A new way to retro-fit a J head

[golash]

Hi

I just got my bridgeport and thought that it might be easier to make a X and Y axis table that can be placed on top of the mill table. I`m thinking I could use smaller less expensive ballscrews then the normal 1 inch screws that would normally be retro-fitted into the machine. I was thinking Nook 5/8 diameter ballcrews.
Does this sound like a viable idea or is the design a poor attempt at cncing a bridgeport. My thoughts on this design was I could use the mill as a manual mill with DRO`s since I could remove the table system. With a good table locking system you could even leave the table on and use the mill manually.
I have a lot of THK parts left over from my DIY router that I could recycle
into this project.

Barry

[mc-motorsports]

I would just suggest using ballscrews
http://www.icai-online.com/product.php?productid=17070
I have a set of those and they work great. I have another mill with a set of $2500 german made screws and don't notice a difference. Other than that, both machines are extremely repeatable, so for precision production, just make minor adjustments and go. Plus the Brigeport Series 1 is not the most ridgid machine and you'll have a lot of tool flex and spindle deflection to deal with on super precision jobs.

[Belding]

I made something similar. It just bolts down using BP t-slots.

Zac

[Sparky_NY]

Originally Posted by golash Hi I just got my bridgeport and thought that it might be easier to make a X and Y axis table that can be placed on top of the mill table. I`m thinking I could use smaller less expensive ballscrews then the normal 1 inch screws that would normally be retro-fitted into the machine. I was thinking Nook 5/8 diameter ballcrews. Does this sound like a viable idea or is the design a poor attempt at cncing a bridgeport. My thoughts on this design was I could use the mill as a manual mill with DRO`s since I could remove the table system. With a good table locking system you could even leave the table on and use the mill manually. I have a lot of THK parts left over from my DIY router that I could recycle into this project. Barry

I did exactly what you are talking about last fall. I used the extended base and extended table for a X1 mill that I bought from littlemachineshop. It worked pretty good but it didn't take long before I wanted more travel and a bigger table. I couldn't use my 6" kurt vise on the little one.

I went back and made motor mount brackets for NEMA34 steppers and 2:1 belt drives. I used the little cnc to do this. I bought a rockford ballscrew kit for the bridgeport for about $700 from McMaster carr. I used Gecko drives. I am very pleased with the outcome and wished I had retrofitted the bridgeport table in the first place. There is nothing like the extra weight of that table, its heavier ways etc. There is a night/day difference in how ridgid the setup is. I can now use my bridgeport vise, rotary table, collet blocks, angle plates etc. Oh yea, its far more precise in positioning also.