Jma 1 bridge posts

[Infsub]

Hi all.
Just got my new JMA kit in the mail.

Doing a scratch build and the two tremolo bridge posts are dropping straight into the holes, no hammering or pushing needed. They come straight out again without any resistance.

Is this normal or have the holes been drilled too big? The lip sits on the body as it should.

I've never built a guitar with a 2 point bridge but have built many with bridge posts and they needed to be hammered in and do not come out easily, as major dents on my Prs kit will attest to?

Is it normal for the two point bridge posts to slide in and out so freely?

[Simon Barden]

No. Either the holes have been drilled too large or the kit hardware has changed and the posts supplied are now smaller than they were, but without the factory changing the hole size to match.

Send it back.

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Thanks Simon. I hoped you would be around as I know you have had this set up.

I will email them now.

[JimC]

I kinda wonder, if the lips are big enough, about doing what I did with my ESB-4 and embedding the posts in epoxy. I blocked the ends of the posts with candlewax so the glue couldn't get near the threads. In view of issues with mislocated post holes there might be advantages in being able to locate the posts exactly where required. You do need to be comfortable with epoxies though, what I used was a long way from the stuff that comes in tubes. I do note that I wasn't very comfortable with that as a solution at the time though.

[Simon Barden]

These have lipless inserts. They are also normally a bit smaller in diameter than the inserts for T-O-M style bridges and stop tailpieces (because of the trem cutaway so there's not much wood between the post hole and the cutaway). You can see one here at the bottom poking out from the spring claw.

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Yeah it looks like that. It is lipless and the top sits level with the body.

My concern is the thimble part slipping in and out so easy, should it need to bite into the hole a bit or is that how they should be?

The hole is an exact size of tune o matic bridge hole (I tried it, in case I need a plan b.)

[Simon Barden]

It needs to be very tight in its hole. It should’t be loose at all. The forces on it aren’t quite as bad as a stop tailpiece, as the trem springs help keep it in balance, but any looseness and the bridge will wobble, which is bad for tuning stability. Plus it allows the insert to move up and down when the trem is used, which will cause wear within the pocket and it will become even looser over time.

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Out of interest Jim, what sort of epoxy did you use? I did flirt with the idea of using two part surfboard epoxy with some fibre glass mat fibres mixed in. The same method I use to glass in surfboard fin plugs.

Obviously I will await a response to my email but if I can't get another ash body replacement, I want option's.

Another idea is to drop tune o Matic thimbles in there (they fit snug) squeeze some C.A. or gorilla glue in the thimble and set the JMA bridge in there. That would still allow me to remove it if needed with out damaging the body.


Just hoping it doesn't come to that though.

Gutted I am not going to be working on it this weekend as planned but at least I am in Perth so an exchange should be able to happen pretty quick.

[JimC]

I used Gurit SP106 with microfibres as a filler. This is boat building kit. The specific brand of epoxy isn't likely to be too critical but I'd be keen on the microfibres. You probably have to buy them in large quantities but if you have a mate in a boat building shop you can probably beg a handful.

[Infsub]

Yeah sounds similar to how I do surfboard plugs. I have all that on hand. How has it held up?

Looking on Pitbull site they are now out of stock with this model both in ash and basswood, so if I intend to have this done by Christmas as planned it looks like it may be Macgyver time. ( Not for the first or I will wager the last time on a guitar build.)