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So I set a up a jig to rout my saddle slot in my nice new bridge I built, and it turned out somewhat like this:



The plywood jig I built ran on both side of the Stew- Mac precision base for my dremel. Everything on the tool was as tight as I could get it. The bridge was screwed down and could not move, as were parts of the jig. The movable parts of the jig were clamped tightly. I lowered the bit a little at a time, making multiple passes.

I went back and researched more on slotting bridges, and the Stew-Mac toot said to use a smaller bit than the slot (I used 1/16th), and then shave the sides in separate passes. So is this normal? The bridge is ebony, pretty hard, and I guess the small bit cannot help but chatter some. I guess I can try shave the sides and use a wider saddle now, but before I do that I thought I would ask if you guys thought I was missing something else.

thanks,
Damon

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Damon Wack
https://www.facebook.com/LindamonGuitars

Damon, I'd say that 1/16" bit is too tiny and it's flexing. I use a rather stiff 1/8" bit and make sure my Dremel is not loose in the bearings too. I also make around 4 passes...

Either that or you've got runout in the bearings of the dremel. I have a heck of a time keeping my new cordless Dremel form chattering when doing inlays and rosettes. It's almost like there's play in the bearings. I use a laminate trimmer for saddle slots because of this.

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Rob

Yup, Dremels aren't too good for this kind of work. I'm going to use my Proxxon on the next one.

Yeah, that was a thought as well. I use the same dremel for my inlays, in ebony, with the tiniest bit available from Stew-Mac, with no problem at all. I haven't used this bit much, so I don't think it's dull. I think because I took a deeper cut than the inlay work, it's perhaps biting off more than it can chew (so to speak!), and a laminate trimmer would be better for this kind of work.

thanks,

Damon

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Damon Wack
https://www.facebook.com/LindamonGuitars

Damon: Dremel not the best choice for this job. Also bit is too small for me. I use a 1/8" or even 3/16" and find them ridgid enough. I use a wide saddle,.200- to .200+. Also I have taken cuts seperately off each side to clean things up. I cut the slot in a drill press and my jig allows me to move the bridge to either side by using lengths of feeler gauge stock. Size of the slot is not really as important as having clean parallel sides and a flat bottom.You can make the saddle to fit the slot. You should be able to clean this up and make it work.
Tom

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A person who has never made a mistake has never made anything!!!

The bearing housing junction on some Dremel tools can have a lot of slop. You can take the Dremel apart with a Torx bit and put a small ring of shrink wrap around the Armature/Bearing in the correct location. Shrink it and screw it back together carefully to keep from stripping out the screw holes and the wiggle will be gone.