Need Help!- Can I use a Super X3 Mill with a boring head externally on a ballscrew end?

[Plugger]

Hi,

I think I want to buy a Super X3 Mill. The main reason is because I don't want to get anything much heavier right now. It's about 365 lbs.

In any case, does anybody know if I can use a Super X3 Mill with a boring head externally on a ballscrew end? Somehow, I will make sure the end part of the ballscrew will be unheat treated. The head rotates 90 degrees and I assume it will be a pain to line up. I have three steel ballscrews to turn down and then I plan to use a die on them. Two are 1in dia x 53in long, the other is 3/4in dia x 41in long. On the ends of these, there is a section that is already turned down a little. I need to take a 1/2in length and bring it down just a little more then use a die on it. Also, is there a way I can attach the die/handle to the mill's chuck? I see a picture here at the very bottom of the page: Making a Screw Thread
but I can't see how they do it. The chuck on the Super X3 Mill should only be able to hold a 1in diameter. So, the die will probably be larger then the chuck's opening. Can I do this? I think I need the chuck/mill to start the die squarly unless there is some other way.

Thanks for any help! I'm kind of stuck.

[neilw20]

I'm not sure I really understand. Got a drawing?
It sounds like you need a lathe, or pay someone to do a one off job.

Nice excuse to buy an SX3. I like mine, used within it's limits is great.
Really sounds like you want to do thread milling, on it's side.

[Plugger]

Yes, I agree.... This is really a lathe job, but I don't need a lathe! I do need a mill for R&D and also to build a cnc router! I will have use for a boring head, so I was looking for tips from someone who has used one -- especially externally. The ballscrew shaft will lay horizontally, off the table and clamped in V-blocks spaced apart. If it is stiff enough, I think it should work. I am looking for thoughts on how to avoid the major pitfalls with this set up and job.

Now I just need to find something like a tailstock die holder for the Super X3's chuck or alternatively, a die holder with an R8 collet. (It's a big die since the thread is M20x1.)

Thanks!!




Thanks!!

[neilw20]

Machine cut the thread, either by thread milling then just run the die, by hand on the almost finished threads.
ISCAR Cutting Tools - Metal Working Tools - Iscar Catalog : MTEC E-ISO
Leave about 0.1mm to cleanup with the die. It will stay true, or if it doesn't I defy you to measure the error.
The SX3 can do this perfectly, but you will need to support the over hanging shaft as this will cause errors tilting the table.
It is not designed to have overhanging loads.
A small steel cable hanging from the roof (as long as it high enough) will support the end adequately. The X travel while machining will be quite short, so the error at the cable support will be minimal.
Considering what you will pay for the SX3, the small $'s for the cutter is of no consequence.
It will be a small challenge setting the head at exactly 90º, but the angular error will only affect the thread form slightly.

[Plugger]

Hi neilw20,

Thanks for your help!

The Super X3 will not have cnc capability. So, I don't think I will be able to thread mill it. I have never done any thread milling and I am not 100% sure I understand you correctly, but I did watch some online videos of it.

In short, I want to turn down the OD of a solid cylinder a small amount, thread that OD and then put a M20 x 1 nut on it. The nut will hold the bearing race so I want it to be square.

I think I found a holder for the die to make it square:

Amazon.com: Extra-Large Die Holder For 1 1/2" Threaded Dies: Industrial & Scientific

Amazon.com: Extra-Large Die Holder For 1 1/2" Threaded Dies: Industrial & Scientific

While I have you here, what's the max thickness 6061-T6 Aluminum you think I can practically mill with the Super X3? 1in? 1-1/2in?

ps - Thanks for the tip about the table not working well with a cantelevered load and using a wire from the ceiling!!

[neilw20]

While I have you here, what's the max thickness 6061-T6 Aluminum you think I can practically mill with the Super X3? 1in? 1-1/2in?

Well, it really depends on the size of the cutter.
Even with a 10mm cutter the cutter flex means you need to do a fine spring pass to finish.

Without CNC control to accurately control the feed you won't do it very well.
And machine stiffness and rigidity is very important.
My machine column is attached to a brick wall, and I lower weights under CNC control onto the head to achieve repeatability to 0.0001".
SX3 Vertical compensation :: Precision Z control video by neilw20_2008 - Photobucket
and you can't do that by hand.
Even placing weight on by hand gives irregular results. And that is with a 10mm cutter.
I also use 0.2mm drills, (they are invisible at my age)
http://i399.photobucket.com/albums/p...mallDrills.jpg

[Plugger]

Hey!! That's a pretty awesome setup!! Good job!

[Plugger]

Problem solved...

I'm just going to go with the next diameter size up in ballscrews. That way I don't have to machine one end. I was planning this so I could put a support with back-to-back angular contact on both ends. The column buckling load would be much greater that way.

Thanks for the help!