Tapping cast iron

waynemn

Registered
Registered
Joined
Feb 17, 2016
Messages
4
I have a piece of steel I want to attach to cast iron frame on my lathe countershaft.

Which way would be better, bolt going through-hole on iron piece and tapping for the bolt on cast iron or through hole in the cast iron piece and tapping
the hole in the steel part?

waynemn
 
Cast iron is easy to drill and tap.. So to answer your question witch ever is best for the application.
 
It would depend on how thick the cast iron is; ideally, you'd want perhaps twice the diameter if the fastener in thickness of the iron; if the thickness is not sufficient, the fastener could strip out.
 
A lot would also depend on the "width" of the casting as well. And how much force it has to carry. All of this depends on the size of the bolt versus the width, thickness, et al.
The last few times I did this, I used the fat part of a strip of bacon as the lubricant. There are a lot of good fluids out there, most illegal. Bacon was cheap, disposable, and in no wise related to anything but cooking. It works good, too.
 
As in all things... it depends. In general, if everything is equal like thickness, overall size etc., threads in steel will be stronger than threads in cast iron because carbon steel is stronger than cast iron. Your question is too general without enough specifics to give a specific answer, but this is a guideline.

Ted
 
I guess the other option if you are unsure and since you can come through from either side...it sounds. Then just put in a clearance hole in both pieces and use a nut and bolt. But I may not be visualizing your arrangement.

David
 
I guess the other option if you are unsure and since you can come through from either side...it sounds. Then just put in a clearance hole in both pieces and use a nut and bolt. But I may not be visualizing your arrangement.

David
Hi David
Clearance hole in both pieces is a possibility. There is plenty of room.
waynemn
 
I would prefer to tap the hole in steel as it would be stronger and take a better load. also if you need to remove it and install it a lot I would do that better in steel bill
 
I would prefer to tap the hole in steel as it would be stronger and take a better load. also if you need to remove it and install it a lot I would do that better in steel bill
Thanks Bill
That was kind of my thought also, wanted to kind of confirm it. It would be a one time attachment and do not foresee a need to remove it.
waynemn
 
Back
Top