Sheet notching tool?

[KemppiFrog]

Hi guys, bit of help here. There was some comment a couple of years ago, which included some notching heads for use in a press. Made by a Polish outfit. I have spent a bit of time on the bay and here. So far nothing.
Anybody got a lead?
Thanks
KF

 

[Tigman]

Type in corner notcher in the search bar quite a few threads come up !

 

[Screwdriver]

You already have a press? If you want a square notch for a box fold, you'll need a pretty big square punch and build a jig around it. I might have a suitable tool, depending on exactly what sort of notch we're talking about.

 

[KemppiFrog]

Tigman; Duh! Corner was the word I missed out.... But nothing there.
Sdriver: I will probably make one. Typical notch is in 1mm galve sheet up to 40x15 mm legs, but mostly 10x10mm or 25x10mm. For box folds in lighting backplates.
The press is an air driven one I made up at around 6 ton. I figured to hinge the 'punch' section to give a scissor action in the manner of a bench shear, so the cut is progressive. I have some unused square section lathe tools that could be the cutting edges. One for a rainy day. Thanks for the offer.
KF

 

[Paul G]

I did some 1mm stainless boxes a while back and made a tool for my fly press.
The press is a 6 ton but the effort required was nowhere near that. Push with one finger was enough.

Bottom tool was two pieces of 1/2" HSS lathe tool and the top tool a piece of 3/4" HSS on end held in a V block.
The top tool was ground to an angle so that it pierced the sheet and cut towards both sheet edges as the
tool went through.
The 3mm strip on the top is just a back stop.

HTH
Paul G

 

[KemppiFrog]

I did some 1mm stainless boxes a while back and made a tool for my fly press.
The press is a 6 ton but the effort required was nowhere near that. Push with one finger was enough.

Bottom tool was two pieces of 1/2" HSS lathe tool and the top tool a piece of 3/4" HSS on end held in a V block.
The top tool was ground to an angle so that it pierced the sheet and cut towards both sheet edges as the
tool went through.
The 3mm strip on the top is just a back stop.

HTH
Paul G


View attachment 74484

Thanks for that Paul, looks good.
Mine needs to be longer on one leg, hence the hinge idea to locate the cutting die., and I might make the lower section flush with the deck.Be easier to fit the stops.

 

[Paul G]

Thanks for that Paul, looks good.
Mine needs to be longer on one leg, hence the hinge idea to locate the cutting die., and I might make the lower section flush with the deck.Be easier to fit the stops.

When I have used this to cut bigger notches I simply use it nibbler fashion, taking 4 bites to cut out 30mm square for instance.

 

[Paul G]

Another view if it helps with the backstop plate off, showing how the 1/2" HSS sits on 1-1/2" bar, clamped by 2" bar.
Also the angle on the punch
It was just a case of making it from what I had in stock.

 

[KemppiFrog]

Ah! I was wondering how you clamped the HSS lower cutting bits. Neat. Looked in the box of odd lathe tools and found a bit of HSS that will do for top cutting tool. Might get it roughed up on Saturday, ready for the next batch in the coming week. Thanks again for the input.
KF

 

[KemppiFrog]

Well, I did spend a bit of Saturday roughing up the tool. Used the hinge idea and tried it in the hydraulic press this evening. Grabbed a bit of sheet and pumped the handle. Slight bang and I had a nice clean cut. Then noticed that the bit of sheet was 1.5mm... So a good test. I need to mod the air driven press to take the tool, but will put up some photos tomorrow. Bit dim out there now.

 

[Screwdriver]

Hope you're wearing eye protection until those hardened edges prove reliable.

 

[KemppiFrog]

Hope you're wearing eye protection until those hardened edges prove reliable.

I tend to wear glasses for close work (increasingly..) so small bits would be OK. Though in fact, the angles involved would not put me in the line of fire. But thanks for the warning. Judging by the sparks from grinding the top cutting tool, it was probably an old file, so possibly a bit fragile. Several of the tools in the big box I got with the lathe seemed to be made from files. The lower two edges are standard HSS stock.
But, quite pleased at my first go at a corner notcher. Probably around two hours of work and bits from the bin.
KF