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Ok,I broke a shedua side on the pipe. Made a bender,bought a blanket,broke the second side, I spritzed and wetted the kraft paper,but let it dry,maybe too long. Third,soaked the kraft paper,spritzed the wood with no dry spots,heated and bent @ 300 deg. Cracked in the waist and upper bout. Fourth time, soaked the kraft,spritzed wood like I was washing windows,bent @ 340 deg,broke. I thinned to .075 and .070 at the waist and upper bout.Has anyone bent ovangkol with good results? I have one more set,but I wanted to get some opinions first. Clinton

Clinton,
I know Matt Gage has used it before without a hitch.
He might have some additional info to share.

Ah Man, so sorry to hear that Clinton, i hope you'll get all the help you need.

Serge

Sorry to hear that... yupp like Steve says, I bent it without a problem. I dont use alot of moisture in my bending,i do a quick wipe with a damp rag and thats it.

perhaps too much moisture is not good in this case?

good luck with your next attempt.. been there.

Matt

I do the same thing as Matt, I also use aluminum foil not kraft paper (although, that probably don't matter). Just a quick wipe on each side with a wet rag, fold in foil and bend. I don't use a thermometer, I simply turn my blanket to about 90% and wait until I hear the water sizzle (about 30 seconds or so) at that point it takes me about 1 minute to complete the bend, I also back down the heat to about 60%. I do the waist first, all but about 1/4", then the lower bout, upper bout, finally I finish the waist bend, that pulls it all tight to the form. Shut the heat off, and let it cool.

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Lance@LuthiersForum.com

Clinton,

Are you letting the wetted side get hot in/under the blanket for 10 or so minutes before bending?

Greg

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Gwaltney Guitars

I use foil and paper to help trap the moisture in, in case it might help.

Clinton,

I remember breaking a few upper bouts in Indian Rosewood. You may be experiencing cool spots in your bending. Where are you measuring your temps? You should spot measure I put my digital WalMart Probe on the wood/blanket under the wood or placed on the wood from above covered by a glove to get a good reading.

When I discovered my problem it was simple. An overhead ceiling fan was blowing cool air down right at the upper bout, CRAAAAAAAAAAAAAAAACK! So it can be very simple.

Bending with a blanket takes about ten minutes start to finish, bulbs take longer. Do you have a digital probe or a spot thermometer?

Another problem is overcooking wood, scorching at the waist. You haven't mentioned if your wood is scorching. Is your wood scorching? If it's not, you really may not be getting it as hot as you think.

I've had that problem especially with lighter color woods like sapele and maple. That is why in addition to a bending form, silicone blanket, and two internal bulbs, I now bend the waist complete by hand over a hot pipe.

Once the waist bend is finished it takes a few minutes to spritz, cover with tinfoil, then install in the bending form. What happens, is that the waist bend is cooling those few minutes, eliminating scorching of the waist.

Watching the Friday Shop Tour Videos from Taylor you'll see they now do two benders, one for the waist, one for both bouts. No water, just paper. Incredible, but the comment that makes complete sense, "We only make outside bends now." In other works they are only bending over a form in this case. It's an eye opener and really clicks in the old brain matter what's needed to make quality bends.

I can't wait until the next time I get to bend again, it's so much fun now. Keep at it, and listen to these guys, you'll get it. It could be the wood but I doubt it, if it's quartered with little runout. Wood with much runout could do what you are suggesting. I have had some sapele from a nameless supplier and there was no bending it, the runout was about 45 degrees, way to much. Good luck.

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http://www.dickeyguitars.com

A light spritz of Super Soft 2 (grain relaxer) has saved my bacon on several occasions. I swear by it now.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Clinton, I notice that all your bends were made at over 300 degrees. Have you tried starting the bend a little earlier? I mean somewhere around 240 degrees or so? I use craft paper which has been soaked and start my bends at 240 and haven't broken a side since using this technique.

I start with the waist, then the lower bout and finally the upper bout. By the time everything is bent I am approaching 300 degrees. I'm thinking that you might be cooking the wood till it is too dry before trying to make your bends.

Keep trying, you'll find a method that works for you.

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Dave Rector
Rector Guitars

It sounds like I use a little different system than most so my 5-10 minutes of pre-heating may not be appropriate for your use.

Greg

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Gwaltney Guitars

Pics would be so helpful.

