PM-833TV CNC conversion kit availability?

[7milesup]

The premium Heavy Metal kit comes with ground ball screws and it's only $200 more than the standard one with rolled screws.

That is really interesting. They have to be sourcing the ground ball screws from China. I have priced out ground ball screws from here in the US and I thought they were around $1k each.

EDIT: I just looked at ground NSK from Automation Direct and they are about $1200 for just the X-axis.

 

[kirkrockwell]

Matt, that was my thought to. The 'not doing business' reply came in fast and might have been a leftover autoreply. I can wait until this time next week to see if they refund the amount, or if they hold onto it I'll expect some shipment info.

I see your point about making the mounts, pockets and bearing holes can be made manually. If the order falls through that can be my backup plan. At that time I might ask you for dimensions/pictures of the mounts, and ballscrew features, for whoever I get to turn them down and add threads.

I did request the premium ballscrews option for $200 more and have set modest expectations. Until I get the mechanical parts sorted out I'm holding off on buying servos or drivers etc...

 

[BehemothTheCat]

Kirk, in my case, nothing was being done to get this order taken care of until I filed a claim with PP. Jose got in touch with me literally 10 minutes later. This might have been a coincidence, but I find it unlikely. I don't get why he continues to ignore e-mails now that they brought the website back on. I'd understand if he were slow to reply given the circumstances, but this whole thing is just bizarre. Even if he doesn't want to deal with this again, it makes sense to move their existing inventory rather than let it become scrap.

My take on it was similar to yours. I didn't want to order the conversion kit until I had the mill and made sure it was in good order. Life and work keep interfering, so it will be a while before I put it together, but that's ok. I enjoy the process more than the outcome. I have a lathe (PM1340GT) on order with PM (paid in full), but have already accepted the possibility I may never receive it. After all, it's a Taiwanese lathe and by the time it's ready to ship, Taiwan may share the fate Heavy Metal CNC. Strange times we live in.

I will take pictures and measure the critical dimensions as I install parts. Don't expect Fusion360 models, but it should be enough to fabricate a replacement.

 

[kirkrockwell]

Kirk, in my case, nothing was being done to get this order taken care of until I filed a claim with PP. Jose got in touch with me literally 10 minutes later. This might have been a coincidence, but I find it unlikely. I don't get why he continues to ignore e-mails now that they brought the website back on. I'd understand if he were slow to reply given the circumstances, but this whole thing is just bizarre. Even if he doesn't want to deal with this again, it makes sense to move their existing inventory rather than let it become scrap.

My take on it was similar to yours. I didn't want to order the conversion kit until I had the mill and made sure it was in good order. Life and work keep interfering, so it will be a while before I put it together, but that's ok. I enjoy the process more than the outcome. I have a lathe (PM1340GT) on order with PM (paid in full), but have already accepted the possibility I may never receive it. After all, it's a Taiwanese lathe and by the time it's ready to ship, Taiwan may share the fate Heavy Metal CNC. Strange times we live in.

I will take pictures and measure the critical dimensions as I install parts. Don't expect Fusion360 models, but it should be enough to fabricate a replacement.

Gotcha, I'm thinking a week is long enough to see what kind of response HMCNC will give. I have a note on my calendar to start the refund process after that. Given that it's been a couple months since Bruce's passing, it may be that his estate and business are already tied up in probate court. Some states allow for the uninterrupted continuation of a small business after the owner passes, depends on the custom in Texas I suppose. Would like to think theres a kit sitting there on a shelf waiting for me though.

I bought a new house this month, still don't even have my trailer unpacked. And for some reason I'm worried about a mill that is going into a shop space that is third on the list to get built out, after my basement shop and my leather studio. I mean, the mill is supposed to show up on a truck tomorrow, that's the only reason it's in front of me to move on the CNC process. If I had a kit it would still be summer before it gets much attention...

No kidding! The first call I'm making after my phone line gets installed tommorrow is to PM to get a 1340GT on backorder . I guess the PM-833TV and 1340GT hits a sweet spot for a lot of us...

Thanks, pictures and dimensions would be a great assistance!

 

[chafey37]

And the hmcnc site is down again

 

[INTJ]

Any of you guys that have converted want to sell me your old X-Axis screw? Last Jan the movers tipped over my 833T and it hit on the X-Axis screw. Just got moved into my new house and am setting everything up, and finally have time to get to my Mill.

I need to X-Axis screw, a bearing, and some other misc parts. Probably the X-Axis nut as well.

