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Bill Gruby
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Nice work Steve. Looks like you are not going to run into any trouble at all'
"Billy G"
"Billy G"
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9x20 Lathe CNC conversion
- Thread starter jumps4
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That's a nice motor mount you've carved out there! :thumbzup:
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- Apr 30, 2012
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this morning i have been going through my scrap bin and parts left from other builds to see what i have left for the z axis on the lathe. on the motor end i'll need a plate to mount the motor bracket and leadscrew support bearing to the lathe bed ( not really a bearing just something to stop whip ) . in the middle under the saddle i need a bracket to mount the leadscrew nut to and at the tail end of the lathe i need a thrust bearing mounted in a loose fitting bearing to the shaft. so i layed out the materials i have and what i think i am going to do.
the z axis should not be ridgid as far as in and out or up and down because the nut is tight to the shaft for backlash and any motion in the screw would be transmitted to the tool by raising the saddle up and down in and out so the bearings on the end are a loose fit except for the thrust bearing to maintain backlash. the screw i'm using is from my zx45 mill x axis, it is 1" 10 tpi and should last a long time and the nut is adjustable. it is not really hard so machining it hopefully wont be a problem. as least i wont have to grind it like a ballscrew. the 10 pitch of this screw should give me some pretty good rapid speeds if i have enough torque left in the motor for higher speeds the cutting torgue with the 880 oz/in motor should be pretty good also.
steve
the z axis should not be ridgid as far as in and out or up and down because the nut is tight to the shaft for backlash and any motion in the screw would be transmitted to the tool by raising the saddle up and down in and out so the bearings on the end are a loose fit except for the thrust bearing to maintain backlash. the screw i'm using is from my zx45 mill x axis, it is 1" 10 tpi and should last a long time and the nut is adjustable. it is not really hard so machining it hopefully wont be a problem. as least i wont have to grind it like a ballscrew. the 10 pitch of this screw should give me some pretty good rapid speeds if i have enough torque left in the motor for higher speeds the cutting torgue with the 880 oz/in motor should be pretty good also.
steve
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- Apr 30, 2012
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there are two main measurements i have to be careful to keep as close as possible on each end of the lathe. the height of the center of the screw on both ends below the saddle and the distance out from the bed to the center of the screw. any misalignment here will cause binding. and motion transmitted into the tool as the screw turns.
steve
steve
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Bill Gruby
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I am in awe Steve. You have come so far in just 6 days. You da man.
"Billy G" :+1:
"Billy G" :+1:
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i'm not as smart or as well organized as it may seem.
this was planned at the same time as the mill so everything was ordered at the same time and when i went to the scrap yard i had both in mind
while looking for materials cheap. I sat here broke for years studying other builds and dreaming all this up waiting for the day i could start already knowing exactly how it should be done in my mind. this 9x20 is a go between and that is why i'm being so cheap my next cnc lathe will be a lot heavier. so keeping in mind the limitations of the 9x20 and its capabilities but not wanting to buy more motors and controllers for a larger lathe i'm over powering these axis's for future use when a big lathe becomes available at a low price. i had to force myself from buying a 12x36 enco the other day for $700.00 because i knew i would stop on the 9x20.
steve
this was planned at the same time as the mill so everything was ordered at the same time and when i went to the scrap yard i had both in mind
while looking for materials cheap. I sat here broke for years studying other builds and dreaming all this up waiting for the day i could start already knowing exactly how it should be done in my mind. this 9x20 is a go between and that is why i'm being so cheap my next cnc lathe will be a lot heavier. so keeping in mind the limitations of the 9x20 and its capabilities but not wanting to buy more motors and controllers for a larger lathe i'm over powering these axis's for future use when a big lathe becomes available at a low price. i had to force myself from buying a 12x36 enco the other day for $700.00 because i knew i would stop on the 9x20.
steve
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Bill Gruby
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I cleaned the board for you. I have a question however. Would it not be better to swap the leadscrews involved in favor of Ballscrews?
"Billy G"
"Billy G"
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yes it would be a lot better to use ball screws it takes less torque to drive them so i could run them faster.
but this is a go between thats why i'm not doing anything i cant reverse to make it manual again and i'm saving the money for ballscrews for a bigger lathe build maybe something like my new 11x26 it is really ridgid and cheap new $1600.
then when i find a bigger lathe cheap all i have to buy is the ballscrews and bearings. and if i put them on this build they would be too short for a bigger lathe.
I took a break on this today to finish the mills 4th axis
steve
but this is a go between thats why i'm not doing anything i cant reverse to make it manual again and i'm saving the money for ballscrews for a bigger lathe build maybe something like my new 11x26 it is really ridgid and cheap new $1600.
then when i find a bigger lathe cheap all i have to buy is the ballscrews and bearings. and if i put them on this build they would be too short for a bigger lathe.
I took a break on this today to finish the mills 4th axis
steve
