piston ring materials

[willynfo]

My brother has been trying to find a supplier of Meehanite cast iron for piston rings. he lives in niagara falls, ontario. all the cast iron he has used so far scores the cylinders and gives off a black oil. the engines smokes because the rings don't seat well. can anyone tell me where it can be purchased. the pistons are 1.25 to 1.5 in diameter. thanks for nay help. and no window weighs don't work well lol

 

[gerritv]

You can try contacting the authorised foundry in Quebec? http://meehanitemetal.com/our-foundries/

Gerrit

 

[goldstar31]

Surely there is more than one source of centrifugally cast Meehanite.

My source was/is a rusty marking out table which cost me all of £3.
However, failing a supply there should be things like brake drums or perhaps an engine block.
I agree that many sash weights leave a lot to be desired

Norman

 

[Mechanicboy]

You will find cast iron in old cam shaft (between the cams since the cams is hard to work with tool) or old brake disc. I has used the cast iron from brake disc as piston ring, last very well.

 

[dsage]

Try Terra Nova in Mississauga. All our club members do.
Meehanite is a brand name but they'll know what your talking about if you quote the name. I've used their continuous cast (grey cast) or whatever they choose to call it for all my rings and have had no problems.

http://www.terranovasteel.ca/Lang_ENG/

They don't normally deal with hobbyists and they appreciate you ordering it ahead so they don't have to scramble when you just walk in, but they will deal with you. I've always just bought whatever chunk they had laying in their cutoffs so as not to be a bother. It's cheap enough.

Sage

http://davesage.ca/

 

[lohring]

I got the very small amount of ductile cast iron I needed from McMaster-Carr. While I'm just starting to make rings, the machining process seems to go very well. The usual recommendation is Meehanite, but so far ductle iron seems fine.

Lohring Miller

 

[dsage]

Like I said Meehanite is a trade name and might just be their term for ductile cast iron. I don't know the specs for "Meehanite". (or any other cast iron for that matter).
Whatever I used from Terra Nova has worked fine for several engines. from .875 dia to 2-1/4 dia.
I don't think you can go too far wrong. Folks also use plain steel and bronze for rings. That's about as far as you can get from cast iron.
I'm glad you're finding it easy to machine.

BTW what method are you using to make your rings? (i.e "the Trimble method" or other)? As they say "The devil is in the details".

http://davesage.ca/

Sage

 

[///]

From the Meehanite website:
"Meehanite® metal is a family of different types of superior engineered cast irons, including nodular iron, flake graphite and white cast irons. The key to the undisputed success of Meehanite® metals is the rigid application of its patented manufacturing process."

Nodular is also known as Ductile and/or Spheroidal Graphite (3D iron in Australia)
Flake is also known as Grey or Gray iron, Continuously cast iron, Pearlitic Iron etc (4E in Australia)

Nodular/Ductile/SG/3D for compression rings
Flake/Grey for cylinders and oil rings

 

[petertha]

I got the very small amount of ductile cast iron I needed from McMaster-Carr. Lohring Miller

Good suggestion Lohring, but McMaster stopped shipping to common mortals in Canada many years ago. They only serve bigger companies & educational clients.

Speedy metals sells Class 40 grey which I think some builders have successfully used. Be aware they only ship UPS so you will incur the dinger fees into Canada.
http://www.speedymetals.com/c-8388-category.aspx

There are CDN Durabar dealers but I have yet to find one that will sell something less than the proverbial 10 foot pole.

Ive seen the odd ebay droppings but not often. If you discover any 'hobbysist volume' dealers, please post contact info, I'm interested too. (Those salvage suggestions were good, never thought of that).

 

[gerritv]

There is http://hobbymetalskits.com in US. They have Class 40 ci. For willynfo's brother that would work if he gets a US post box, eg. at http://cbiusa.com

There is also http://www.alro.com/divmetalsplus/ in Tonawanda, NY which has a retail location for cut-to-size.

 

[Brian Rupnow]

Barrie welding in Barrie, Ontario 705-726-1444 carries grey cast iron round bars in 1.5" and 2" diameter. That is where I buy most of my machining supplies.---Brian

 

[dsage]

McMaster Carr will ship to Canada (again). A couple of members have ordered from them recently. All you need is a company name on the bill. (nudge nudge grin grin). Pay all the taxes etc. No problems. And yes unfortunately they ship by UPS.

As mentioned before Terra Nova in Mississauga has lots of cast iron.
http://www.terranovasteel.ca/Lang_ENG/

Sage

 

[Walsheng]

McMaster sells "Easy To Machine Gray" and "Impact Resistant Ductile" cast iron.
Which would be preferred for IC rings?

John

 

[petertha]

McMaster Carr will ship to Canada (again). A couple of members have ordered from them recently. All you need is a company name on the bill. Sage

Well, you had me all excited there so I called them directly just now. According to the sales rep I spoke with, nothing has changed on their side in terms of policy in past many years. They require business or educational facility & account for Canada. So either your buddies got lucky or had the magic touch.

A few years back (our last attempt) we tried inputting business names which were legitimate & even had corresponding BN's &GST#. The ~ $100 order got as far as checkout & then the popup message saying no-go. We figured it must be electronically flagged by CDN based banking info, or web host, or whatever. Anyway, threw in the towel.

If you don't mind me asking, how much was the collective order?

I did order from about a year ago but it was through a US re-shipper. All legit, they copy/paste the invoice particulars for customs & charge a service fee to place order on your behalf of course. The good part is UPS in USA is cheap & then you can go USPS to Canada. The UPS direct to Canada admin dinger fees can be expensive, like 45$ to ship a box of duty free air.

 

[doc1955]

McMaster sells "Easy To Machine Gray" and "Impact Resistant Ductile" cast iron.
Which would be preferred for IC rings?

John

You want to use nodular cast or ductile, not gray for piston rings.

 

[Walsheng]

You want to use nodular cast or ductile, not gray for piston rings.

Thank you, I have a hunk of that.
What about for a cylinder?

John

 

[dsage]

petertha:

I guess they got lucky then. They were separate orders at different times. One guy placed his order because the other said he was successful.
I think one of them just ordered some special threaded rod in three foot lengths (or something). Not hundreds of dollars worth in either case.
As I mentioned they both used business names (which was required). So I'm not sure why they were successful. Depends on who handles the order maybe?. Bummer. I too was hopeful. I'll have to inquire some more.

doc1955:
A very simple answer. Can you elaborate as to WHY (nodular or ductile and not grey cast ?).


Sage

 

[gbritnell]

http://www.iron-foundry.com/grey-ductile-iron.html

 

[doc1955]

petertha:
doc1955:
A very simple answer. Can you elaborate as to WHY (nodular or ductile and not grey cast ?).
Sage

Nodular the molecules are spherical the grey is like flakes. Nodular is stronger or tougher and more forgiving and doesn't crack or break as easy.

 

[dsage]

George:
Thanks for the link. But after reading it my opinion would be that grey cast would be better for piston rings and cylinders. Since it is described as being more wear resistant and easier to machine. I don't think rings and cylinders require high tensile strength (as per ductile cast) as much as high wear resistance.
Now, I guess it could be that the nodular or ductile cast iron might also be just as wear resistant but it wasn't stated as it's prime attribute. My guess is it probably makes little difference which you use in a model.


Sage