# Centering bushings on base plate



## p3auul (Jan 3, 2012)

I bought a set of router bushings to use on a dovetail template. There is a bit of "slop" when the bushings are in the hole in the template. I could center it by "eye" but is that good enough? Will they still make acceptable joints or would this create "slop" or joints that won't fit together?
Thanks,
Paul


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## dutchman 46 (May 23, 2007)

No! They should fit easily into the finger, but with no sideplay. What type, or name of Your dovetail jig, and the bushing might help.I have H.F. bushings, which are enexpensive, but they fit the jig well


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## CharleyL (Feb 28, 2009)

Your title refers to centering in the baseplate, but your question refers to the template.

To get good results the bushing needs to be centered in your router baseplate. Centering by eye is not good enough. To do this there is a centering tool available from the router manufacturers and also available from after market suppliers. It is basically a 1/4 or 1/2" precision ground shaft that fits into your router collet, plus a cone shaped piece with a 1/4 or 1/2" hole in the center. To use it you place the shaft in the router collet and tighten the collet. The other end of the shaft will extend through your router baseplate and/or bushing. Then you slide the cone on the end of the shaft with the narrower end of the cone facing toward the router. For centering the router baseplate, loosen the baseplate mounting screws and then push the cone into the center hole of the baseplate. The baseplate will be forced to center with respect to the router collet. While holding the cone tight against the baseplate, tighten the baseplate mounting screws. You can now remove the cone and the shaft. To center a router bushing in the baseplate, install the router bushing and then re-install the cone and shaft. Repeating the alignment process will now center the bushing with respect to the router collet. Tighten the router bushing and then remove the cone and the shaft from the collet. 

When using a router to cut dovetails with the finger type dovetail jigs it isn't super critical that the router baseplate and bushing be perfectly centered, but the orientation of the router with respect to the jig needs to be maintained to get good results if the baseplate and/or bushing are not perfectly centered. I put an arrow on the top of my router bases that I use for dovetailing so that I always point the router toward the jig the same way whenever cutting dovetails so that any centering errors are always the same with respect to the cuts. (If the bushing is off center with respect to the router bit and you change the orientation of the router during the cut you will create an error equal to this offset in your cuts). Some slop between the fingers of the template and the router bushing is normal and should not be a problem if the diameter of the bushing is correct for use with the dovetail template. Most of the better dovetail jigs are supplied with router bushings that are matched to the jig since many of the bushings sold in sets are not made to close enough tolerances to get good dovetail results.

I hope I have answered your question (whichever one you had) satisfactorily.

Charley


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## bobj3 (Jan 17, 2006)

Hi Paul

Many ways to get a good joint with the dovetails jigs and it's true the bit must be in center of the guide,that can be a pain sometimes so I'm a bit lazy I use a dovetail router bit with a bearing on it that way it's dead on all the time no guess work needed..the bit can be off 1/4" in the base plate but the bearing will take care of that error...note you can add a bearing to almost all dovetail bits..

Note the bearing on the bit is smaller in diam.than the finger slots in the template in the link below..it's not a big deal the bearing will follow the template and cut a very true dovetail joint parts..
like below
http://www.routerforums.com/project-plans-how/30687-ez-dovetail-jig.html

hope this helps a little bit, happy dovetailing .

==



p3auul said:


> I bought a set of router bushings to use on a dovetail template. There is a bit of "slop" when the bushings are in the hole in the template. I could center it by "eye" but is that good enough? Will they still make acceptable joints or would this create "slop" or joints that won't fit together?
> Thanks,
> Paul


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## p3auul (Jan 3, 2012)

*Darn! try again to eliminate "Template"*

Aw darn! one word wrong and the whole meaning changed!

I meant to say "router base" not "Template" I can see where you confused.

It seems the bushings are just a bit undersized so there is some slop when you insert the bushing in the hole of the base plate. So my original question was:

There is a bit of "slop" when the bushings are in the hole in the *baseplate*. I could center it by "eye" but is that good enough? Will they still make acceptable joints or would this create "slop" or joints that won't fit together?


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## CharleyL (Feb 28, 2009)

Paul,

When you rout dovetails with a template you should follow both edges of each finger slot of the template with the router and bushing. A U shaped path with the bushing touching the template through the entire cut. When you have finished cutting all of the slots, go back and repeat the cuts again to be certain that all of the slots have been cut cleanly and completely. You want the router to remove as much of the wood as the template and guide bushing will allow. On variable space templates like the Leigh D4R the amount of material to be removed between the fingers can sometimes be quite significant, requiring first following the edge of the fingers and then cleaning out the center area kind of free hand. The template keeps you from cutting too much, but you need to remove all that you can up to the limits of the template.

Charley


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## Mike (Nov 22, 2004)

Paul, the guide bushing should fit securely into the base plate, there should be no slop. Let's take the guess work away... measure the through hole. It almost sounds like you have a plate drilled for the larger Oak Park/Lee Valley style bushings.


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## p3auul (Jan 3, 2012)

Whew! I've worked with this thing till I'm blue in the face! The flange on the HF bushing was a hair to big so I chucked it into a drill press and sanded it till it fit. I took the router that I just bought from Sears and put the bushing on the baseplate. I put the dovetail bit in the router till it bottomed out and screwed the baseplate back on the router. Now the dovetail is up against the bushing and there is no room to adjust the bit.

I watched a video on youtube about General's EZ-Pro Dovetail jig. It comes with a router bit with a bearing on it so you don't need a bushing so I could use my old router. You can even use it with a router table. Has anyone heard of this one? It may be just what I need. 
Paul


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## gypsy (Jul 26, 2009)

Excellent explanation...just the information I was looking for!


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