Clausing 8520 TouchDRO

I'm adding digital readouts to a 1968 Clausing 8520 milling machine.

[@douglassmith2055]

Nice little gem of American cast iron

[@bryanrj50]

I have the 8530 version, and am wanting to add a DRO. I like the Bluetooth idea. Subscribed.

[@thesergeant3524]

Nice machine! I'd love to see a detailed video on how you went about installing the DRO on your mill and why you chose the scales you did. I'm finishing up an early 8520 rebuild myself and am thinking about adding a DRO and possibly a VFD as well.

[@jonrbryan]

I've got a thread going at hobby-machinist.com/threads/clausing-8520-touchdro.62653/ that shows more details. I'm planning to do another video to post here, and post more pictures over there as the rest of it comes together. I'm using Shars aluminum scales because the accuracy of the aluminum scales is pretty much indistinguishable from the stainless ones, and they are MUCH easier to work with. The stainless scales are so hard you have to use carbide drills. Even good cobalt drills won't touch the stuff. Oh, and the aluminum scales were on sale direct from Shars. Other types of scales, like optical and magnetic, are available with higher resolution, but I think the Shahe/Shars/iGaging capacitive ones are a good match with the inherent precision of the machines that I have. The man I bought the mill from was selling a Hardinge HLV lathe (and was the original owner). I would not put this kind of scale on a machine like that, which is capable of doing sub-tenth work. I really like the VFD's that I have on the mill and drill press. It just takes some time to figure out how to set them up properly. I showed one reason that I went with the Fuji in the video. It supports an external braking resistor, where the Teco on my drill press doesn't. Plus, it's TINY. I only went with a 1/2hp motor on the mill. I went for 1hp on my drill press to get some more torque at low RPM's, and the Teco is twice the size. I programmed the mill for a much narrower speed range and will still use the pulleys for gross speed changes. I would do the same thing if I ever put a VFD on my lathe, and set it up to stop the chuck in a hurry. That requires using an external resistor to dump the energy into.

[@minskmade]

great video john. i really need to find one of these mills.

[@mibooth1852]

Any updates on this great machine ?

[@outoftheirskulls5676]

M. Sheen Machine Inc.

[@gordon6029]

I would love one of these milling machines. They are rare but nonexistent where I live. There is one about 3000 miles away but I can’t buy it unseen and shipping might hurt.

[@jonrbryan]

I got lucky and picked mine up from a retiring machinist. He had it set up to do finer work because it would hold closer tolerances than his Bridgeport clone (that I was actually there to look at). It's a good, solid machine if you can live with its limitations.

[@petera1033]

I am interested in joining the 21st century and teaching myself in order to get up to speed with such interesting technologies ( now affordable) for the home enthusiast - good luck with your you tube channel and I look forward to seeing more of what you have to say. I will certainly follow teh link you provided below to hobby machinist. PS a pity I missed out on being one of your first dozen subscribers -:) All the best Pete ( Sydney Australia)

[@jonrbryan]

Thanks, Pete. I still need to do some cable management and a cover for the Z axis scale, but the VFD and TouchDRO board are properly enclosed and mounted now. I'm going to try to make another video this weekend. Then I'm thinking of starting work on an electronic lead screw for my Logan lathe. I think it's the perfect machine for it, with no quick-change gearbox to get in the way. Turning a knob to set the feed rate or thread pitch would be pretty luxurious, and making metric threading easy would be a pretty nice bonus, don't you think?

[@petera1033]

Hi Jon. I think that you would generate enormous interest in putting together a series documenting the ELS conversion of your lathe. I am in the process of getting Paul Babin to rebuild a Hardinge HLV with his ELS system for exactly the same reason. FYI - a company in Germany has just released an ELS system which is very economical unfortunately the instructions are only in German and the company at this stage, the web site is worth looking at "www.rocketronics.de" and the contact person is :"Louis Schreyer " As for metric - once you go there there is no going back to fractions and all the associated shenanigans -:) Cheers Pete

[@jonrbryan]

The components are coming together. I'm going to prototype with a closed-loop stepper driving the leadscrew since I can buy one of those for $100. If all the groaning from the stepper gets to be too much I figure I can switch it over to a ClearPath servo and have a drop-in replacement. I'm going to use a 5:1 ratio timing belt that should help with the groaning, but those pieces haven't arrived yet. I'm afraid that I will also have to use a timing belt to connect an encoder to the spur gear in order to fit it under the cover. I intend to work on hooking up an encoder to an Arduino this weekend and get quadrature decoding worked out. When I was in Robotics I always did it in hardware, and I'm concerned that an Arduino can keep up and have time left to do anything else. I've got a 2.8" color touch screen LCD running on my Arduino Uno, but I've got a feeling that it has taken up all the pins I need and I'll have to switch to a simpler display or a bigger MCU, so I have a Mega ordered. Anyway, thanks for the encouragement!

[@blackoakmushrooms]

Holy SHit you look like Martin Sheen Man!

[@garyhoffmann1615]

Martin Sheen might be his love child.

[@Actually_Miralles]

Do you have a video or schematic on wiring the external pot and start/ E-stop (braking resistor?) I have the same setup with a Fujitsu VFD

[@jonrbryan]

I didn't wire a remote pot, I use the one on the VFD. The braking resistor connection is really straightforward. You won't have any trouble figuring it out.

[@mrx.2233]

Your audio is very soft. Need to work on that

[@mibooth1852]

Jon , where did you get your keyless drill chuck is it MT2 3/8" 16 ?

[@jonrbryan]

It's a Grizzly 5/8 with a JT3 taper. I believe the JT3 to MT2 arbor was also from them, but it's been too many years. It's been a good chuck.

[@mibooth1852]

@@jonrbryan Thank you for the info sir.

[@qzwqsy]

What motor setup did you go with? I was to update my 8520.

[@jonrbryan]

I'm using a 1/2hp Hallmark Industries MA0505E 3-phase motor from Amazon that I'm driving with a Fuji Frenic-Mini FRN0003C2S-6U VFD from Wolf Automation. I put the VFD and braking resistor in a proper enclosure after this video was made. It's worked great for everything that I've done with it so far, and I haven't felt any need for more horsepower.

[@qzwqsy]

Thank you very much for the information.

[@qzwqsy]

Hoping you do more videos on your 8520.