# Centering your router on a mounting plate



## Mike (Nov 22, 2004)

It is very important that your router be centered on your mounting plate. Many people sweat over this for hours remeasuring before they drill their mounting holes. The quick and easy way to do this is with a centering kit from Rousseau. These kits work with all brands of mounting plates that accept Porter Cable style guide bushings and they cost $5.

Step 1. You chuck up the centering pin in your routers 1/4" collet.
Step 2. Insert the disk into the center hole of your mounting plate.
Step 3. Remove the sub base plate from your router, set it and the screws aside.
Step 4. Install the transfer screws into your routers base with the points facing out.
Step 5. place the centering pin into the disk, position your router to face the direction you want it mounted and lightly tap the edge of your router with a mallet. This marks the locations you need to drill.
Step 6. Drill the holes, flip the plate over and slightly countersink them.
Step 7. Using the new screws that came in the centering kit attach your router and it is perfectly centered.

If you are using a plate that accepts the larger Oak Park style guide bushings you can purchase a centering disk and a guide pin from them. You can purchase transfer screws from most hardware stores or tool suppliers.


----------



## tomfitzman (Jun 25, 2009)

Thanks


----------



## falk (Jul 24, 2009)

Why is it important? The only reason I can think of is if you think you might remove it and put it back rotated, in which case it could mess up your pre-sets.


----------



## jschaben (Jun 21, 2009)

falk said:


> Why is it important? The only reason I can think of is if you think you might remove it and put it back rotated, in which case it could mess up your pre-sets.


Hi Edward,
I think Mike presented that with the assumption that the router *opening* was also in the center of the plate. I don't see why it HAS to be there but you want the router centered in the router opening. Primarily, should you ever need to use template guides with your table, the bit would not be centered in the guide effectively rendering the guide and template worthless. The other reason you would want it centered is if you are running a larger bit, it could strike the edge of your insert or opening itself, if your not using an insert.


----------



## falk (Jul 24, 2009)

Got it. Good reminding me that the router needs to be centered in the hole. My Milwaukee came with a centering jig for installing base plates, I'll have to see if I can use it somehow.


----------



## falk (Jul 24, 2009)

Oh, FWIW, I'm just making the mounting plate out of malamine. Is that a dumb thing to do?


----------



## jschaben (Jun 21, 2009)

Hi Edward, I dunno, knee jerk says no but I haven't got that much experience. 
Somehow you got to posting this under a "Sticky" which seldom gets read more than once. I'd try starting a new thread under "Table mounted routing". Go back to the Table mounted routing and drop down below the stickys. 

Most of the plates I have seen refered to are either phenolic or aluminum. I suspect the melamine and whatever substrate it has been applied over isn't going to be rigid enough until it is made so thick that you loose a significant depth of cut. 
Good Luck


----------



## Mike (Nov 22, 2004)

Good answers John.


----------



## dirkost (Jul 8, 2009)

Hi Ho: I don't know if one can respond to stickys, but I found the easiest way to center the router is to use guide bushing with a 1/4 inch hole and then put a 1/4 inch bit in the router. Since the guide bushing is the best reason for centering you probably already have what you need if your insert plates take guide bushings and already have them.

Dirk


----------



## Bonehead V.2 (Aug 23, 2009)

Nice tutorial. Thanks for posting it.


----------



## blademansw (Sep 14, 2009)

Excellent tutorial thanks!


----------



## Collett (Nov 4, 2010)

*Centering Router in Plate*

Actually ... it isn't important that the router be mounted exactly in the center of the plate because everything that you route is centered from where ever the bit is.

It's nice to get the router fairly close to the center so that router bits that are close to the size of the opening will not start carving a new path for themselves on your router plate. I have made temporary plates out of clear plastic, plywood and hardboard and all work fine ... but the plastic ones with different size hole inserts are the nicest to work with.


----------



## Deanp (Dec 1, 2010)

Did you ever use a dovetail jig with an out of center dovetail bit?


