Wood Frame Does Not Lay Flat

[Jeff Welsh]

Hi,

I'm trying to build a simple 2' by 4' frame out of 1x2 stock. I'm joining the 1" sides together with butt-joints, using pocket-hole screws.

I've used my Kreg Pocket Hole Jig to drill the holes (two in each board) and I'm using a Kreg Right-Angle Clamp (first time I've used one) to hold the pieces together while I"m putting the screws in.

I'm laying the pieces flat on my workbench to assemble them, but once I screw it together, the frame wobbles a little because it no longer lays flat. When it's on my workbench, the "high-end" probably sets a 1/4" off the workbench.

Any idea what's going on and how I can prevent this?

Thanks for your help!

[KregRep]

Please contact our team at 800-447-8638 or kregtool.com/help - They will be happy to assist you with this. Thanks!

[Tony Peters]

If your wood is not perfectly flat, it will do this.  The clamp only secures a small part of the whole wood piece and the rest could be twisted somewhat.  You could try wetting the wood with a sponge and clamping the finished piece down to a flat table on all 4 corners and leave for a few days.  

[Stuart Kennedy]

Is your timber square and is your end cut square? It's also better to clamp your timber flat to the bench if you can while screwing together.

[Jeff Welsh]

My end cuts are square (miter cut and verified with a carpenter's square). The wood is the best I could find - no twists or crooks, but there is a little bowing along the length. I've built the frame with the bows up a little - it will be pulled flat when I screw it down.

I think the big issue was not clamping the wood to my bench. I also saw another post that says the wood can travel a little when the screws are inserted if the pocket holes are not completely drilled through. I made sure to extend the screws slightly through the wood (then backed them up a little) before I assembled my pieces. The last two frames I made this way are much better.

Thanks for the help!

[Stuart Kennedy]

Glad you have a resolution Jeff and working with Kreg screws is a learning curve. I've been working with oak and I didn't feel as though the fine screws were getting a secure enough grip so I only used one as a pilot hole and then withdrew it and replaced with a course screw, which meant no splitting. However, I did snap the odd screw which creates a problem all of it's own. I also have'nt found the confidence in the system to assemble without glue. Maybe one day....

Jeff Welsh said:

My end cuts are square (miter cut and verified with a carpenter's square). The wood is the best I could find - no twists or crooks, but there is a little bowing along the length. I've built the frame with the bows up a little - it will be pulled flat when I screw it down.

I think the big issue was not clamping the wood to my bench. I also saw another post that says the wood can travel a little when the screws are inserted if the pocket holes are not completely drilled through. I made sure to extend the screws slightly through the wood (then backed them up a little) before I assembled my pieces. The last two frames I made this way are much better.

Thanks for the help!