Best way to cut bridge slots?

[adamrobertt]

I just started a new job as a professional guitar tech (after about 10 years of tinkering) and one issue we're having at the shop is that bridge slots are difficult to start on a brass saddled bridge. The file tends to chatter and scratch the plating on the saddles. What are some best practices for cutting such slots? Any particular tools I should look for? Right now we're just using nut files and a .25 gauged saw. Thanks!

[HarlowTheFish]

A really nice triangular file will make all the difference -- they can be pricey, but the amount of time they'll save you will cover it in a couple of months. Also keep some kind of square jig that you can use to get the file centered properly where you want it. Start it out with the triangular file then move on to the nut files to get it to the right gauge and round out the bottom of the slots.

[andy_tchp]

I just started a new job as a professional guitar tech (after about 10 years of tinkering) and one issue we're having at the shop is that bridge slots are difficult to start on a brass saddled bridge. The file tends to chatter and scratch the plating on the saddles. What are some best practices for cutting such slots? Any particular tools I should look for? Right now we're just using nut files and a .25 gauged saw. Thanks!

Last time I did this I strung up the guitar with the new bridge (it was a TOM in this case) so the strings could be laid across the saddles and aligned/spaced right where I wanted to start the slots and tapped them down (firmly - moderate force) into the saddle top, to create enough of an indentation that the file won't wander when starting the cut.

For the chattering, can only really suggest varying pressure/speed, and ensure all files are clean (if they're clogged up with bone dust this won't help - I was surprised at how much junk my nut files retain).

You may need to go with low/minimal pressure and be patient as the initial cut takes shape before really leaning in.

[timtam]

Stewmac has some stuff on this.
https://www.stewmac.com/video-and-ideas ... -inst.html
https://youtu.be/Q8GHkouWD0U?t=180