Mortise and tenons

Mortise and Tenons – Low Cost Roubo 3

Last time out we had the legs and stretchers all marked for cutting the mortise and tenons. I want to apologise for not posting in a while – life gets in the way sometimes.

To cut the tenons I used a back saw. You could also use a panel saw, at this point accuracy isn’t too important so long as you cut them oversize (on the waste side of your marks). With joints this big, you’ll spend a while fine tuning them regardless. The hardest part is sawing these joints without a proper workbench and the workholding options it provides. I used the table top and some clamps to hold the legs down as I worked them.

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A brace and a bit to hog out most of the mortise waste

For the mortises I used a brace and bit to bore out the majority of the waste, followed by chopping out the remaining waste with a chisel. The proper way to do it is to use a bit thats the same diameter as your mortise. If you’ve never used a brace and bit and aren’t too confident I suggest using a smaller bit. You can tune it up with chisels later. Either way use a square to help keep it straight, and flip the workpiece over half way. You’ll be surprised at how easy a brace is to use, with a proper bit.

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Ready for a dry fit!

Once the tenons are all rough cut and the mortises are bored out, settle in with a chisel and mallet and start tuning the joints up. Using a straight guide block clamped to your work can be helpful to help keep your chisel square. A few hours later you’ll be ready for a dry fit.

You want your joints to go in with a little bit of pressure. A few mallet taps may be required but if it’s any tighter than that, pare off a little from your tenons. Check the base for square. Tolerances don’t need to be space age tight, but you want it to line up square so the leg vise works properly and the bench top sits flat. Again, don’t expect this to be quick. It takes a while.

Next time we’ll work on drawboring the joints and finishing up the base.

 

 

 

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