Mounting router

[eccentrictinkerer]

I'm a newbie with a newly acquired BT3100/Sears clone made from Craigslist parts.

I'd like to mount my PC router on the accessory plate, but there's an MDF board beneath the router opening. I'm assuming that this is standard mount.

Would there be a problem in mounting the router base directly to the aluminum plate? My brother is a machinist and would machine the mount accurately. Seems to me that the MDF board is superfluous (finally got a chance to use that word ).

All comments welcome.

J.D.
husbandforrentdotcom

[CManinLa]

J.D.,

I two am new to this forum & woodworking. However, I recently purchased the Craftsman 21829, which I assume is the same saw you are referring to.

Mine does not have an MDF board on the router portion of the table. I was able to attach my fixed base to the table. Of course, my router is a Craftsman & the holes did line-up to make the attaching very easy. My assumption is that since you have a PC router you may possibly have problems aligning the holes. That may have been the reason for the MDF addition.

If possible, you may want to include a photo or two to help with the diagnosis.

Good Luck & welcome.

cm

[Uncle Cracker]

Ryobi markets a router mounting kit for these saws, but the hole patterns are keyed primarily to Ryobi routers. If you have a machinist "in the family", then a custom adapter plate from 1/8" aluminum would fill the bill perfectly. Remember to make the center hole as large as possible to facilitate bit changes. You won't need the MDF.

[JR]

The Sears 21829 and older BT3x00/Sears clone have slightly different router setups for the accessory table.

The 21829 has mounting holes in the table for direct attachment of a router, as indicated by CManinLa.

The older models used a subplate. You'd attach the router to the subplate, then mount the sublplate to the accy table. It sounds like your piece of MDF is performing the subplate role.

I don't recall anyone mounting a router directly to the old accy table. There would be the benefit that the bit would be closer to the table; you could sometimes have trouble in the old config getting the bit to extend far enough. I might woner, though about the structural integrity of the table. It might be worth a trip to Sears to examine the new table to see if they beefed it up compared to the old one.

JR

[LCHIEN]

JR Is right, sounds like the MDF subplate was a former owner's addition.
Usually the pre-Sears 21829 had an aluminum subplate, rectangular with two dog ears cut off.

A piece of MDF might lower the router too far, unless a relief circle was milled in the bottom to allow the router to come up a bit, the alum plate was only 1/4" thick. MDF comes in all thicknesses from 1/4 to 3/4"

[gwyneth]

After a number of Craftsman, off-brand, and otherwise "non-standard base" routers (including Hitachi), I was really excited this weekend when my new Bosch arrived. At last, I thought, e-z mounting.

I have a 21829 and instead of direct mount, I used a piece of 3/8" plywood for the last router. I got out the aluminum plate purchased here from somebody's accessory kit and thought, yes, let's get that Bosch on there and try it out.

Several days later, the Bosch sub base and the aluminum plate are still sitting there, and every time I pass I get hypnotised into the old "rotate both pieces and maybe this time line up the holes". There seems to be one or two sort of possibilities.

This afternoon, I'm going to try the same thing with the 21829 table and Bosch sub-base.

But it's probably time to face up to reality and decide which would be less unpleasant: declutter the area around the drill press so I can use a hole saw to make another plywood mounting plate for the new Bosch; drill into that beautiful aluminum plate; or unscrew the old router's base from that piece of plywood and drill it (the plywood) to accomodate the Bosch base.

Always remember, that while a new tool will solve every single old problem you have in life, nature abhors a problem-vacuum, so it will rush to fill it with problems created by the new tool.

[kirkroy]

The bottom of the 21829 router 'table' can be seen in this thread:
http://www.bt3central.com/showthread.php?t=29466

[1index only]

wow, just what I was wondering but to afraid to ask. Looks like I'll be building a subplate too.

[steve-norrell]

FYI I had the Ryobi accessory kit with the aluminum router plate. It does not accept the Bosch router base and I had to drill and countersink holes for the screws plus another hole for the "through-the-table" height adjustment. It worked well until I was able to 'upgrade' to a JessEm lift.

