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Because I’m lazy I usually by premade bridges. I currently have an OM on the bench which will be a lefty. Filling the RH slot won’t be a problem, but I have never cut a slot before.
Looking for a simple jig to achieve this. Any pics you guys have would be appreciated.
Maybe I don’t even need to do this, but I think the bridge will look out of wack with the extra skew.

Thanks for your thoughts,
B

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My memory is so good, sometimes I remember things that never happened.

Check out twoodfrd/s youtube video on cutting bridge blanks its a vy simple jig from BB , hes in hamilton. Its a 5 part series on restoring a mahog . harmony I forget which segment shows his bridge slotting jig , which can be used eiiher left or right with butterfly nuts maybe seires 5

I use a simple jig for cutting slots after the bridge is glued to the body but it could be easily adapted to an unmounted bridge by hot melt gluing the blank to a support board (and releasing it with alcohol after slotting it). Ted Woodford uses a similar jig for an unmounted bridge, so here is a link to his video:

https://www.youtube.com/watch?v=GyWy5bg5yFw

One advantage to using a separate support board is you can adjust the bridge slot in relation to the bridge so making a left hand slot is not a problem. I use a "stick" that has the proper offset to line up the router bit to the slot. And I mark the endpoints of the rout in relation to the baseplate on the jig.

Mine is based on Don Teeter’s jig I believe. I switched to using a guide bushing in place of the router base sides. I like its movement better. Seem like less friction during cutting. I also placed cork on the bottom to protect tops. Stops are simple wood blocks with a basic rod which is clamped in place via wing nut. They align with the router base (not shown). Clamp where you want the router to stop.

It doesn't get much simpler than this. I use this with my Dewalt 611, but the guide can be modified to whatever router you have. If I want to slot a bridge, before the bridge is installed, I temporarily attach the bridge to a piece of plywood, with a couple of screws thru the pin holes.

The little strips of tape you see on the bridge are placed to show the line of the saddle slot and the ends of the slot. These help with getting the alignment of the slot as well as the location of the ends of the slot.

Do the two screws bearing on the t. depressor angle the guide to accomplish a back angle in the saddle slot? I like it!

Those two screws are for raising or lowering the bass end, so that I can make the slot exit at the same depth on each end of the bridge. I actually have a permanent shim under the front of the rail to slightly tilt the saddle. The craft stick is there to keep the screws from digging into the mdfb.

Thanks James, this is exactly what I need.
It is said that imitation is the sincerest form of flattery.
Consider yourself flattered.
Thanks
B

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My memory is so good, sometimes I remember things that never happened.

Since I'm flattered, I will include a few more pictures. It is pretty easy to make once all the trial and error is completed.
I used this large knob on the bass end at first, but it blocked my view for lining up the router bit. I changed this to a small wing nut.

One of these at each end of the guide is locked into place and remembers my location. I can use shims here for small adjustments if needed.


Here it is on a Gibson SJ project. The slots for the spool clamps allow me to adjust it down to a parlor size as well.

If you want simple IMO this is about as simple as it gets. I made this jig some 25 years ago. I have never made a lefty before so that would require a new jig as it's not adjustable. But you just double stick tape the blank in place and run the router off the angled edge and it's done.

Here is mine. Not simple at all. Obviously, I took a few ideas from the Collins jig.

All of those fixtures are mind boggling. Why not just put the slot in first? A knife and a narrow chisel? I can see having fixtures for production, but even then; why can't the slot go in first?

Yes, I am an ignorant newbie to guitars.

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Why be normal?

Mine is mostly for repair when I need to move a slot, but it also works on loose bridges.

You are really asking two questions:

1. Why not slot the bridge before gluing it on the guitar?
2. Why not slot the bridge by hand?

As to the first question, lots of people slot the bridge before gluing it to the guitar. The downside is that intonation might be harder to perfect when you do it that way. Also, that doesn't help with repair work, such as needing to fill and then reslot the bridge, due to someone gluing the bridge on in the first place without enough precision (hint, hint). As long as you are careful, either method works. Plusses and minuses either way.

As to the second question, it is a pretty deep slot to cut by hand. Most of us would struggle to keep the walls of the slot smooth and vertical. A router is a better tool for the job, if power tools are on the menu.

Just my opinion.

