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I thought I had this pretty well figured out. Apparently not.

My bridge blank is thicknessed to roughly the final thoickness (at highest point). I've got a jig on the table that mounts the bridge so that it won't move, and I route the slot with my Dremel, set in it's jig. I take repeated passes with a 1/8" bit in the Dremel, lowering the setting so that the channel is gradually lower. Dust removal (vaccum) close, to remove ebony dust and keep the channel clear.

Either the screws on hte Dremel mount loosen themselves, thus skewing the angle of the Dremel, and 1) taking a nice divot out of the side of the nice channel I've carefully made , or, once it gets deep enough the bit grabs the sides, causing chatter, and 2) it takes a divot out of the nice channel I've made.

Anyone use a laminate trimmer or a router bigger than a Dremel for this, or a table mounted arrangement?


Thanks.

I have had similar experiences - especially at the slot ends where I tended to go too far on occasion and the bit would grab.

The only solution I've come up with is to make sure there is no play in the jig set up and keep the length of bit out of the chuck to the minimum needed to get the slot depth. As I approach the slot ends I go very slow and listen for when the bit first touches the end and immediately stop.

Even doing this and trying to be careful, I still get the bit grabbing once in a while and wrecking the slot. Bugs me to no end.

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

laminate trimmer for me.

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Rob

Ditto on laminate trimmer. I think the Dremel isn't rigid enough. Also, a spiral bit might be better with the Dremel, less likely to grab, causing chatter.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

I use a Bosch Colt and a 1/8" spiral upcut bit. I route mine after installing the bridge to insure correct intonation.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Router table and fence with a hefty PC router for me, straight 1/8" 2 flute bit, 2 passes for a depth of .200". Doesn't get cleaner than this. I use an acrylic jig to position the bridge on the guitar. A Dremel seems inadequate, minimum would be a good laminate trimmer for a precision job, better yet a heavy router.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Dremels are too small for this operation, IMO. My setup's built around a Bosch Colt.

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https://soundcloud.com/jeffreylsuits/he ... -runnin-13

My setup is very simple, a jig to hold the bridge, PC laminate trimmer with 3/16" bit (I use a wide saddle)....2 passes and it is perfect.

Greg

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Gwaltney Guitars

Thanks all. Great feedback.

Yep, sounds like a good excuse to buy another router!

At any rate, the Dremel's inadequate - I'll retool and mock up a better approach.

I have used all of the above methods. The heavy router works best if I am routing.

I have also cut several slot-thru saddle slots on the table saw. Very quick. You just need to make sure the bottom of the slot is flat. Most table saw blades will leave a little vee in the bottom of the slot. Just scrape it flat with a micro chisel.

EDIT: Never try the table saw method after the bridge is installed on the guitar!

Yeah, for that, you need a Skilsaw.

(Note on spiral bits in a dremel: The same runout that leaves a scalloped cut using a straight bit, causes a spiral bit to cut some interesting cross-sections. You may get a bell-bottom channel, or a wedge shaped channel, or a barrel shaped channel, and it will change every time you reinsert the bit!)

i do it on my drill press and a jig. i've had no tearout, and because i'm sliding the bridge in the jig, i can use stop blocks. plus, the depth is easier for me to control with the depth stop on my drill press. don't remember what bit, but i believe i mount a router bit in the press.

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brendan 3.0 new and improved, with better interpersonal subroutines

Update -

Bouught a Bosch Colt at HD today. Man, what a sweeet little tool. I'll never try a Dremel on this again. Absolutely no comparison... and that was with a straight bit - the only one they had in the right dimensions.

Thanks, all, for your help!

I've done jobs like routing saddle slots (on the guitar) with a Dremel. You do have to go at it gradually and use a light touch, and have a decent (basic) jig.

A good bit helps a lot.
http://www.micromark.com/FISH-TAIL-ROUTER-1and8-,7457.html

If you are using the Dremel HSS bits, they can be touched up with a diamond hone or small Arkansas stone.

Try cutting a slot by hand (with knife and chisel) some time, and then you will know that even working very slowly with a Dremel is relatively fast!

I do have an older (black) Dremel tool - I've heard that they may be a bit more solid than the newer tools (????)

John

I agree with Brendan I also use a drill press with one of stew mac's 1/8 " spiral bits. Basically have a fence and slide the bridge along it. I put tape on the front edge of the bridge then after I reoute the first slot you can add tape then remove it to get another pass to get a clean cut. You can then use the same set up change the bit to drill the pin holes and they will all be perfectly space from the saddle slot.


Brent