Gluing on the bridge but the wings won't cooperate

[nkwak]

OK, attempt #2 was a bust. The wing on the treble side popped up and a test with a piece of paper slid underneath showed me that the entire bridge's bonding wasn't that good. On the positive side I was able to take the bridge off by flossing at the bond with that paper and using no heat whatsoever, though a couple cedar fibers came up too - but nothing major. I just have to clean up the area and order up some more hide glue granules.

[nkwak]

Ugh. After 2 days under pressure the wings still popped up after only a few minutes under full string tension. What am I doing wrong? I'm following the directions as close as I can and not overheating the glue and IIRC I may have added less water than LMI called for. Is it my jig or because I stained the bridge?

What should I do? Should I heat the bridge and wick more hide glue underneath or just pop the bridge off completely again then clean it up and use Titebond?

[Darryl Young]

Did you stain the bottom of the bridge where the glue is applied? If so, what kind of stain did you use?

[nkwak]

No, just the top. FWIW the wings are pretty thin though; much thinner than either of my factory built guitars. Even when I was sanding the underside of the bridge, the wings wanted to curl upwards.

[Darryl Young]

You may want to try a different piece of wood for your bridge if the wings want to curl upward even before gluing. Think of it this way: The bridge is the stoutest brace on your top. It would normally help define/support your top radius. In your case, your bridge will be trying to pull the radius out of your top if the wings of your bridge want to curl upward.

Pick a well dried, stable piece of hardwood for a bridge. I'm sure many woods will work but maybe use walnut/maple as a reference and don't choose anything less dense (but you can go more dense).

Alternatively, you could get a good bridge or a good bridge blank from John Hall or StewMac etc. Be sure you get the height bridge you want if you order a finished bridge. If folks sell you a Martin reject bridge, they use various heights and you may not get the height you want.

Another tip: when sanding put pressure on the rear of the piece when moving on the sandpaper (or said another way, keep pressure off the front edge). The front edge tends to "dig-in" and this helps offset that tendency. So when sanding braces or bridges you can easily oversand the front edge causing a reverse radius near the edges.

[nkwak]

Well, I'm giving it another go-but not with hide glue. I routed down about the thickness of a piece of painter's tape, cleaned it up with naptha and used enough Titebond to get good squeeze out. It's been 24 hours and I'm about to take the clamps off. I won't stress the joint until tomorrow though.

[Kevin Sjostrand]

Ohhh, you've been using Hide glue all this time? I would have suggested Titebond or LMI white glue in an instant. You need a glue here that will really bond with the wood in the way that these glues do. I'll be you will find success now.

Kevin