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Message started by pahdawg on Jul 23rd, 2003 at 11:07pm

Title: Side bender??
Post by pahdawg on Jul 23rd, 2003 at 11:07pm
I'm new to this site as well as uke building. I'm currently finishing up my second guitar. I bend my sides using a Fox type bender I made from plans bought at LMI with a heating blanket. I was wondering if anyone here has modified a "full size" Fox bender to accept a uke size bending form, and still be capable of bending guitar sides?


Title: Re: Side bender??
Post by achock on Jul 26th, 2003 at 9:56am
Hiya Pahdawg,  
Good question, thanks for posting it.  We do have the same Fox bender here in the Hana Lima 'Ia shop.  And it has been modified to bend regular Uke sides.  I think there was no problem with that, but I'm not sure about still being able to bend guitar sized pieces.

I'll have to defer you to Ukeman.  Have patience, he will check in sometime soon.....


Title: Re: Side bender??
Post by ukeman on Jul 31st, 2003 at 5:29pm
aloha al...ok...a true universal fox bender eh!...You can down size a fox bender and use 2 light bulb sources at 350 watts per in lieu of the 3 bulbs ala fox...the set-up is the same with the springs, aluminum waist bar and veneer press waist clamping unit....ah  but a universal to bend guitar sides as well would be a bit of a problem in locating the light bulbs as a heating source....we cheated a bit and now use a heat blanket...welcome to the new world of technology...thus with heat blanket you could use the same fox style guitar bender and merely make a few slide in forms for your uke shapes making sure that the waist lines up in the same place as the guitar frames do...you may have to modify the frame of the fox bender so that the smaller uke frames will fit into the  current guitar bending frame ( you might have to install interior ledgers on both sides of the bender frame). Check out the hana lima.com website and make a bending unit like its shown ...just as fast as making a fox frame and now with a space age new heat blanket making various frames is a snap......hope this all makes sense...laters  ukeman

Title: Re: Side bender??
Post by Hana Lima Ia on Aug 3rd, 2003 at 9:06am
Thanks for the info Ukeman.  Click this link to view our instructions on how to build a sidebending jig:


Please post any questions or comments here!

Title: Re: Side bender??
Post by ukeman on Aug 27th, 2003 at 6:09pm
Aloha bending form guys! Just finished a bending form for a cutaway baritone ukulele. Now I can proceed with this uke and hopefully have it ready for the November Exhibition....working on the soundboard inlay this week!

The side bender is illustrated in the Hanalima.com tool tip section...Simply remember that the bender starts with the uke shape ergo a template of theuke is mandatory. Your sides will simply be the half shape of the uke with an additional 6 or more inches for the side heights....the width is the length of the uke template.

Check out the site and no scared try em out...its a fairly simple bending jig....laters ukeman

Title: Re: Side bender??
Post by ukeman on Oct 15th, 2003 at 12:04pm
aloha people...hey..just am in the throes of side bending for two tenors and 2 baritones..the baritones are cutaways and the sides being selected is deep curly koa kine stuff....so  adventures in tight bending radii huh!

Flash...finally got off my duff and experimented with blanket bending using an outer sheet of thin sheetmetal to :
1. Retain heat from heat blanket below side material
2. Compress grain from expansion and blowing out as she stretches.

Results:   Super nice bends and realitively painless.
Will now make a new bender using these principles and have it ready for the November Convention Seminars....
Come to the Convention and check it out!....ok I will have it ready...no worry!......laters  ukeman

Title: Re: Side bender??
Post by ukeman on Oct 17th, 2003 at 11:00am
Update on Side Bender with Compression sheet:

Overall results: very promising....worth making modifications and using this technique:

comments: Sheet metal outer sheet really holds and retains heat..the balnket does not have to be left on constantly....after bends are made..shut off and it will retain heat forabout 1/2 hour easily. Plenty heat...no burning, very little spring back.

Bends like a son of a bitch and really quickly so one must slow down a bit and take your time on the bend.

