# Cast Iron



## jolijar (Sep 4, 2010)

I have plans for a glow engine that uses cast iron for the piston. Where can I buy cast iron (I need about 8" of 3/4" Round) Or is there a substitute I could use?


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## Deanofid (Sep 5, 2010)

What Pat posted. Speedy Metals is a good place.

Dean


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## Tin Falcon (Sep 5, 2010)

here 
http://www.mcmaster.com/#iron-bars/=8pl5zu
I buy metal here if in the area or can have it over night at ups ground rate.


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## bearcar1 (Sep 5, 2010)

I have had very good service from metal express for my cast iron needs.
metalexpress.net


BC1
Jim


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## GWRdriver (Sep 5, 2010)

For a small weight like this I suppose anyone will do but for future reference, when I have needed a larger quantity of C.I. material (like a slab of grade 40 1" x 4" x 16") I shopped the net and found substantial savings over the usual suspects.


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## rickharris (Sep 5, 2010)

Small lumps - try to find some old sash windows the weights were cast iron - A plastic installer window may be able to help.

For bigger lumps Tractor weights.


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## Tin Falcon (Sep 5, 2010)

I read an article somewhere IIRC HSM magazine or a book they publish that suggests using cast iron plumbing fittings a pipe cap for a piston a coupler for a sleeve. have not tried it but should be a common item and save some machining time just a thought. 
OK found the 1 page tip, in Projects in metal book one pg 28, reprints from the first two years of PIM magazine. anyway the article recommends pipe plugs from the local hardware store as a source for small pieces of CI. these can be used for pistons rings eccentrics and cross heads according to the author. 
This was written 20 years ago before the advent of the big box Home improvement store in a town of any size and mass chinese imports but IMHO worth a try. 
Tin


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## shred (Sep 5, 2010)

Sash weights and barbell weights are about the lowest possible quality CI, but frequently good pieces can be had from them.


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## toolsrul (Sep 5, 2010)

Do a Dura Bar search. Good stuff & consistent in machinability.


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## GWRdriver (Sep 5, 2010)

Old sash weights, really old ones, were generally decent iron but the problem is they were often cooled too quickly and are chilled and hard, but some weren't. I've had some good ones and annealing will usually soften the hard ones up but as Tin says current barbell weights tend to be garbage and the more recent the production the worse they are.


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## winklmj (Sep 5, 2010)

rickharris  said:
			
		

> Small lumps - try to find some old sash windows the weights were cast iron - A plastic installer window may be able to help.
> 
> For bigger lumps Tractor weights.



These are gonna be hit or miss. I snagged 3 the other day at the scrap yard. They are cast iron but 1/8" in they seem like they are hardened. My little 4x6 bandsaw stopped cutting. I'm gonna toss 'em in the fireplace and try and anealing them otherwise they're gonna be useless.

Heard the same can be true for the tractor weights but you may get lucky and come up with some nice useable pieces.


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## itowbig (Sep 6, 2010)

car engine. a crank shaft from same


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## Artie (Sep 6, 2010)

itowbig  said:
			
		

> car engine. a crank shaft from same



I hadnt thought of this, once a crank has wrecked a journal its useless and also worthless, taking them away from the engine machining place would be welcome from their point of view.

One thought, cranks are usually nodular cast iron. Most of the stuff Ive bought from metal supply houses in past is spun cast and therefore a different grain structure and the carbon content on cranks seems a whole heap less while they seem pretty hard. Is this a problem? Anyone had any experience? Im off to grab a crank sometime today to play with. :big:


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## tel (Sep 9, 2010)

shred  said:
			
		

> Sash weights and barbell weights are about the lowest possible quality CI, but frequently good pieces can be had from them.



Might be different there, but I've used dozens of the things and all but one have been excellent iron, the one 'bad' one was still good iron, but badly chilled and hard to work.


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## bearcar1 (Sep 9, 2010)

Artie  said:
			
		

> Im off to grab a crank sometime today to play with. :big:



EEeeewwwww! Artie, that's WAYYYYY too much information. And a blighter your age. Ever thought of therapy? :big: :big: :big:

BTW, don't forget to wash your hands afterward.


BC1
Jim


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## bentprop (Sep 9, 2010)

There's an easy way to check if a sash weight is going to be of any use.
You give it a good whack on a hard surface to break it in half.If the inside is a nice matt shade,it's fine.If you have glistening pieces though,forget it.That's sand,which will q uickly ruin your cutting tool.I think Bogs gave that tip in his paddleducks build IIRC.


