Drawing grooves in a leg with rectangle tool


I’ve drawn a 3/8x3/8 groove vertical on a 1 3/4x 1 3/4 leg. I want to make it 31/64 wide and 3/8 deep but I can’t center the 31x64 rectangle on the leg.

Thanks for any help.



How about uploading the model so we can see what you’ve got? Why 31/64" wide?



To fit 1/2" plywood.






Sketchup make 2017



I asked for your SketchUp file so we could see exactly what you’ve got and give you exact instructions.

Maybe all you need to do is use Push/Pull to push the side faces of the groove over 7/128"

It would be helpful if you’d complete your profile with that information and the graphics card, though.



It doesn’t…
you have to decide if you want to go this far in modeling, taper the 1/2’’ the last inch, so it fits? Upwards or downwards or both?
A suggestion with a textlabel (eg. ‘tight fit’) will suffice most of the time…



I’ll assume the leg is already a group or component. Without opening the group for edit, draw the rectangle the required size at any location across the face of the leg. Then move it by activating the move tool, putting the cursor over the midpoint of the 31/64 edge (you will get an inference snap), click there and move until you get another inference from the midpoint of the edge of the leg. Finally, edit->cut the rectangle, open the group for edit, and edit->paste in place.



1/2 in. plywood is slightly less than 1/2 in. thick. Assuming it is 31/64 thick (it’s actually probably closer to 15/32 in.) it’ll be a press fit but by the time the plywood is sanded a little, it’ll go in. In most shops making a groove that is exactly 31/64 in. wide will be the challenge.



Another triumph of “trade sizes” over common sense! They make it a bit oversize and then sand it to final thickness anyway. The only reason for the common weird sizes is deceptive cost control by reducing materials!

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Dave, I have the plywood glued in the 31/64 slot. It fits perfict. The router bit is made for 1/2" plywood.

Thanks, I have to run for lunch. Will be back in an hour.



Off course, I was talking about modeling, not the actual shop-work. Every sheet producent has it’s own peculiarities. We alway’s measure the total height of a pallet (~40 sheets) and divide…
Then, take a smaller router bit and pass two times…

Often, on location, the track saw set to a ~2 degrees angle:

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And if you use polyurethane glue, as seems common these days, it has gap-filling properties since it expands on curing (instead of contracting like PVA, say), so an absolutely tight fit may not be necessary.



True but a bit controversial. Polyurethane glue expands to fill gaps but the expanded foam isn’t strong. For strength it needs tight fitting joints much like other glues. The only true gap filler I know is epoxy.



Is this a relative thing? I’ve used it a lot since first coming across it a few years back and no joints I have made with it have come apart or come loose. That includes applying retrofitted strengthening blocks to a creaky staircase that is in daily use.

It may not technically be as strong as, say, Cascamite if you were needing to suspend high loads from a joint. But outside engineered timber structures, is that ever a requirement?

I’m not a carpenter or joiner so I am happy to be over-ruled on this!