The dreaded GLUE issue

[Gavin1393]

There seems to be a number of folk still experiencing problems with glue .

This is particularly a problem if you have a guitar with binding on it or if your guitar comes supllied with a flame Maple, Spalted Maple or similar Cap.

As this problem has been addressed in various places throughout the forum I have decided to try and condense all these bits of advice in one spot. I hope this helps!

Gav

[Gavin1393]

Quote from dingobass on February 18, 2013, 20:38
Hi Guys,
There has been quite a few questions arising around this topic. (see Wokka's ES, classic case of glue spread)

The simple answer is MORE sanding!

I have built three kits and numerous scratch builds with binding and have yet to encounter this particular problem, maybe I am lucky but I think it has more to do with my OCD when it comes to sanding.

I always pay more attention to the edges as this is the one area where most of us don’t sand enough.

This is a natural thing as we instinctively avoid taking too much off these areas.
Ergo, pay more attention to the edges and sand, sand and sand again!

[Gavin1393]

I have tried a number of methods to get rid of the $&@# glue....

I first tried the sanding method, but ended up sanding through the flamed maple cap which really pi$$3ed me off. It was just too thin at the edges.
Since then I have used Acetone / Clear Meths / denatured Alcohol to get rid of most of the glue and if still necessary I have then tried scraping the offensive stuff with a scraper / razor blade or similar. This seems to work to some extent, but I'm still not convinced it is the best option. I really believe we should send the manufacturer some Tarzan Grip and insist on them using this for the bindings. Otherwise, if we could find out what glue they are using it might help us figure out if anything is capable of removing it safely without sanding through the cap...

[Gavin1393]

I then had a discussion with a Pattern-maker. These are fellows who play with wood and wood finishing all day. It was suggested that i go out and get some wire brushes and follow a certain technique which i will explain shortly. These brushes are a little bigger than a toothbrush!

Quote from Gavin1393 on March 24, 2013, 18:30

Quote from keloooe on March 24, 2013, 16:20

And Gavin, 2nd brush attempt: http://www.bunnings.com.au/OurRange/...-Bhb3b/6114348

Callum, both the links don't seem to work, well, not on my ipad anyway.

So i have photographed my spare set for you!

[Gavin1393]

Quote from Gavin1393 on March 24, 2013, 14:46
...it is a set of three brushes a liitle bigger than a tooth brush but only just.....will set you back about $3! It was the ONLY thing that helped me.
I tried sanding and ended up sanding right through the cap despite being incredibly careful. That's just how thin the cap is at the edges.
I tried metho, turpentine, acetone....(don't try acetone near plastic!) and all it did was spread the glue or perhaps seal the wood so it wouldnt take wudtone over a wider area....so that didnt work.
Tried scrapers, the very best that SMac can offer...it was helpful but had the same issue of sanding through the caps.
A cabinet maker, far more experience than I and a professional when it comes to wood suggested the wire brushes. These scratch the wood enough to allow the wudtone to penetrate and colour the wood rather than allowing the wood to become polished and continue to reject the stain.

Steel wool will only polish the wood and leave you back at square one.

[Gavin1393]

Quote from Gavin1393 on April 3, 2013, 12:18

Quote from Bhull on April 3, 2013, 10:54
OK. Thanks for heads up! I might just stick with some sandpaper and elbow grease! bit worried I will scratch through the cap with a wire brush! Cheers for the advice

No, don't do that. You will sand and sand and the glue will remain. all you will have achieved is to sand away the guitar's Cap.

This wire brush trick was explained to me by a Patternmaker as being the best way to get rid of stubborn glue. Callum has probably not explained it exactly right and reading his post about glue 'falling out' I'm not surprised you would be reluctant.

What the brush does is to remove the glue without the need to sand away vigorously for hours. By sanding away vigorously you will end up 'polishing' the surface you are sanding. In turn, this puts you back in exactly the same position you were in with the glue; the wood won't take the Wudtone.

Here is why, in order for paint to penetrate the wood it needs to have 'pores' to sink into. Both the glue and the polishing seal off these pores and the paint/stain is effectively blocked leaving horrid patches of dark and light shades rather than a nice even finish. The wire brush will penetrate the glue, removing it and will 'rough' up the wood just enough to allow the stain in. You are not using a industrial grade product here, the brushes are slightly larger than a toothbrush and you need to apply just enough pressure to 'scratch the surface. If you break the plastic handle of the brush then you know you are applying too much pressure.

I have tried every other methos without success and I have had a number of models to build. In desperation I called the experts and this was their solution to the problem. It works....fortunately Adam has spoken to the factory and we understand that different glue and filler products will be used in future by them. If you do have filler problems simply remove the 'top layer' enough to fill with Timbermate and the Wudtone will sink into that no problem!

[Gavin1393]

Quote from Bhull on April 3, 2013, 20:16
Ok.

Thanks so much for your lengthy reply Gavin. Very helpful indeed.

I am not actually using wudtone, I just applied some regular old black timber stain (see the first pic below) and sanded it of almost completely (second pic) so that all I was left with was a little more prominent grain.

Now I intend on applying a thin single coat of this fluro coloured paint I have, so the grain is still completely visible, and then a LOT of clear gloss over that - in your professional opinion, do you think that the glue that is left will be an issue when I apply paint to it ? or is it only an issue for stains and products like that ?

[Gavin1393]

Quote from Gavin1393 on April 3, 2013, 20:35
That's a good question. This glue sticks and doesnt like to let go. The issue I see is that if the glue is still there it is likely to come away at some point in the future as it isn't a stable finish if you get what i am saying.
These guitars can last many years and the paint job will deteriorate as the guitar ages through use and being bumped and banged around. Any paint over the glue will not be attached to the wood and therefore i expect it will be weaker at those points. So whilst on the surface it may look solved it really isnt a long term solution.
The other side, is that it will be difficult to level the paint job (cutting) with sand paper and wet sanding because the glue is flexible even though stuck! You might manage to polish the wood by doing lots of sanding and getting rid of the glue that way, but i do think removing the glue is a priority. You have a better chance in, my opinion, of a successful outcome with the glue gone, even though you have 'polished' the wood to get this result.

Hopefully DB sees this post and can add or disagree with my thoughts on it.

[Gavin1393]

Quote from Gavin1393 on April 14, 2013, 15:46
I have had another look at your body of the guitar and can tell you it is definitely the glue. I think you might need to redo the sanding job on the top. You will need to take extreme care not to sand through the cap.
Have another go with the steel brushes where the paint hasn't penetrated the wood. Follow the grain with the brushes as you scour the wood. Then to finish, lighty sand the wood with 180 grit.
Good luck!

Quote from dingobass on April 14, 2013, 16:07
OK, try Gavin's wire brush technique, going with the grain
Then give it alight sand with 180 grit paper and dab the Wudtone on.

Leave it to cure for two days and then dab on more, again leave it for two days.

Do not steel wool between coats until you have put the first base coat on.

[robin]

Thanks Gavin, it has indeed helped.

As my latest kit has a few glue, filler and repair patches this will come in very handy. I thought I might have to paint it instead of my preferred wudtone/stain finish. But I will give it the brush and Timbermate treatment and see how I go. It might take a little longer but by the end I shall have added some more skills to my repertoire. Love a challenge

rob