Cutting U-Shape with a band saw - what's the right way?

[rudy de haas]

When I needed to cut a bunch of square bottomed U-Shapes (1 5/8 wide; 1 1/2 deep) into 2 x 4s yesterday I found that I:

1 - cut the two "vertical" edges of the U

2 - cut from one outside corner down to the bottom of the U on the opposite side. This cuts out a triangular shaped piece.

3 - cut from as near to the bottom of the triangle as i could to as close to the opposite bottom corner as I could get

4 - leveled off the bottom in either two or three passes depending on how close I got in steps 2 and 3.

At best, this generally let me make the U in five cuts when I got it right. Often, however, it took more and the smaller cuts tended to produce small pieces that fell down between the blade and inside edge of the table insert - which meant I had to stop the saw, clear it, and restart.

I got the job done, but there has to be a better way. Cam someone please tell me what that is?

[Luke Bergin]

If I had a bunch to do, I would put on a small blade that could handle the curve better, or drill out the bottom of the "U" with a forstner bit or spade bit depending on how nice it needed to be then just make the straight cuts. Of course I would have to buy a bit that big because I don't have one, but it might be worth it if I had a bunch to do.

If I just had a few to do, I'd just make it work with the blade I had on the saw like you did.

[Matt Day]

Depends how many you need and th finish quality, but consider making a jig for the router table.

I think if it was me, I'd set up a stop block to cut the straight parts first (one side, flip, other side). Knock those out than hand cut the radius to connect the straight lines.

Edit- using a forstner bit is a great idea too.

[Greg McClurg]

You could turn the 2x4 on edge and use a dado blade on the TS

[glenn bradley]

You could turn the 2x4 on edge and use a dado blade on the TS

I'm with Greg, use a dado stack.

[rudy de haas]

You could turn the 2x4 on edge and use a dado blade on the TS

I didn't because:

1 - I don't have a dado stack (one is on my wish list)

2 - I was actually making these in the ends of the 2 x 4, not along their lengths.

[Mike Circo]

I vote for the Forstener bit option. Especially if you have several to do. (or a bunch as you say)
Not cheap, but Harbor Freight has an entire set of bits that includes a 1 5/8 size. $38 for 16 bits, but you'd have a SET. probably not the best quality, but sure to bore into pine without too much trouble. Single bits are probably available somewhere.

[richard b miller]

i too agree with the brill bit option.
if you don't have a forstener bit, you could use a large drill bit. i've don't that numerous times in the past. i used a 1/2" bit and jig saw (i was cutting out windows in plywood sheets)

[rudy de haas]

If I had a bunch to do, I would put on a small blade that could handle the curve better, or drill out the bottom of the "U" with a forstner bit or spade bit depending on how nice it needed to be then just make the straight cuts. Of course I would have to buy a bit that big because I don't have one, but it might be worth it if I had a bunch to do.



I tried the forstner bit idea last night - easy to fix the corners with the bandsaw and overall both simple and efficient. Thanks for a good idea!