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a minor setback (read: holy sh*t i almost cried)
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Author:  brenbrenCT [ Fri May 21, 2010 7:27 am ]
Post subject:  a minor setback (read: holy sh*t i almost cried)
last night i finished shaping the nut and saddle on my first guitar. It's a rough little gem, sort of like courtney love: you know there's something beautiful somewhere in there, if you can just see past the track marks, rashes and cigarette burns.

Ok so it's not that bad. let's just say i learned A LOT. number 2 is gonna be great. *sweating*

But the bridge pulled up. I inspected what was left of the glue on the top and the underside of the bridge. Obviously i had an inferior glue joint. The bridge was not sanded to fit perfectly on the top. I used hide glue and probably will again. I had a bottle from a repair i did the night before.

So here's my plan, please chime in and correct me if anything seems suspect:

1. clean the top and bridge and resand. I was going to place a sheet of sandpaper carefully on the top and sand the bridge like you would for mandolin bridge feet. does this make sense?

2. make a fresh batch of glue (this is a duh, what a dummy, should have thought of that, thing)

3. My clamping was a bit of a fiasco. in hindsight i feel like i clamped the front half of the bridge well, but the back end not as well, and it was evident in the glue residue upon inspection. any thoughts?

This is a sitka spruce top with KTM-9 finish. I didn't mask, i scraped back. The bridge is ebony.

Thanks guys and gals

i'm with stupid :arrow: bren
Author:  Mark A Thorpe [ Fri May 21, 2010 7:38 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
I think your biggest issue would be that the bridge didn't fit the top perfectly, especially if you are using hide glue the surface needs to be a tight fit. Hide glue is not gap filling. So I would get a good fit and go at if again, I don't think you need to mix a fresh batch unless that batch is contaminated.
Author:  Chris Beebe [ Fri May 21, 2010 8:37 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
I’m sorry you are having trouble with attaching the bridge and I am sure you will find the help you need here on this forum; it is a great place to obtain quality information from men and women with a real passion for the craft. I have found this site to be refreshing for the simple fact it is free from low brow cussing and swearing. Lately I have found that many postings are including implied words that IMO bring the credibility of this forum down. I hate to be the potty mouth police but Brendan you could have made your point without the cussing. I understand that I am probably in the minority and do not intend to offend Brendan or anyone else, but there are a whole lot of forums where swearing and cussing are not addressed, let’s not bring that atmosphere here.
Author:  brenbrenCT [ Fri May 21, 2010 9:04 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
hey chris, any tips on the bridge problem?

thanks
b
Author:  Tim L [ Fri May 21, 2010 9:14 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
Bren,

Don't feel bad, the first one I made did the same thing after a couple of years. I agree with Mark about proper fitting and the fact that hide glue is non filling. Good thing about it is you should be able to reheat the area re-glue without any major problem. Make sure the area is scraped perfectly clean of laquer. Think mine lifting was helped out a bit by incomplete scraping on the edges.

Tim
Author:  brenbrenCT [ Fri May 21, 2010 9:20 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
Tim L wrote:
Bren,

Don't feel bad, the first one I made did the same thing after a couple of years. I agree with Mark about proper fitting and the fact that hide glue is non filling. Good thing about it is you should be able to reheat the area re-glue without any major problem. Make sure the area is scraped perfectly clean of laquer. Think mine lifting was helped out a bit by incomplete scraping on the edges.

Tim


that's another thing. When i was scraping the laquer, i was unsure whether i had gotten it all. I was reading W. Cumpiano's book, and he was warning about being careful not to scrape a hollow in the top. So i was trying to keep the area flat, but i couldn't tell if i was getting all the laquer off. Any tips?

thanks
Author:  Tom West [ Fri May 21, 2010 9:30 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
l I had a bottle from a repair i did the night before

[/quote]
Bren: Take a drink from the bottle and calm down...! laughing6-hehe Most likely the problem is fit. HHG only works on tight joints. Get a good fit and re glue. I like to check the fit with feeler gauges. I like to make sure a .002 feeler will not enter under the bridge. The bridge can be clamped dry for this if you want.I usually do it without clamps. Good luck.
Tom
Author:  Tim L [ Fri May 21, 2010 9:36 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
Quote:
Any tips?


