I have made welding projects with flat suspension springs in the past. I used mild steel rods and they almost always broke loose at the weld - a bit hard. I did make uprights for a grill guard many years ago. When I hit something the spring bent back into the hood.
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What steel might this be?
- Thread starter JRT
- Start date
HSS vs. Carbide didn't seem to make a difference in the surface finish. How do I test for the level of carbon in it? This is pretty rough. I started turning down a little piece of CRS to make a draw pin for my Rusnok mill and it didn't cut much different. Maybe I need to readjust my tooling with a center in the spindle, not sure. If it gets any better I'll post it here. -John
Did you mess around with feeds and speeds?
From my rank amateur view it looks like it may have been too fast for HSS and too slow for carbide.
But it also could be crap steel that won't give a really good finish.
A quick test for carbon content is to do a spark test. There are lots of videos out there if you are not familiar. Basically the higher carbon steels will throw sparks differently than low carbon steels. I sometimes do a comparison to something that is a known steel or at least a known type.
Touch the test piece to a running grinder and observe the sparks. How many and the color. Also watch to see how they give off secondary sparks as they die out. Then do the same thing with something you know is hard, like a drill bit or tap. I keep a couple of broken ones near the grinder just for this purpose. For me this works pretty well on plain carbon steels but gets a little iffy with aloys.
Another test would be to saw off a few slices maybe an 1/8" thick and heat treat them. Try different heat temps from cherry red to bright white before quenching. Once cool put the disk in a vise and hit it with a hammer to see if it bends or snaps. Lower carbon steels will be more likely to bend and higher ones will be hard and have a tendency to snap.
All this is pretty crude analysis but sometimes it is all us hobby guys have the ability to do.
From my rank amateur view it looks like it may have been too fast for HSS and too slow for carbide.
But it also could be crap steel that won't give a really good finish.
A quick test for carbon content is to do a spark test. There are lots of videos out there if you are not familiar. Basically the higher carbon steels will throw sparks differently than low carbon steels. I sometimes do a comparison to something that is a known steel or at least a known type.
Touch the test piece to a running grinder and observe the sparks. How many and the color. Also watch to see how they give off secondary sparks as they die out. Then do the same thing with something you know is hard, like a drill bit or tap. I keep a couple of broken ones near the grinder just for this purpose. For me this works pretty well on plain carbon steels but gets a little iffy with aloys.
Another test would be to saw off a few slices maybe an 1/8" thick and heat treat them. Try different heat temps from cherry red to bright white before quenching. Once cool put the disk in a vise and hit it with a hammer to see if it bends or snaps. Lower carbon steels will be more likely to bend and higher ones will be hard and have a tendency to snap.
All this is pretty crude analysis but sometimes it is all us hobby guys have the ability to do.
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- Apr 30, 2015
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Steels often tear like that when cut- although it looks like your cutting tool might have too sharp a nose radius
Use a sharp, rounded nose tool and cutting fluid/oil for a smoother finish
Use a sharp, rounded nose tool and cutting fluid/oil for a smoother finish
Great info, thanks!... and I did change speed of the lathe but not the feed as I haven't yet learned how on my lathe. Looking into that today actually. I have a little Atlas 618 and it was running at 350'ish. the slowest it can go without engaging the back gear. I do have a little 2x42 belt grinder so I'll maybe look into the spark test today too! -John
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