We've just put a new bush in one of the top bucket pins on this Cat 943 Traxcavator, however it really needed a new pin to go in with the bush (which was non-existent!). Can't get new pins here in Australia as they are ex-USA from Caterpillar at a stupid price, plus air freight. So I want to get some machined up locally. It has the usual "4 in One" bucket/blade and it's the topmost pivot pin that pivots the bucket part (teeth) up & down. The pins are in the order of 200 mm long and 50 mm diameter. I can weld my own retaining tangs on. My question is - what type of steel are these pins made from? The existing ones look and feel a bit harder than mild steel.
Most pins are made out of a hardened chrome shaft. Most metal supply houses can order it in common metric and standard sizes, or, if you're very lucky you could find and old hydraulic cylinder with the proper size rod and use that. I'd bet that 943 uses a 2" pin where it's an American designed machine.
I'd (no expert) go with stressproof 1144 or ETD 150, easy to machine and tough. 4140PH or 4340 if your wanting a bit "more" out of the pins. These materials aren't the most readily weldable though.
Thanks guys. The existing pins do have the retaining tangs welded on and the guy that will be doing the welding bit is a fully qualified boilermaker/welder (he's a darn good one as wel!) So if it's been welded previously, I'll leave that task to him as he seems to be able to weld dunny paper together!!
The 1144 is pretty weldable, but the 4140PH and 4340 just need a controlled pre and post heat. Should be able to find info about that elsewhere. What makes them nice to machine and tough makes them do funny stuff when welded.
Most pins are EN24t steel (4340), but also case hardened! You can use it as it is with fair results, but if you want o.e.m quality it needs to be hardened! A local machine shop may have some case hardened 2" bar in stock and be albe to make a pin from this! This is what i do in some cases Aiden
The pin will be 4140 or very similar that has been induction hardened and tempered. Bearings are usually carburised EN14. You may find Geographe has pins on the shelf in Perth. If you need to I can machine you a pin and point you to where to get it hardened. If the bearing was non existent you will likely find the hole needs to be welded and machined.
Are they part number 8V7419? If so, RD Williams and Don Clark tractor are showing stock.