----------



## bobj3 (Jan 17, 2006)

Hi Dean

That's big NO NO, the bit must be in the center,and in dead center a 1/28" is a big deal when it comes to dovetails...unless you like making fire wood.. 

It's like using a bent jig saw blade,like they say junk in junk out..

=======



Deanp said:


> Did you ever use a dovetail jig with an out of center dovetail bit?


----------



## Deanp (Dec 1, 2010)

Right on Bob I was just reading too much about how centering your plate was no big deal.


----------



## Slomoe (Feb 14, 2011)

falk said:


> Oh, FWIW, I'm just making the mounting plate out of malamine. Is that a dumb thing to do?


I sure hope you don't mean something like that cheap shelving material with the melamine on it. That is nothing but particle board which will go self destruct from Vibration, and moisture. The screws may get loose and break through. When that happens your router falls out the bottom and runs across the floor, or up your leg like a rocket. Think of the torque your router has when starting or cutting with a 2" bit.

Safety first!!!
Use aluminum or phonolic - glue Formica in the aluminum. If you don’t have the means to work metal – then buy a cheap one if needed –


----------



## Funwitwood (Sep 8, 2011)

Someone gave me a Sears Craftman router plate and it has about a 3 inch hole in it which seems a bit larger than some of the alignment inserts I have seen. I wanted the plate to get the router higher into the work and wanted a bigger opening for a panel bit. Are there larger alignment inserts available? What are the available sizes?


----------



## bobj3 (Jan 17, 2006)

Hi

Not that I know about but you can make your own very easy with some 1/4" plastic and a 1/4" bolt that you can chuck up in the router to get on dead center..by the way a 3" hole is a bit small now days it should be 4" for the big panel bits that are 3 1/2" to 3 5/8" now days..

Use a hole saw to cut the disk out of the plastic stock..

Amazon.com: HOLE SAW SET - 16 pc Hole Saw Kit- 3/4" - 5" inch - includes Case: Home Improvement

==



Funwitwood said:


> Someone gave me a Sears Craftman router plate and it has about a 3 inch hole in it which seems a bit larger than some of the alignment inserts I have seen. I wanted the plate to get the router higher into the work and wanted a bigger opening for a panel bit. Are there larger alignment inserts available? What are the available sizes?


----------



## jschaben (Jun 21, 2009)

Funwitwood said:


> Someone gave me a Sears Craftman router plate and it has about a 3 inch hole in it which seems a bit larger than some of the alignment inserts I have seen. I wanted the plate to get the router higher into the work and wanted a bigger opening for a panel bit. Are there larger alignment inserts available? What are the available sizes?


Hi Roger - I did a quick look at the SearsPartsDirect site and came up pretty much empty, not unexpectedly. :dirol:
Inserts are fairly easy to make. I started with an old Craftsman aluminum table shaper. While I never really did convince the thing to act like a router table, in the process I made 4 or 5 inserts with various size openings. 
Inserts can be made from most any material; plywood, acrylic, polycarbonate, mdf... etc. Simply cut some circles from the material to fit the opening and then put the desired size hole in the center. Just select the material thickness as close to the depth of the relief around the existing hole as possible. Small adjustments in height can be made by rabetting the edge of the insert or shimming the insert with tape or whatever. 
Hope this helps


----------



## Funwitwood (Sep 8, 2011)

Thanks everyone for your inputs.

The Sears router table adapter plate 925333 is made of steel and the opening is 3 inches.

I see now that I can make an insert to center up the plate hole with the router and mount the router to the plate. The panel bit will easily be high enough to clear the table. That will be the first step. If I need to I can widen the opening to 4 inches.


----------



## Mike (Nov 22, 2004)

Not centering your router in your mounting plate is like not aligning the tires on your car. It may work but performance goes way down since things are not adjusted properly. Centering your router only takes a couple of minutes and is essential if you want to use guide bushings.


