Author Topic: sheet metal air shears  (Read 243 times)

Offline picclock

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sheet metal air shears
« on: August 15, 2019, 11:43:43 AM »
i have just got one of these from Aldi  :wack: for cutting up some thin (0.6mm) sheet steel. However the kerf from the blade comes out to one side and prevents it from working properly. It also appears impossible to stear in a straight line .. . (though it could be pilot error ).  There does appear to be about 0.4mm clearance between the moving centre blade and the two fixed shear blades, which I could reduce by taking a bit off the fixed blade spacers if that is likely to fix it.

I would rather try to fix it myself than return it as I suspect only a refund would be offered. 

Any info much appreciated.

Best Regards

picclock
Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline picclock

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Re: sheet metal air shears
« Reply #1 on: August 16, 2019, 07:10:26 AM »
Removed blade head and moving blade to find that it had been ground at an angle. Reground high side of blade square and also reduced size of hardened spacer in my mill using a conical grindstone - it was very hard. Reduced blade clearance to 0.1mm.

The difference in performance was astonishing, and these corrections have dramatically improved the tool, which now cuts in the direction you tell it too, and does not jam up on the kerf.

Best Regards

picclock

Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline awemawson

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Re: sheet metal air shears
« Reply #2 on: August 16, 2019, 07:21:50 AM »
You may well find that it doesn't cut as well now on thicker material.

IIRC the shear gap needs to be 10-15% of the material thickness
Andrew Mawson
East Sussex