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I have read most of the recent posts and many archived posts here and on the MIMF about side bending and there is one question that I don't recall being asked and or answer somewhere, so here it is....

In the process of side bending, using a blanket, slats, and bender of some sort, how does one know when the wood itself is ready to bend? I have done 4 guitars, but all were EIR which is very easy to bend me thinks, but know I am getting into other woods and would like to educate myself some more.

So what is it? After the sides are to thickness (0.075-0.085 seems to be about the recommended thickness) light spritz, wrap in something (foil, craft, parchment) slat on bottom, blanket on top of wood wrap, slat, turn on the blanket and wait.........(the $24,000 question) how long? Now I know that we want the whole sandwich to get up to about 250-300*F so using a thermometor is a good idea of course, but can we be certain that the wood is up to temperature? I know that many have said till water dances on the top slat but that would get to temp well before the wood I think as it is right next to the blanket and well, steel conducts much faster than wood,

so...........

Any help here would be helpful, thanks friendsRod True38962.1011689815

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sorry, I haven't used a blanket. I've bent 3 sets of sides. EIR on a hot pipe. then walnut for a mando & a dread using a steam wallpaper stripper. Once it's hot & floppy I clamp it in the mould!!

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I mainly bend on an electric iron. One reason I like the iron is youre always in direct contact with the wood and can constantly guage its "flopiness". I also listen to the wood.....as the fibres start to relax you often hear hear a slight cracking sound. A bit hard to describe but I guess you just get to learn how each wood behaves as it heats up.

Rod, I use two blankets (ala John Mayes) and try to get the temp up to about 240 degrees before starting a bend. I leave the blanket turned up until all the bending is finished, probably reaching somewhere around 270-290 degrees before I'm done.

I also use the wet craft paper on both sides of the sides and haven't had a problem bending anything since John Hall posted this tip.

Once you reach a temp of 212 degrees the water in the craft paper begins to boil and steam the wood and it usually become nice and pliable shortly after that. That's why I wait till about 240 before I start bending.

Also, don't forget to cycle the heat at least one more time after everything is finished to help set the bend and avoid springback.

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Dave Rector
Rector Guitars

Rod - with my one blanket setup, here is how it goes, pretty much regardless of the wood:

1 - thin to 85, then orient sides and mark for bookmatch, take first side, lightly spritz, wrap in foil.

2 - load in fox, orient for waist mark, bottom up is slat/wood/blanket/slat, drop the waist press until the sandwich starts to resist, so it will have a bit of a bend at the waist. Add bout pull downs.

3 - turn on blanket, wait about 2 minutes, then start dropping the wasit screw, 1/2 turn every 20 seconds or so.

4 - when waist is 3/4 the way down, pull down lower bout 1/2 way around - it should be easy by now. Back to waist screw once or twice, then drop the lower bout al the way and tie down.

5 - continue getting waist, start upper bout, going SLOW (1/2 inch every 15 seconds, depending on bout curve slower)and adding downward pressure on caul as you move it.

6 - once upper is done and tied, finish waist and bake 10 minutes - this whole thing takes maybe ten minutes going this slow - if its easier woods liek EIrw, and not so curvy shapes, like a dread or similar, you can go a bit faster.

7 - once cool, reheat/cool one more time for 15 minutes.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

What Tony said is good.

What I say here is probably already known and done by most (excluding items used like foil, papers, 2 heating blankets, light bulbs etc. by others in process.) but who knows maybe a begginer lurking out there who doesn't and looking for ideas. I am speaking on my own and not for my boss/mentor or rep of shop. This though the method he uses and we do in shop. I am an old fat guy, so my time on timer maybe forgotten by me. I do most of this just from doing it often, which is one of the best teacher of all. I go by a mark he showed me on timer, but it is around the time I state. Other issues like reheat and stuff may also be done on occasion. As they say, Stuff happens and sometimes have to adapt to things and do it different, but not very often at his shop.

PREP WORK IS FIRST. Get every thing marked, set and ready for the bender. We use bakers parchment and not foil or other papers. Good enough to work in hot ovens baking stuff, at higher temps than we go with for most part, then should and does work with wood.

Spritz ribs, but not over do the water (particularly with figured woods, which can mess up the grain and cause splits and more scorching). Then to bender ready to go.
    
Once ribs, sltats and those things are setup in bender is when I turn on the one blanket we use for 5 -7 minutes. Needless to say, you don't want to be messing with those things with heat and time going. Burnt fingers and hands are not one of the fun things in building. Right up there with chisle cuts. Getting familier with your particluar setup for timing, heat and all of that stuff maybe a good idea For me that is true using all of my/or shop tools, particularly power ones that can problems, and pain.

I always keep in mind what they are to do, how they are working and though fearing them, I respect what can happen if complacnent, not preping right, being sloppy, tired and never after (if I did) drinking or using meds not used to. Just shop safety thing that has been drilled into me at Bill's and previous shop. This sort of stuff will also in my opinion and drilled into me by Bill can and will effect concentration and your work product, particularly in the small detail work. Sorry will get of this probably not needed bandwagon. I am sure all of you do this anyway and not meant to offend intellegence of you folks in anyway. Now onto process.

