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chrisinestes
12-25-2014, 05:38 PM
It's probably a small percentage of people that would think a bunch of chunks of steel was a great Christmas gift... Probably a high percentage here.

I got 40-50 chunks of steel round bar, & I like it! They're about 1 1/2" dia. by about 18" long. They came by way of my brother, from a guy that got them from the estate of a machinist in Wyoming.

Word is they're highway concrete slab expansion joint pins. Here's a link to a pic off Google of what I think they seem to be. http://www.pavementinteractive.org/wp-content/uploads/2008/06/Dowel_bars11.jpg

Anywho... They're supposed to be good machinable steel. I have visions of cannon barrels dancing in my head... Any ideas for me what the alloy may be?

Chris

Willy
12-25-2014, 06:13 PM
From what I've seen in my limited(13 years) experience working for a highways maintenance contractor they are plain carbon steel bars, think re-bar, that is usually available in 3 or 4 grades. Grade 40-75. The grade number indicating the yield strength in psi., grade 40 being 40,000 lbs. psi yield strength.
I'm also assuming the higher grade numbers reflecting a higher carbon content. Grade 40 is also specified for applications that require bent bars.
Not much help with the finer details of the alloy but this should give you a general idea of what you have. Maybe look up the various grade numbers along with the description of "tie bars" as that was the term we used.

Blazemaster83
12-26-2014, 12:29 AM
That is a bunch of stock! I wish I got that for xmas, nice score

boslab
12-26-2014, 12:49 AM
If you want to make cannons out of them I think a slice off the end sent to someone who can analyse them might be a good idea, as Willy said the bridge rollers I have seen were not anything fancy.
You don't want to make something that the coroner won't be calling the gift of steel, he'll be calling it the riddle of steel if it splits!, I (we) don't want any mishaps, even a good scrap metal dealer can zap it for you(handheld XRF gun)
If your really stumped face a piece, slice about an 1/4" and post it to one!
Other than checking it's a usefull pile of stock to have around, you never know what you will think up for it!
Mark

vpt
12-26-2014, 09:39 AM
Any "amount" of some sort of stock is useful!

I got about 200 sticks of 1.25x1.25x5/32" square tubes all around 45" long some time ago. I have used to make everything from trans cross members to running boards and even small chunks for repairs.

I wish I had a supply near the same of solid stock for machine work.

First thing I would do is throw one in the lathe and see how it turns both at the OD and towards the middle like mentioned. See how it does and know more of what I have.

Peter.
12-26-2014, 10:04 AM
I got one of those expansion joint pins off a railway project. It won't rust but it seems far too magnetic to be stainless. No idea what it could be so I use it for making spacers.

Seastar
12-26-2014, 11:11 AM
If you look here
http://ntl.bts.gov/lib/43000/43500/43503/DowelLoadGuide.pdf
It describes the types of steel used in highway expansion joints.
They are generally, in the case of the plain carbon steels, A663, A615 and A36.
A663 is a normalized low carbon steel, A615 is an embossed or deformed low carbon steel (rebar)
And A36 is ordinary low carbon structural steel.
You probably have either A663 or A36
Since A36 is the most common that would be a good guess.
You could use any of these for cannon barrels if you use enough wall thickness and limit them to small amounts of black powder.
There are tables online that give the approximate numbers.
Bill

chrisinestes
12-26-2014, 01:18 PM
Thanks for the replies and suggestions... I'll do some reading and some shop testing and get a piece officially tested when I get to a bigger city. I'll ley you know what I come up with.

Thanks!
Chris

Black Forest
12-26-2014, 03:01 PM
If you all want a supply of round steel just go to your local hydraulic repair house. I get all I want free from my guy. From 16mm up to 100mm. Just check it for hardness before you plunge into it! Some of what I get is quite hard on the outside. Some is not hardened. Alot of it will have a slight bend in it. If I come onto a a rod that is hard I have found if I take a deep first cut of 4mm off the radius I get under the hard part mostly. Not always. I use a Walter WNMG 080408 nm4 wap20 on the tough stuff.

Because I have these wonderful Walter facemills I have been guilty of squaring up a piece when I didn't have anything handy in the right size square stock.

LKeithR
12-26-2014, 05:34 PM
If you all want a supply of round steel just go to your local hydraulic repair house. I get all I want free from my guy. From 16mm up to 100mm. Just check it for hardness before you plunge into it! Some of what I get is quite hard on the outside. Some is not hardened. Alot of it will have a slight bend in it. If I come onto a a rod that is hard I have found if I take a deep first cut of 4mm off the radius I get under the hard part mostly...

Just a followup to what is posted above. Most general purpose hydraulic cylinder shafts are made of 1045 steel which is an excellent material to machine. Heavier duty applications will use better steels but they're not as common and the hydraulic shops I've dealt with tend to want to recycle them in some way. If you're getting it for free you're likely getting 1045.

There are two common surface treatments for cylinder shafting. First is CPO (Chrome & Polish Only) which has a thin layer of hard chrome plating on the outside surface--just about any machine can remove it with little difficulty. Second is IHCP (Induction Hardened & Chrome plated). In addition to a layer of hard chrome plating it also has a hardened skin which can be up to .125" deep. As Black Forest says, if your machine is beefy enough you can peel it off in one pass but you must get the tip of your tool into the softer inner core.

An easy way to see if you've got CPO or IHCP is to give it a decent whack with a hammer. CPO will show a dimple proportionate in size to how hard you hit it--IHCP doesn't take much of a mark unless you really strike it hard. If you have samples of both it's really easy to see the difference...