Purpleheart and Pocket screws

[John Sanford]

Yesterday, I assembled a purpleheart face frame with pocket screws, and encountered some "difficulties". Fortunately, I did some tests beforehand with offcuts, otherwise I would have been a very, very unhappy camper.

Even though I was using Kreg fine thread pocket screws, the secondary piece (i.e., the one without the pocket in it) was splitting.

In order to eliminate this problem, I ended up following this regimen:
Drill the pocket screw in Piece A
Set both A & B down on workbench, clamp into position.
Run pocket screw partially, through A and about 1/4" into B.
Back pocket screw out, unclamp B.
Using a 3/32" bit, drill a pilot into B, using the partial hole left by the screw to guide the angle.
Add light glue, (narrow face frame so only 1 pocket screw per joint), reclamp, drive pocket screw.


While the results are satisfactory, the process was much, much more involved than it should have been. The time savings I was going for by using pocket screws disappeared.

My questions for y'all are two:

How can I speed up the use of pocket screws with very hard woods?

Does anybody make "pocket pilot" bits that won't increase the depth of the pocket? Such a bit would have allowed me to drill the initial pocket, clamp up the joint, and then use the "pocket pilot" to drill a pilot hole in Piece B.

[Jim Becker]

Purple heart is brittle....you need to pre-drill (as you have done) and use the fine thread screws. (I split off a piece of the purple heart "B" on the front of my tack trunk project the other night...with a 23 gage pin nail)

[Stan Urbas]

If it's any consolation (and I know it isn't), I have the same problem with VG fir, and it is quite soft.

[David DeCristoforo]

http://www.amanatool.com/boring/55270.html

[Mike Heidrick]

Did you try some different pocket screws? CSH or McFeelys Type 17 tip maybe? I would think the Kreg would predrill as well - just trying to give some other options.

[Mike Heidrick]

http://www.amanatool.com/boring/55270.html

Would those work with a Kreg Foreman?

[David DeCristoforo]

"Would those work with a Kreg Foreman?"

Don't know. Most machines like that require a specific bit length and many have a unique chuck. But for any jig that uses a hand held drill or that will acept "standard" drill bits, they work fine. There's lots of other mfgrs and sizes available. Search for "carbide tipped face frame counterbore" or "face frame counterbore" or "carbide tipped counterbore".

[Jim Becker]

http://www.amanatool.com/boring/55270.html

Now that's a nice idea....a step bit that has an adjustable center bore length. Very nice for this particular problem since it's very hard to get perfect alignment after the fact with a second bit.

[Marcus Ward]

I don't know about you guys, but when I hear "pocket screws" and "purpleheart" in the same sentence, it makes me think of that grand store down here in the Ozarks, "Frank's Fine Wines and Bait Shop". :D :D

[guy knight]

had the same problem while doing face frames in jatoba gave me a good reason to buy a domino:)

[Chip Lindley]

There are carbide pocket hole bits with a separate center drill. But, these may or may not work in your particular jig. The center bit may or may not be made to drill deeper than usual for a pilot hole in *piece B*
http://woodworker.com/cgi-bin/FULLPRES.exe?PARTNUM=133-744&search=Pocket%20Hole%20Drill