OK so here is what I use for 11 ga P&O. Speed is 60 ipm, 35 amps, and pressure is 90 psi. Let me know if that works for you. I get consistent clean cuts and VERY little slag/dross.
diverd50, I actually used that! I know it sounds unreal but I did. I tried so many combos that my head started to hurt. It is like I said “I have never had this much trouble before”. I worked at a metal fab shop for about 5 years with all kinds of different metals. We had some sheet that was so soft it was hard to weld, and then again we had some 1" sq tube that would break after galvanizing. I listed 9 different combos but there were more including yours. Your air, amps and feed are so close to where I started. I am going to take a piece to where I used to work and have them test it for me. I will post the results.
Great let me know how you make out.
For what it’s worth, the P&O process doesn’t change the hardness of the steel. It’s still the same base metal and grain structure as before it was pickled and oiled.
I’m not saying that it’s not different than the hot rolled sheets you bought before and after, but it’s not different than the hot rolled sheet it was before they removed the mill scale with the P&O process.
Good luck, dialing in cut conditions was one of the parts I found most frustrating about running a tube laser.
MrHaNkBoT, Thank you, any information is welcomed. I understand about metal alloys, I do! I even lowered the water in the pan thinking that it was too high thereby cooling the sheet too fast. No! I did not drain it all, left about 1". But this metal didn’t care about my settings it just would not cut without a lot of dross. I worked at a Company that made steel confinement fencing, steel slat flooring, feeders, just a few of the products. We had some tube come in so brittle that during welding and even after Galvanizing it would break. Just weld in some stays, drop on floor and it would break. After Galvanizing just strapping it down would break it. We had some 12ga sheet come in that was so soft that it was hard to weld, it formed great. There was just some thing wrong with this metal. I gave up on this metal and took it back and informed the Seller of the problems and they said that they would check into it. I got the first 2 sheets off the new bundle. Thank you for the Info! I hope the reading of this didn’t come off like I was angry! I used all the info that I got from replies on the forum, it is just that nothing worked. 1 setting was close to Fortifyfabworks, I was close to diverd50 and was was at 90psi. Thanks again to all that tried to help me!
Any time man, if you need to just post on here. We can help if possible
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What design software are you using to create the setup, tool path, speed, etc?
I use Fusion 360. With a lot of intricate cuts, I have found that in the setup,it helps to check the “smoothing” box and select “roll around corners” and NOT select “keep edges sharp”. This allows the cut to run at a more continuous speed.
GPow, I use Fusion 360 too, and I keep the roll around selected. Thank you for that information!
check your ground
Thank you timmmillar1! But I have checked every thing I could thing of. The only one thing that I have not tried is a lower amp rate. I have a couple of small pieces left of the P&O. So I am going to lower the amps. I can’t slow the feed rate because of the quoted piece price. This is part of what I have tried. I may have to try 25amps and lower. I have clean dry air, plenty of air flow at all settings, the clamp is on the metal, the grounding is good, all connections are good, I am not getting any kind of electrical interference.
This is the only metal that I have had trouble with!
- Cleaned with Lacquer thinner, wiped clean, both sides and allowed to dry completely.
- 30amps, 25ipm. No help
- 30amps, 15ipm. No help
- 33amps, 40ipm. No help
- 35smps, 65ipm. No help
- 27amps, 28ipm. No help
- 45amps, 30ipm. No help
- 45amps, 100ipm. No help
- 45amps, 90ipm. No help
- 45amps, 65ipm. No help
- If I slow down below 50ipm I may as well pay the customer for letting me run there parts. LOL!! I don’t drink but I may start…
- I give up. No help! With good metal it takes 25 minutes to finish 1 part. The program spaces the rectangles apart to allow cooling. IE; Top row, bottom row, center row, next to top row, next to bottom roe and so on and this works on the Hot rolled. I wrote the program in 4 separate profiles. This way the part can cool for about 1 minute between each profile cut.
I do think the metal is too soft. I ran into something like this when I was working at a Company called Bainbridge Ent. We built Steel Confinement fencing, flooring, feeders, and farrowing equipment. The Company bought about 150 sheets of P&O 18ga. It formed and punched great but when it was welded it was like welding 24ga. and we had to lower the amps on the welders.
When we tested the metal with a hardness tester it tested below the range of where it should have been. when welded it would burn through very quickly. In another instance we had metal that came in so hard that after it was welded and galvanized it broke like glass. I have permission to switch to 10ga Hot rolled to finish this project. We have finished that order and are ready to start the next. So that is what I am left with for now. We have 11ga Hot rolled coming in this week. Thank you to everyone that contributed Information…
That gnarly dross looks like air cut stainless. Did you ever figure out what this was all about?
Not yet! I have a little of the material left so I plan to do some sample cuts again with lower amps.
P&O steel will never weld correctly or cut correctly it has oil all through it.
Steel is not a porous material. I’m not sure what you mean by “oil all through it.”
The oil can be wiped off of the exterior of P&O sheets the same as any other oily steel.
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