Brilliant!! Shedding some weight with that huge block behind the spindle would be a good idea. Perhaps cut it into an "I-beam" with a hole (circular nuth'n fancy) down the Z.
XYZ travel in inches is technically 14x6x7 but if you take into account the bellows and enclosure and all the other little stuff that limits travel, it's realistically more like 10x5x6 of machinable area.
Nice, you had previously said that if you got into it with some perspective you would of gotten a proper mill. Would be interesting to hear your perspective on what you think the better option would be now. Would you buy a small mill and covert or build like you have (previous iterations and costs aside). I my self have a stock mini mill but haven't cut anything due to the play just from pushing the axis by hand.
Yes, I still think getting a proper mill and using it to build myself a CNC conversion would have been the better option for me. The only advantage to the path I took is that I was able to get into it initially with minimal outlay, and I didn't know I would get so interested in machining.
This is a heavy and strong machine, but using leadscrew doesn't seem good, you should try updating it to ballscrew, increase the accuracy and it will be better than leadscrew.
Epoxy granite would definitely lead to a more capable mill with much more mass and damping. It's probably not actually that much cheaper, and it's a bit more complicated. If I was going to start over and make another mill, I'd try it.
@@imnoexpertbut Nah. The epoxy is about $60/gallon and sand and pebbles is practically free. Since you have a CNC you can cut the molds without much thought. It's way easier than working with metal. It's a mix and poor operation. These guys built their own, but their epoxy mix was a bit too runny: ua-cam.com/video/FkGdJMVJ1Fc/v-deo.html. There quite a few videos on YT. The only thing really hard is the end result, epoxy granit CNC! This guy shows how cheap it is: ua-cam.com/video/ee7k1Vns9h8/v-deo.html
@@bobweiram6321 In the video you linked they still needed to purchase and machine steel parts that get embedded into the mixture. I agree the result is better, but I don't agree it's easier. Prove me wrong! Make one and upload a video about it. :)
@@imnoexpertbut It's funny you mentioned it. I'm still reorganizing my shop and it's hard to get everything up and running, but I will, at the very least, make a thorough build log. The machining of the steel is unnecessary, when you use precision milled stock and it is cast against a reference such as a granite plate. You might still need to scrape the mating surfaces, which can be done by hand. I think I said my piece and will leave you and your build alone. Have fun!
What a treat! I purchased the MiniMill last month and while waiting for some parts to arrive discovered your channel. I am already plotting my first upgrades following your lessons learned. Thank you for sharing your Fusion 360 drawing - it has been a great help in plotting the way! I have a ton of questions, but I will limit it to a few... Is there a reason why you chose an air-cooled spindle vs water-cooled? Also, did you go with the normal NEMA 23s from OB or the high-torque models? Have you investigated the benefits of using the external Stepper Motor Drivers like the DQ542MA from OB?
I chose air cooled because it's easier: no water pump, no water reservoir, etc. My air cooled spindle hasn't ever gotten very warm, let alone hot. I would recommend it. I got the normal NEMA 23s, although I just ordered a high-torque stepper for the Z axis after this latest upgrade because I can hear it straining a bit with the added weight of that solid aluminum "headstock" piece. I use external stepper drivers that seem similar to the DQ542MA that OB sells; they were TB6600 4 amp drivers on amazon that were super cheap. The TB6600 drivers I have work, but they aren't very good in my opinion, they are very noisy and have about 0.001" of positioning hysteresis. You should probably get the DQ542MAs!
That's a cheap granite surface plate. I thought it might make some difference because granite has damping properties, but it didn't do anything, so I haven't talked about it and later removed it. For chip evacuation I have compressed air going to a cheap amazon nozzle. I have the ability to do mist, but I almost always just do air blast, because the cheap mixing block I have doesn't do a good job of regulating the fluid amount, so I get a high amount of fluid in the mist and everything gets wet, which doesn't work great in an enclosure made from MFD panels. So far, air blast has been enough. Sometimes I'll spray wd-40 in if I'm doing something that needs extra help like slotting.
