Stainless and rust spots

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ROKCRLER
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Stainless and rust spots

Post by ROKCRLER »

Cutting 16ga stainless, 45a shielded...
I cut 14 pieces and only a couple of them have some rust spots show up.. what would cause this?
I haven't cleaned my slats between materials, i "think" it might be from grounding maybe?
I hate to have to sub stainless work to laser and thought i'd get y'alls input.

Thanks.

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Re: Stainless and rust spots

Post by acourtjester »

if they are ruff texture I would say grounding arc overs. Why not clamp the work lead directly to the stainless in a place that does not affect the finished product.
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Re: Stainless and rust spots

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Its contamination caused from your stainless coming in contact with mild steel whether its your racks or tools or whatever. When loading your table with stainless set it down gently and if you have to move it pick it up to do so. Don't slide it over your racks and scratch it. This will remove the oxide layer that protects it from the atmosphere.
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Re: Stainless and rust spots

Post by ROKCRLER »

acourtjester wrote: Fri Sep 24, 2021 4:33 pm if they are ruff texture I would say grounding arc overs. Why not clamp the work lead directly to the stainless in a place that does not affect the finished product.
Ground is on the star bolt, I'll put the clamp on the material on the next cut to see if there's a difference...thanks AC.
Blackslacks wrote: Fri Sep 24, 2021 4:43 pm Its contamination caused from your stainless coming in contact with mild steel whether its your racks or tools or whatever. When loading your table with stainless set it down gently and if you have to move it pick it up to do so. Don't slide it over your racks and scratch it. This will remove the oxide layer that protects it from the atmosphere.
We loaded and unloaded extremely carefully to not scratch.

Normally I don't worry about it since I usually DA the parts, but these have to be raw.
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Re: Stainless and rust spots

Post by adbuch »

Those look like arc burns to me. I agree with Tom - try connecting your work lead clamp directly to the material you are cutting. I happen to use a magnetic "ground clamp" (earth lead clamp) attached directly to the material I am cutting. This could also help minimize any marking from your clamp. Or place a scrap piece of your material on either side of the ss sheet where you are clamping. Thin copper strips may also work well.
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Re: Stainless and rust spots

Post by djreiswig »

Magnet isn't going to work on stainless. I have a magnet on my work lead as well. On stainless I clamp a pair of vise grips on a corner and stick the magnet to them.
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Re: Stainless and rust spots

Post by adbuch »

djreiswig wrote: Sat Sep 25, 2021 5:31 am Magnet isn't going to work on stainless. I have a magnet on my work lead as well. On stainless I clamp a pair of vise grips on a corner and stick the magnet to them.
Good point. Thanks for pointing that out.
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Re: Stainless and rust spots

Post by ROKCRLER »

Update.
So it turns out all the spots came off easily with alumabright. no pitting so i dont think it was arc marks, more than likely when we wiped them down and stacked them. The second batch, we wiped down with clean rags and did not stack them and zero spots..
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Re: Stainless and rust spots

Post by acourtjester »

Thanks for the report back :Like
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Re: Stainless and rust spots

Post by adbuch »

Yes - that's good to know! Happy to hear you've solved your problem.
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