Doesn't matter what I've tried there has always been some scraping involved, especially on the edges. I like to mask with Frisket well inside the footprint and then scrape the edges.
Author:  brenbrenCT [ Fri May 21, 2010 9:38 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
westca wrote:
l I had a bottle from a repair i did the night before


Bren: Take a drink from the bottle and calm down...! laughing6-hehe Most likely the problem is fit. HHG only works on tight joints. Get a good fit and re glue. I like to check the fit with feeler gauges. I like to make sure a .002 feeler will not enter under the bridge. The bridge can be clamped dry for this if you want.I usually do it without clamps. Good luck.
Tom[/quote]

unfortunately, i was drinking HHG. i don't feel drunk but i have a bloaty feeling and i can't stop eating oats.... ?

anyway...i will fine tune that fit, and test it with the feeler. awesome tip :)
Author:  brenbrenCT [ Fri May 21, 2010 9:42 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
Filippo Morelli wrote:
Don't beat yourself up too much ... it happens to many (me too!)

Sounds like you've already figured out your issues, from your original post.

1) should be a fresh surface
2) surfaces should mate well
3) glue should be preferably fresh (not old)
4) heat the parts
5) have an effective clamping mechanism (including bridge plate caul)
6) rehearse process to ensure it not only clamps up well but you know the steps you'll take to get there, so it happens efficiently.

Hide will sand. A bit of hot water can help with any spooge cleanup. You could sand to the top, but I wouldn't do it that way (especially with finish on the top now awaiting for you to accidentally screw it up by this step). If you have the matching bridge plate caul (which should be sanded in a radius dish to match your top dome, you can use that caul to sand the bridge.

If you provide more details on what you have (e.g. radius, cauls, et cetera) ... a photo ... folks more qualified than I will likely provide sage advice.


Filippo


oh i'll beat myself up all right ;)

i don't have a dish...yet. the bridge clamp caul was based on the cumpiano method. as was the bridge plate caul. i have four long reach c clamps that can get the job done, albeit with a tight grouping.
Author:  Tom West [ Fri May 21, 2010 10:10 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
Bren: Check out Charlie Fox bridge clamp...!LMI has them I think or very easily made. My favorite way to glue a bridge.
Tom
Author:  brenbrenCT [ Fri May 21, 2010 10:31 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
westca wrote:
Bren: Check out Charlie Fox bridge clamp...!LMI has them I think or very easily made. My favorite way to glue a bridge.
Tom


hmm. that is pretty much perfect for me. thanks!!
Author:  truckjohn [ Fri May 21, 2010 10:10 pm ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
My understanding is that Speed is also utterly important with HHG -- the open time is very limited... so you gotta have all your clamps and cauls immediately ready....

You may try a couple little bits of carpet tape to hold the inside cauls in place while you jockey the clamps.

Thanks

John
Author:  woody b [ Sat May 22, 2010 6:44 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
Quote:
When i was scraping the laquer, i was unsure whether i had gotten it all.


I suspect that left over finish, (as well as the fit of the bridge) may be your problem. If there's any finish under the bridge it will really weaken the glue joint. I use a chisel heated with a propane torch to scrape away the finish. At the right temperature the chisel will easily go through the finish, but stop at the wood. Obviously you need to practice on scrap to get a feel for it. I don't use KTM9 but I think it would work the same way.

You've already mentioned that you'll sand the bottom of the bridge to match the top radius. I also recommend heating the bridge so you'll have more working time with the HHG. I heat mine to 120 degrees F on a heating blanket. This give me plenty of time to get it set and clamped.
Author:  brenbrenCT [ Mon May 24, 2010 7:15 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
Success!

Things i did differently:

I sanded the bottom of the bridge to match the top.

I did a much more thorough job on scraping.

I heated the top and the bridge prior to gluing.

I also made a clamp jig out of a piece of steel flat stock. Drilled a couple holes for some set screws to hold the bridge ends down. I used a long reach c clamp in the middle of the jig. So basically the same as shown above. I will probably rebuild the jig and use wider flat stock and put some cork builtup at the back to put some more clamping pressure at the back. ( i used another clamp for that, but it was a bit of a last minute thing.)

Anyway, she has strings on 'er.

I was so surprised that my guitar sounds good. i don't know why, but i was. Needless to say, this is my first attempt and i'm extremely happy.

Things i gotta do better next time:

Neck relief
Keeping the parts clean and scratch free throughout the build
Better binding and rosette inlay
and all around better joinery.

thanks so much, you guys saved my weekend :)
Author:  Mark A Thorpe [ Mon May 24, 2010 7:49 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
That's what I like to see, success stories.
Author:  brenbrenCT [ Mon May 24, 2010 11:26 am ]
Post subject:  Re: a minor setback (read: holy sh*t i almost cried)
Todd Stock wrote:
Cool! Pony up with the pics when you get a chance to post.


ok, i haven't taken any close ups....which is good :)
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