On Milling


Though I know better, I ended up with this seriously warped side panel for the steps I’m making for my son.

It's got a wee bit of cupping.
Convention holds – and I agree – that there are two (2) good methods for milling.

The best method is to perform you initial milling and get pieces close – but not all the way – to size. Then give them a few days to sit and re-acclimate. They will cup and twist some as the newly exposed surfaces acclimate. You can then remove the cupping and twisting when you do your final milling to exact size just before assembly.

The not quite as good but still usually acceptable method is to start milling and take the piece right to exact final dimensions. Then assembly immediately, before anything can warp or twist.

Alas, I did not heed either of these strategies. I was simply working as much and as fast as I could during the limited time I had. This meant that on Saturday I milled pieces from start to their final, exact dimensions. Because of the 2x10 stock I was using, this involved taking ½” off the face of the boards. Then I put them away for the night.

On Saturday night I found them to still be very (if not perfectly) flat. I cut pins in the top of my side pieces and then glued them up.

On Monday night I entered the shop to find one of my steps severely cupped. Then I unclamped the sides and found that one of them was severely cupped also.

At least the table saw is flat. The top step? Not so much.
I’m hoping that I can fight them to flat with my Woodpeckers aluminum cauls and then force the step stool together without too much trouble. If that doesn’t work I’ll try cutting a slot or two in the inside face, clamping it flat and filling the slots with epoxy. As a final resort I can cut the two (2) pieces apart, re-flatten and re-glue.

Whichever method works, I’ve given myself more work and probably compromised the level of quality for the finished piece. Next time I’ll try to slow myself down and save time by milling properly.

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