Results:  koa   highly curled bent with no problem as long as you resisted the temptation to bend quickly..this method bent 2 baritone cutaways with little damage and less heartache than any other bending method i've tried.

summary.....worth experimenting with and using for you bending needs with heat blanket......laters   ukeman

Title: Re: Side bender??
Post by hapakid on Dec 7th, 2003 at 9:02pm
Hi guys,
Some thoughts:
I just bent my first set of sides today, and used the hot pipe method. It's easier to do, and harder to do well, than you think it will be. After reading "Guitarmaking: Tradition and Technology", I went out and bought a piece of 2" iron threaded pipe with an end cap (about $7 at Home Depot) and clamped it in a vise which I set up outdoors for fire safety on some sawhorses. Then I stuck a plumbers torch in the back, with the flame barely inside the pipe, and started bending the mahogany sides.
The wood really moves in your hand! It's fun! You'll need a spray bottle to rewet the wood because every spot that touches the wood is immediately dry and must be wetted before getting it near the pipe.
Next time I do it, I'm going to get a smaller pipe, and possibly a bigger pipe and have them all ready to go. The 2" pipe was too fat for the tight bend at the waist on a tenor uke, and it was almost too small to get the gentle bend of the lower bout.  Finding a 3" iron pipe is hard, though, and I'm still looking.
One tip I learned was that you have to hold the bend to let it cool for a much longer time than it took to make the actual bend. The wood will start to move just 10-30 seconds after it hits the heat, but you'll need to hold it in the bend for up to minute or more while it sets.
I also made the mold that Denis Gilbert recommends, and stuck the bent side into it right after bending it. That forces the still wet/warm wood into the exact shape needed.
Don't be afraid to try. Works great. Jesse Tinsley

Title: Re: Side bender??
Post by achock on Dec 8th, 2003 at 12:52pm
Hey Hapakid,
Right on, I think you have the best mind-set... No scared try um!  The pipe bender gives you the most freedom, but you have to be better at controlling the bend.  Hehe but I agree, that is part of the fun.  

Even if you have a bending form, the pipe bender is still very handy for touch-ups.

Title: Re: Side bender??
Post by Jesse Tinsley on Dec 9th, 2003 at 8:09am
Yeah, hand bending on a hot pipe is good for those of us who are impatient and don't want to wait days for the other benders to work.  And my first uke is kind of asymmetrical, but you can fix some of that with touchups and lots of clamps during glue-up.
I've heard different things about how long to soak wood before bending. I've heard to do it overnight, two hours, and 15 minutes in hot water. What's recommended for mahogany?
Mahalo for hosting this forum!
Jesse Tinsley

Title: Re: Side bender??
Post by Jon Y on Dec 9th, 2003 at 4:13pm
Hey Jess
I have read the same, overnight, 15 min., all kinds of stuff.. sounds like you are as impatient as I am :).  I have bent  a few sides with the hot pipe method and really like it (cause I am super cheap and I had a pipe and a torch already). I find that I am able to bend mahogany almost immediately after soaking with a spray bottle ... well maybe not immediately but within a few minutes after wetting( I wet the wood fire up the torch and as soon as the pipe is hot enough bend away). The trick I find is the amount of heat  you use... too hot and the water just evaporates and you burn your wood  too cold and hum de dum dum takes forever. The right amount of heat will cause the water to sizzle and transmitt the steam through the wood causing it to bend and you may need to spritz the wood while bending also... it's the steaming action you want. When you get the right heat the wood will set really fast and there will be no need for the mold to hold it in shape. I have done this with a few other types of wood and it seems to work well. Hope This helps.
Jon Y

Title: Re: Side bender??
Post by Dave on Dec 28th, 2003 at 6:30pm
:-/  I just finished my first Uke.  I used Gilberts book as a guide and used the hot pipe method for the sides.  I am a woodworker from the furniture world and was wondering why not just steam the wood?  Does it affect the accoustic properties of the wood?  Cheers

Title: Re: Side bender??
Post by hapakid on Dec 28th, 2003 at 6:56pm
I just finished my first uke and I agree that steaming is the easiest way to bend the sides.  I even used the plug/mold form that Denis Gilbert suggests to hold the sides after bending on the hot pipe. But even after using the form, the side were not symmetrical, and I could see the practicality of the Fox bender, where every piece of wood bent is identical to the last one.
On the other hand, I like the asymmetrical look and I'm going to use it on my next uke!
Jesse Tinsley

Title: Re: Side bender??
Post by Jon Y on Jan 29th, 2004 at 7:54pm
here is the Stew Mac info sheet on bending sides it is too large to post.. I tried so you gotta go to the page here's the url   http://www.stewmac.com/shop/Tools/Special_tools_for:_Bending_sides/1/Bending_Iron/Instructions/I-0689.html#details

It's quite informative and has all the plugs for their product but still very good! ::)

Title: Re: Side bender??
Post by ukeman on Feb 12th, 2004 at 1:40pm
Aloha all!

