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Question For The Repair Folks Here
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Author:  Terence Kennedy [ Thu Apr 27, 2023 4:52 pm ]
Post subject:  Question For The Repair Folks Here
I got a 90’s American made Guild DR 52 in with loose binding. Big gap on the top treble side, smaller on the bass waist and both sides on the back.

It’ll go back but requires a fair amount of pressure. Even the smaller lifts take moderate pressure to seat so a repair will definitely be under some tension.

I’ve rebound older guitars, replaced segments, and pushed small gaps back but have not dealt with exactly this scenario before. An experienced repair friend has suggested loosening the binding to the tail block, regluing, and filling the gap with a binding graft.

Thoughts anyone? Woody? Hesh? John?

Thanks

ImageIMG_8572 by Terence Kennedy, on Flickr

ImageIMG_8573 by Terence Kennedy, on Flickr
Author:  jfmckenna [ Thu Apr 27, 2023 6:30 pm ]
Post subject:  Re: Question For The Repair Folks Here
If I can press it in place then I don't remove it. You can make clamping cauls in the shape of the guitar lined with cork to get enough pressure or use flat 'tape' cotton rope. The plastic binding will deform into place so tension is not an issue imho as long as it's glued well. I like to use CA for these types of repairs and apply carefully with a toothpick and work along inch by inch. But it's always a good idea to rope or tape the whol thing up to make sure it mates at the tail block well before gluing it.
Author:  Brad Goodman [ Thu Apr 27, 2023 7:49 pm ]
Post subject:  Question For The Repair Folks Here
My opinion, having repaired many guitars mostly Martin binding problems is not to press it back in place, loosen it all the way up to the heel block and then put a piece in.
The fact that it will actually be shorter tells you that it shrunk that much.


Sent from my iPhone using Tapatalk
Author:  joshnothing [ Thu Apr 27, 2023 9:34 pm ]
Post subject:  Re: Question For The Repair Folks Here
I have a Martin John Mayer OM in at the moment with loose binding at the waist both sides, front and back. Customer wants “perfect” or close to it, and neck angle is suboptimal anyway so I’ll remove the neck, rebind and probably spray too. Otherwise I would do the graft as recommended by others.
Author:  meddlingfool [ Fri Apr 28, 2023 3:44 am ]
Post subject:  Re: Question For The Repair Folks Here
Why is plastic binding still a thing? Are manufacturers taking pity on repair folk and keeping them in trade?
Author:  Hesh [ Fri Apr 28, 2023 5:23 am ]
Post subject:  Re: Question For The Repair Folks Here
Hey Terry, just saw this.

Dave does these for us and we do a lot of them since this is a very common Martin warranty repair we see these weekly.

We relieve any stresses before regluing and never try to force anything because it won't last. So Dave uses a variable temp heat gun that he's vetted over the years to have a very small thermostatic range meaning it will stay at the temp he puts it or very close. It's very easy to over heat and "smoke" the binding and then we are in deep doo doo.

So bindings of this era are malleable and when we heat them they can be stretched out in a manner that they stay stretched. So he heats to a specific temp, don't know if he even knows what that temp is it's a feel of the bindings thing and works the bindings until minimal pressure keeps them in place. He does not use tape of any clamping at all.

I think he uses CA for most if not all but I will ask him later today what he uses and get back to you. With very careful use of CA no finish touch-up has been required.

We do not clean old glue out and such either just warm, stretch, work and glue and it's good. His outcomes are excellent, you cannot tell it ever came loose.

I think he does modern bindings a bit different since the material is different. He swears a lot at the modern stuff.....

For Ed's question why do they still use plastic and I have a "suspected" answer." Two reasons, first bindings were originally intended to be a cushion against a bump not just another pretty face. And second traditional binding material is easier to work with than having to bend wooden bindings and all that sanding, etc. Anything they could do in the f*ctory that did not require skilled labor cut cost and increased production. Now they, plastic are tradition in say the Martin, Gibson, etc. world.

Anyway Terry when we have been asked about binding reglue before I seem to recall Dave not knowing the exact "number" of his heat gun temp so getting set-up with a heat gun for bindings may require 1) the gun and 2) scrap and 3) experimentation and dry runs to get going. He's marked his gun(s) we have two with a sharpie at the proper heat setting but the graduations on the guns do not list a temp just a scale of sorts.

More to come I'll ask him.
Author:  Hesh [ Fri Apr 28, 2023 5:31 am ]
Post subject:  Re: Question For The Repair Folks Here
Wanted to mention too that we are remunerated (paid) by Martin to do theirs and that means that any scope creep and we lose our arse.... So our approach is very specific to the exact job and minimalistic to that job too. We are not looking to have to spray anything or again we lose our arse and the scope of the repair and the extent of prior work on the instrument increases when it may not have to. No one wants more work on their instrument than they have to have to be whole again.

Josh has a different situation where more work is required and I can see us doing what he is doing too in that instance where the neck has to come off too.

Binding is considered a fairly minor repair and can be a minor repair with care, a skilled approach and not setting the dang thing on fire... :)

Lastly when one binding goes the other three waist bindings are suspect so be sure to inspect well for that too. It's easier to fix a minor pull up than when the whole sides comes off.
Author:  Clay S. [ Fri Apr 28, 2023 5:50 am ]
Post subject:  Re: Question For The Repair Folks Here
meddlingfool wrote:
Why is plastic binding still a thing? Are manufacturers taking pity on repair folk and keeping them in trade?


