# How do you prevent pieces moving when using pocket holes?



## InstantSiv

Hi, I cannot figure why I am still getting movement when clamping pieces and using pocket holes(see pic for orientation of pieces, sorry for quality… drawn on tablet). I need the two pieces to be perfectly flush with one another because I am flush trimming and using those as the bearing surface. Kreg makes a specific clamp for that orientation but the reviews say that it's prone to breaking. I made a quick clamping jig(pictured) to clamp the pieces but the pieces move and are not flush.

What are your thoughts?


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## levan

lOOKS LIKE THAT SHOULD WORK. Must be slipping on part b. Maybe you could put a clamp from the end of part B to the corner jig, If you have a deep ingagement clamp long enough. You might also try putting stick on sand paper on you corner jig to help with slipping.


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## a1Jim

Maybe I'm saying the same thing as Lynn
clamp part "B"to the bench then put a board as a stop on the end your going to screw together also on part "B" 
put a clamp on the stop block and the other end of part "B". The stop block will prevent Part"A" from slipping outward.


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## Nicky

I just did a fair amount of experimenting with pocket holes. If you screw down to tight, the joint will be uneven. Also after drilling the pocket holes, try a pilot hole with the pieces clamped (1/8" worked for me)

I've gotten close but not perfect.


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## Loren

Glue them first.


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## MT_Stringer

Clamp the heck out of them. You are about four clamps too short. 
I clamp the workpieces to the table.


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## Redoak49

I do not have that kind of problem but you need to clamp things tightly and not let them move. The idea for sandpaper glued into the jig is a good one.


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## Whiskers

One thing that helps with pocket holes to prevent movement is don't run them all the way down tight at first. Get screws in both holes most of the way than finish them off. You might also want to add a sliver of 1×2 along the inside edge on top of part B and up against A so that A is engulfed on both sides.


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## pintodeluxe

Use the kreg brand clamp, and set it fairly tight. It works much better than a standard F style clamp. Also, you can pre-drill the pocket scew with a pilot bit, but it is usually not required.


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## MT_Stringer

@OP - I was looking at your drawing again. If it was me, I would rotate your workpieces 90 deg to the left. That way, the piece with the pocket holes is on the table.

Use whatever means you can cobble up to capture the vertical piece so it can't move backwards , left or right.
Clamp the piece with the pockets to the table and run the screws in. I have done this before. It should pull up tight.

Good luck.

Note: It is not beyond me to drill holes in the table, or make up temporary clamping jigs so I can secure the workpieces. I do whatever it takes. Sometimes those videos you may see on UTube, aren't as simple as it seams.

Good luck.


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## cabmaker

I used to do it with a ritter table and pneumatic plungers. Check em out!


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## craftsman on the lake

Clamping it correctly should work but I often assemble things with a pin nailer. The nails are about the size of a thin sewing needle with no head. You can't see the place it was nailed unless you get really close and really hunt for it. And they hold amazingly well. Glue / pin nail / then screw.


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## InstantSiv

Thank you everyone for the responses.

I kinda dismissed part b moving because I didn't see any movement while screwing. I'll have to rethink that and secure part b. I'm going to try the sand paper first and if that doesn't work then try to clamp part b to prevent movement.

I've also heard of sprinkling sand, rubbing sand paper together, over the glue to prevent two pieces from shifting around while gluing. Anyone heard of this? I think it was to prevent minor shift while clamping so I don't know how well it would work with pocket joints.

Thanks again. I'll report back with my findings.


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## InstantSiv

Okay just got done experimenting a little.

Sand paper on the jig still caused movement. I was a bit disappointed this didn't work because it was a super simple and elegant way to solve the issue. I then tried what MTStringer suggested(putting part A flat on the table) and the experimental jig I threw together worked!

Part C & D was just scrap wood I clamped together(not shown in pic). C/D was clamped to the table top with a single clamp. Part B is pushed into part C/D by Part A. Part A is clamped to the table. Part B was simply held down by my free hand because I don't have clamps longer than the piece. Perfectly flush tight joint.

I'm still going to have to design a better jig than this but I think it's a working concept. Thank you MTStringer for the suggestion and others who have chimed in. This has been racking my brain for a while now.


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## a1Jim

After all is said and done I agree with Loren just glue it first ,let dry then ad pocket screws.


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## bowedcurly

use a mig welder, just kiddin, pilot holes work well, and bigger clamps


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## rg33

I wonder if it would help to halfway screw both screws first then come back and finish them both as opposed to fully screwing one in before starting the other….it would give you another semi-anchor in addition to your clamps


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