Check out this video we made on how to dial in your Torchmate table. The best cut quality that we could achieve on 1/4" mild steel was 40 amps, at 20 inches per minute, with a .06" cut height. We chose these settings for the sharp corners, VERY minimal amounts of bevel, and the dross that can be easily scraped or flicked off. The finished part easily stood on its own on my desk for the picture. We later performed a test to get some production settings recorded. We concluded that 80 amps, at 90 inches per minute, with a .08" cut height gave us the best cut quality at the fastest speeds. The bevel angle on this part was not good enough to stand vertically, but was still very good. The corners at 80 amps were still sharp on the top of the part, but had additional blow out from the increase in amperage that left the corners looking a little rounded. I posted up close pictures of these parts below the video. Let us know in the comments below what you think about the settings that we chose and how you would improve them!
20ipm is a crawl but slow and steady wins the cut quality race. Cudos to you guys for posting the results. Nice to see its not always about how fast you can go. I wonder if there's a cut quality difference in HR and HRPO? Does the mill scale affect the torch flame in any way? It looks like the second piece is HRPO.
HRPO cuts like a dream. Very little to no dross along with smoother tooling of the edges. Pay to play gents.
Hot Rolled Pickled & Oiled. Still hot rolled but no mill scale, and has a thin layer of oil to prevent corrosion. Easily wiped off for painting or finishing. IMO, considering the hassle of removing mil scale, it's worth the small price difference.
What amp consumables were you utilizing in the torch head? I was wondering if there would be a difference between the 40A or 6oA consumables or if you would just utilize the 60A for all variations.
For all the amp ratings we used the corresponding nozzle for those ratings. You dont want to use a 40 amp nozzle at 60 amps because it is like driving a VW BUG though a hallway. You can go under but not over.
I've been using P&O for over a year now. I won't go back to HR steel. Less dross, cleaner edge and dross is easier to remove. I do still soak the parts in vinegar sometimes and then the dross that doesn't disappear literally falls off with the wipe of a rag. Also removes the oil and gives it a nice finish ready for paint
I am definitely going to have to try soaking my parts in vinegar. I've heard of certain acids doing the job, but I've never heard that a house-hold item like vinegar could work.
Sure, that's been my understanding of how to properly set up a torch head. I was just confirming that when the 1/4 plate was cut at the slower 20 IPM setting utilizing 40A that the consumables utilized were still the 60A variety. I have a couple of upcoming projects that would benefit greatly from the square edge created by the slower cut speeds. Thanks, very helpful tip!
don't use the apple cinder vinegar, i didn't have luck with that. Muratic acid works the best but after getting a whiff of it, i don't want to use it anymore. I bought a plastic tube and 2 gallons of regular vinegar for $2. The first use was the best, but it wears down quickly after that. But it still works good and dross falls off pretty quick. so i soak it for 12-24 hours, then rinse it and wipe it off. I have a second bucket that i drop the parts in to break off the dross. Then 90% of the dross is gone. I like this because I can just rinse it in the laundry sink. Just gotta get a better bottom part to catch dross so it doesn't go down the drain.
I never mismatch consumables and operating amperage. The video shows the 20 ipm cut speed at 40 amps with 40 amp consumables in the torch. The only reason you would operate at a lower amperage with a higher rated consumable would be out of the sheer convenience of not changing out the consumables. Your cut quality will suffer though.
Yes ... because all it would do is blow out the under rated one so if you are going halves then go up a rating.
How does HRPO compare to Cold rolled? Been using cold Rolled 16 gauge for my projects, don't like dealing with regular Hot Rolled because of the mill scale.
I use sodium bilsulphate, comes as a 20kg sack of white granules. Mix about 8 cups in a 150 litre container and dross wipes off the next day, if it doesn't, add another cup. Brilliant stuff, cheap as chips. Will cause a very small slight sting if you have a cut on your hand and dip it in, but I have done it a million times. The pool companies use it to raise or lower pH, I forget which Cheers Larry Cameron