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## Cbowler (Sep 9, 2010)

I'm thinking about building a 2-stroke glow myself, for my next project, but what I've been pondering is- "Is cast Iron really necessary - unless the engine is going to see a lot of service perhaps not?".
Cole


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## bentprop (Sep 10, 2010)

> Is cast Iron really necessary - unless the engine is going to see a lot of service perhaps not?".



I would think hard aluminium alloy is probably better.That's what all the manufacturers of model 2-stroke engines use,and they last an amazingly long time,even when abused by dimwits not putting enough oil in their fuel.Unfortunately,those sort of grades of alloy are not normally available in small quantities,which is possibly one of the main reasons for specifying cast iron.Although for our sort of use,you can probably get away with 6061,which is quite easily sourced.my 0.02.


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## Artie (Sep 16, 2010)

bearcar1  said:
			
		

> EEeeewwwww! Artie, that's WAYYYYY too much information. And a blighter your age. Ever thought of therapy? :big: :big: :big:
> 
> BTW, don't forget to wash your hands afterward.
> 
> ...



Ooooooohhhm Jim....I ALWAYS wash my hands.......

I got my hands on a broken crank and stuffed it into the power hacksaw.... I didnt stay around to watch it just got on with other stuff.... then I pressed off the cam drive grear and placed it into the lathe..... whoa! That aint cast iron...damned hard forged steel...... doh *bang*

As you can see it was all rusty so it was hard to tell....












I should have looked harder..in the last pic of the thing in the hacksaw you can see the "seam", this is called the "parting line" and in cast cranks its very thin, as per the 2 halves of a mold meeting. In a forged crank it is very wide as in this example here..... it was very obvious after I went "What the ...??"

Ill try again.... dont forget these things have holes drilled all through them, thats why I went for a large crank and used the snout.... itll make a great press tool....

Cheers all

R


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## Blogwitch (Sep 17, 2010)

Just getting back to sash weights as a source for cast iron.

I have been using them for many years, and there is a bit of a technique to making it easier on your machinery.

Normal sash weights are cast with the hanging loop downwards, so all the dross and crap rises to the end opposite. I cut off about 3" at that dross end and discard what has been cut off, and most times, all the rubbish is then gone. Don't try cutting it with your bench tools, the hard skin formed over maybe the last century or even more will really test your cutting tools. I, using a small angle grinder, just score around the bar where I want the break, then just dropping it onto a concrete floor will cause it to break around the grind line, or maybe persuade it to break with a lump hammer. All safety rules should be applied. Using this method, I break them up into manageable billets of between 2" and 6" long, depending what it is required for.

Next comes to getting thru the hard outer skin on the lathe. You DON'T cut thru it, you get under it, and peel the skin off. I find that putting a cut on of anything up to 0.100" will get under the skin (it depends how misaligned the moulds were when they were cast) and you will be left with a nice machining, very tight grain, cast iron bar. I usually get a minimum of 13" long by 11/8" diameter, sometime a lot more. In cost terms, that would work out to almost 20 squid from a metal supplier, my usual cost is 30 pence each from the scrap yard, plus a little work getting it out of the rough. To me, at those sorts of prices, it is time well spent.

I suppose the quality does rely on where in the world you come from, and even the area you live in. Being very close to the Black Country in the UK almost guarantees I will get the best quality ones ever made. That is where it all started a few centuries ago.

Bogs


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## Peter. (Sep 18, 2010)

I'm depressed now because I just recently scrapped some 2" square wieghts about 3' long from some old windows I tore out of a school building. It did cross my mind that they might be machinable but I figured they must be rubbish quality since I'd never heard of it before. 

To add insult, I'm just about to buy some decent sized quality cast iron chunks but it's going to cost me a good bit. Guess I should have at least dragged one of those weights home and tried it out


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## Tin Falcon (Sep 18, 2010)

No worries peter one of the ways we gain experience is by making mistakes. The only way to avoid most mistakes is with experience. 
The item you need is often the one that just got disposed of two weeks ago. 
Tin


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## GWRdriver (Sep 18, 2010)

Ahhh . . . . Cast Iron. I know this flies in the face of the direction model engineering has been going for some time, and I know it's dusty and makes a mess, but good cast iron is my all-time favorite material. It always has been, it always will be. It does everything it's asked to do (turn, bore, mill, drill, tap, file, polish, etc) so well, and it's wot all the bigguns was made of. I'll accept whatever mess it might make in exchange for the pleasure of working it.