Hana Lima 'Ia just finished two  classes of first time side bending. The sets we are using are some unreal partially guilted honduran mahogany and some wild dense figured mahongany as well. Not the easiest woods to bend for anyone not to mention your first bending attempt.

Hana Lima 'Ia uses a half shaped form bender that Asa posted on the Tool Tip section of our website.We use our heat blanket that puts out 4 watts a square inch, some blankets put out 2 watts a square inch so on a blanket about 5" x 30" you'll get 600 watts of heat or 300 watts dependent on the blanket specs.
The blanket is placed on the form and heated.
The piece to be bent is sprayed with water on both side surfaces, and its edges.We place the side piece on the blanket indexing the waist with the waist of the bending form, and align for straightness.
Hana Lima, for the first time, used an aluminum perforated sheetmetal 5" x 32" long that has a piece of 1" net x 2" x 5" block of wood fastened to both ends of the aluminum strap.
Start your waist bend and bend until waist caul is seated with actual waist area of the bender. Now we have cinched the waist area of the side between the blanket and the aluminum strap piece.
We now bend the lower bout area by pulling on the handle of the aluminum strap, which compresses the side piece being bent right nicely against the heated blanket. We use a scrap flat hardwood piece to work our bend from waist to end of lower bout all the while applying downward and rearward pressure on the side by pulling on the strap handle and compressing the bejesus on the sides...bends so easily you have to concentrate not to bend it too fast. A minute to bend the lower bout seems like an eternity cuz it wants to bend so quickly with the compression strap.
Repeat the same on the upper bout...really concentrating on moving slowly and use at least a minute of actual bending time.Watch the clock or you will bend too fast!
Leave the blanket on for 2 or 3 minutes, then spray the sides through the perforations on the aluminum strap and let heat for a few more minutes.You could turn the blanket off and walk away since the aluminum strap really reatains the heat.The 13 people in the classes were all successful in bending their sides without any problems, breakage or heartache...yup still stress and trauma thickened the air, but all were smiling in the end.
I got the aluminum piece via Tom Becraft, a wood teacher out of Hawaii Mission Academy and a furniture maker as well, the piece was purchased as a screen panel replacement for an aluminum screen door, so Tom brought this leftover piece which I cut with a pair of tin snips...so thin and flexible that think i could cut it with a pair of scissors.Mahalo Tom...yup, adding the wooden end handles is the key!
Good bending     ukeman

Title: Re: Side bender??
Post by ukeman on Mar 17th, 2004 at 1:28pm
hey pipe benders and electric blanket benders...I use both methods but I forgot to tell you all that with both methods I still use me trusty blanket as a heat source.
For form bending its wood on blanket and compression sheet over wood....

for pipe bending its any kine diameter pipe I like with the blanket draped ovah the pipe fo heat....no need torch or charcoal briquets or propane or soldering irons....   ok  laters  ukeman

Title: Re: Side bender??
Post by Tom Becraft on Mar 23rd, 2004 at 9:53am

Indeed the perforated aluminum screen door mesh does work marvelously for making a compression sheet for side-bending.  I've now used it for about 20 ukeleles in our school shop with both mahogany and curly koa sides. No more inconsistencies or breaking in the bending process.  The technique has worked flawlessly each time. Thanks for passing along the compression sheet idea.  It puts the stress where it should be, on the wood, not on me.  Tom

Title: Re: Side bender??
Post by kamano on Mar 23rd, 2004 at 12:35pm
Aloha eveyone

I get one question from a novice builder....wen using da heating blanket.. (on da form) do you leave the blanket on all the time you are bending and using the top bending sheet.?

Mahalo Nui Loa (from da hot kine Ariz.)