I noticed that one of the newer Craftsman routers seems to be a clone for the Bosch so it may fit on the newer table saw accessory tables.

Good luck, regards, SN

[gwyneth]

FYI I had the Ryobi accessory kit with the aluminum router plate. It does not accept the Bosch router base and I had to drill and countersink holes for the screws plus another hole for the "through-the-table" height adjustment. It worked well until I was able to 'upgrade' to a JessEm lift.

Hey, Steve--were you able to line a hole up in the saw top with the hole for the "through-the-table" adjustment?

And maybe I'm not getting something. I can't understand why you'd need countersinks in the new base holes. For shorter bolts? It seems as if the nuts wouldn't be getting in the way of anything on that side of the plate, below the table.

Thanks.

[eezlock]

mounting router

You should take the clear or black base off the router and mount it directly to the alunimum base plate. If you mount it in this manner...it will give you the maximum height adjustment needed for most of your router bits when it is mounted in the router table. There will be times with certain bits that you will need them all the way up to get a good depth of cut on your stock. eezlock

[gwyneth]

You should take the clear or black base off the router and mount it directly to the alunimum base plate. If you mount it in this manner...it will give you the maximum height adjustment needed for most of your router bits when it is mounted in the router table. There will be times with certain bits that you will need them all the way up to get a good depth of cut on your stock. eezlock

If that was for me and not the OP, that's the first thing I did.

[steve-norrell]

Hey, Steve--were you able to line a hole up in the saw top with the hole for the "through-the-table" adjustment?

And maybe I'm not getting something. I can't understand why you'd need countersinks in the new base holes. For shorter bolts? It seems as if the nuts wouldn't be getting in the way of anything on that side of the plate, below the table.

Thanks.

Gwyneth:

Use the base plate (black plastic) as a template to locate the holes. Attach the router base body directly to the aluminum plate, without the plastic base plate (as you said you did).

Here are some pictures. "Router Plate 1" is the face of the aluminum plate that fits up against the underside of the accessory table. The router mounting screws are circled in blue and the height adjustment access is highlighted with arrows. A corresponding hole must be drilled in the accessory table. The other two pictures show the router base mounted to the aluminum plate.

The holes I drilled are slightly off but the countersinking allows for some misalignment. Also, the 'through-the-table" hole is about 1/3 again as large as needed so, even though it is off-center, I can still reach it. Not the neatest job -- but it works. Next time . . . . .

Regards, Steve

[LarryG]

A general comment, FWIW: one aspect of the plate-drilling job that seems to stress out many folks is getting the new holes in precisely the right locations, so the router base will be precisely centered on the mounting plate.

If that's you: relax, because such precision is not necessary. The large center hole is for bit clearance only: there's no critical operational relationship between it and the bit itself. As long as the bit is sticking up through the hole with adequate clearance all around, that's good enough.

Of course, you do want it to be as close to centered as you can get, but that's not difficult. Getting it to within a sixteenth of center, or even closer, is dead easy. But worrying it down to the last thousandth of an inch is pointless.

[LinuxRandal]

A general comment, FWIW: one aspect of the plate-drilling job that seems to stress out many folks is getting the new holes in precisely the right locations, so the router base will be precisely centered on the mounting plate.

If that's you: relax, because such precision is not necessary. The large center hole is for bit clearance only: there's no critical operational relationship between it and the bit itself. As long as the bit is sticking up through the hole with adequate clearance all around, that's good enough.

Of course, you do want it to be as close to centered as you can get, but that's not difficult. Getting it to within a sixteenth of center, or even closer, is dead easy. But worrying it down to the last thousandth of an inch is pointless.

I am not a machinist, but I have a friend who is one. I needed to transfer something from one bar to another, and keep the holes the same spacing. (more critical then this as it was much smaller). My friend told me to go to HF and ask for Transfer punches ($10). They would make alignment much simpler, and leave a dimple where the center of the drill bit should go.