Compressed gas to cut aluminum foil

[KirkOden]

As part of our process we apply an adhesive lined foil backer to one of our products. Currently we use a glorified utility knife and drag it across the product to cut the foil. This works great the first 50 or 100 times until the foil tears instead of cuts, wads up on the cutter, causing scrap and downtime. My thought was since the foil isn't very thick (maybe a little thicker than heavy duty aluminum foil you use for cooking) we could possibly use a high pressure air nozzle (150-200 PSI possibly). I can't seem to find any real world applications but thought I would see what everyone thought.

 

[Jboggs]

Maybe others have seen cutting with high pressure gas, but I have not. I have seen cutting with lasers, water jets, etc. Maybe you just need a heavier duty rotating knife edge to cut like a shear.

 

[KirkOden]

The problem is the adhesive builds up on the cutting edge. That is why I was thinking if I could do something with that did not contact the foil we wouldn't have to deal with that issue.

 

[rb1957]

could you heat (slightly ) the knife blade (and melt the adhesive) ?

haven't heard of compressed air being used for this (water certainly) ... you could try it and see ... I think it'll tear worse than a gummed up blade (but I could be wrong).

maybe a laser (but not a "laser") ?

another day in paradise, or is paradise one day closer ?

 

[dbill74]

What about using a circular rotating blade? Like a pizza cutter and brush/scrape glue off the side of the blade not in contact with the product.

From what little I know of "high pressure" cutting jets, be it water or air, they use an abrasive in the stream tht actually does the cutting.

 

[chicopee]

Since you cutting knife works 50 to 100 times before the glue clogs up the cutting edge, devise a scraping tool that will clean up the cutting edge.

 

[chicopee]

For scraping tool, I would look at compressed air first.

 

[EdStainless]

Water jet cutting often does not use abrasive. It is commonly used to cut foods, even ones that are moisture sensitive like crackers.
It would be easier to use a rotary knife with a wiper/blowoff system to keep it clean.
Look at the cutters that they use in sewing (olfa). It might make sense to have a quick change system to swap out cutters then clean and re-hone the blades offline.

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P.E. Metallurgy, Plymouth Tube

 

[btrueblood]

Switch to a snap-off type of utility blade, and instruct the workers to snap the blade (exposing a fresh tip) every 40 cuts or so.

 

[MintJulep]

Air jet cutters are apparently used for textiles, so it is a thing.

 

[3DDave]

Try using a microscope to see what happens to the cutting edge as an experiment for each set of 10 cuts or so until the cut fails, to see if it is adhesive buildup or blunting of the cutting edge.

Information that is missing is whether the current method uses only the tip of the knife pressing against the product or if the foil is suspended above the product and the blade is on both sides of the foil.

The trick with air/waterjet cutting is the need to have a place for the working fluid to escape after it passes through the cut material.

I'm thinking the rotary knife is worth a try as it causes material failure in the aluminum in a way that forces the adhesive away from the blade.

 

[KirkOden]

3DDave the gap is also a concern I have. The two pieces are touching when the foil backer connecting them is cut. I will look into rotary cutters like many have suggested.

We do currently use a snap off tip style knife. The issue is that it is not very predictable as to when it will get dull, it just tears the foil and causes scrap. Then we have to change the blade. It could be 15 min it could be hours. I think the rotary style cutter may be a better option so that we can wipe the adhesive off if needed.

 

[Compositepro]

Oiling the blade will often solve adhesive gumming problems in applications like yours. WD-40 and LPS-1 work well. Apply with an oiled cloth.