 

[arizonavideo]

Hi Matt,
I am in that situation, purchased the PM-833TV with intentions to convert for CNC use. I ordered it in early January, and it is supposed to be delivered this Friday. I had several calls into Bruce's phone number, and didn't understand why I couldn't get a call back. I found out here about the bad news. I suppose they still have the kits in stock, and are hopefully re-grouping to keep going. But I also imagine the recovery will take time, nothing generates more grief and paperwork than an unexpected death...

I'm really hoping to salvage this project, do you have contact info for Jose, if it's ok to ask?

I have also contacted David at Arizona CNC Kits, asking if maybe one of his kits would crossover. He seems willing to work with me if I can get measurements to him for comparison. When it gets to my shop I'll see what I can find out. I don't have any experience with the other benchtop models so I don't have any clue what is the same or different between them. If anyone has the experience I'd welcome the help.

I got hooked on CNC when I worked for a shop that had a Tormach 1100 for production use. To train myself, I bought and converted one of the Sherline 5800 desktop units for CNC, using steppers, Gecko drivers, and Centroid Acorn. I learned Fusion 360 Design and Manufacturing modules and sucessfully made a lot of small parts. The PM-833TV really looked like a nice step-up option so I worked up a list of stuff to buy following the online example by Dr. D-Flo.

I'm sad to see Bruce pass and not be able to keep going in the kit businesses. I'm going to start next week on a new CNC kit for the PM-932 and the PM-833. The big question I have with the 833 is it's a more expensive mill and buyers expect more from it.

On the ball screws I have been using C7 grade rolled screws with double nuts that I re work to be nice and tight with positive preload. This give really good backlash but they are still a rolled screw so accuracy over distance will only be so good.
Going to a ground screw will yield better accuracy over distance but if you run single nuts without hi preload you will still have some backlash.
Getting the ball nuts pre loaded with hi preload cost even more. Going to double nuts is even more so you soon have screws that cost $500 each.

If you guys had a choice to make of price performance what might that be? You do have to keep in mind that all these mills are still hobby level and not 4000 pound VMC's.
Thanks
Dave Clements- arizonacnckits.com

 

[Crazy Cat]

Wow! I didn't know about any of this drama. I ordered a kit with the standard screws a couple of months ago anyway, maybe before he had died, and it showed up in less than a week. It definitely isn't a quick bolt on though, and I havent dug into the Z axis yet, but the X and Y are on and work well. There was some modification required, thats for sure. I had to modify quite a bit, but I thought that was just expected with these kits. I still have to do the control cabinet, but I got the servos set up on the bench running and calibrated and it seems to work nicely. I'm using an ESS, a C82 BOB, and Allen Bradley 3000i servo's (2090-dsd-020 drives and 850 watt servos). It has been a boucou crapload of work for me, with arthritis and the cold, and I haven't even touched the Z axis yet, but man it is fun watching that table fly around!

I would give you (INTJ) my old X axis, but it is bent too! I got the mill for 850 bucks, but the X axis screw was bent.

 

[BehemothTheCat]

Dave,

As of late Bruce was selling the standard kit with C7 rolled screws for ~$1,000 and the premium one with C5 ground screws for ~$1,200. According to their website, both kits use double ball nuts. The premium kit, which I ordered, definitely comes with double ball nuts. I haven't measured anything, but backlash is imperceptible.

The mill itself is not super cheap and neither are the servos etc., so it was a no-brainer for me considering the price difference of $200. Would I have paid a $2,000 premium for better screws? I don't know, but would've definitely paid extra $400-$500 for half-decent angular contact bearings and couplings.

 

[kirkrockwell]

Hi Dave,
I bet you'll catch a bunch of us guys trying to do the PM-833T/V models! I am self taught / novice level at CNC. I started by building out a Sherline 5800 CNC ready desktop mill. Now that it's gone, I intend to use the PM-833TV build as both a continuation of the learning, and in support of my other hobbies and interests.

My build is going to be $10-$11k in parts and the CNC conversion kit from Bruce would be $1200 of that amount. My expectations are in-line with "hobby level" accuracy. My preference would be what looks like your standard 940 kit, that has the C7 ballscrews with double nuts set up to avoid backlash, and including the angular contact bearings. I intend to follow David Florians example, including the DMM servo upgrades. I think the X and Y were nema 34 with 1/2 inch shafts and a Z-axis nema 42 with 5/8 inch shaft. A couple hundred bucks either way isn't going to stop me from doing this.