I have cut them by hand long ago when I first started and those were slot through classical bridges which was easier. If you want a piezo then the accuracy is important. Plus a router makes it quick. For repairs, I just remove the bridge. But I can definitely see having one of those in situ jigs for repairs.

Really though, for me personally, I'd be afraid of jigging up a top and getting a router so close to it like that.

Thanks for all the help guys.
I agree with Don on cutting the slot, router is the way to go. I consider myself to pretty good with the chisel but a slot with good contact would be more challenge than I want, especially with multiple routers at hand.

I don't normally cut the slot, but buy premade bridges ( I know, lazy!) and place the the bridge with a carefully calibrated jig, keyed to the nut and saddle slots. Pic below.
If anyone can give me a good reason that this is not as an effective or accurate method of siting the saddle I’m all ears.
On a side note, what would the typical back angle on the saddle be?

Barry, that’s an impressive effort on the saddle slotter, bravo!

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My memory is so good, sometimes I remember things that never happened.

Nothing is wrong with the way you are installing pre-slotted bridges. That is similar to the way I do it when I pre-slot the bridge. I use my Saddlematic in the place of your fixture, but either will work just fine.

I don't have a preset measured angle for the saddle. I just did trial and error, shimming the front of the jig, until I got just a very slight back angle. I don't want much angle, maybe 1 degree backwards, I just don't want it straight up or leaning forward.

Back angle has been something I've been considering for a long time now but have not gotten around to doing it. I *thought I heard 2deg was the recommendation. There's probably some maths out there that could explain it.

What I do now is after cutting the slot I place the bridge using a steel ruler measured dead center on the 12th fret to dead center on the saddle slot in the center of the fretbaord and saddle slot respectively to 1/2 the scale length + .01in for compensation.

Some folks use tape on one end of the router bottom , when bridge slotting to get that 1- 2 deg angle

I don't know what the angle is but i just lay a scrap of purfling (@ .05 ") as a shim under the front edge of the bridge blank in the routing jig. It's worked fine so far. The bridge is being slotted before installing.

7 degrees. Or was it 7 1/2? Edit - its 7 degrees. Scroll to the bottom in the description - “break angle” http://rickturnerguitars.com/renaissance-steel

I still haven’t upgraded this to make a 2nd rail to lock in the router;currently rides on 1 rail.
I’m sure you could modify it for Steel string and slanted slots.

Focus on this jig is for the tilt back.

7 degrees is what I remember also. Two reasons given for it is that it resists the tendency of the saddle to be pulled forward by the strings (and break out the front of the bridge) and as the saddle height is changed the compensation changes - it compensates the compensation.

There is a camp that does not appreciate back slanted saddles because they make you have to compromise the set-up of the instrument. If you lower the saddle (or have to raise it) which are both very frequently done in the repair world and even in music stores doing simple set-ups you change if ever so slightly the "speaking length" of the string. This changes the intonation.

So... if you have to make a moderate height adjustment on a saddle in a climate that has winters where top domes fall or summers where top domes rise you should not have to make a new saddle or sacrifice decent intonation to get a decent set-up.

Seven degrees is what was discussed here over and over and over again over the years. I appreciate the logic behind redirecting the downward pressures but see this as problematic.

I'll add your saddle slot bottom is also critical in it's uniformity to how well a UST (under saddle transducer aka pick-up) will be balanced throughout the tonal spectrum. Our Collins Saddle Mill can do slanted saddles all day with a uniform bottom but I doubt that some of the simpler jigs that we even see here would be capable of doing it with tight tolerances that saddle slots should have.

There is also the issues of how well a saddle fits in the slot and how uniform the slot is throughout it's entire length. But that's for another post someday.

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Ann Arbor Guitars

Hesh makes a valid point that having a saddle slot with a flat bottom and a uniform width is more important than tilting back the saddle slot to keep the intonation constant as the saddle height changes. If you do tilt the saddle slot you need to calculate where the top of the saddle is in relation to the saddle slot and reduce the compensation at the top of the bridge by that small amount.
Fretted instruments with even tempered tuning have intonation flaws "built in" so at some point with trying to fine tune every little thing we begin chasing our tail.

I seem to remember that Rick Turner had an explanation that the tilted saddle was self correcting. I think it went like this: As you raised the action, the strings would need more compensation which was achieved by the tilt. The need for the additional compensation was that the strings would stretch more when you fret the higher string action. To me, it makes sense conceptually. In practice, who knows?