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I'm working with pocket holes on half inch baltic birch plywood. The particular jig I'm using is the Kreg jig (the one with 2 holes) and I've only used it a couple times before so I know the bit is sharp.

I'm finding that no matter what I try, the quality of the cuts is pretty bad and the store bought plugs (of the same brand) are loose. I know that I can use wood filler to solve the latter but the cut quality cannot be fixed by any means I know (which is why I'm asking this question).

Here's a sample I made. I glued the plugs and after the glue dried, cut them with a flush cut saw. I then lightly sanded with 100 and 220 grit. The edges look awful!

enter image description here

Anything I can do to solve this?

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    Off-the-wall solution is to not use pocket screws :-) It's actually not a bad idea to only use pocket screws where they can't be seen, then this sort of thing isn't really a problem. – Graphus May 3 '17 at 12:12
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    I think if you're going to have the screws on a visible surface, might as well just own it and show the screws (they do make pretty screws). Those plugs are, imo, like putting perfume on a pig. – jbord39 May 3 '17 at 17:09
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You have two things happening here. First is loose pocket hole plugs. Second is tear-out of the veneer face of the plywood.

For the problem of loose pocket hole plugs, you will want to make sure you are drilling straight and not moving side to side as you drill, accidentally widening the hole. For the most part, the jig prevents this, so I'm not really sure that's your problem. In fact, I'm not really sure you have a problem: your work looks similar to lots of other examples of pocket holes I've seen. For example, here's an image from Lee Valley, showing examples of the plugs they sell:

Pocket hole plugs, courtesy leevalley.com

Image credit: leevalley.com

Their fit is very similar to yours. If the plugs simply do not fit to your satisfaction, you might want to try making your own pocket hole plugs instead of using the store bought ones. There are various instructions on how to do this around the Internet. Here is an example that uses a specialized table saw sled, and here is a simpler one that uses the pocket hole itself as a jig.

For the problem of veneer tear-out, you'll need to adapt one of the usual techniques for dealing with tear-out to work with pocket holes. The techniques I am aware of are:

  1. Using blue painter's tape to reinforce the veneer.
  2. Using a sacrificial backer board to support the fibers being cut.
  3. Scoring the veneer along the area to be cut.

Option #1, reinforcing with blue painter's tape, would be the easiest thing to try, so I'd probably try it first. This technique works very well to almost completely eliminate tear-out when cutting veneered plywood on a table saw. I imagine it would work pretty well with the pocket holes, too. The only downside is getting sticky painter's tape residue all over the saw blade/drill bit.

Option #2 is to support the fibers with a sacrificial board. Clamp a sacrificial board to the face, so any pressure on the fibers to move up and off the face of the board is counteracted. The sacrificial piece will need to be a known thickness, say, 1/4" thick, so you can adjust your pocket hole jig accordingly. I.e., instead of adjusting the jig to drill into 1/2" stock, adjust it for 3/4" stock. A caveat here: normally the tear-out you're trying to prevent is where the blade/bit is exiting the stock, i.e., on the back, so normally this is a backer board. You're trying to prevent tear-out on the front. But it might be worth trying anyway. I think the drill bit is probably lifting some of the veneer's fibers up and off the board as it cuts, and supporting those fibers would help make the cut cleaner.

Option #3 is to score the veneer where it's going to be cut. I'm thinking this would be the trickiest of my three options. To do it, hold a plug against the location that will eventually be cut away, and trace it with a sharp knife to score the veneer. It would take some experimentation to figure out where the plug should be held, as this isn't something that is entirely clear from the jig setup. But if you can manage to score the odd shape in the correct location, I think this option would work well.

For any of these, I'd want to experiment with my technique on representative scrap before using it in my project. But honestly, that advice is applicable any time you're trying a new technique.

  • 2
    Sometimes wobble happens when you don't have the jig clamped down well enough. – CharlieHorse May 3 '17 at 13:43
  • The sacrificial board should work, as the tear-out is only happening on one side of the "cut". The bottom side of the hole in the picture looks good, whereas the top side doesn't. This is the spinning of the drill bit. – mmathis May 3 '17 at 17:12

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