Fish glue?

[Jason Brown]

Does anyone have experience using fish glue? What are the pros and cons of using instead of hide glue?

[Barry Daniels]

It does not have to be heated and it has a relatively long open time (meaning you can put the glue on one part and wait several minutes before attaching the second part). It dries crispy hard like hide glue. So it has a place in my shop. I use it for attaching the back and top to the sides. One downside to fish glue is the slightly messy cleanup of squeeze out. Also, there are reports of joint failure in guitars exposed to high humidity environments.

[Brad Heinzen]

I've used it extensively for years, and have never had any trouble whatsoever. As Barry said, it dries hard and crispy, and has long working and open times. The only downside that has had any effect on me is the long clamping time, which is easy to work around. I date the bottles when I get them, and don't use them for anything important after a year or so. It's the Lee Valley stuff that I use.

[Jason Brown]

Does fish glue smell bad? Does the smell go away after it dries? Does it creep a lot?

[Barry Daniels]

The smell is not bad at all. Creep is a term used to describe movement in a glued joint after it cures. Fish glue does not creep like that. If you were talking about movement when the glue is still wet, it is a bit slippery but not excessively.

[Todd Stock]

Initial tack is pretty good once the glue line is thinned. Cleanup is better than AR/PVA (i.e., Titebond), but worse than hot hide. Reopening a joint is a bigger PITA than hide, but not any worse than Titebond. I use it for long open time repairs and bindings, but prefer hot hide for everything else. Both fish and hide required better fitting of joint than Titebond, but show none of the creep that thermoplastic glues have issues with under load and moderate heat.

[Bob Hammond]

I'd research the various ways of using hot hide glue. Read the literature, and then experiment on your own time and materials.

[Arnt Rian]

My experience is that with fish glue, the parts will not slide around much when clamped, at least nowhere near as badly as with Titebond and the like. It labelled as a "High Tack Glue", with "...high initial tackiness.." etc. anyways, this is one of the things I really like about it. Your fingers will get very sticky during tasks like attaching bindings and purflings, so keep a bowl of water an towels around. As has been said, it is perfect for attaching tops and backs, and I also use it for gluing up neck laminates, which can be a bit stressful with hide glue.

I also like to use fish glue for certain repairs, where l know it will take some time, and perhaps a couple of tries, to get the parts lined up correctly. The extra open time can come in very handy.

[Stephen Neal Saqui]

After using Titebond professionally for 45 years I'm still wondering what people have against it. My plate joints have no visible seam, it cleans up easily the next day after gluing in braces. Easy to run a bead around gluing tops or back onto the sides. Dead on strong for most repairs. AND Creep? You look at anything I've glued and you'll wonder what do they mean by "Creep"? Suddenly one day Mr. Fox yelled out, "Throw that Titebond in the garbage!" and all the followers have been struggling with hot glue ever since. Mr Fox even admitted that hot hide glue is a pain.
I don't get it.

Fish Glue. I have a Manuel Reyes flamenco built with fish glue. all the top joints, lining, binding came completely apart. The guitar was made in '68...I'd sure be nervous to build a guitar that was going to fall apart while I'm still alive and building instruments!

Go buy a jar of Titebond. It ain't coming apart unless you want it to.

Go to https://sites.google.com/site/salmonriverguitars/
and see my guitars all made with Titebond.

[Todd Stock]

Ideal novice glue - long open time, tacks quickly in thin glue lines, cleans up at least as well as TiteBond (which is dreadful stuff for cleaning), and - unlike thermoplastic glues - will not creep at elevated temp. I don't use it for structural joints - strongly prefer 192g hide for general work and 315g for bridges and other high-stress areas, but nice for joints I want to easily pop loose with a little heat, such as fretboard extensions. Mario will likely mention that Elmers is an even better solution for that joint - so weak that the glue will act as a 'circuit breaker' with excess shrinkage of the extension.

I have a love/hate relationship with Titebond...love how it heat releases on a bridge, but hate the cleanup afterwards, and would not dream of gluing an instrument together with the stuff. A back brace reglue on a Martin made with hide is a 20 minute affair with most of the time spent waiting for the glue to gel...blow out the excess dried hide and any debris, heat the glue to 180 to get a little more open time, slather it in and around, clamp and then let it tack...wait ten minutes and clean up the squeeze out 'gummy worms' with chisel-tip popsicle stick and warm, wet paper towel. For braces glued with TB, there's the fun of cleaning out the joint to get to uncontaminated wood (dried TB is a contaminant in a joint), which can be done with careful sanding (slip the end of the strip into the joint, ease it through, then pull while applying pressure,,,repeat 10, 15, or even 20 times, then flip the paper and get the other surface).

