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Hi everyone looking for a high temp glue . My goal is to glue 4, 3/4in pieces of cottonwood to make a bending form for my style 1 weissenborn guitar. Just called dap weldwood and their 2 part plastic resin glue breaks down at 220 deg F , which is good for the laminated walnut sides at 275 -300 F. Will be using a 6 in by 36in watlow silicone heating blanket. Does anyone know of a glue that will break down at a temp over 350 F ???. Thank you

I guess I don't understand why you need that much temperature resistance in the glue to build your bending form. I use the inside cutouts when I make my mold - either glue four 3/4 pieces together or two pieces with some spacer blocks with Titebond. I'm bending somewhere between 250 and 300 degrees but the form doesn't get nearly that hot. I've built two koa Weissenborns - here is the side bending

My bending jig is much simpler than yours .I took the idea from an older GAL article by john calkin It is just 4 pcs of scrap wood., with a heating blanket and a wood caul. In the past I have used regular titebond and screwed the pieces to one another after 15 years there are gaps of 1/16 inch between all the particle board sections. It still works as uke bending form, Thanks for the pics, very nice jig. PS Probably the reason I have gaps is the heating blanket always goes on first on top of the the particle board , then the side. I don/t always use my temp gauge to decide when to bend . I do it when the wood seems most pliable.

Polyurethane glue has a higher melting point.

i don't use forms anymore because they take up too much room, but just use better wood next time and screw it all together. no need for glue. particle board isn't the best choice for hot work and glue isn't really necessary.

Screws would be the way to go.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

"after 15 years there are gaps of 1/16 inch between all the particle board sections"

After 15 years it may be the particle board picking up moisture from the air. I like to use plywood for the forms and just regular titebond glue. In another 15 years they will probably be "heirloom" quality!

Fish glue has a max temp of 500f. Protect it from steam!

When I make the mold for each guitar the inside pieces become the bending form. The Weissie was a bit tricky thinking about how to hold the head - I came up with something like this

Good looking work Freeman

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Joe Beaver
Maker of Sawdust

Ernie, are you building your Weissenborn based on that article by Calkin?

Firstly , this is my first venture into building such a large instrument I read jay rosenblatt/s 2015 article in asia and john calkins from 2010 gal, clay and others mentioned gaps in my bending form . I/m guessing they came from spritzing a mist of water over the years over unruly pieces that did not want to bend, and moisture must have gotten into the joints and the moisture cycling between wet an dry in our bsmt probably caused the gaps . I believe where we live here in the midwest is not a favourable climate compared to past shops in so. cal, an van bc. Freeman I used ideas from both articles Brent sent me a AA bearclaw sitka weissie top. john uses leftover sycamore and walnut for his top , next time I might try a sycamore top with a lot of beautiful ray fleck figure,jay used koa back an sides from notable woods, at 350-400$ that is way past our budget. I elected like john, to use a local grandview mo walnut from a sawyer friend. I cut it into 5 pcs to minimize warping. Like john I veered away from using the small tapered front end looks nice. But for a first build.I decided to make the sides a consistent 70mm w. The sides will be fitted into a tapered plywood front block with a seperate walnut headstock. Jay used ebony for the FB . I decided to keep it light and used a reclaimed old piece of light chocolate walnut. The Fret markers will be maple. I also skipped the rope a dope binding and decided to use a simple black plastic binding. I just finished gluing up the back and top , It was a real Pita . what takes me 30 seconds on a shooting board , turned to about 20 minute s each for the back and top. to strengthen the sides. I laminated a .022 piece of walnut veneer to a .74 piece of walnut for the sides . They will be further stiffened with laminated poplar on top and french birch ply for the back , recycled from a neighbourhood dumpster. Thank you all , for your tips, suggestions an photos , it is much appreciated. I kept the bending form real simple by gluing leftover cottonwood an ash using titebond an drywall screws. If I ever build another weissie, I photocopied the really nice bending form in this thread tht freeman built. The machine heads are small grovers. I also plan to butt glue the head to the body jus like calkin and use a long screw for insurance. And yes I have fish glue, but my at home tests showed it coming apart readily with moisture and humidity , I did laminate sides with PRG dap weldwood plastic resin glue , which I was told delaminates at abt 220 deg F

Yes. But, you're going to have to go to an epoxy. The service temperature range of polyurethane glues like Gorilla Glue is only -40° to 200° F.

If you search McMaster-Carr, they have a couple of 3M epoxies which are rated to 350° F. The closest is 3501. (-65° - 350°)

Loctite also sells epoxy which are rated up to 300° F. (1C and 11C)

JB Weld 8265-S has a max temp of 500°. Their 8270 epoxy is rated to 300° F.

