Bridge Dimensions

[Kevin Sjostrand]

Darryl
Make the part of your jig that the front/flat side of the bridge rests agains stationary, and the part that will hold the back side adjustable, then it will accomodate any bridge you use or make; within reason anyway.
Mine I just use a couple of blocks of wood that I superglue down to hold the back side in place, then I just pop them loose.
I would not do it this way if I was in production mode, but to do a few, it is working just fine.
Make it adjustable!

Kevin

[darren]

Mine is adjustable, using a wedge. would fit a range of depths, made from scrap laying around, no less:

Image044.jpg

the wedge on the right is fixed to the vertical board, the one on the left would move 'up' to release the blank.

the red clamps are holding stop blocks to set the length of the slot, and the edgeguide attachment basically 'clamps' the trimmer to the vertical board.

I like to slot the bridge before any shaping is done - if i've screwed up the slot, the blank can be trashed without to much time invested. of course the idea, though, is to get the slot right the first time, but things happen!

Image042.jpg

this was the bridge for my multi-scale, so the saddle slot is pretty dramatic - 10mm. I plan on cutting new wedges for a standard saddle slope for the current 'project' :)

[Darryl Young]

Darren,

Using the edge guide to prevent the router moving from the fence is a good idea. I've been debating if I need something to hold my trim router base against the fence. Mine doesn't have an edge guide. I could always clamp a board in place on the opposite side of the trim router base against the fence.......that wouldn't be difficult.

Do you folks use a 1/8" bit if you want a 1/8" slot? Or do you use a smaller width bit and cut the slot in multiple passes? If you use a bit width the same as the slot width, you can't have any movement at all or the slot isn't in a straight line. If you use multiple passes, it's easy to get the slot a little too wide if you aren't careful.

[darren]

1/8" bit in 2 passes to get to full depth. You're right, there can be absolutely no room for the trimmer to bounce around, so find a way to sandwich your trimmer in between your fence and another board somehow.

[enalnitram]

Ugh...never mind me. I was awake too late, 2 nights ago. I was measuring my bridge in the right place, but it is 1 7/16". not 7/16". Duh!

[Darryl Young]

Ok, thanks for that measurement Martin. That gives me a good idea what I want to do to accomodate a Martin belly bridge.