It's cheap and easy to install and usually lasts as long as the guitar will have a warranty. It also provides a tougher edge than wood bindings and is easier on the elephant population. I've been using it for a couple of decades and haven't had problems with it (not saying eventually there won't be). How many other factory produced items will last for decades without needing repair?
Wood and ivory bindings have stood the test of time, so for a handmade heirloom quality instrument might be a better choice.
Author:  Alan Carruth [ Fri Apr 28, 2023 9:05 am ]
Post subject:  Re: Question For The Repair Folks Here
Plastic binding is far easier and cheaper to install than wood, and you really don't need a better reason than that in a production setting.

Wood binding protects the edge of the top as well as plastic, IMO, but, of course, a hard ding from something with a sharp edge will damage wood more than it would plastic. In that sense, wood is less durable.

Many plastics shrink over time, sometimes through the evaporation of plasticizers. This also makes them more brittle. Nitrocellulose and cellulose acetate both break down chemically, and release harmful vapors (nitric and acetic acids) as they do, and are considered 'toxic' by museum curators. If the binding has shrunk enough to pull loose at the waist pulling it back just increases the stress on the glue line. Adding in a fill piece at the end helps with that, although it doesn't prevent future shrinkage.
Author:  Smylight [ Fri Apr 28, 2023 12:05 pm ]
Post subject:  Question For The Repair Folks Here
Terence, I had one of those satin-finished DV52 in the shop last year with a similar issue. Wasn't too keen on using CA ´cause I might have had trouble with touch-ups on this satin stuff if some got out. One of the good folks here (sorry, I can't remember who off the top of my head) suggested canopy glue and I'm happy to say it went very well. Of course the binding had to be gently heated and stretched, but we're a year later now and it still holds.

I've had to reglue all four sides, par for the course… of course Hesh was right about this.


Pierre
Guitares Torvisse
Author:  Woodie G [ Fri Apr 28, 2023 1:01 pm ]
Post subject:  Re: Question For The Repair Folks Here
Dr. Kennedy:

I would have replied sooner, but was on the road over to Greenridge in a very welcome rain storm (we've been much dryer here this year than usual... welcome back, El Nino!). Much of this has been touched upon, but worth reiterating:

- I suspect the binding and purflings are the usual Bolteron (ABS/PVC alloy), with a possibility of some vinyl purfling lines, and neither material glues well with anything other than an MEKP-enriched plastics adhesive or a good thin CA. If a fair amount of force is required to bring the binding into contact with the channel, I would suggest freeing the binding and loose purfling up to the neck pocket (top) or heel cap (back), then conducting a check for loose adhesive or other debris. If the neck must come off to free the binding, we add that to the bill, as any piecing in of material tends to be highly visible outside the fretboard extension/heel cap area.

- We tape the binding and purfs in using a strong, high-tack tape like the 3M green, then tack the binding/purfs in between the tape segment with BSI CA Super Gold thin foam-safe CA. If you are both quick and careful, you can get glue into the joint, then wipe off the excess towards the edge of the instrument... this CA is not as 'hot' as other CA adhesive, so other than a small amount of scoring on lacquer - and nothing at all on poly - cleanup is a very light scrape and sand with some P800 and 1200. We have found that touch-ups on Martin or other lacquer- finished guitars are often unnecessary if the repair is carefully done. The tape may be removed now and the joint inspected for spots where an additional tack is required. When tacking, it may be necessary to alternate between top and side as you work along the length of the loose material... and that may require rotating the guitar around to keep the fresh CA from flowing where you don't want it. Also worth noting that the amount of glue to tack things in is far less than you would think necessary, so more frequent, smaller tacks are better than less frequent, farther apart tacks.

- Do not allow the CA to flow into the tape... that may cause a hard edge that requires careful scraping or on low-quality tape, my actually glue tape to finish.

- When following up the tacking of the binding and purfs, work 2-3 inches at a time and keep a supply of fresh, clean paper towels handy for wiping up.

The usual careful scraper and wet/dry cleanup should allow a buff without additional clean-up. If you are lucky, the finish is polyester or polyurethane and any big boo-boos can be cleaned up with CA remover.

Good luck with the repair! I have a Thompson and a Huss waiting for me in the shop, so headed down.

WR,

Woodie G
Author:  Hesh [ Sat Apr 29, 2023 5:42 am ]
Post subject:  Re: Question For The Repair Folks Here
Well Terry Dave does not know the exact temp and he reiterated to me that he arrived at the set temp with scrap heating, testing up to the burning point and then backing off. His primary point that is very important is that he had a lot of trouble finding heat guns with a small range for the thermostat. Apparently the range that will soften the bindings but not set them on fire is only maybe 5 - 10 degrees. So a well regulated heat gun is required.

The two we use are still packed and we don't know where they are yet. We moved last month and our new shop is nearly done construction wise and then we will unpack. He did say what he uses heat gun wise is out of production so it may be time to try out the current crop and find who works well for this.

So sadly what we use is out of production and until we unpack it (find it...) we don't have a brand. When we do I'll let you know.
Author:  Terence Kennedy [ Sat Apr 29, 2023 9:25 am ]
Post subject:  Re: Question For The Repair Folks Here
Thanks a million for all the help folks. This is a great place. I’ll report back when the job is done.
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