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http://www.dickeyguitars.com

Yes, I've scorched a couple, I think I warmed it too long before I started to bend. The next time I tried to bend @ 270 deg, however it didn't want to "release" like some of the other woods I've bent,granted they probably the easy woods:wlanut,hickory,sapele and mrytle. I'm soaking the kraft pretty good, maybe I should try the foil where the foil shouldn't dry as quick and I can use less moisture. Maybe I'm taking too long to make my bends and it's completely dry before I'm finished. I also tried turning the bulbs down after I'm about 75% bent to prevent scorching. Another thing, I'm only turning on the blanket about 50% and waiting a good 7 minutes before I'm reaching 250 deg. My blanket is on top of the sandwhich? Blanket/slat/wood wrapped in kraft/slat/bending form, top to bottom. I really appreciate all the ideas. Keep them coming! Clinton

Putting the blanket underneath might help...
Seven minutes to wait for wood to heat up is too long. You want to get up to temp quickly, and then bend carefully.

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Again, this is often a tough wood to bend. After I broke an ovangkol side, I added 10% glycerin to the distilled spritz water I usually use and it bent.

Now does adding glycerin (or super soft) _really_ help? I dunno, but if jumping up and down on one leg seems to help bend the tough stuff, then I guess I'm willing to hop.

[QUOTE=Bob Steidl]if jumping up and down on one leg seems to help bend the tough stuff, then I guess I'm willing to hop.
[/QUOTE]

I'd pay a few bucks to see that Bob.   

I have some Ovangkol that came from Ed. It smelled amazingly like a urine spot on the carpet. I remember the photos showing something like large flames in the wood. I'm wondering if it's just a PITA to bend. It's still on the shelf. Someday maybe I'll find out what's ailing Clinton.

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You shouldn't pee on the carpet Bruce, unless of course it helps you bend sides w/o breaking them...

It does seem to be a systematic pain to bend for sure, though some pieces will go. Some woods are just that way, I guess...

Makes nice guitars though.

What exactly is glycerin? An oil? I'll look for SuperSoft. I will also try putting the blanket in the sandwhich and turn it up to 90% and see if that helps. At this point I'll jump on one foot as I pee on the carpet if it helps! Should I post pictures? Clinton

This might not be helpful directly, but the steam bending classification for Ovangkol according to my "World Woods in Color" book:

Mechanical properties: Has medium strength properties in each category but only a POOR steam bending classification, as shallow bends only are possible.

Many "new" woods can be researched to see where they rate in perspective to "traditional" woods for working properties. Ovangkol is a tough one to master apparently.

That's interesting, I'm going to have to see if I can't get my hands on that book. You wouldn't happen to know where I can pick one ? Clinton

I think Don made a good point here, I use the Light Bulb system, but if a blanket is on the top of the sandwich with the wood underneath, heat rises, maybe as Don recommends, place the blanket beneath the wood in the sandwich. My thinking would be the heat would still rise, but through the wood rather than heat the top steel bending slat.

If I am confused on your sandwich making disregard

Mike

[QUOTE=crich] That's interesting, I'm going to have to see if I can't get my hands on that book. You wouldn't happen to know where I can pick one ? Clinton[/QUOTE]

Clinton, I'm sure you can get it on line or any good book store will order it if not in stock. "World Woods in Color", William A. Lincoln, ISBN 0-941936-20-1 reprinted 1994, 1996.

While it's a great reference book, it's only one source of research material. I have a full library of collecting for 30 years. US Forrest Service is a main source of wood technical information and many of their studies and publications are available on line or in their Wood Handbook.

I wouldn't expect many eBay wood sellers to know much about their products, but good instrument wood suppliers should be able to convey much of this important information to the consumer if asked specifically about a wood offering. It's part of the business to know and a consumer should rely on their pusher...er....seller...er.dealer...er..hummmm...broker..yea h..wood broker...

Well, yes Larry you make an excellent point. I personally have not bent Ovangkol, so as a pusher....er, dealer....er...broker, it would have been great to be able to pass on that info, but alas I was not able to do so. Sometimes you just run across nice wood that you know will sell, and buy it.
That said, it's probably a good idea also for customers to ask the questions of others before bending, rather than after the cracking noise.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Hi Don, didn't mean to step on toes and I had no idea where Clinton's wood came from. My post is pretty generic and certainly not intended to "blame" just point out some stuff.

I agree that users/consumers have a shared responsibility in understanding the ramifications of purchase undertakings, but most/many hobby builders don't know what questions to ask or even that information about wood properties is available or aren't in to research or don't care about understanding the wood and it is part of a suppliers duty to assist or warn a prospective user of difficulties that "may" be encountered. Wood working skills learned on alder won't necessarily work on wenge so to speak.

Tips shared by the experienced guys who have worked certain woods is invaluable.

Wood purchased for it's "pretty" factor first and not it's grain orientation or working properties first often result in thread titles, "Help...my wood cracked" on many forums.

As always, I could be wrong but it works for me.