ShopTask Ballscrew Install

[Sprint 77]

I got my Rex industries Ballscrew in last night will be giving some phot shots soon of before during install.

I do stand corrected though the "Y" axis will need the gear to gear reverse direction for the handle not the one I have the 3-D Solidworks model of in other posts.

I feel like these ballscrews will be as good if not better than the Nook screws that are sold for the Shopmaster Shoptask.

I also got my toolpost grinder attachment in ( thanks www.littlemachineshop.com ) so I can fit the screws to the machine .

[instructor37]

I got my Rex industries Ballscrew in last night will be giving some phot shots soon of before during install.

I do stand corrected though the "Y" axis will need the gear to gear reverse direction for the handle not the one I have the 3-D Solidworks model of in other posts.

I feel like these ballscrews will be as good if not better than the Nook screws that are sold for the Shopmaster Shoptask.

I also got my toolpost grinder attachment in ( thanks www.littlemachineshop.com ) so I can fit the screws to the machine .

I would suggest that you use a 2/1 reduction on your gears to keep the dial calibration the same, since the ballscrews are usually 5TPI as oppossed to the standard 10TPI acme screws. It will also reduce the handle effort, since you will be back spinning your stepper motors. If you have DRO, you will be fine, but with normal backlash in any type of straight cut gear, maintaining accuracy with the dials will be a challenge.

[Sprint 77]

I would suggest that you use a 2/1 reduction on your gears to keep the dial calibration the same, since the ballscrews are usually 5TPI as oppossed to the standard 10TPI acme screws. It will also reduce the handle effort, since you will be back spinning your stepper motors. If you have DRO, you will be fine, but with normal backlash in any type of straight cut gear, maintaining accuracy with the dials will be a challenge.

Very good input . Thanks I will keeep all that in mind I have not purchased my gear to gear reversing gears yet so I will look for two things a helical style for reduced backlash and an 2 - 1 reduction. I apreciate the input.

[dgapilot]

Sprint 77,
Did you make drawings of your ball screw/nuts? I've got a Bridgemill that " would like to eventually convert, but don't want to tear the machine apart to measure, then reassemble to cut the screws, and tear it down again to install. If I had drawings so I could cut the screws and make mounts for the nuts, that would make it easy.

[Sprint 77]

Sprint 77,
Did you make drawings of your ball screw/nuts? I've got a Bridgemill that " would like to eventually convert, but don't want to tear the machine apart to measure, then reassemble to cut the screws, and tear it down again to install. If I had drawings so I could cut the screws and make mounts for the nuts, that would make it easy.

I do have mine apart and have the parts modeled in Solidworks 2010 , however I have extended my axis by 6 inches over stock and if you did not use the same brand nallscrew as I did these dimensions would not help you. There is no ballscrew " industry standard " mounting.
I am also not seeing you cut the new ballscrews on your machine. most ballscrews are hardened and need to be ground not cut.
I hope this enlightens you to find a solution for your conversion.

After I get mine working under CNC power I might offer the "KIT" for my mods. I got to prove it out first.

[instructor37]

I do have mine apart and have the parts modeled in Solidworks 2010 , however I have extended my axis by 6 inches over stock and if you did not use the same brand nallscrew as I did these dimensions would not help you. There is no ballscrew " industry standard " mounting.
I am also not seeing you cut the new ballscrews on your machine. most ballscrews are hardened and need to be ground not cut.
I hope this enlightens you to find a solution for your conversion.

After I get mine working under CNC power I might offer the "KIT" for my mods. I got to prove it out first.

Any new info? Would like to see some pics if you have them.
Thanks

[GunPilot]

After I get mine working under CNC power I might offer the "KIT" for my mods. I got to prove it out first.

I'd be interested in such a kit...

[Injuhneer]

I have an Eldorado Bridgemill as well. I have purchased a set of SKF ball screws to install but am wondering if anyone has taken the dimensions for the OEM ACME screws? I only have one machine and if I can avoid disassembling it to measure, reassembling to make the new screws, then disassemble to install, then install the new screws, I'd like to avoid those extra steps.

[Sprint 77]

I have an Eldorado Bridgemill as well. I have purchased a set of SKF ball screws to install but am wondering if anyone has taken the dimensions for the OEM ACME screws? I only have one machine and if I can avoid disassembling it to measure, reassembling to make the new screws, then disassemble to install, then install the new screws, I'd like to avoid those extra steps.

I have some dims of the Eldorado carraige on mine in solidworks.

You will more than likeley have to remove and install twice.

Also keep in mind that you will need a gear to gear reverse direction on the "Y" lead screw it is left hand from the factory, and as far as I know Nook is only one making left hand ball screws small enough for shopmaster.

[Injuhneer]

It should be the other way round (RH on Y, LH on X). The slide/table moves and the screw is affixed to it so the thread is RH. The carriage and its nut travel on the X so the thread is LH.

For CNC it is just a bit-flip to reverse the axis. The manual travel isn't a problem since the there is a reverse already in place. But your advice is well-taken because the dials and all the threading gears are set up for the 10tpi ACME; so a 2:1 reduction/reversing drive would make it behave as before with the 10tpi.