----------



## del schisler (Feb 2, 2006)

*centering the mounting plate and bit to the plate*

this is what i did i put in a guide bushing in the plate up side down use a big opening guide and use a round bottom bit or a 45 degree bit and brought the bit to the guide bushing. That center the bit to the guide bushing which centered the plate . Tighten the plate to the router. Works for me or have i been lucky ???


----------



## grandpagrizzly (Sep 13, 2011)

I just found this forum and am anxious to see what all is available. Someone sent me a message but it is being blocked by my system.
GG


----------



## Aryan (Sep 19, 2011)

Hi...,Great post..It is really helpful to centered on mounting plate...a friend tell me about this site and i see is really good....Nice sharing.


----------



## fishuntbike (Jan 20, 2012)

I centered my router to the plate I just made out of 1/2 flexiglass. I located the center of my plate then drilled a small hole, layed my router with center bit on it and everything was measured from the center hole. I included the center insert came from Rocker by routing the depth of insert and drilled a 3" hole. The insert accommodate the PC bushing. Also I included 8 leveling set screws seating on magnets


----------



## rinthesun (Mar 27, 2012)

*Mounting Sears fixed router in a Rousseau Plat*

I have placed a step by step process for mounting my new Sears router.

workshopprojects.blogspot.com/2012/03/mounting-router-to-rousseau-3509-plate.html]Workshop Projects: Mounting Router to Rousseau 3509 Plate


----------



## bobj3 (Jan 17, 2006)

Workshop Projects: Mounting Router to Rousseau 3509 Plate

==


----------



## ggom20 (Feb 1, 2012)

Hello!

IMHO:

Centering is good for use of guide bushes.
with a very good lift or the fixed base system.

Now try centering a guide bush on a plunge router...

You'll find it is always false a bit later, the plunge collums got so much play
that it' s absolutely useless...

Seen the green Bosh POF 1400 with about +- 2/100 " that's +-o.5mm -hawfull.
My rioby's not better anyway.

The only way for accurate jobs with those plunge routers is the use of cutters with bearings.
That works for dovetailing to.

Regards


----------



## mpjredsox (Feb 18, 2012)

I have purchased an RT1000xl table from Canada, it is beautiful, it came with to laxan plates one with a two inch hole, and a blank. I also purchased an aluminum plate from them with a three inch whole that comes with a ring and a brass center piece. I have a Bosch 1617 router and I purchased a lift base. Your right when you say you agonize over the mounting of the router. I have no idea how to do it, I also purchased a fly cutter to cut a larger whole in the blanl lexan plate so I can use raised panel bits eventually. But there i don't know how to cut the whole with the small lip to holf the rings, or do I need to. I need Mounting and cutting holes for router mounting For the Real Dummies.


----------



## Neil Tsubota (Mar 20, 2010)

I like your link.

Finally found the page on the Rousseau 3509 plate.


----------



## BRAVOGOLFTANGO (Oct 11, 2012)

Great info, the Kreg Table I just returned had a clear guide overlay for centering, but I didn't particularly care for it for accuracy, albeit I measured and measured even with the single hole lineup, couldn't figure how that would be exact aside from measuring the template to insert edges while eyeballing the lineup hole.

This makes finding your insert holes precise when building a router table like I'm planning to start tomorrow.

Thanks for all the good info, us newbies need all the help we can get.


----------



## Willway (Aug 16, 2012)

Mike said:


> It is very important that your router be centered on your mounting plate. Many people sweat over this for hours remeasuring before they drill their mounting holes. The quick and easy way to do this is with a centering kit from Rousseau. These kits work with all brands of mounting plates that accept Porter Cable style guide bushings and they cost $5.
> 
> Step 1. You chuck up the centering pin in your routers 1/4" collet.
> Step 2. Insert the disk into the center hole of your mounting plate.
> ...


Thanks Mike. This may be the wrong place to ask a question but does this set work with the Grizzly plate you recommend?