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## lowietje (Sep 18, 2010)

I took a old refer compressor apart and its a good source of high quality cast iron


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## Noggin (Nov 1, 2010)

Try this shameless plug www.nogginend.com


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## Blogwitch (Nov 1, 2010)

Noggin,

I just might have to make an appointment and come across to see you. You are not far away, as I only live just down the road in Crewe.

The main reason I don't like using metal suppliers is the carriage and the time it takes to get here. If you had a pick up service, then that would be something I would definitely consider a bonus. For the same cost in fuel, I could have the stock when I needed it, not after it has been half way around the country. If I posted a letter to my neighbour, it would be shipped out to Knutsford (about 25 miles away) to be sorted, then shipped back to be dropped thru their door, at the moment, anything up to a week.


Bogs


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## FIXIT (Nov 1, 2010)

Hi  looking at Nogin's (plug)  for brass bar i'm afraid you are a bit dear, Try cronus and its free shipping

Steve


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## Noggin (Nov 10, 2010)

Hey Bogstandard,

  We dont have a shop as such but you are more than welcome to give me ring and come over.

Hey Fixit,

  But are they as charming and delightful as we are


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## FIXIT (Nov 10, 2010)

No but you do seem to have a good range of matterial,
 and I've got you bookmarked


Steve


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## robwilk (Nov 10, 2010)

FIXIT  said:
			
		

> Hi  looking at Nogin's (plug)  for brass bar i'm afraid you are a bit dear, Try cronus and its free shipping
> 
> Steve





			
				Noggin  said:
			
		

> Hey Fixit,
> 
> But are they as charming and delightful as we are



Noggin just bookmarked you my self
How about a bit of discount for HMEM members  ;D :big:

Thanks for the link i think i might be placing a order soon.

Rob.......


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## Noggin (Nov 16, 2010)

Discount, you want a discount, why would anyone want a discount? O go on then you twisted my arm ;D

My poor mistress will have to miss a shopping trip.


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## Peter. (Nov 16, 2010)

Score!

I just picked up four cast iron sash-weights today, that look like really nice castings with clearly defined lettering. I'll take a pic of them later and stick them through the bandsaw see what wins


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## Tin Falcon (Nov 16, 2010)

I have scored the outer skin of weights with a abrasive disk maybe 1/16 deep then put on the edge of and anvil and give a good wack with a hammer breaks right through.
Tin


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## Peter. (Dec 5, 2010)

Lopped one end off one of my sash weights in the bandsaw. It cut slowly and smoothly and the quality looks just as good as any other piece of cast iron I've cut. I'll turn some in the lathe soon to see how it machines.


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## jpeter (Dec 5, 2010)

Some of you guys sound just like my students. They'd willingly waste my $40 band saw blade to save a dollar on a piece of steel. I had a rule about using the schools cutting tools on scrap steel. But, when I wasn't around they'd, janitors too, use my band saw to cut off rusty fence posts. Upon my return I'd ask why the blade had no teeth only to hear someone reply, "it must have been a cheap blade." I can't for the life of me understand why anyone would risk a carbide tool cutting down cast iron sash weights to save $2.00 on a piece.

 I'd suggest going to the metal house, spending a few bucks on quality, certified, material and finishing with a quality project and cutting tools that still work.


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## Peter. (Dec 8, 2010)

My bandsaw blades are only £7 a pop and I'm still on the first from a packet of 5 (and cutting this sash weight doesn't seem to have affected it's cutting capabilities). I don't see anything wrong with scrounging material for my home projects, if anything is unsuitable for machining it gets tossed into the scrap.


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## Blogwitch (Dec 8, 2010)

jpeter,

I have been using sash weights for my cast iron for many years, and haven't blunted a bandsaw blade yet with them. Mainly because I don't use a bandsaw for cutting it up. An angle grinder to just score thru the skin, then persuade it to break with a lump hammer, or just dropping it on the floor has the same effect (concrete, not carpet). Then a quickie 'under the skin' cut to remove the hard outer shell. No broken blades or cutting tools.



