Tube notcher/jig type thing

Now and again i need to notch some tubing at one or two angles and lengths.
I have a standard type notcher but it takes a while to set the tube up to notch it....this job usually needs around 100-150 notches at a time.

This is my attempt to make something to speed it all up.


Machining the bearing block in a small clarke lathe...there are two as i had ideas of notching the two ends of the tube at the same time..gave up on that though.




Turning the 20mm silver steel shaft and thread for holesaw



The bearing block with 20mm ID needle rollers. The recess in the end was originaly for a thrust bearing for the double notcher thing, where i was going to have the tube moving instead of the holesaw. It is the right size for an oil seal though so i'll put one in top and bottom.



The base of the tube clamp...the middle grooves in the back plate were going to be for a top sliding clamp similar to the bottom.




A bit of tig to stick them on. It's a bit undercut as my finger was touching the amp switch on the torch...when i finished i realised it was around 200 amps



Toggle clamp to hold tube.







Got it all fixed up to a back plate



The clamp bolt is a bit wonky ...i think it is down to all the pivot bolts being a bit sloppy as they are pivoting on the threaded bits. I will have to sort some tidier pivots.



The slot underneath the tube in the "V" bit is for some flat bar that will have some tube welded on to set the distance between the notches.



I still need to sort out the bar to get the distance between notches and also make a plate to mount it to a bench drill.

Nice, I like the over-centre Clamp. I need to make a new version of the one I made, once I'm in my new W/shop.



(I've the same lathe, Badged as a Warco, again to be replaced once I'm in the W/shop with a Bigger stronger Colchester or similar)

The notcher i bought only lasted a short while until the bushes wore out...i have fitted needle rollers to that as well to make it a bit better. It's the clamping and manually marking out the tube that gets a pain if there's a fair bit to do.

I think the clamp might need a bit more fiddling to get it right..

Why holesaw the end of a short piece?

Why not holesaw the middle of a longer piece?

Half the cuts on the tube, half the operations with the notcher, and probably a longer life out of the holesaw.

Blackjack said:

Why holesaw the end of a short piece?

Why not holesaw the middle of a longer piece?

Half the cuts on the tube, half the operations with the notcher, and probably a longer life out of the holesaw.

Click to expand...

I have tried that once or twice but have found that with the holesaw the same size or smaller than the tube. When it cuts through the top half, the bit cut off, falls in the tube and snags the holesaw as it goes through usually ripping teeth off it.

I did have thoughts of some sort of automatic feed and maybe compressed air to blow the offcuts out.

Using 1 1/4" OD 12 gauge CFS3 tube with a 1 1/4" holesaw at 150-180 rpm, it seems to work OK.

Keep the pilot drill in the hole saw. That keeps the cut out centred.