[jimluu]

Hi, I finally decided on my design, which will be 3x6ft. This is a great forum, but generated as much questions as answers. I need to find a reasonable way to drive my x-axis. I plan on running 2 leadscrews (one on each side). What diameter should I use? How many turns/inch? I really like the modified acme rods at mcmasters, but I have no way of finishing the ends for mounting. Is there another source that sells prepared leadscrews? Is a 260 oz motor/per side adequate? I mainly use it for cutting wood.

thanks a bunch. jim.

[lgalla]

Jim try Ebay stores for "precision-cnc-router"
Larry

[thkoutsidthebox]

I really like the modified acme rods at mcmasters, but I have no way of finishing the ends for mounting.

I have 2 start precision rods for my new machine, and was originally going to go with ballscrews simply because I couldn't get the leadscrew ends machined, and dont have the tools (ie: Metal cutting lathe) to do it myself, but I went with the leadscrews and have a plan to machine the ends using just my drill press and a grinding stone. It'll be in my build log when I get that far if your interested. There is always a way!! http://www.cnczone.com/forums/showthread.php?t=35211

[the__extreme]

I have 2 start precision rods for my new machine, and was originally going to go with ballscrews simply because I couldn't get the leadscrew ends machined, and dont have the tools (ie: Metal cutting lathe) to do it myself, but I went with the leadscrews and have a plan to machine the ends using just my drill press and a grinding stone. It'll be in my build log when I get that far if your interested. There is always a way!! http://www.cnczone.com/forums/showthread.php?t=35211

Haha! Drill press & grinding stone...I Love it!


As for the 6' leadscrew....that's a spicy meatball! I bet there would be some serious whip when that thing gets spinning! I wonder if you could get away with a long piece of all-thread if you put it under tension? For something that long, I wouldn't go any smaller than 1/2" diameter, but someone with other experiences should also comment.


- Shawn

[jimluu]

Thank you for the replies. I found an ebay seller who would sell me a pair of ballscrews for $125! see the link. Will this work for my x-axis? I have only tonight to finalize the deal. What else would I need to make this work? thanks.

http://cgi.ebay.com/ws/eBayISAPI.dll...5299&rd=1&rd=1

[rustamd]

What about using R&P?

[jimluu]

I've read that r&p have too much draw backs...not very efficient and not very accurate. This guy from ebay will sell 2 84" rod for $125. They are new, with some surface discoloration. I can't find leadscrew for any where near this price. Would someone look at the ad and see if I'm overlooking something? thanks. Looks like the ends are already prepped so my issue with having to machine the ends is solved.

[jimluu]

The ends are 3/4 one side and 1" the other. I guess I'll be using a nema34 stepper motor. Is there a coupler that can go from 1/2" to 1"? thanks.

[thkoutsidthebox]

So are you the Boom guy who won or the other guy who was out bid by $2 ?

Haha! Drill press & grinding stone...I Love it!
- Shawn

Thankyou....I think!

[jimluu]

So are you the Boom guy who won or the other guy who was out bid by $2 ?

Thankyou....I think!

Actually the seller have several more. He's selling $200 shipped for 2. What else to I need to make this work? Coupler of some sort?

[ahren]

Search for "lovejoy" coupler from McMaster, MSC, or Enco. These are basically a three piece coupler, and you can choose the opening in each piece. I'm pretty sure you can get a 1/2" to 3/4". Not sure about 1".

For those of you who want to use 1/2" leadscrews, I'm going to start selling a setup in a couple of weeks that lets you support the screw with thrust and radial bearings without having to do any machining on your screw. It will be priced for the hobby community. Combine it with a dumpster anti-backlash nut, and you'll be good to go. PM me if you're interested.

[thkoutsidthebox]

1" to 3/4" Jaw coupling.

I order from these and have found them very good. Also good prices.

http://www.surpluscenter.com/sort.as...Jaw%20Coupling

You want Item numbers:

1-1106 and 1-1108

And the insert for it is on page two:

http://www.surpluscenter.com/sort.as...07041604021954

Item number:

1-1110

Hope this helps.

[jimluu]

Thank you for the links. Great prices. I called around and everyone is asking for $600-$1k for a new ballscrew of the same dimension, so I went ahead and bought it. Hope it works out. Supposed to be brand new. If anyone know of a good source of support units (fixed and floating) for 1 inch diameter shaft, please let me know.

Will this fit the floating end?

http://www.vxb.com/page/bearings/PRO...arings/Kit7369

[lgalla]

Misumi USA
Support,under$1oo floating,under50bucks.
Larry

[jimluu]

My ball screws finally arrived today. Can't believe how large and heavy they are. There's a bit of rust....any good ideas on how to safely remove the rust?