Router baseplate for Skill with PC hole

[Albert Wagner]

I have a skill 1825 router. I want to make a new sub-base that will accept PC template guides. As best I can figure out from reading the PC has a 1-3/16" hole. In the American Woodworker book "Woodworking with the Router" they say that I can make a custom baseplate that will accomodate standard template guide bushings by boring a rabbeted opening using two forstner bits: 1-3/8" and 1-1/4". Is that extra 1/16" diameter, the difference between 1-3/16" and 1-1/4" really negligible for template guide purposes? I have found forstner bits for 1-3/16". I am strictly a woodworking newbie, so any advice will be greatly appreciated.

P.S. I know that sub-base blanks pre-drilled for PC are available, but I really want to learn how to do this. I bought a 2'x4' sheet of acrylic to learn on.

[Dave Falkenstein]

Check out Pat Warner's site for precision drilled router base plates. He has a wide assortment already drilled for PC bushings. He also has a kit for centering a plate for drilling, if he does not offer one pre-drilled for your router - click on "Router Sundries". The hole for the collar must be quite precisely centered if you expect to use guide bushings successfuly. See Pat's stuff at:

http://www.patwarner.com/

[Curt Harms]

Hi Albert

I did something similar with P-C routers. As Dave said, Pat Warner may offer sub bases already drilled. If You want the experience;) , here's what I did.

First step is to use the existing sub-base to locate the mounting holes. I used a "vix" bit thru the existing sub-base to mark the holes in the new sub-base, then drill them to size. I mounted a V bit in a P-C plunge router. Screw the newly drilled piece of Acrylic to the base of the plunge router. CAREFULLY plunge the running bit to barely mark the new acrylic. I drilled a small through hole on the drill press. An alternative would be to plunge a small (1/8") straight bit all the way through the acrylic. You need to be able to drill from both sides of the acrylic very accurately.

I don't have an 1 3/16" forstner bit so I used an 1 1/4" I think 1 3/8" makes the opening for the shoulder of the bushing on the bottom of the acrylic. Drill it deep enough, change the 1 3/8" forstner out for the smaller forstner bit, turn the acrylic over so you're drilling through the top and drill a through hole. This should fit the P-C bushings. To check my work, I put a bit barely smaller than the bushing opening in the router and plunge the bit through the bushing. It's easy to see how well centered the hole in the base plate is. I was able to get the bushing centered within 2-3 hundredths.

You could try this on a piece of plywood just to get a feel for the procedure, then use the acrylic. Hope this makes sense.

Curt

[Albert Wagner]

<snip>

I don't have an 1 3/16" forstner bit so I used an 1 1/4" <snip>

Curt

Thanks, Curt. The book I have supports what you did. Did you notice any problem with the slightly larger 1-1/4" hole?

[Curt Harms]

Thanks, Curt. The book I have supports what you did. Did you notice any problem with the slightly larger 1-1/4" hole?

I haven't noticed a problem. The 1 3/8" shoulder hole keeps the bushing tight. Lee Valley does have 1 3/16" forstner bits if I put together a Lee Valley order one day. I haven't used bushings that much. I use mostly bearing guided bits for what I do, flush trim, edge treatments and the like.

Curt

[Albert Wagner]

I haven't noticed a problem. The 1 3/8" shoulder hole keeps the bushing tight. ...
Curt

Ah! That's good to know. I hadn't thought of that possibility. Thanks again for your replies.

[Bruce Wrenn]

Bill Hylton's later book "Router Magic" has a better section on making sub bases. Carol Reed has a book on the router, but I can't remember the name, that covers making base plates. She uses transfer punches (a Harbor Freight jewel) to make plate using router base or old plate. I like to use a V-Groove bit in router to mark bit location. Just barely touch the plate. This leaves a nice tapered hole for centering bits. Remove marked plate from router. With marked side up, drill smaller hole alway through the plate. Turn plate over and lower bit (not running) into hole to register it, then clamp to drill press table. Remove smaller bit and replace with a larger bit. Drill recess. You might want to practice on some baltic birch first. Best of luck

[Albert Wagner]

Bill Hylton's later book "Router Magic" has a better section on making sub bases. Carol Reed has a book on the router, but I can't remember the name, that covers making base plates. She uses transfer punches (a Harbor Freight jewel) to make plate using router base or old plate. I like to use a V-Groove bit in router to mark bit location. Just barely touch the plate. This leaves a nice tapered hole for centering bits. Remove marked plate from router. With marked side up, drill smaller hole alway through the plate. Turn plate over and lower bit (not running) into hole to register it, then clamp to drill press table. Remove smaller bit and replace with a larger bit. Drill recess. You might want to practice on some baltic birch first. Best of luck

Thanks, Bruce. I have "Router Magic" also. Both books use a 1-3/8" for the rabbet and 1-1/4" for the actual throat. I suppose what really triggered my post was the fact that the actual PC throat that most template guides are made for is 1-3/16"; I was curious if that extra 1/16" diameter slop was a problem for routing with PC guides, and if so should I invest in a 1-3/16" forstner. Apparently the rabbeted 1-3/8" shoulder holds the guide tight enough. Thanks again for the reply.