Very common to find a raised ridge of separated finish on top at front of bridge...it's that thermoplastic glue doing what thermoplastic glues do...softening and creeping with heat. While I think TB is fine for highly stressed joints when the glue lines are thin, the bridge is one place where it's common to find thicker glue lines, and all it takes is one "...just gonna run in and get a Slurpie...darn...that hot redhead from bio class is trying to cool down by standing in front of the open freezer door...maybe I'll just stand here for an hour and admire the Pepsi sales display..." to heat up a guitar enough to start the bridge sliding. Worse yet, Martin could be pretty casual about maintaining a uniform .001-.0015 glue line thickness on their bridges, and once the glue line goes much over .003", it's time for a little cold creep.

All that aside, I used to give my students the choice of Titebond or hide/fish - they all build nice guitars, with the differences being repairability and resistance to elevated heat. These days, it's hide for structural work, fish for binding, and just a little TB for the joint I want to pop open with a little heat (the fretboard extension).

[Stephen Neal Saqui]

I have to say that I do use hide for restorative work on old instruments.

After removing a bridge that's been glued with Titebond, lay a moist cloth over the glued area only and let it penetrate. Cleanup becomes easy.
For building the skill comes in time. Knowing how much to apply for just a bit of squeeze-out is the mark of a good maker. Also good to use fresh glue. I've never used up a bottle of TB.

Proper fit and application are the keys to not having problems with any glue. I don't experience the problems Todd talks about. Poor joints such as a re-glued bridge are the exception when enough heat is there and it moves but the cause is usually poor work ie, too much glue.

[Todd Stock]

i wish my experience with Titebond was not quite so exhaustive...probably would not have such a negative opinion. I do like it for furniture, cabinetry, interior marine joinery (Type 3), and even some aircraft construction tasks like laminating buried wood longerons in composite fuselages...but after the first 1000 brace reglues, I noticed myself losing a little bit of patience with the factory builders that had it right up to the 60's, then opted for plastic glue. For removal of cured Titebond, I use De-Glu-Goo...minimizes swelling of the top and avoids dumping more moisture into the center seam joint. I agree - the cleanup on an open joint is easy...for values of easy that are about 10 times less easy than hide glue cleanup (brush away debris...wipe with warm, wet, paper towel...done)

[Stephen Neal Saqui]

I feel for you. Where do you live that you have done well over a thousand brace reglues? I've been repairing full time since '69 in one of the countries busiest shops and haven't had your luck...pretty amazing!

Thanks for the De-Glu-Goo tip.

[Todd Stock]

1-2 a week...3-4 braces per box...does not take that long. Apparently, I;ve worked my way into the 'repair guy of last resort/give it to Mikey - he'll eat anything' gig in the area, so lots of bad cracks, collapsing tops, and Gibson mystery glue. I work on referral only, so the usual ratio of 80% pickup swaps/setup work to 20% broken necks/major repairs is reversed for me. Lots of LG-2s with every brace in the box off...not one soccer mom string change in months. DC area have huge swings in humidity, so a flood of crack repairs with related bracing reglues still rolling in third week of June. 4-5 commissions a year and the odd spec guitar or two in the mix.

[Stephen Neal Saqui]

Very interesting! At The Blue Guitar in San Diego we did have brace failures but not to the degree you're talking about. When I sold the business and moved up to the Rocky Mtns of Idaho it all changed to dry problems....collapsed tops and cracks. I do warranty for Martin in three western states so no sopping guitars! Typically with braces pulling from dry in Gibsons I remove the braces with a pallet knife. Cleanup is easy. Martin braces ca break from the stress of the collapsed top but usually are hanging on where glued.

Different worlds we live in.

[Todd Stock]

Gibsons def worse, but I get a little bit of everything...L-48 and L-50 in yesterday with cracked tops and backs...the oddest was a '61 D-18 that was coated with salt and mineral residue throughout the box...sounded nice and the salt likely prevented terminal mold and mildew, but just the cleanup with deionized water was going to take a couple hours, plus reset/refret, and a couple cracks. Fortunate that owner had it on approval...back it went. No loose braces, which baffles me, given the exposure. Just cracked the back on an older travel guitar...2 of the 3 braces peeled away at the ends...above the bridge, but not tucked...not hard to see that coming.

