Mounting a router. Need help.

[Gary Ross]

I want to permanently mount my router and dont know how to get it perfectly centered in the hole. The top is cast iron and aluminum and wasn't designed to have a lift insert. Its just a round hole in the top. I think it may be an old Geizzly but I'm guessing. I bought it used and I'm guessing it is old. Any ideas or comments are greatly helpful and appreciated.

[Earl McLain]

Depending on the size of the "hole", or if you have any inserts to fill part of it--using a centering cone would be best. This one (https://www.amazon.com/Bosch-RA1151-Router-Subbase-Centering/dp/B004Z8SM6M/ref=asc_df_B004Z8SM6M/?tag=hyprod-20&linkCode=df0&hvadid=310828259700&hvpos=1o1&hvnetw=g&hvrand=7868532786696397883&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9016200&hvtargid=aud-799727667774:pla-433123264002&psc=1&tag=&ref=&adgrpid=65583250281&hvpone=&hvptwo=&hvadid=310828259700&hvpos=1o1&hvnetw=g&hvrand=7868532786696397883&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9016200&hvtargid=aud-799727667774:pla-433123264002) is Bosch branded, but could be used in any 1/2" or 1/4" collet. According to an answered question at amazon, the outside diameter is 2 3/8".

earl

[Bill Space]

Why does it need to be perfectly centered? Never worried about that myself in my homebrew router table extension to my table saw.

The only thing I worried about was the possibility of the bit hitting the edge of the hole. So I made several different plates with different size holes. But turns out I just use the plate with the large hole in it, probably 3” in diameter...

Edit: Of course, if I were routing something small I would use a plate with a smaller hole, but for what I generally do this has not been needed.

[jeff norris 2011]

Why does it need to be perfectly centered? Never worried about that myself in my homebrew router table extension to my table saw.

The only thing I worried about was the possibility of the bit hitting the edge of the hole. So I made several different plates with different size holes. But turns out I just use the plate with the large hole in it, probably 3” in diameter...

Edit: Of course, if I were routing something small I would use a plate with a smaller hole, but for what I generally do this has not been needed.

Yes how the inserts fit is the only thing that matters. If it is just a bit off, it does not really matter.

[Doug Garson]

I agree, the centering cone mentioned above is for centering the base on a router so when you run it along a straight edge, like when making a dado, you get a straight line even if the router base rotates a bit.