On 1/14/2015 3:30 PM, Leon wrote:
http://ezine.woodworking.com/JigBase...Jig/index.html

Notice on the video how long it takes to drill the holes when drilling
at this angle and also notice how the pieces don't stay aligned. There
was an obvious twist on the corner joint.

I have the Kreg Jr. jig; the one that is basically the drill guide
alone. You need to clamp it to the work with a separate clamp. I have
used the Kreg face clamp and the Kreg AutoMax clamps for both the
drilling and for holding the pieces while driving the screws. I also
jury-rigged a jig on my bench vise when I had many face frame pieces to
drill:

https://www.flickr.com/photos/gdguar...ream/lightbox/

(The small 1x2 block shows where the actual 1x2 work pieces would go)

I have found that in both operations - drilling and driving the screws -
tight clamping is essential. When drilling, the rotation of the bit will
cause the work piece to move laterally if it is not firmly held in
place. This problem is made more likely if you don't have the drill up
to speed before it touches the wood.

You have to be even more careful when driving the screws. The screw's
motion creates a *strong* tendency to twist or shift the pieces out of
alignment. I got a couple of the Rockler "Pock-It" clamps at a deep
discount, which looked like they would hold the pieces together and keep
them flush at the same time.

https://www.flickr.com/photos/gdguar...1013/lightbox/

I have not found them to be adequate. Holding the piece "off center" as
these clamps do does not give adequate protection against twisting. I do
still use them, but add a face clamp as well:

https://www.flickr.com/photos/gdguar...ream/lightbox/

And I make the face clamps *tight*. I can't overemphasize this. The
pieces will shift given the smallest freedom to do so.

Sometimes I take the "suspenders and a belt ...and more suspenders"
approach:

https://www.flickr.com/photos/gdguar...4446/lightbox/

I've now used pocket screws on a number of projects, several times for
face frames as in the video. I can say that I'm not surprised that the
clamping shown in the video was (evidently) inadequate.

I usually preface any "advice" like this by mentioning my relative lack
of experience; I don't want to pretend to have expertise. But I don't
think I'm using the system incorrectly; it seems to be simply the nature
of the beast.


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