----------



## Blakewnelson94 (Feb 21, 2014)

Thanks for the great post! all these stickies really help a newbie kick off


----------



## sunrunner (Apr 17, 2014)

In concerns to another reason why centering a router bit in a table is very important. I am an avid Incra LS Positioner User. If that router bit is not centered it is a bear to set up that accessory to work correctly if you can do it at all. I create tons of boxes with up to four different registrations and I'll tell you if that bit is not in the center of the router table you get all kinds of interesting results. But once both the router bit is centered to the table and the Incra Positioner is centered to the bit life is good.


----------



## idarwin (Sep 1, 2014)

Mike said:


> It is very important that your router be centered on your mounting plate.


Mike, could I ask you please to clarify (a) why it's so very important and (b) how critical the centering is? I presume it needs to be centered on the existing hole rather than the exact dead centre of the plate (if they differ; I don't know of any brands for which this is true).

Thanks!


----------



## jw2170 (Jan 24, 2008)

Hi Ian,

Mike is away for a short period.

However, the reason the router is centered on the mounting plate is so that the guide bushings are correctly centered.

If you never intend to use guide bushings, this is not critical as the cutter will reference of the fence.


----------



## idarwin (Sep 1, 2014)

Ah, makes sense, thanks!


----------



## sunrunner (Apr 17, 2014)

There are two reasons I can think of why it makes sense to center your router in the base plate. If you want to use an Incra jig and the bit isn't centered it is much harder to align the jig. In extreme cases I've seen the jig actually mounted crooked to compensate. If you use a pin router and the pin and the bit aren't aligned with each other the results you get are not acceptable. I found it is much easier if both pin and router bit are centered in their respective plates and the plates are centered to each other. 

Victor


----------



## bob156235 (Jun 14, 2009)

This reply may not be best-suited in this table mounted section, but the same topic is being addressed, so...

I never liked the base plate on my hand-held Ryobi R180 due to part of the round perimeter being flat and using it against curved guides/edges, etc. So I bought a universal round, clear, predrilled base which came with additioanl screws, a brass collar w/nut to hold the centering pin, and a brass (centering) pin shaped like a golf tee to theoretically "center" the plate around the router collet.

I cannot get the plate centered after numerous attempts! The predrilled holes are adequatedly sized, so there is ample room for the screws and heads to adjust to the router foot print. I installed the centering collar and it fits snuggly into the plate hole with no slop. I then snuggly pressed the pin into the collar while it "wedges" itself into the collar, presumably to center the plate, and while maintaining pressure, I tighten the router collet, then tighten the four screws, yet the plate is not centered! It is consistantly 1/32"+ off! 

This was a couple of months ago. I have used it since then, but now "rotate" the router so as to keep the same area of the plate against the guide edges when I'm not using a bearing bit. What can it be? Is the plate center-hole NOT centered? :blink:


----------



## DaninVan (Jan 1, 2012)

Hey, Bob; out of curiosity, are your screws conical on the underside (flat head screws) or flat on the underside (round or pan head screws). I keep seeing references and comments in books and articles suggesting replacing the existing OEM ones.
If either the countersink or the screw is conical then for sure it'll pull away from where you want it.


----------



## Cherryville Chuck (Sep 28, 2010)

Agree Dan. The best designs I've seen have flat countersunk holes that are enlarged enough to be able to move the plate a little to get to center.


----------



## bob156235 (Jun 14, 2009)

No, their not flathead. They're similar to a washerhead or panhead. The screw hole is oversize allowing the plate to center before the screw is tightened.


----------



## DaninVan (Jan 1, 2012)

That's very strange, Bob. 
You've obviously spent a lot of time and frustration over this, so please excuse my simplistic questions...I can't see what's actually happening.
A sideways force is being generated as the fasteners are cinched down?
Are all four (3 or 4?) screws actually centred in their baseplate holes, or are one or more maybe a little tight against a side(s) of the baseplate hole as the screw is run into the metal sub-baseplate? Can you rotate the baseplate to a different orientation, and still get exactly the same result? 
Have you tried _not_ tightening each screw down as you install it? Go around tightening down after you're sure it's actually aligned...check again after tightening each screw...trying to isolate which one's causing your problem.
Again I apologize if it seems like I'm not giving you credit for having tried those routines; just thinking out-loud what I'd be doing if it was in front of me.


