6" chuck for a mini lathe

[Brian H]

I have inquired with a few companies regarding an independent 4 jaw chuck for my lathe. I have a 4"- 3 and 4 jaw scroll chuck, but would like to get a slightly bigger one that's more flexible for a few up coming projects. I haven't been able to source a direct bolt on one.
Pretty much everything I have found needs an adapter plate. I'm looking for suggestions that fit in my limited budget.

 

[YYCHM]

https://littlemachineshop.com/products/product_view.php?ProductID=2038&category=

Note the comment "This chuck is too big to fit on a mini lathe".

I'm thinking you are stuck and will have to source or make an adapter plate.

What is your budget?

FYI - I got a 4J for my 7-12 and find it's a PITA to set up. Space is so tight that by the time you have the dial indicator set up there is no room to use the chuck key. Your lathe sounds a step bigger since you indicated it came with 4" chucks.

 

[PeterT]

Brian can you clarify what you mean by 'direct bolt on one'. For example is it a thread mount nose or D-pin or ...?

 

[historicalarms]

Some small lathes do have a "direct bolt to" backing plate that is an integral machined part of the headstock. 3 bolts hold the chucks to the machine.

I did source out a 5" 4-jaw for my mini-lathe that I also use on my rotary table (the reason you didn't get it with the lathe Craig...sooorry) from Busy Bee. I had to machine a purpose-fit backing plate for the lathe back-plate it was to go on. I used a piece of 3/4 thick alum. because it was on hand but think a piece of 1/2 would have had sufficient strength for that lathe. I bolted the slab of alum to the lathe and then cut the recesses to match the chuck that came off the lathe then flipped it (it should center on your lathe B.P. perfectly now) and then cut the outside so the chuck fit centered and then drilled the chuck securing bolts.

The same alum B.P. was just drilled differently to bolt to my rotary table. I have a spud that fits the MT hole of the R T with a "machined to fit the I.D. of the chuck " spud on the other end. Centers onto the rotary table instantly.

 

[PeterT]

Gotcha. FWIW I bought a smaller 4J independant Gator for my RT & smaller parts holding in lathe. Its decent quality. The dimensions are the same as Bison & you can find different jaw configurations. I'm sure there are comparable chucks out there. If I understand your mount system correctly, you probably will requires some sort of intermediate plate or adapter with a matching lip. Most 4J's can be had with front mount bolts (because there is no scroll to conflict with) so it lends itself to both lathe & RT / fixture plate setup.

 

[Brian H]

https://littlemachineshop.com/products/product_view.php?ProductID=2038&category=

Note the comment "This chuck is too big to fit on a mini lathe".

I'm thinking you are stuck and will have to source or make an adapter plate.

What is your budget?

FYI - I got a 4J for my 7-12 and find it's a PITA to set up. Space is so tight that by the time you have the dial indicator set up there is no room to use the chuck key. Your lathe sounds a step bigger since you indicated it came with 4" chucks.

I was trying to keep it around the $100 mark. I think that i might be a little too hopeful. I have sent the dimensions to a couple of companies bit have not recieved any quotes. Since space is a bit limited on the 8x16 I wanted to try get something that booted in the three bolt pattern but an adapter plate may be the route I have to go

 

[YYCHM]

Have you pulled the chuck off your lathe yet? I'm betting your spindle plate has a 3 and 4 bolt pattern.

Sadly.... $100 is wishful thinking unless you source a used chuck.

 

[Brian H]

Yes, it has both. It appears to be a standard size. There are quite a few options for a Chinesium one. I was hoping for something a bit higher quality. I guess Ill just have to keep saving some more pennies...