Best Way To make a Rabbet?

[BigguyZ]

OK, so I'm making a table saw workcenter, and the design calls for rabbets. The article recomends using a dado stack in the TS to cut the 3/4" x 3/8" rabbet into 3/4" MDF.

I have a dado stack, but I have yet to buy or make a dado throat plate. So, I was thinking that I could either use a dado stack without any throat plate, or use a rabbet bit in my router. I have a brand new rabbet bit that uses interchangable bearings to adjust the size of the rabbet. If there's a bearing that allows me to cut a 3/4" rabbet, should I use that instead?

[LarryG]

I have a brand new rabbet bit that uses interchangable bearings to adjust the size of the rabbet. If there's a bearing that allows me to cut a 3/4" rabbet, should I use that instead?

Yes, but make at least two passes (i.e., cut 3/16" of depth each pass) to ease the workload on the bit.

Assuming reasonably large panels, since it's MDF and a non-through cut, you could do this on a TS without a throat plate. The router will be safer, though.

[jziegler]

I don't think it's very safe to use the table saw without a throat plate (and the BT dado plate is questional). If you have a bearing, use the rabbet bit. I don't know that there will be one small enough though.

A trick that I've done a few times is to set the dado stack narrower (say 3/8") and then you can use the dado blade with the stock throat plate. Make 2 or 3 passes.

Jim

[Otter]

Another option is to use a 1/2" straight bit in the router and a fence. You can set the bit to the full 3/8" hight and then making several pass moving the fence a 1/8" back would do the trick.

[BigguyZ]

Well, I don't have a router table set up yet, so if I did go with the router rout (no pun intended), then it'd be handheld.

The panels are a decent size- 11x18" I think is the smallest I'b be using.

[LCHIEN]

Another option is to use a 1/2" straight bit in the router and a fence. You can set the bit to the full 3/8" hight and then making several pass moving the fence a 1/8" back would do the trick.

Using a narrower bit, you stll have to limit the depth of cut because the bit is weaker.
Overall, I find making a dado cut better for long passes. Bite the bullet, make the dado plate, you'll need one anyway. It's an investment of 20 minute for the future of your woodworking. Once you have a dado plate you will always have the choice of dado or router. Until then, you are limited.

[ChrisD]

BigGuy,

Like Loring said, whether you decide to use the router or the TS now, having a bunch of throat plates for different uses definitely helps.

In case you're not sure how to make one that will fit the opening on the BT3100 perfectly, search for the member vinht. Vinh has a drawing with exact measurements for the rabbet and screw locations.

Now this may sound like a chicken-and-egg situation because now you need to cut rabbets for the throat plate, which you need to help you cut rabbets in the first place! The rabbets on the throat plate are not that deep or wide, so nibbling away with a regular blade should work.

[BigguyZ]

Thanks Chris, but I'm a darksider with an old Craftsman TS.

I don't know how long it takes to make a decent-enough TP, so I was looking for other options. But I guess I should just bite the bullet and make my first...

[radhak]

I don't know how long it takes to make a decent-enough TP, so I was looking for other options. But I guess I should just bite the bullet and make my first...

take it from me : it is simpler than you think. just a couple of hours, not even a whole evening.

i made a zero-clearance TP when i was a abject newbie : having used a TS for just a month or so, and while i had a lot trepidation before, once i was done it was more like : is that all it takes?

i used mdf, and used a jigsaw to cut the general shape and a router/table for cleanup and for the various rabbets etc. i messed up one within the first 20 minutes and wasted another 20 minutes trying to rescue it; gave up when i realized i was trying to save just a 4" x 10" piece of mdf and nothing more.

And yes, the effort on the 2nd piece was even less ('experience' !). once the piece is cut to the fit into the opening, raising the blade slowly was smooth - nice thing about mdf. Check out this step-by-step at Woodsmith.

[BigguyZ]

I think their server is having issues. Both Woodsmith and Shopnotes aren't working....

[RodKirby]

I have been routing rabbets in MDF for years!

I have a 1" dia spiral bit "permanently" mounted in my larger Router table.

The method I use is to set the bit to the full height (say 3/8" for a 3/4" workpiece), and then make several (usually 3), passes, moving the router fence.

[linear]

Get one momma rabbet and one daddy rabbet...


(someone had to say it)

[Ken Massingale]

Get one momma rabbet and one daddy rabbet...


(someone had to say it)

Dangit Rob, you beat me to it!

[scorrpio]

I ordered a couple sheets of 1/4" thick UHMW and made 8 throat plate blanks from them. Got all 8 done in less than an hour total using same setups to machine all 8. One is now a ZCTP for regular blade, lenghtened to accomodate a riving knife. A couple are different size dadoes. Was real easy to make, too.

[BigguyZ]

Thanks everyone for the suggestions. I sucked it up and made myself a ZCTP for the dado. I used MDF and it took maybe 45 minutes. Had some issues, but I eventually realized what was going on and got it to work.