----------



## bob156235 (Jun 14, 2009)

As the centerpin, shaped like a golf tee, is pressed into the brass collar installed in the center (bit) hole of the plate, the plate automatically "centers itself" as the router collet nut is tightened (like router bit). From there, it's simply a matter of tightening the screws going through the plate and into the screw holes in the router housing. The plate holes and router (housing) holes line up perfectly. [Note that even if they weren't perfectly lined up, the plate is already fixed in position and can't move at this point. It is only a matter of tightening the screws down which holds the plate to the housing. Afterwhich, the centering pin and plate collar are removed. Am my making this out to be clear as mud?


----------



## jw2170 (Jan 24, 2008)

DaninVan said:


> Hey, Bob; out of curiosity, are your screws conical on the underside (flat head screws) or flat on the underside (round or pan head screws). I keep seeing references and comments in books and articles suggesting replacing the existing OEM ones.
> If either the countersink or the screw is conical then for sure it'll pull away from where you want it.


+1...

Flat bottom screws into slightly oversized flat bottom holes.


----------



## DaninVan (Jan 1, 2012)

Perfectly clear, Bob. 
I am a bit confused however, mine is like a Xmas tree...maybe specifically for plunge routers? 
Bosch RA1151 Centering Pin and Cone
From their description, the brass collar is_ loose_ during the tightening process. Is it possible you've got yours tightened down, and it's actually applying sideways torque to the motor shaft/collet as you tighten the plate screws down...ie bouncing back once you remove the centring cone ?
I'm just spit-balling here; maybe someone with a lot more hands on can clarify this?


----------



## Stick486 (Jan 4, 2013)

Dan has the plan...
I go to plan something or another....

if the plate is "walking" when you tighten the screws you you need to tighten them like lug nuts on a car...
take up the slack...
snug a little bit...
move the next screw in a star pattern...
repeat often til you are tight...

now tight here by no means means cranked down because if you do you'll mis-shapen the screw sockets and then you're past the point of no return and a new plate is in order unless you can accurately re-flatten the socket bottoms...


----------



## bob156235 (Jun 14, 2009)

That's the set-up, Stick. 
The method you desdcribed to screw on the plate on the router is exactly what I did.
There is no reason to the off-set other than the plate itself milled incorrectly.
Anyway, was wondering if anyone else have ever experienced this. 
Thx for the input.


----------



## Stick486 (Jan 4, 2013)

bob156235 said:


> Anyway, was wondering if anyone else have ever experienced this.
> Thx for the input.


only w/ PC and sears routers....


----------



## DaninVan (Jan 1, 2012)

Bob said...
"As the centerpin, shaped like a golf tee, is pressed into the brass collar installed in the center (bit) hole of the plate, the plate automatically "centers itself" as the router collet nut is tightened (like router bit)."

Sorry, Bob, but that's in conflict with the Bosch instructions that I posted. The collet nut needs to be tightened_ before_ anything else is tightened...especially the brass collar. The centering cone is the starting point for everything else being aligned (to it). The cone has to be rock solid as the starting point; not applying sideways pressure to anything.


----------



## bob156235 (Jun 14, 2009)

DaninVan said:


> Sorry, Bob, but that's in conflict with the Bosch instructions that I posted. The collet nut needs to be tightened_ before_ anything else is tightened...especially the brass collar. The centering cone is the starting point for everything else being aligned (to it). The cone has to be rock solid as the starting point; not applying sideways pressure to anything.


Hi Dan,
There is a mix-up here.
The brass collar is attached, and its nut tightened, to the new plate before placing it on the router. Only then can the centering pin be pushed threw it and into the router collet to tighten IT up. See pic in upper post.


