saddle slot

[Brian Farrell]

Rookie needs help. I am shaping a replacement bridge from scratch and need to route a 3/32" slot. Problem is, I have few proper tools and a budget of $0. I have the Cumpiano/Natelson book, and they describe a technique that I can try, drilling holes with a drill bit along the length of the slot, then chiseling away the excess, but I would have to get a 3/32" chisel to scrape the bottom of the slot flat. I also have the dremel plunge router base, but the smallest bit I have is 1/8", and I'd really like to make this slot 3/32. I can get nice perpendicular holes with the dremel router, using it as a drill press, but scraping the bottom of the slot to make flat sounds difficult. Anyone used this technique with success?
I'm thinking of using the dremel grinding/sharpening tools to make my own scraper out of the grip-end of the 3/32" drill bit, hoping to get it dead flat on the bottom and sharp.
Am I overlooking any other way to get a nice clean flat slot at this width?
Any creative ideas?
Thanks!

[onewent]

..aluminum bar stock or hardwood, thinned to width, with some sticky sand paper on the bottom? I use a thin file to touch up the bottom of the slot when I replace a saddle. Or, a thin chisel as a scraper..you could make a cheap scraper from an old screw driver of appropriate width. Tom

[Tim Mace]

Kinda scary but I think a lot like Tom....you could probably mount the self made item on an adjustable clamp/rod
and pull back and forth ....maybe on 2 suction cups across the slot area. In fact I may go make one now!
They also make large shafted Dremel like tools that work just as well.

[Jay Gordon]

Brian, I know you said budget of $0 but I think you are inviting trouble to try to create the slot without a 3/32 bit. You really need a tight, clean slot to properly hold the saddle. With extreme care, you could possibly scrape the whole slot vs. drilling holes and then scraping (too much opportunity for error in IMHO). The proper bit will help ensure a proper job, AND you will have the bit for subsequent bridge slotting since it's a commonly used size. If it were me, I'd somehow find the 15-20 bucks for the right bit from Stew Mac or LMI.

[FRANK]

hey brian where do you live maby you can hook up with a luthier?

[Brian Farrell]

Hook up with a Luthier? now what fun would that be? I could get the right bit, but I'm still not convinced that the Dremel Router option was the best. The router base i have is ok, but there is quite a bit of play in it. I used the router base and a 3/32 drill bit to drill holes along the line of the slot. Then chiseled away the excess with razor. In the process now of scraping it flat, and i'm feeling confident that all will be good. certainly took more time than some other methods, but where there's a will...
thanks for all the input

[Antonio Cotichini]

I use the Dremel with the right sized bit. The cost of the bit is just over 0$. But I made a base mask to use as a guide for the Dremel. It isn't difficult. Just find the proper inclination for the borders. Many passages, improving the depth. I also made a chisel, with a piece of brass, just to flatten the bottom if necessary. I'll try to send a pic of those simple tools whenever possible.

[Antonio Cotichini]

Here we are! The mask is hard plastic laminate on a hard wood base. The chisel is brass and the Dremel is....a Dremel! The guitar body is a dead one, just to show how the system works.

[Brian Farrell]

Thanks Antonio! I have that black base in your picture somewhere, but I've been using the larger plunge router base.
I need to find that black one.
is CA1 the bit i want ?
End mill, carbide, 3/32” cut,
1/8” shank, (upcut), 1 1/2” OAL, 1/8” LOC
????
Thanks again for the pics

[Donald A. Fortune]

Hey Antonio How come I like your "lil' jig for making a slot in the bridge??
Probably because it goes under the word "kiss" and that means "keep it simple stupid'
I like it sir---
Peace,
Donald

[Antonio Cotichini]

Really I can't remember if the bit is CA1, just ask in the hardware shop. As I said, you must pass it many times increasing the depth by small steps to avoid burning both wood and bit. Try to go half the maximum speed. Test it all on a piece of hardwood before going on the real bridge.

[Antonio Cotichini]

Well, Donald, if I ever had the first idea to be a genius, I'd licensed my tool! But, as every honest luthier-repairer, money isn't my goal, just the fire of passion! So I send a couple of pics more. One is a better view of the Dremel with its multi purpose attachment. The other is the reverse of the base I made, to show the moquette I cut, to flatten it if there's a pick-guard.
The only problem comes if the bridge border on the sound-hole side isn't flat. But with a bit of patience....
Peace to you too.
Antonio