If you want higher temps, you'll need to go to special high-temp formulations.

OK, it sounds like you have already built it so this might be moot. If you haven't assembled it yet, let me make a couple of suggestions. I would not do John's deep sides all the way to the head - if you read his article he has to buy a custom made $200 gig bag for it - if you build to the plans it will fit a standard Weissie hardshell case from Beard/Goldtone.

I built two at a time from the same pieces of wood - literally sister cuts. I have both the SM and GAL/MIMF plans - they are slightly different but basically the same. I braced one guitar based on those plans. John's article came out while I was building showing a completely different bracing scheme (Martin X brace with angled tone bars and finger braces. I figured I would try that on the second guitar



Everything else about the guitars is identical. We played the guitars side by side one evening, I gave my customer the pick of the litter, I would keep the other one. He chose the traditional braced one. Mine is fine, but I would have chosen his also



I don't understand John's drywall screw in the head - mine are glued to the sides and top and bottom. They work fine. However be sure that your tuners are on the flat part of the back of the head, on one of mine the curved part gets in the way





I agree with John about using a real saddle instead of fretwire. No compensation required. A tall bone nut, uniform 3/8 action. I like mediums for open D and bump the first up to a 14 or 15, the second to 17 or 18. I like an unwound third.

Have fun, these are cool little guitars

Hi freeman thanks for all your suggstions !!. No , I am just knocking out all the parts . I made the headstock an bridge seperately. Can still profile the sides and the front block as per your suggestion . I got 1, style 1 plan from mark fogelman and am using the als austalian luthier supply plan purchased via e bay , it is the same traditional style 1 plan . Never thought about the case you mentioned . Do you buy the case through a supplier ?? anyhow its great to get feedback before building. I might swap out the FB for ebony or rosewood, I will be using white plastic binding instead of the black . I have some maple and walnut for the rope binding, but that will wait for another build. What type of finish did you use ?. Thinking FP for the sitka top and tru oil or water base laquer for the rest . The water base does not pop the grain like tru oil does. PS I was planning to use the tradtional bracing plan, Does the top and back use englemann or sitka bracing ? or ??? thanks

I learned a long time ago to build to fit an existing case if possible. I bought my cases from Paul Beard, they were designed to fit his Goldtone Weissenborns. I don't see them on his page, best to call http://www.resophonicoutfitters.com

Apparently you can also get them at the big box guitar stores

https://www.musiciansfriend.com/accesso ... ctads-adid^221957295803-device^c-plaid^295577704042-sku^545185000000000@ADL4MF-adType^PLA

My guitars are 3 inches deep at the butt and 1-3/4 at the nut plus 3/8 or so for the strings and action. They sit on a nice little square neck rest in the case - I am very sure that John's design would not work. The bodies are 14-7/8 across the lower bout, 10 across the upper, 8 at the waist, and 37-1/2 overall length. I think you've got a bit of wiggle on those but the depth of the neck scared me.

Mine are all koa with simple maple binding, commercial rope rosette - I think that makes it a Style 2. I like to keep a theme going when I build a guitar so this has a koa headplate, rosewood f/b and bridge. I used maple for the "frets" and a bit of rose for the purfling to tie everything together. Simple.

Many Weissenborns are all koa or all mahogany, spruce over mahogany is also popular. I don't think you want a wood with a lot of complexity in it - after all these are slide guitars. I used spruce (probably Sitka) for the bracing and I only use lacquer for finish - even tho this isn't spectacular koa I did pore fill with Zpoxy which pops the grain pretty dramatically, then shot water based lacquer over that. I've only used TruOil for a couple of barnwood electric guitars - obviously use what you are comfortable with

A couple of pictures of the finished twins









Ping me if there is anything I can do to help

Thank you for the pic and the updated info Freeman , very nice Koa by the way !!! I have 1 question . Where did you get the commercial rope rosette ?? . I make my own sometimes and they are a lot of work IMHO. I cancelled my FB and messenger accounts but you can PM me and will reply promptly. Once again thanks for all the excellent info. I am eagerly looking forward to this build , but will take my time . Just cut out the top and back outline this morning . Gotta make a tapered side template before bending. Cheers

I've used this on several old timey guitars - I haven't yet tried to make my own.

http://www.lmii.com/products/mostly-woo ... y-purfling

Its the PFMQ1. Here it is on the Weissie

Thanks clay very nice rope rosette ! looked at the LMI it is a a good price considering all the labour involved in rope rosette/binding