Title: Re: Side bender??
Post by ukeman on Mar 24th, 2004 at 10:39am
yo kamano...yup wen I bend the blanket is on....I have no on/off switch nor timer..plug in, plug out! So wen i bend its in...jes keep spray bottle handy cuz da steam aids the bending so need water for da steam....so spray away wen ya bend!....wen pau bend 2 or 3 minutes...I spray through the perforayed compression sheet and leave on for about 2 or 3 minutes den i spray again and unplug....leave em in the mold till the metal is cool...spray again and plug in for 3 minutes and spray and unplug...pau....but i leave in for a hour or so...since i not in a rush...longer in less spring back....wen ya put it into your holding mold.   .ok  laters keep dry in Arizona..ha!  get nice kine no rust american classics huh!   laters ukeman

Title: Re: Side bender??
Post by kamano on Mar 29th, 2004 at 3:09pm
Ano'ai Ukeman

Jus get some mina problems...kokua..  I am bending a soprano yuke and I am having problems wit da small deep upper curve of the soprano.  I am using honduran mahagony cut to 3/32...is dis too tick? I am using da jig dat you folks get in da shop tips.  I am new to bending but I am a wood worka (small kine stuffs).
1) how long soak wood
2) am I bending too fas ..im using your one minute time.
3) oh yeah I wen use da heat blanket.

Shoots....dis is da 3rd side I wen mess up.

Also...have you eva use da blanket as a pipe benda..?

I was thinking (oh oh a local thinking????) can try wrap da kine and bend da wood.  sounds interesting...is da blanket hot enough???   Phew...mo betta I go Kalihi fo da school...ok...den...I I like da 95 school...


Title: Re: Side bender??
Post by RCHawaii on Apr 15th, 2004 at 5:31pm
ukeman stated in a previous post that he uses his blanket with both methods-so, yep!

Title: Re: Side bender??
Post by ukeman on Apr 20th, 2004 at 12:12pm
yo kamano...ok if you going bend wid da blanket heres a good process.

1. form at the ready, calmp to your worktable.
2. Make sure your waist caul not supah big...1 and 1/2 diameter is cool.
3. Get your blanket ready and put em on top form.
4. Get one spray bottle and fill wid water.
5. Get a small wood scar for pressing down the sides 1x2x5" is cool.
6. Make one Compression sheet####
This is just one thin sheet of metal dats real flexible...mine came from Tom Becraft and he bought one screen door aluminum  panel insert from City Mill and had leftovahs so I wen cut me a piece wid da scissors 5" wide by about 30' long. At each end of the sheet I wen screw a 1x2x5 piece of wood to use as one pulling handle. This sheet is perforated! cool eh...can spray water in da pukas!
7. I spray the side to be bent all over back, front and edges.
8. The blanket is on..and on top my form..I spar the blanket to see if get steam..got, so ready!
9. Put the side in and align at the waist.
10. carefully put the compression blanket over the side and slowly clamp down the waist dowel.
11. wen almost tight check the sides wid one popsicale stick by lifting up the compression sheet and measuring how far in the side is from the edge of your form...make sue the lower bout and upper bout along the same edge aligns...now you will not bend crooked!
12. Adjust side and blanket and compression sheet and den tighten waist dowel.....now nuttin moves!
13. Taking long, no worry! Spray water under the upper and lower bout and move to lower bout. One hand is pullin on the compression sheet via da handle and the other hand is smoothing down the side beginning at the waist over the compression sheet....move da block side to side and advance 1/4' at a time down da form..pressin wid da block and pullin wid da compression sheet...oh  she bend easy eh.
14. Doda same on the upper bout side...even mo slo...no forget spry water once mo before you bend the upper bout....wen pau no can see nuttin cuz the compression sheet covers the bent side....you can spray water through the pukas in the sheet. i leave blanket on for 3 or 4 minutes...spray water and pull da plug.
5 minutes later I pug in for another 3 minutes and en pull da plug...will saty hot for 10 to 15 minutes...
15 Open one side...if the side piece lift up (spring back) spray and put em back in...should get small spring back and all is cool.....ho  mo long fo say dis den to bend da buggah...no give up...try dis....laters   ukeman

Title: Re: Side bender??
Post by RCHawaii on Apr 21st, 2004 at 4:02pm
Remeber the stainless steel rods and rubber bands fo da bridge? Well, I figure jigs need dual purpose right?

When making my baritone form today, I drilled 3 holes in my side bending jig to accept three 1/2" stainles steel rods (Leftover puter printer junk I "salvaged" -I gots 7 of em). I used metal door screen for the form sides doubled over (its what I had, and hey was free) and tacked in place with some old metal furniture tacks.