Once the metal slats,starts to steam, start slowly, but steady cranking down the waist. Got to think once slat is steaming water sides are ready to bend, so don't want to take to much time (don't want to go real fast either, again doing it and getting familier with your bender will help dictate cranking speed). Once the waist is seated at bottom and snug to form stop. Don't try to over tighten the thing. Want it solid against form, but trying to much tighting may cause a problem.

Once waist is done, get the ends down and and secure (I usually do the neck end first, but that is out of habit. It may or maynot matter)Want to get the ribs all the way to bottom of form.

Once the timer stops, I don't do any further heating as don't want to chance the scorching of wood. The time we have it in the bender and wood is bent seems to be good, we did what we wanted to do, bend the wood to form. We do now leave the side in the bender for 45 min. or more, at least until the slat is very cool.

Take it out and put it in a mold, clamping rib to mold, so rib keeps shape as it cont. to dry and wood settle.

I personally think after using it, the bakers parchment helps with the burning issue, and is better for keeping heat distributed even.

Haven't read or investigated if this is true with science or experiments, just a thoughts and opinion and how we do it. We use alot of figured maple and other figured woods. Boss must of after many years and guitars come up with a good system.

I know it works, and we are not spending alot of time fixing or other problems with ribs after bending. Way I look at it, spending less time and with problems there, and still have very good, clean properly bent ribs, is less time in the whole process and doing other things.

I used to use parchment - but only with stainless slats. Now that I use non stainless spring steel, the foil is a must to prevent staining.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

we use spring steel and little or no scorching, discoloration or that stuff. maybe we have stainless spring still or someother kind of metal. won't go back to foil though, which most time had some funky thing in it. goes to show different outcomes with different folks. anyone ever just soak the wood up a bunch and put them in a turkey frier made to steam water, then with a radiator hose that goes to a locker type thing and steam them until floppy and then just put them into mold to dry.

Back in the early 90's when I had a tour of the Vancouver Larrivee shop, they used a steam box and heated form to bend their sides.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

Oh and thanks to all for the detailed help, I will be sure to let you know the outcome of the new set of imbuia (sp?) sides.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

I've been bending sides for over 30 years.
In that time the Fox bender and Blankets have changed what I had to learn to do!
Thin most sides to .85 then get the pipe hot enough to dance water on then pay attention to what your doing!
Listen to the wood-if it's going to split it will give you quick audible warning!
or use the fox bender and go WOW I just bent some sides!
Take the time to learn how to bend wood over a hot pipe -just to help your learning curve !
Do not use great guitar woods-experiment with waste woods!
It is important to be able to bend woods by pipe for repairs -and you'll like the experience !
Mike Collins
www.collinsguitars.com

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Mike Collins

Thank you gentlemen for sharing these proven methods.

It is very helpful to a newb lime me to know there are so many different ways to aceive a side bend!

Tony, Thanks for the details. Very well written and copied to file!

Stan, It sounds like you have done some experimenting with good results which got my brain working a bit.

Mike, I am with you on the advice to try various methods. That is the only way I will find MY comfortable method !

Rod, Sorry for the hi-jack !

Jeanne, no apology required.

I agree it's good to learn to do things in the traditional manor, I have bent 3 sets of sides on the pipe and have hated it every time. I have bent 4 sets of sides with the bender and 3 out of 4 have been as near perfect as needed.

Bending on the pipe I found it difficult to get the sides "curved" properly with out any flat spots, I do applaud those that can bend a perfect side on the pipe, your better than me.

Of course practice makes perfect, and I bet if I were bending sides every week, I would get very proficient at it whatever method was used, but alas, I am lucky to bend one set a year and if the stars aren't aligned just right and the wind isn't blowing in the right direction, I'm sure something will go a miss......

I'm sure with more practice and all of the great help I've been given here, I will become an expert after say, 100 sets of sides or so

Thanks again all for the help, muchly appreciated.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

Rod, coincidently, while most people start bending on a hot pipe, i found myself more attracted to the fox style side bender for the same reasons you mentionned so i started the other way instead and consider it way much easier than on the pipe also, i just applaud those who are good at it..

I steam bent my first sides with a home made steam bender with a kettle and built my side bending jig with bulbs and bought a blanket for no 2 and future builds, overkill?? No when you consider that some builder use 2 blankets!

Tony's advice is very good, i bought myself some foil for the next bending session and intend to follow his procedure to the iota, will keep you posted on my thoughts and of course will have piccys!

Ooooo, piccys, I love piccys

I too will be following the TK instructions very closly. I'm sure I didn't wait any where near long enough when bending my last set.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

   If I am offer , if anyone wants a set of my instructions I now have them in .pdf format. Email me with Bender or instructions in the subject line and I will be happpy to send you a set
john hall
blues creek guitars

You will find Imbuya bends like butter .. no worries its not a toughie like say padauk !!!

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I find you can 'feel' when the wood's ready to bend, even in a Fox bender. At least, that's how it went down with EIR and the more flaky/difficult Khaya I've done to date. Probably helps I don't really have a screw, and just push the cauls down by hand, and only then 'lock' them in with the threaded rod sections...