> to save a dollar on a piece of steel



It is a little more than that. I can obtain from one 35 pence sash weight, a good piece of useable cast iron, normally around 13" long x 1.375" OD, which, if obtained from a metal factor, about 15 pounds. I wouldn't call that saving a dollar, more like using your brain.

The quality does vary, depending where you come from. Here in the UK, we seem to have much better quality castings than from what people have said about US castings.

After removing 3" to 4" off the casting, opposite end from the hanging loop, all the dross and crap has been removed, and except for the loop itself, everything is then useable.

It machines and cuts just like any other close grained cast iron, and has been used for almost all the cylinders, engine blocks, pistons etc for the small engines I have made for many years, and I have never come across any problems. In fact, because they are usually over 100 years old, they have 'weathered', and the grain is exceptionally fine, and can be polished to an almost chrome like finish.

I am not boasting now, but the only time I purchase materials is when a customer requires a certain specification, otherwise I use whatever comes from the junk pile for making these little engines, or even tooling. Once you have gained experience in machining materials, you should be able to cut most materials with no or only normal deterioration of your tooling. If ever I break a bit of tooling, say a carbide tip, it is invariably machinist error, by being too eager to get the job done, taking a 0.250" cut rather than a 0.125" cut.

We are not in the 'full sized' world when we make these tiny miracles, so as long as you make the parts out of 'compatible pairs', then really, there are no reasons to go for exotic materials. Cranks and camshafts, for the amount of use they will get in their lifetime, can just as easily be made from free cutting mild steel, then a bit of case hardening afterwards, but only if needed. Only in a very high speed and/or highly stressed engine would I consider using some of the metals that some people seem to crave for, even when making the most mundane little engines.

It all boils down to experience. You get a sort of 'feeling' that what you are using is just fine for the job you are doing, and that has never let me down for many, many years, even when working for a living.


Bogs


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## Cedge (Dec 8, 2010)

I can vouch for the low quality of sash weights from the US. I just junked about 150 pounds of them due to air pockets, extreme hard spots and generally bad grain. Apparently they were made from cleared slag or the cold dregs from other pours. Carbide would hardly touch some of the hard spots and once it did, *POOF* there was another open void. I finally got my hands on some continuous cast Durabar and never looked back.

Steve


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## el gringo (Dec 8, 2010)

I've been getting my class 40 cast iron from Speedy 
metals, nice centrifugally cast for my Cly sleeves and piston rings. my last order (for the Silver Bullet I am building) Was a low grade (grey iron?). I made sleeves out of it but will use the good stuff I have left from previous orders for the rings (read scrap box). 
FYI
Ray Monahan


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## jpeter (Dec 9, 2010)

Lathing is ok cuz I can sharpen the bit but milling, which I mostly do, is more risky because the tools are so expensive. Cold rolled steel is the worst. I can't count the times I've ruined a bit on a glob of hard crap in a bar of CRS.


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## tel (Dec 9, 2010)

Here in Oz the sash weights are more as the Bogmeister describes, I've used a good number of 'em over the years and only came across 1 (one) that was a bit crook. 

The flywheels for my current project (Kerzel H&M) were hogged out of a big old roller from a baker's dough rolling machine - now that is one tough bit of ci, but workable just the same.


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## compspecial (Dec 19, 2010)

I bought some large cast iron blocks from my local scrap merchant, not knowing what they were, it was much later a friend identified them as being from off-peak electric storage heaters. Good stuff but a lot of hard work to saw into manageable pieces for the four-jaw.
I too have tried sash weights, and found it best to grind them all over before trying to machine them.
             Stew


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## Peter. (Dec 24, 2010)

Just thought I'd follow this up with my findings today. I think I've pretty-much hit both ends of the scale with my freebie sash weights. I picked up two large and two smaller weights, the larger being approx 1.75" dia and 16" long. The larger two pictured here cut nicely with my bandsaw and when I put one on my mill for a trial it really did machine like a dream. The smaller pair had a far inferior finish, with cavities on the surface and a much less even profile, these were all but impossible to machine, taking the edge off my home-made carbide tipped cutter almost right away and giving an un-even shiny finish with much knocking and grumbling from my mill. Those two are going right in the scrap.

Looks like I've had a pretty good score with the larger weights I probably have enough material there to machine at least a dozen cylinders, I'm actually thinking of making a complete working engine from one sash weight, cylinder, crank, rod and piston, just to see if I can.


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