If anyone wants a pic lemme know-glad to take one and show it. I plan on using ruba bands again :D And no I'm not "that" cheap, but I use what I got. :D

I made my form like your plan on the link above (Thanks for that!) and not sure how I want to proceed next (Heck I amost made the form double wide to do 2 sides at once but nah mo betta I practice first lol)
I don't have a "heat blanket" but I do have a "heating blanket" for when I get sick (Which I rarely do) so I might see if I can put that to use :D Wish me luck lol. The other option is to soak the wood for a bit and use ammonia, that will work fine, but I hate that smell and course it gives ya pele nostrils roflmao.

Title: Re: Side bender??
Post by oglavyandtuglavy on Apr 22nd, 2004 at 7:45am
Hey everyone.  If anyone has bent sides using highly figured mango, is it similar to bending curly koa-or is it more or less difficult?


Title: Re: Side bender??
Post by ukeman on May 1st, 2004 at 5:00pm
Aloha Nick,

Bending anywood that's curly is an exercise in patience. Your mango will be similar to your koa...the compression sheet over the side to be bent really helps but its always slow going. Deep curls have a mind of their own. I have never been able to bend figured redwood as I suspect the grain formation is just too loose...the hardwoods are tighter and while still a presure situation they can be bent successfully be going slowly and deliberately.       laters  ukeman

Title: Re: Side bender??
Post by Rix on May 17th, 2004 at 9:17pm
hi all,
i have a heat blanket and i have been experiencing some bending problems. i have already broken three mahogany and koa sides.  i try not to force it and i keep spraying the water.  i keep hearing the use of a compression sheet. can one direct to a link so i can see how that works? i just bought some curly koa sides and really don't want to mess this one up.  

Title: Re: Side bender??
Post by Dominator on May 18th, 2004 at 5:05am
I have not used them yet but here is one place you can purchase them.  Others just use sheet metal or roof flashing material.  Good Luck,

Title: Re: Side bender??
Post by Rix on May 18th, 2004 at 8:18am
thanks dominator,
so basically i would use this sheet directly under the dowel and directly over the wood? im having a hard time conceptualizing how this would bend sides better than just using the dowels alone.  
i have a side bender like the one we see on this site by the way, with sheet metal in place of the mesh.  

Title: Re: Side bender??
Post by Dominator on May 18th, 2004 at 2:14pm
I have not yet had the oportunity to try this yet but I will tell you the same thing a great luthier has shared with me.  Starting from the bottom use the spring steel or flashing, then heat blanket, then wood to be bent, then another spring steel or flashing piece.  having the steel slats on both  top and bottom helps support the wood (hoping to prevent blow outs) and distributes the heat more effectively.  I hope to be going threw this very process soon.
Good luck,

Title: Re: Side bender??
Post by blackdog on May 19th, 2004 at 2:20am
Rix... yes, the wood is sandwiched between the blanket and the compression sheet. I couldn't find any of the perforated aluminum so I just went to the hardware store (City Mill) and got a roll of aluminum flashing material and made my own.  

Just curious, where are your sides breaking at?

Title: Re: Side bender??
Post by Rix on May 19th, 2004 at 8:09am
sorry i don't know the terminologies but my sides are breaking at the middle and at the top bend.  get it?  
man this is is so frustrating.

when you say that you made your own, do you just drill holes in the sheet?
is there an ideal gauge for the sheet?


Title: Re: Side bender??
Post by blackdog on May 19th, 2004 at 9:55am
So it's breaking at the waist (the valley part of the jig) right? How are you situating the blanket? If you lay it down to conform to the jig no heat will be in direct contact with the wood at the waist area for the first bend which might be part of the problem (?).  For me, the blanket is floating in the middle from the start of the bend. So when I put the wood on it is touching the blanket in the middle. I think the compression sheet helps a whole lot in preventing blowouts in the upper and lower bout areas (the humps on the jig)...the outside bends. Did you follow Mike's (ukeman) routine a few posts up in the thread? That pretty much sums it up.

Just ask for aluminum flashing at the hardware store. Yeah took me about an hour to drill 1/16" holes every 1/4" over an area of 4"x 20". I made jig out of scrap 1/4" ply with notches every 1/4" (same theory as a fretboard jig) and went to it on the drill press. Then I riveted scrap metal rod at both ends so that I can grab the ends with a visegrip when bending. This is the first time I used the compression sheet method and I like it.

I'm just starting to get back into building.  So I'll be using this forum a little too. I took Mike's class a couple of years ago...just need some refreshing.

