Ron Steele's Mini Lathe CNC Conversion Lead Screw

[tetralite]

I'm doing the CNC conversion as per Ron Steele's plans for the 7x10, 7x12 or 7x14 mini lathe. These plans specify a lead screw from McMaster.com (part #6350K15). This is a 3/8" diameter, 0.5" pitch, 4-start stainless (303) ball screw. When you buy it from McMaster.com you have to buy a 72" length minimum and it costs $123.14 plus shipping. So I bought one along with the matching wear compensating nut (part #6350K55) and since I am converting my single 7x12 lathe, the plans call for just a 20" length of the screw. The result is that I now have 52" of leftover, brand new ball screw stock. So if anyone else out there is doing a similar conversion and you don't want to buy extra lead screw stock I am willing to sell you all or part of my leftovers at the same price per inch that I paid ($1.71/inch) plus shipping (probably about $10 for shipping). This will save you from having to lay out over $125 for the screw. You can view the specs for this lead screw by entering the part number in the search on the McMaster.com website. Send me a message or respond to this post to contact me.

[tetralite]

Update: I now have just shy of 30 inches of lead screw left (actually about 29 & 15/16"). More than enough for the 7x14, 7x12 or 7x10 conversion.

[tetralite]

This is an update to my previous post. I still have a 30" piece of this leadscrew stock that I will sell for $50 (that's a little less than the price I paid for it) plus $10 for shipping. Send me a private message if you are interested.

Originally Posted by tetralite I'm doing the CNC conversion as per Ron Steele's plans for the 7x10, 7x12 or 7x14 mini lathe. These plans specify a lead screw from McMaster.com (part #6350K15). This is a 3/8" diameter, 0.5" pitch, 4-start stainless (303) ball screw. When you buy it from McMaster.com you have to buy a 72" length minimum and it costs $123.14 plus shipping. So I bought one along with the matching wear compensating nut (part #6350K55) and since I am converting my single 7x12 lathe, the plans call for just a 20" length of the screw. The result is that I now have 52" of leftover, brand new ball screw stock. So if anyone else out there is doing a similar conversion and you don't want to buy extra lead screw stock I am willing to sell you all or part of my leftovers at the same price per inch that I paid ($1.71/inch) plus shipping (probably about $10 for shipping). This will save you from having to lay out over $125 for the screw. You can view the specs for this lead screw by entering the part number in the search on the McMaster.com website. Send me a message or respond to this post to contact me.

[slick_rick]

I was curious how the conversion is going (went?). I'm considering trying the Steele plans myself but I'm looking for a writeup/review of the brave souls who have gone before me ;-)

[tetralite]

Originally Posted by slick_rick I was curious how the conversion is going (went?). I'm considering trying the Steele plans myself but I'm looking for a writeup/review of the brave souls who have gone before me ;-)

I finished the conversion some time ago and it went very well. I am quite happy with it. Steele's plans are excellent -- no info is left out and the drawings are great -- excellent dimensioning and no mysteries. Some of the aluminum parts that you have to make are thicker perhaps than necessary, but it is better than being under-built -- if this is over-built than it's not *that* over-built. It was worth the time spent. I used my Taig CNC mill to shape the parts that needed shaping and I used the lathe throughout the conversion for making some of the parts and even parts for other things, so the lathe was never out of commission for more than the time it took to actually install the conversion parts (minutes). Also, this conversion still allows you to manually operate the lathe which is very handy when you just need to rough something out in a hurry rather than going through the CNC setup for a simple part.

It is really cool watching it cut all by itself, especially threading. Cutting tapers and odd shapes is of course much easier with CNC. You can get really nice finishes on parts with because you're not limited to the auto-feed gear speeds of the lathe or cranking the cross slide by hand at uneven rates. I faced an aluminum part using a very slow cross feed and a fairly high spindle speed and it came out looking almost like a mirror finish. So I'm really happy with it.

[Tymawr]

Hi,
I about to convert my mini lathe to CNC, using Ron Steele`s plans. Have you any of the MCMaster #6350K15 lead screw left you could sell me ?

[tetralite]

Yes, I still have that 30" piece of leadscrew left for $50 plus shipping. I'll send you a private email to discuss it. It looks like you are in the UK so shipping would cost more than the $10 I mentioned in the previous post.

[davekeck]

Hi All,
I just purchased the plans from Ron Steele.

After seeing this thread I emailed him and asked him if he would sell me the length of rod I needed for my Mini-Lathe along with the plans. He said no problem. He charged $40 for a length that I need for the 14" Micro-Mark lathe. the current price at McMaster is $133 for 6 feet.

Dave

[tetralite]

I still have that last piece of ballscrew that is a bit longer than you need for the 7x12 or 7x14 lathe and I will still sell it for what I paid for it (by the inch for the whole 30" piece = $50). I see the price at McMaster has gone up a bit. Anyway, I still have this ballscrew if anyone wants to buy it for $50 + shipping ($10 to anywhere in the USA)!

[ianober]

Tetralite, did you use the proximity sensor for the spindle speed? I converted mine and am trying to get the sensor working with my Hobby CNC EZ board. I cannot seem to get Mach3 to see the signals for some reason.

[tetralite]

I used an optical interrupter as shown on my page at http://tetralite.com/lathe/spinsensor.html

Be certain you have an adequate signal level coming from whatever type sensor you use, then be sure to make all the required settings in Mach3 (check the Mach3 manual for details).

Also, you might want to look at my notes about the Mach3 settings on my page at: http://tetralite.com/lathe/

Although my set up uses different equipment than yours, much of the Mach3 settings should apply.