A question for the motorheads...

[mjarus]

It just hit me... there is a huge auto salvage yard not far from my house. So... what would be good to pull for machining. As always I could use more metal!

Does anyone know what type of steel are in truck leaf springs? I read that the shaft on transmissions are a good source of steel... any info on those?

I have also seen people use windshield wiper motors for a power x feed. What else could you pull and come out ahead of buying raw stock? This place is pretty darn cheap... full motors for $150. Not that I would trust one in my car given my mechanical skills, but you get the idea. Leaf springs are only $19.81.

mjarus.

[PROTOTRAKFAN]

Leaf springs are incredible hard and tough. Put it this way - along time ago I had some 30 -06 full metal jacket rounds. They penetrated right through some 1/2 thick cold rolled steel at 50 yards. They barely made a mark on and old leaf spring we had !!! I dont know what you are making but, stock is usually one of the least expensive items that must be purchased....
Patrick

[mjarus]

Well I guess perhaps thats a little too tough for my purposes. A 30-06 is an "arm cannon"! Im a newb just looking for some metal to have around to practice on before I get "serious" with a project. I finally got my small mill set-up, metal bandsaw and I think I am going to order a lathe tomorrow.

In setting up my mill/practicing I have gone through about $70 worth of 6061 aluminum... it ain't cheap around here and it sure isn't easy to find for the hobbiest. Ergo I am always thinking about sources to feed my newborn hobby.

mjarus.

[WhiteTiger]

One thing that's good if you can get it cheap is old mcpherson struts (or just the inserts). nice, beefy guide rods in modest lengths. Be great for small routers

The input shaft for a manual trans would make a nice spindle; hardened, already splined on one end, most have several diameters already ground and if you get a matching dead clutch disk you have a drive hub for it ready made.

Lets see, what else is promising.... an AC clutch pulley could be usefull lots of ways.

Electric seat motors have lots of oomph, and some would be good sources of small gear reductions.


Tiger

[High Seas]

Has anyone tried an auto ac unit for a vacuum pump? Old fridges work - but as long as, "Its Midnight at the Wrecking Yard!"
I'd better duck - that was another cheap chord!
Jim

[One of Many]

Best to stay away from materials you cannot cut with a file, unless you intend to grind it into shape. Scrap yard materials if unidentifiable in its previous life can still be a great deal. The problem I have had in the past is having someone else bring me materials without a clue to its current condition of uneconomically realistic to machine.

The last couple side jobs were old hydraulic cylinder rods. One was 2" dia and needed to be 1.950 x 17" long. I have read that a lot of this material is 1100 series stressproof, so it does not sound all that bad at first. These must have a case or induction hardened surface below the hard chrome. Fine if you have a cylindrical grinder, but conventional cutters won't do it well or efficiently. And I cringe at the thought of grinding on my lathe. This last one, I was given 4.125" round to make a custom coupler yoke. The heat treat after the chrome is at least a 1/4" deep. Slowing the lathe to get this to cut a .03 pass 6" long takes maybe 20 minutes. At $45/hr, 6-8hrs to get past the hard surface???? it just plain isn't worth it! Even if I was doing it for myself, I could save a days work on the project by purchasing known material. Not to mention if the scrap yard mystery material is readily weldable without creating further issues down the road.

It can help to take a file and a magnet with you. If the file skips across the material like glass, don't take it home unless you are looking for that as part of your spec. If the material cuts with a file, you can then determine other properties like cast, stainless, plated, etc. It is good to have at least some knowledge of what scrap thingies are made of. Many places on the web give some catagories to which #XXX alloys are most commonly used in.

DC

[WhiteTiger]

AC units work ok as vacuum pumps but you need to install an oiler on the intake side or it'll freeze up on you before long. Best setup I've seen used a bleeder valve upstream of the oiler to ensure minimal airflow for oiling.

You're right One of Many, IHCP stressproof and fatigueproof are very common as piston rod materials. Sort of rare in the larger sizes though for it to be hardened. Usually above around 3 inch it's just cp, at least in the longer lengths. Short stuff there's no telling from one part to the next.


Tiger

[One of Many]

Originally Posted by WhiteTiger You're right One of Many, IHCP stressproof and fatigueproof are very common as piston rod materials. Sort of rare in the larger sizes though for it to be hardened. Usually above around 3 inch it's just cp, at least in the longer lengths. Short stuff there's no telling from one part to the next. Tiger

I had figured as much. It didn't help that the 2" material was bent and one end cut off with a torch. Now that I recall, there was only .015 that needed to come off of the OD, not .050. No way I could get under the chrome at a consistant depth over the entire length of 17". Talk about a PITA material!..........

DC

[NC Cams]

Some material info - use as REFERENCE as there are options but these are typical for OEM applications (IE: non-exotic race stuff):

leaf springs = hot formed and spring temper 6150 or 9254
coil springs = how wound 6150 or 9254
con rods for pistons = 1053, 5160, "armasteel" castings
piston pins = carburized 1017, 5120, 8620.


"stressproof" and "fatigueproof" are trade names and technically oxymoronic as NEITHER condition can exist in nature once you apply a load to something....

If you want to practice, buy some 12L14 steel or 2024 aluminum. Both cut nicely and are real easy to learn on. Stay away from unidentified alloys as you usually have to do to much to them to make them machineable. Free materials often times are not worth the price you pay for them.

[One of Many]

Originally Posted by NC Cams "stressproof" and "fatigueproof" are trade names and technically oxymoronic as NEITHER condition can exist in nature once you apply a load to something....

"Less-susceptible-to-stress-fractures" just didn't look good on the brochure!

Like stain-proof, smudge-proof and Shatter-proof. To that degree, the practical side of truth can be pushed in marketing gimics. The no fault clause puts the believer in that claim, as the one whom had higher expectations beyond reasoning to legal-sleeze narrowly defined interpretation of those claims.

DC