendy

I experimented on a scrap of my curly purpleheart last weekend and I'm very frustrated. I bought supersoft 2. I sprayed it on the wood, wrapped it in kraft paper and let it dry for 3 days weighted under a flat board. After 3 days the wood seemed to be completely dry. I removed the kraft paper and replaced it with fresh paper. I sprayed the paper wrapped wood with distilled water. I had ordered a new heating blanket from Blues Creek and I proceeded to bend the sample in my bender as per Hesh's instructions. My package top to bottom was steel slat, blanket, steel slat, wood wrapped in kraft paper, steel slat. The entire time to bend should have been no longer than 5 or 6 minutes. I was using the same controller as Hesh, which I set on variable with the heat control all the way up. I used a thermometer, and intended to start the waist bend when the temp reached somewhere around 240F. Very quickly I saw what looked like light smoke, even before the temp had gone up much, and I assumed that there was some initial residue on the new blanket that was burning off. I guess it may have been steam, and it stopped after a minute or so. It took a full 6 minutes for the temp to get to 240. The waist bent ok. I let everything cool down and then I was going to recook for a few minutes. When I plugged the blanket back in to recook, there was the same smoke again very quickly. At that point I decided not to bother recooking, since it was only a sample scrap I was bending. When I removed the wood from the bender, there was a lot of dark staining on the wood from the supersoft. It does sand off, but it is a pain and imagine that it would be a lot of sanding for two sides inside and out.

So here's a few questions; 1) I have only bent EI Rosewood before, which is an easier wood, and I used 3) 200 watt bulbs in the bender. The steel slats were always preheated in the bender before wetting and inserting the wood. So the wood was ready to start bending just a few minutes after inserting. With the method I tried this time, it felt like by the time the whole package was preheated, the moisture would already be gone from wood.
2)The entire package was much thicker this time, since it used to be only 2 slats with the wood between. Do you have to compensate in some way with the bending forms or waist caul? I felt like it was very difficult to bend that thick package all the way into the tight Torres waist. Can I eliminate the top slat and put the blanket between the 2 slats directly on the wood? And if yes, will the blanket get stained from the wood if the wood is not wrapped in paper?
3) Does anyone here preheat everything before inserting the wood?

I'm having 2nd thoughts about using the supersoft, due to the staining. It did not seem to make it easier to bend, although I have never bent this wood without, so I can't say for sure.
Wendy

Hi, Wendy,

I don't have the experience myself to help you with your bending, but you might look here:

http://www.luthiercom.org/phpBB3/viewto ... &sk=t&sd=a

and here:

http://www.luthiercom.org/phpBB3/viewto ... 136#p27136

for a solution to some difficult bending.

Joe

I have used SuperSoft II following instructions from Todd Scott posted on MIMF. I haven't used it on purplheart, just on curly maple. Waiting 3 days probably won't work--you have to act after it dries but within about 24 hours. I found that after 2 days, the softening affect was gone and the binding strips I was bending--which had a lot of runout--snapped just as they had without SuperSoft.

Re the "dark staining from the SuperSoft"--I haven't heard of that, just as I haven't heard of the bleaching you talked of in an early post. I wonder if the wood wasn't scorched.

The new bending setup may be a problem too. I'd suggest you get the blanket and everything else to work with walnut or rosewood scraps first, then move on the the purpleheart.

Please let us know how it works or doesn't work.

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Tim Allen
"Never hurry, never rest."

Tim, it was here on the forum that I found the instructions for waiting 3 days before bending. I just tried to insert a link to the topic here, but it is not working. The forum archive topic is Super-soft 2. Also, it was definitly not scorching, but a dark purple staining. When I unwrapped the wood after 3 days, the kraft paper had some staining on it, I read that you will get staining if you don't let the super soft completely dry before bending, hence the 3 day wait. The wood felt completely dry, but maybe I had used too much supersoft and it got rewet on the surface when I sprayed it with water to bend. Wendy

Joe, thanks for the links to those discussions, I may boil a small piece of purpleheart tonight just out of curiousity. Wendy

You're welcome, I hope it helps!

Well today I decided to just go ahead and bend one of the purpleheart sides without supersoft. It seems to have bent fairly easily, I did not hear or feel anything cracking, so I'm hoping there will not be a surprise when I take it out of the bender. I do have 2 problems. One is kind of funny, I guess. In my rush to get everything lined up and in place while it was heating, I forgot to take the protective sheath off the probe of the thermometer. Of course it melted, but it did not stick to anything. I was able to pull the melted cover off and I am hoping the thermometer is still usable. The other is that I think I may not have gotten the waist cranked quite all the way down. So much for my fading eyesight. At the time it looked like it was all the way down, but now, looking through the slot in the waist of the bender, there seems to be a slight gap. Is there anyway to re-wet the waist, reheat and crank it all the way down? Or is it a done deal once you bend it and set the bend? Wendy

Please! Post a pic of Curly Purple Heart. I really wanna see what it looks like.

Thanks!!

Mike

Edit: Also, does Curly Yellow Heart exist?

Sorry Mike, but my digital camera broke a couple of weeks ago. Maybe someone else can post a picture? Wendy

OK, Here's a new twist. I bent the purpleheart side without supersoft and it bent fine, but it came out with the same dark staining just from water as what I thought was from the supersoft. It is definitely not scorching, it is in the pattern of liquid running on the wood and it is dark purple. It does sand off. It's weird. I've never seen anything like that before. If I hadn't gotten that lumber and resawed it myself, I would swear it was dyed, but I know it's not. Wendy

Dang! We need to get you a new camera!!