Title: Re: Side bender??
Post by Rix on May 19th, 2004 at 3:44pm
Yeah, I think thatís it, the blanket was conformed to the jig so the waist had no contact, shoot. Alright, ill make the necessary adjustments.
thanks blackdog.

I know that thereís a whole wealth of information here, but itís hard to follow with all that uke building lingo.  

Title: Re: Side bender??
Post by ukeman on May 21st, 2004 at 11:44am
Howzit Rix.....
Another way to use the heat blanket on your bending form is to place the side to be bent on the form first...it will float over the valley of the waist form....den place the blanket on top the side piece. The blanket itself will provide heat as well as compression.

wid blanket on top no can see the wood you are bending.
wid blanket on top...cannot spray sides if dry out.

However...I know some awesome makers you use this method with great results...my theory is...try em all kine ways and the one that works for you is the one you will end up using......have fun    later   ukeman

Title: Re: Side bender??
Post by ukeman on Jun 2nd, 2004 at 11:48am
Aloha all! Gee I forgot this small tip! For all you heat blanket benders....do not forget the merits of the traditional pipe..you pipe benders know that the sides hold will less spring back when bent with the pipe. You blanket benders know that you can get serious spring back if the sides are bent too quickly and not left in the bending form long enough to set the newly bent shape!

A good tip is to pick up a scrap length of pipe 2 and 1/2 " od is cool and clamp this section on your work area next to your side bender...overhand about 6 inches worth and wen pau blanket bending you can touch up any problem areas with the pipe...yes the TIP, use the heat blanket and drape over the pipe for constant heat source and viola you got a traditional pipe bender to play with at no extra cost...hmmm the best of both worlds for the price of one....laters  ukeman

Title: Re: Side bender??
Post by RCHawaii on Jun 2nd, 2004 at 12:57pm
Thanks for the Tip!!!!
For thoise who may not know "od" ukeman is referring to is "Outside Diameter".  

Also F.Y.I. the properties of wood are such that many times I over bend just a little so the springback brings it to the desired shape. IOW since wood does have springback, if you bend a little more than you want, the springback will take care of that problem ...

Title: Re: Side bender??
Post by Mark Roberts on Jan 20th, 2005 at 4:16pm
Hi All -

I an reading that for side bending several people are recommending to first put down the thin sheet metal or mesh, tehn 2nd the heat blanket, 3rd the wood, and finally 4th another sheet of thin sheet metal.
It would appear that this layering method does not allow the wood to closely follow the shape of the side profile by the thickness of the heating blanket, since the wood is on top of the heat blanket.
Pictures I have seen of various guitar makers using the Fox -style benders ALL use (1) the thin sheet metal screwed to the form, (2) followed by the wood, (3) followed by the next layer of metal, (4) and lastly the heat blanket. This allows the wood to closely follow the contour of the form, and with the heat blanket on the outside there is less scortching and the bending happens a bit more gradually.
I would appreciate your comments, if I have gotten the previous post wrong.

Mark in Portland

Title: Re: Side bender??
Post by ukeman on Jan 28th, 2005 at 12:22pm
Hi mark...nice talking to you on the phone...here's a reply to your question anyway!

On the Fox Bender original heat was provided by light bulbs in the form itself...3 places

The form frame was covered sheetmetal, although at the waist ponit of the frame a notch of about 1and 1/4" was made in the frame form sides to hold a aluminum bar which was in turn notched at both ends and hooked up to springs on each side to th frame where the veneer press brought down the waist caul to the frame.
This bar provided support under the sides to be bent along with waist caul pressure from the veneer press on the sides opposite surace. Way cool!

The side to be bent was placed twixt 2 sheets of sheetmetal attached at one end but open at the other to allow sides to be placed between sheets and for the side sheets to slip a bit when being bent. to uke or guitar shape.Two cauls were placed at the width of the form to mould and shape the upper and lower bends of the guitar and was held in place by spring pressure of 2 springs one on each side of each caul.

Ergo order was heat, sheet metal form, sheetmetal sandwich with wood sides as the meat of the sandwich and then caul pressure.

I guess with the modern heat blanket on a fox bender builders have modified the process a bit to either:
1. Heat blanket first, then sandwich
2. Sandwich first then heat blanket after.

I am of the blanket first, side next and I use a thin aluminum perforated sheetmetal to act as a compression sheild over the side to be bent.

Hope this helps   laters ukeman

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