Bridge notcher photos (Modified by Kent Swafford)

[Ron Nossaman]

Well, here they are. There are a lot of ways to build something like 
this, and a good percentage of them would work. I designed this around 
partly what I had on hand, partly what I could buy without spending 
thousands, and what I thought I was capable of producing with the 
equipment I have in the shop. I started with an old router, and went 
from there


1100: The carriage runs on 1/2" rods, with linear bearings embedded in 
the Baltic birch sandwich everything is bolted to. The cutter and hold 
down height relationship is fixed, with both mounted on the slide rods. 
Since the slide bearings and hold down mount are very close together on 
the rods, it's quite rigid. An old die set from a salvage yard, and a 
pneumatic ram harvested from junked data processing equipment twenty 
years ago provide the lift mechanism to press the bridge against the 
hold down from below. The big threaded rods front and back are height 
adjustments for different height bridges.

http://tinyurl.com/7duwe

https://www.moypiano.com/ptg/files/attachments/5f/29/07/11/DSC01100.JPG


1101: Cutter (2" shaper, Grizzly), hold down, lift table, and the arbor 
I made out of a chunk of steel plate, a piece of water pipe, and a 
couple of bearings. Have you ever tried to find an arbor?

http://tinyurl.com/a2fkh

https://www.moypiano.com/ptg/files/attachments/9d/17/9f/f3/DSC01101.JPG


1096: Overview, left.

http://tinyurl.com/74r2o

https://www.moypiano.com/ptg/files/attachments/d4/f0/d0/3e/DSC01096.JPG


1095: Overview, right. The timing belt pulleys step the 25,000 rpm 
router down to about 6,000 rpm for the shaper cutter.

http://tinyurl.com/9bp9a

https://www.moypiano.com/ptg/files/attachments/f3/dd/cf/47/DSC01095.JPG


1098: This is a slam suppressor. It's used on thinks like big cedar 
chests and the like to let the lid down slowly under hydraulic control. 
Since I'm doing a climb cut into the bridge top, this prevents the 
cutter from climbing on top of the bridge and eating me. A very good 
thing.

http://tinyurl.com/cm62m

https://www.moypiano.com/ptg/files/attachments/c5/f6/f4/0a/DSC01098.JPG


1053: The pneumatic foot switch which controls the lift table.

http://tinyurl.com/bqx6l

https://www.moypiano.com/ptg/files/attachments/f7/d8/e0/df/DSC01053.JPG


It ain't pretty, but the silly thing works about as well as I could 
have hoped. Oh yes, the highly sophisticated cutter feed consists of 
grabbing the router handle, pressing the trigger switch with my index 
finger, and pulling against the slam suppressor resistance until the 
carriage hits the stop. Very high tech.

And there you have it.
Ron N