[Mark Fogleman]

If you are of the age to have used jars of white paste glue and construction paper in elementary school you have experience with fish glue. LV's FG is made by Norland and you will instantly recognize the wintergreen smell of the paste glue of old. Norland has good documentation and case studies on their site: https://www.norlandprod.com/GelatinAP.asp

It doesn't need to be heated higher than room temp to use out of the bottle. I keep ~2oz/60ml in the fridge in a small squeeze bottle and freeze the rest. If I plan to use it I fill a coffee cup with hot water and place the bottle in it. In 5 minutes it's room temp and sits out the rest of the day. As said earlier, your joints need to be almost perfect for maximum adhesion as you're depending on a molecular bond more than a film bond. Voids with pockets of dried FG will chip like glass when stressed. I've had the best results by applying it thinly to each piece, allow it to absorb into the surface for 15 minutes or so, rewetting slightly with a spray bottle of water, joining and clamping. Much lower chance of starving the joint with clamps this way. I have a SWAG that this may be part of the problem with some of the reported problems people have had after using FG and not so much the humidity levels.

If you decide to try it you should mock up the joints in the woods you plan to use and test it. As far as disassembly, with a +500F melting point, you'll char the wood before it softens with heat alone. Small amounts of hot water in an insulin syringe/needle work well (but slowly) for me with no finish problems like steam creates. Steam is almost instant if you're in a hurry and can inject it deeply.

[Todd Stock]

I suspect some of the issues where folks see failures are the slower drying time and longer open time for fish versus other glues, and the need for better clamping strategies. Back in mid-2007, I looked at switching over to fish for some operations (linings; box closings), so did quite a bit of A v. B testing with 192g high clarity or Borland. Ultimately, I chose to develop the tool set necessary to use hide for what are longer open time operations and use fish only on a few non-structural joints.

There are some differences...pretty common for bridge plates to be clamped with hide or TB, then after gel (or tacking up with TB), clamps/go-bars can come off and a good cleanup done prior to re-clamping. With fish, you'll have to wait longer to allow the glue around the perimeter to dry enough to act as a barrier to air infiltration and separation along that edge. This may be one of the other reasons for failures seen with fish that might otherwise be blamed on high RH - we chalk a failure up glue starvation when the real culprit is clamping at pressures that thin the glue line, then allow air infiltration during either cleanup or clamp adjustments. The simple approach to avoiding the issue on area-style glue-ups like head plates, fretboards, bridge plates, etc. is to keep things clamped for 2-3 time longer than with either hide or AR/PVA prior to decamping for cleanup.

Same with bracing...if used to putting 5-6 cam clamps on 17" long brace, expect some issues with thicker glue lines with fish. I def found that all clamp pressure cones (clamp pressure propagates at about 45 degrees from line of application) needed significant overlap, so on a 1/2" tall brace, clamp center to clamp center was ideally 3/4" or less. Obviously, not a fun glue-up with cam clamps, but business as usual with go-bars. Same deal with head or bridge plates - vacuum or lots of go-bars or a really thick clamping caul if using cam or Bessey F-style clamps to get consistent pressure at the glue line. It's a challenge to get enough clamping pressure to thin the glue line beyond viability with go-bars or cam or f-style clamps used with thicker cauls, so def recommended.

[Clay Schaeffer]

"Thanks for the De-Glu-Goo tip" (MSDS 5% acetic acid)

Vinegar (acetic acid) works about as well.

[Todd Stock]

"Thanks for the De-Glu-Goo tip" (MSDS 5% acetic acid)

Vinegar (acetic acid) works about as well.

Having tried it, Clay, and white vinegar is super cheap and fine if the part can be dumped in a bowl, but cleaning off the bridge patch or other larger surface is really a lot easier with the gel-like De-Glu-Goo...old AR can take a couple hours to fully soften...that's a lot of wiping versus one application of DGG. Option is to cut a little patch of paper towel the shape of the bridge and dampen/spread with white vinegar, but my hourly is high enough that the cost in De-Glu-Goo is paid back several fold in reduced time spent on glue removal.

Sort of like GluBoost...sure...you can sit around and wait for an unaccelerated cure, or just accept a really bumpy surface with standard accelerators, but for someone that bills by the hour and is perpetually overbooked, the $13 for a couple ounces of the stuff is a bargain.