Changing lathe chucks

[csharp]

I have a HAAS SL30 with a 12" Samchully hydraulic chuck.

I want to change it over to a 4 jaw. We mainly manufacture split parts and must center the split line in the chuck before turning.

The back of the Samchully chuck does not have an A2-6 taper. It has a flat back and uses an adapter plate to connect to the A2-6 spindle nose.

The chuck I would like to use is a 10" 4 jaw with an A2-6 on the back. My question is can I bolt it directly to the spindle nose? There are ac couple of bolt patterns on there and some holes would not be filled. Would there be any chance of contamination of the spindle bearings? Is that plate on the back of the Samchully strictly an adapter or does it offer some sort of sealing of the extra holes?

I have already found the parameters to ignore chuck pressure and allow the hydraulic pump breaker to be opened so it does not run all the time.

Thank you.

 

[Mtndew]

If the chuck is A2-6 and your spindle is A2-6 then yes, bolt it direct.
The plate on the back of that Samchully is just an adapter.

 

[Nmbmxer]

Just a thought but if you're going to swap back and forth a flat back 4 jaw is likely a lot cheaper and you could put another set of holes in the adapter you already have. That would be one less set of bolts you'd have to remove to change over. Also any wear from change over would be on the tapped holes in the adapter vs the tapped holes on the spindle nose.

 

[csharp]

Thanks for the answers. I assumed it was fine but thought I wanted to be safe.

I understand what you are saying about a flat back chuck. However I already own the one I am installing and will likely never change it back. This kind of work makes up 95% of what I do so a 4 jaw is a must.

I used to chuck the 4 jaw in the 3 jaw but that is getting old.