View Single Post
  #1   Report Post  
Posted to rec.crafts.metalworking
[email protected] stans4@prolynx.com is offline
external usenet poster
 
Posts: 954
Default Tin Coating on old meat grinders

On Apr 19, 11:54*pm, "Ed Huntress" wrote:
"John" wrote in message

...





Ed Huntress wrote:
*wrote in message
...


Those old cast iron kitchen hand-cranked grinders, sausage stuffers, etc
are all silver. I have some that the coating is in pretty sorry shape&
they need a re-coat.


Am I correct in assuming it is tin?


Yes.


How is it applied? Are they "tinned" as in dipping or coating in molten
tin or simply plated?


The old stuff was hot-dipped, like hot-dip galvanizing.


It's not easy to replicate but you can probably do a good job with a
torch
equipped for metal spraying. Good luck if you try to melt it on like
solder.


Or just live with it. I have two grinders, one over 60 years old and with
a
number of worn spots. I just wash and dry it good and give it a light
wipe
with medicinal mineral oil.


I have seen mixing bowls *re tinned with a torch,a bar of tin and a wet
rag. *The bowl would be heated and the tin melted onto the bowl surface.
The wet rag would be used to spread the tin over the surface evenly.


John


Cast iron is tough to coat, John. Copper or steel are a lot easier.

To do a good job with cast iron you need an etch and the right flux.

--
Ed Huntress- Hide quoted text -

- Show quoted text -


In some old text I've got somewhere, it had how to do it for cast
iron. You've got to etch the stuff to get the graphite pockets
cleaned out, then use a pretty active flux to get the tin to stick.
Presumbably, the graphite surface pockets are still cleaned out on
used equipment, all that needs to be done is get the thing fluxed well
and re-tin. For repairing milk cans, it was more like tinning for
soldering, using a big soldering copper. Tinning cast iron was a
dipping process with flux floating on the molten tin bath. So for a
fairly large item, you've got to have a pretty big bath and a LOT of
tin. Not sure how well sandblasting would work for surface cleaning,
you want to have new media and not recycle it. I've done some sweat
soldering with small cast iron pieces, not easy even with acid flux.

Stan