What to do with a broken off screw?

[rickaddict]

Hey Paul-

The other day I was removing all the hardware from one of my Ricks to give it a thorough Zymoling, when much to my dismay one of the four little jack screw snapped off.

The screw snapped off about a mm from the surface of the wood, and the break was pretty flat. So I punched a dent in the center of the screw with a center punch and very carefully drilled the screw out with a very small bit. Once I got the tiny bit through the screw, I put in a larger bit and drilled it again. I had a couple of minor mishaps with the drill, but I did a good enough job that I can screw a new (same size) screw back into the original hole.

The problem is, I'm a perfectionist. The jack plate will stay on with the 4 screws, but the one I drilled out isn't as good as it could be. The hole is a little bit larger than it was before and I'm not very confident that I could tighten as much as I'd like to. The good news is that all of this is hidden behind the jack plate. But still...I'd like to plug up the hole and re-drill it. I don't want to drill it any larger and put a dowel in it, because I think that would widen the repaired area enough that it would no longer be hidden by the jack plate.

So I was thinking of a couple different products I've worked with in the past that I could carefully drip in the hole, let it harden, and then re-drill the hole. The first was a fiberglass repair kit (not Bondo) similar to one that I used around 20 years ago. I remember that I mixed two or more parts, into a clearish liquid that when it dried was as hard as rock (maple).

The second similarish product I remember working with was a marine product, a two-part epoxy called Git-Rot. Last time I used it was around 25 years ago. But as I remember, it dried very hard and could then be sanded or drilled.

Would you recommend going forward with either of these two products or something entirely different?

[jingle_jangle]

Stay away from that sort of thing. Bondo is too soft; it'll pull out and besides, it looks like Bondo. Git-Rot is an epoxy that goes the other way--it's too hard.

Here's what I do:

Sharpen up a small (1/8" or 3/16" diameter) dowel rod on a piece of sandpaper. Make it a diameter that will jam into the goofed hole, good and tight. Cut it off to about 1/2" long. Now you've got something that looks like a smaller-diameter pencil stub. Dip the pointed end into some gap-filling super glue and using a small hammer, while the glue is still wet, tap it gently into the hole until it won't go any more. Carefully cut off the excess with a side-cutter pliers, trim flush with an Exacto-knife or sharp chisel, and redrill to the proper location and diameter. Bob's yer uncle, hey?

[rickaddict]

I didn't say Bondo, Paul! I wouldn't get near a Rick with Bondo. The stuff I was talking about is a resin stuff that dries really hard...like maple... and could be dripped into the hole. I used it to put a snowmobile back together once when my buddy crashed it! I remember that the leftover resin stuff (in an Elmer's glue-like bottle) dried so hard it was like a clear little Elmer's glue bottle shaped rock.

Anyway...it seemed like a good idea to me, but I should probably follow the advice of the master (you ). But now my questions are:

1) Where do I find a dowel that small? 1/8" would still be too big, but I guess I could sand it down.

2) Does it have to be maple?

3) Gap-filling super glue...what exactly is this? Can you recommend any brands?

I'm a little worried because the hole is now an irregular shape. I don't want to drill the hole out any more because I'm afraid of the repaired area getting so large that it can be seen around the jack plate. The way it is now, it is totally concealed.

[jingle_jangle]

Sorry, Jeff...I somehow read "Bondo" and skipped into a spiel.

The stuff you mention that you want to drip into the hole is a polyester resin (Bondo is polyester resin + magnesium silicate to make it easier to sand and provide the bulk of a filler material). Yeah, it will fill sort of but it's also brittle and unless reinforced with something (like glass cloth) has very little strength. That's where the dowel/super glue idea is superior.

Any lumberyard and most hardware stores carry small dowel rods. They are made of birch, which is neither too hard nor too soft; birch is a bit softer than hard maple but should work out OK. I used to live in your neighborhood 30+ years ago; I suspect neither the hardware store on Diversey , nor the hobby shop on the next block from the hardware store, nor the lumberyard on Kimball, are there anymore, so the sourcing is up to you...

Read the rest of my instructions. The aim is to sand the tip of the dowel so it looks tapered to a point, like a pencil. Trial fit it into the hole and if you can jam it in and it fits tightly, then you're home free.

The gap-filling super glue I use is called "Zap-a-Gap". Hobby shop stuff. In a real pinch, you could use the kind that comes in little tubes at 7-11; if they have a thicker stuff, then that's even better. DO NOT use any "GEL" super glue though.

If you tap the dowel into the hole, and you've sanded a proper taper onto it, it will fill an irregularly-shaped hole, no problem. The pressure of forcing it into the hole with the hammer will cause it to compress and expand in the right places so it conforms to the irregular shape.

[rickaddict]

Thanks Paul.

We still have an occasional hardware store around here... And a few Home Depot's (not my favorite place by a long shot) and a Menards (a little better than HD), so I should be able to come up with something.

[doctorwho]

Paul, I used Loctite Super Glue Control Gel, # 01-30379, for the gap filling on my Epiphone Casino Revolution neck repair that you coached me through recently ... I bought that type because it says on the back, "Ideal for ... minor gap filling." Maybe it's one "gel" that's okay?

[teb]

Git-Rot, by the way, is a low viscosity epoxy resin designed for saturating rotten wood on boats and making it sound again. In reality, it turns it into an unsupported hunk of hard, brittle plastic that actually has little in common with boat wood (or guitar wood for that matter) in terms of strength, flex, stiffness, grain strength, etc. The cure for rotten wood on boats is to replace it - anything less IS less. In this case, filling a hole with brittle epoxy would not make a very good anchor for a screw unless you either tap new threads into it or mold threads into it by inserting a greased screw while it's still liquid and letting it cure around the threads. There are fillers that could be mixed in with it to give it some fiber strength (milled cotton fibers, linen fibers or glass fibers) but you would still need to tap or mold the threads. Just driving a screw into epoxy with a hole drilled in it generally results in broken threads or just a bigger hole from tear-out as the screw goes in. Paul's idea combines lots of tiny fibers to hold the threads (fibers capable of being compressed without shattering) and just enough adhesive to make sure that they aren't going anywhere. It will produce a stronger anchor for the screw. Save the Git-Rot for do-it-yourself dentistry, where it has more in common with the material you're patching.

[sharkboy]

Todd, why, after your remarks, am I concerned that six Rickresource readers are going to knock down a few shots of Jaeger, grab the Git-Rot and the dremel and start going at their molars tonight?

Oh, right, Rickenbacker players. Too smart for that.

OK, I'll put away the Dremel tool.

[rickaddict]

Thanks for the info Todd. This place is a great resource. I was thinking that if I went the Git-rot way, I might have to tap new threads because the material would be too hard.

I am now convinced to go the dowel route. It's a tiny hole, but I'll just have to sand and shape a dowel to make it fit.

[jingle_jangle]