# Router bit depth for Porter Cable 4212 Through Tail setup



## gary7101 (Jan 9, 2019)

I recently purchased a PC 4212 Dovetail Jig - I'm new to dovetail making - for a couple of chest projects. 
In following the instructions, setting the bit depth for through tails w/ 17/32 wide bit that came with the jig. I'm using the thickness of the matching pin board - 53/64" (just shy of 7/8) and find that the bit cannot cut that deep without creating a groove at the top of the cut.

I'm using the specified bits for the tails and pins as directed, along with the correct guides in the base of the router (PC router as well).
I have not been able to create a pin to match as they are too wide to fit the tails as cut, as the tail depth seems incorrect. A tail that matches depth leaves a shank-groove and a lip at the top of the pin.

I'm not sure how to resolve this issue if the bit cannot cut the correct depth. Seems I must be missing something in the setup to have such a mismatch in tail and pin widths.

Any suggestions would be EXTREMELY WELCOME!!


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## therealSteveN (Oct 29, 2016)

Most people when first encountering anyone's DT jig will say, What?


> ?


???? maybe a few other choice words. Beyond that IF "I recently purchased a PC 4212 Dovetail Jig" means you bought one new, and unopened, then everything you need to make through, 1/2 blind DT's and finger joints/box joints is in the box. The ton of patience you will need isn't in there. Go slow, keep rechecking with every change.

Just in case you don't have them, look over both manuals carefully, and just go one step at a time.

Instruction manual

Supplementary Instruction

If it was a secondary sale, and the jig was used, just make sure your bits, and both of the template guides are to PC spec. The jig allows for using non standard bits, but for starters just stay in the slow lane.

Otherwise reread everything one more time, and double down on "ROUTER BIT DEPTH" on page 12. Beyond that make sure you have the correct bit collar on.

Good luck,


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## gary7101 (Jan 9, 2019)

Thank you for your reply.

No, I bought it new, and have been goofing around with practicing the various joints, and for the most part have had limited success with some, but not all. Not to mention sacrificing a few scrap pieces of wood!

I'm following instructions for the through tails. However, the material I'm using and the bit/guide combo that came don't seem compatible as I can't get the tail depth for a through tail to match the thickness of the boards - just shy of 7/8". Pins turn out OK but won't seat in the tails because of height issue.
Otherwise, if I go the full depth in the tails, I end up having to spend a bunch of time paring and they end up looking kinda sketchy and not a good tight joint.

When I make them on the jig at board thickness, I get a ridge at the top along with a groove caused by the bit shank.

I'm looking for help with that issue specifically. It's starting appear that the bit won't work for the dimension of wood, and unless there's another bit/guide combo for the through joint jig that can handle the board thickness, I'm thinking I'll have to hand-cut everything - which I can do.

Thanks in advance!!


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## mpsprunger (Apr 22, 2013)

youtube has a helpful video


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## gary7101 (Jan 9, 2019)

> youtube has a helpful video
> 
> - mpsprunger


Thanks - YouTube has literally thousands of helpful videos, anything specific you were thinking of with a link?


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## Rick714 (Oct 2, 2020)

I know it is kind of late to respond, but your problem is caused because the 4212 jig set as supplied will only do dovetails in material up to 3/4" thick, per the instruction manual. You are trying to use 7/8" stock. The supplied dove tail, bit only has a cutting edge 3/4" long with a angle of 7 degrees, not long enough.

Do not know if it will work, but Rockler lists a bit #91111 that is 7 deg and 7/8" long, which may work. The straight bit supplied with your jig has a 1" deep cutting edge, so it should work. Probably worth a try


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