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Hi,

I'm going to be gluing up the back sides of my new build. What is the best best glue for doing this?

Thx
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If you're having to ask about the glue, you should probably put the BRW aside for the future. I'm not sayin' use cheap wood for your first build, but you should have a little experience before breaking out the BRW. Mahogany, maple, or East Indian Rosewood would be good choices to get the woodworking chops down.

For joining the backs, HHG(hot hide glue) or Titebond Original is used most often, but PVA, CA, and epoxy are also used.
Scrape the joint immediately before glueing, that raises the surface energy and improves adhension of the glue.
Do NOT wipe with any type of solvent before glueing, that can bring more oils to the surface than it removes.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Thanks, Roger. I used to be a furniture maker so I'm comfortable taking my chances, though I appreciate your advice. Nevertheless, I will dang the torpedoes and try mightily for a good result. What's interesting and not surprising...I read on another forum that it was best to sand the surface and then wipe with a solvent, letting it wick away right before gluing. There are many opinions (some better than others, obviously), and I'm trying to sort out the soundest approach. I really appreciate your response.

Fish or Hide glue;
the open time of these two will allow the glue to seep
into the pores.
Titebond 1 or the new Ellmers Carpenter glue.

Mike

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Mike Collins

At the price of BRW these days perhaps Russian Sturgeon Glue (Isinglass) would be the most appropriate?

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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.

Thanks, Mike!

Yes, there's quite a few places that recommend wiping with solvent prior to glueing. A number of discussions here and on ther forums have concluded that for guitars, it's not a good idea, that's why I mentioned it.
I built quite a few pieces of furniture before I built my first guitar, and they are different! For furniture work, 1/16" is close enough for almost everything. For a guitar, 1/16" is not close enough for anything!

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Steven, I first got into guitar building after a few years of furniture making. Although some of the skills and techiques of furniture making are transferrable, there are a lot of new things you will need to learn. Also, as Rodger indicated, the tolerances for measurements, as well as perfection, are completely different.

Your first guitar may turn out great, but only if you take advantage of the available information and books on the subject, plus develop a perfectionist approch to each step.

Thanks Rodger. I am taking the long, slow approach to completion. No artificial deadlines. I actually worked with much tighter than 1/16" tolerances, but that's due to a selective-perfectionistic streak.

Thanks, Barry! I appreciate your perspective and will take it to heart.

I have no evidence to show what I am about to say is true and please disregard at will….. but,

Titebond, and many other glues, are well known for creating a bond that is ‘stronger than the wood’. That is not always the case with thin plates. I find that when thin plates are glued together they are not held as tightly as thicker plates would be. In fact the bond of the thin plate may break before the wood falls. I have tested that on cutoffs

We all know that starving a joint of glue is not an issue, other than with epoxy. I think what happens with glues, except probably CA, is that since the plate is so thin, say .150 or less, when under clamping pressure, the joint can be starved. I believe that since the plate is so thin, the glue just has to migrate .07 or so to leave the joint. The glue has to migrate much farther on thicker plates and tends to stay in the joint.

So, to help with the problem I spread a nice bead of titebond and put the plates together but with no clamping pressure. I leave them that way for 4-5 minutes then clamp as normal.

Anyway… it has worked for me.

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Joe Beaver
Maker of Sawdust

Sounds like a great way to spoil your hard fought jointery. I joint the pieces just prior to joining.

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Pat

[/quote]

1/16" ? Really ? I didn't know that.

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Cut to size.....Beat to fit.....Paint to match.

1/16" ? Really ? I didn't know that.[/quote]

If my work was + or - 1/16", I'd be out of business in a hurry, and setting up a table at the high school craft show.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

Yep, 1/64" is what I work to on custom furniture. 1/16" is usually ok for trim in a house and 1/8" for framing.

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Steve Smith
"Music is what feelings sound like"

Fortunately, a rosewood to rosewood joint is rare on a guitar. The only one that comes to mind is when two back plates are joined to each other without the use of a decorative strip between them. Or perhaps on rare occasion when a back is made up of three or four pieces.
Usually its mahogany or Spanish cedar to rosewood (linings, kerfings, front and rear blocks, head veneer etc).
As above, Titebond or fish glue is my choice for this.