----------



## DaninVan (Jan 1, 2012)

I did see it, Bob. Never the less, there's your problem...the centering pin has to be firmly held before you can tighten anything _else_ down.
It's the anchor for the alignment process, not the tool.
No harm in trying Bosch's technique? If that doesn't work than I'm out of ideas.


----------



## Slomoe (Feb 14, 2011)

Do you have the router motor locked in before you set the alignment? You could be shifting the motor in the housing after you have set the alignment pin on center, therefore creating a shift in the pin or bit. Clear all saw dust from the housing and motor before assembly. Set the motor near the depth you expect to cut in case there is any misalignment between the housing base and the motor. Then lock down the motor in the housing to remove any side clearance. Then mount the base plate loose but snug. Install the guide bushing loose but snug. Insert pin in collect and tighten. Rotate the router shaft by hand to center the plate and bushing. Check for concentricity, and then lock down the bushing. Next, lock down the plate nice and even as you go around it to center it. Re-check alignment, and check concentricity. Now loosen the router motor, raise it 1/32, retighten motor and recheck concentricity. Take note of the pin when you rotate the shaft in the loose and motor tight position for any change in concentricity. Next time around you should be able to just drop in the guide bushing and pin (locked in) and tighten the bushing and you are good to go.
Be sure the motor shaft is straight and the bearings good, with no side clearance.


----------



## GregLittleWoodworks (Dec 9, 2014)

Most of my routers came with a centering pin and I did not use them at first. I then realized that the router plate is not always accurate as you would expect it be with the factory settings. I have since centered all of my routers.


----------



## knuxiey001 (Jan 15, 2015)

that's a cool center routing table.


----------



## chris kenney (Mar 15, 2015)

Quick question on this topic I just noticed. The plate which covers my router arbor and bit is not screwed down. The router is mounter under the router table on the Grizz 1023. I am a new woodworker. Is this inherently dangerous? Should I just abandon the table saw top and get a good router table? Thx.


Chris Kenney
Acworth, GA


----------



## BrianS (Nov 7, 2004)

Chris, maybe some pics if you can?


----------



## DaninVan (Jan 1, 2012)

Are you talking about the accessory insert plate? The one that replaces your standard from-the-factory base plate?
If that's the one you mean, the drop in insert plate that recesses flush with your table top, the answer most often given is that if it's a good fit to the recess than the weight of the router hanging off it should be enough to keep it firmly in place.
Bill Hylton has a ton of info on baseplates etc., in his book Router Magic...look for the newest edition on Amazon.com .


----------



## nsecrist (Jan 13, 2015)

*Good Tips Mike*

Mike,

These are great tips - thanks for sharing.

Nate


----------



## chris kenney (Mar 15, 2015)

Yes--there are 2 metal insert plates which fit over router bit opening on Grizz 1023 with router table extension . They both have a small metal nib which fits into a very small machined opening inside the rim of the opening. I am not sure I like this set up for versatility and accuracy. Considering getting a Kreg or other brand router table.


Chris


----------



## PhilBa (Sep 25, 2014)

I have a 1023 with the same router wing. It's usable as a basic router table but without doing some drilling it's pretty oldschool - all your adjustments require fiddling under the table. Some people have mounted "above the table" plungers and drilled a hole for the adjustment screw. The two insert plates are fine, they won't come flying out or anything. 

I wanted to have a separate table with a lift for an Incra LS positioner so I built my own table. Lots of reasons why that is a better way for me - LS positioner, solid lift, better DC, more storage for routers, router bits and such. If I was only doing a little table based routing, I'd probably stick with the 1023's wing.


----------



## niswanger (Jan 7, 2016)

Hey gang, read about this on a few other posts but figure it's more appropriate to ask in this post. I have a Bench Dog Pro Steel top, Bench Dog Pro Plate I Large (specifically designed with pre-drilled mounting holes for my router, and a Milwaukee 5625 (fits the Pro Plate). Do I still need to do a centering operation? I figure I might get a 1/1000th of an inch adjustment but that's probably about all.

Thanks,
Roy


----------

