Pin material ?

I wouldn't sweat it. Just keep on eye on it for now. See if it deforms at all in use. I seriously doubt they're anything more than grade 2. You can get Clevis pins from Tractor Supply or Ebay for that matter. That is if I understand which pin your talking about correctly.

I use grade 5 or grade 8 bolts as feed stock, depending on required strength and hardness. - or even grade 3 if that is all that is required. I go by the head markings to know what I have - - -

It's the link that connects the lower arm to the upper arm that does the actual lifting . I have to remind myself that it's only function is lifting , it doesn't have any pulling load .

This didn't start out as a bolt , it's from a 1" piece of round stock. Bolts are way too expensive to use as lathe stock .

I use grade 5 or grade 8 bolts as feed stock, depending on required strength and hardness. - or even grade 3 if that is all that is required. I go by the head markings to know what I have - - -

----------------------------------- I do that too. Threaded rod couplers are also useful stock for custom parts. Unlike iron pipe, the threads on brass pipe nipples usually run true to the OD, as mandrels for modifying threaded fittings.

Rolled bolts' threads and shanks are never quite parallel so I buy high strength bolts long enough to chuck the shank with the threads exposed and turn the threads to the next smaller 5C collet size, and center-drill the end. When reversed in the collet the shank usually runs true enough for high strength, low accuracy projects like tractor parts. I also center-drill the head, just in case it needs center support, and may face the bearing side of the head truer than as-stamped or turn a locating step in it to center in existing oversized or worn and rebored holes.

The currently pending bolt project is threading a 3/4-10 bolt shank to

Grades 5 and 8 can be turned and threaded at reduced speed with HSS lathe bits.

While researching diamond grinding I found advise that dry grinding steel is OK below 4500 surface feet per minute, above that use coolant. Perhaps that's why Darex diamond wheels last.

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I paid about $1 per inch for a remnant of 1" diameter 4142HT a decade ago. Grade 8 bolts are around that price now, and more importantly you can buy only as much length as you need. They aren't that expensive when the alternative is turning down most of the stock from head to shank diameter.

I find bolts I have are a lot cheaper than going to the metal store to buy new metal - and with bolts I know what I have.

Who said anything about buying stock ? Not that I don't buy stock when I have a project that requires something specific , but probably

Who said anything about buying stock ? Not that I don't buy stock when I have a project that requires something specific , but probably

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I modify bolts when I need small pieces of machinable steel of known (claimed) higher strength rating for calculations, especially with a larger head and for lifting. They may need non-standard shank and overall lengths, for instance the bolts in double shear that sandwiched the gantry track channels to the splice and hanger plates and had to let the trolley wheels pass. They were threaded just far enough to let the nut pull tight, and cut off flush with its outer end.

Much of my stock came from auctions or scrap bins and unless labeled I can't assume better than A36 properties. If the part doesn't need a larger head I generally make it from O-1 drill rod but I don't trust my heat treating skill enough to harden and temper it for other than cutting tools.

I tested the bending properties of a 1/4-20 Grade 8 bolt. The rolled threads broke off with a brittle fracture, the shank bent double without cracking. This is why I cut custom threads on the shanks of long bolts. I save the cut-off original threads to make setscrews and tapped hole center locators. jsw