@@imnoexpertbut Sorry to bother you through here, I've replied to your build on Openbuilds but I saw you weren't much active there anymore so I thought I'd try through here: "Hey J**, did you design the 3d printed mounts for the bellows yourself? Any chance you could help a guy out with a model? How'd you mount it to the spindle mount? The holes for the LED-ring? Thanks" This question mostly pertains to the point where you haven't got full-diy yet and kept some openbuilds parts :P
Lead screws are cheaper and more compact, which allowed me to get more travel out of my small, simple design. Lead screws are also very hard for a load to backdrive, which I was worried about with the small nema23 stepper motors I was using at the time. I'd also heard some horror stories about cheap chinese ballscrews having a lot of backlash. I think leadscrews get a bad reputation because it's hard to secure them properly in the design; most router designs don't do a very good job at that and the leadscrews can rattle. Ballscrews usually come with bearing kits that are high precision and very secure. Once I improved how my leadscrews are secured the performance of the machine improved. Ballscrews are also much faster, but I'm not trying to do super fast rapids anyway.
@@imnoexpertbut Which nuts are you use to lead screw? I saw a black plastik small nut in aliexpress - and it doesn't look reliable and hard, i worry about lifetime this one.
@@GNOBLINYS I make my own nuts out of acetyl (delrin), with an anti-backlash feature like the ones openbuilds sells. They don't wear much because delrin has high abrasion resistance and low friction, and even if it does, you can fix it by adjusting the backlash mechanism: ua-cam.com/video/C6R8LHmDmfU/v-deo.html
On this point it is not upgrade anymore, this is totally new machine. Great job. Can you please share your drawings? I plan to make one.
Just wanted to say thanks for all the effort put into the videos, I really enjoy them.
You are expert. And genius to. Great information. Thank you for sharing.
Amazing! Have been looking forward to any more upgrades
Brilliant!! Shedding some weight with that huge block behind the spindle would be a good idea. Perhaps cut it into an "I-beam" with a hole (circular nuth'n fancy) down the Z.
Excellent content so far, keep making more :)
It seems to cut great! Do you have any pictures that show the surface finishes close up?
Hi, I'm building a similar machine and was curious how much travel you get on each axis!
XYZ travel in inches is technically 14x6x7 but if you take into account the bellows and enclosure and all the other little stuff that limits travel, it's realistically more like 10x5x6 of machinable area.
awesome vid!
Nice work! keep the vids coming :-)
what is the dimensions of the aluminum bottom plate.?
Nice, you had previously said that if you got into it with some perspective you would of gotten a proper mill. Would be interesting to hear your perspective on what you think the better option would be now. Would you buy a small mill and covert or build like you have (previous iterations and costs aside). I my self have a stock mini mill but haven't cut anything due to the play just from pushing the axis by hand.
Yes, I still think getting a proper mill and using it to build myself a CNC conversion would have been the better option for me. The only advantage to the path I took is that I was able to get into it initially with minimal outlay, and I didn't know I would get so interested in machining.
This is a heavy and strong machine, but using leadscrew doesn't seem good, you should try updating it to ballscrew, increase the accuracy and it will be better than leadscrew.
Next mill, epoxy granite. Surprised you didn't go with that option. Way more rigid, cheaper and endless possibilities.
Epoxy granite would definitely lead to a more capable mill with much more mass and damping. It's probably not actually that much cheaper, and it's a bit more complicated. If I was going to start over and make another mill, I'd try it.
@@imnoexpertbut Nah. The epoxy is about $60/gallon and sand and pebbles is practically free. Since you have a CNC you can cut the molds without much thought. It's way easier than working with metal. It's a mix and poor operation. These guys built their own, but their epoxy mix was a bit too runny: ua-cam.com/video/FkGdJMVJ1Fc/v-deo.html. There quite a few videos on YT. The only thing really hard is the end result, epoxy granit CNC! This guy shows how cheap it is: ua-cam.com/video/ee7k1Vns9h8/v-deo.html
@@bobweiram6321 In the video you linked they still needed to purchase and machine steel parts that get embedded into the mixture. I agree the result is better, but I don't agree it's easier. Prove me wrong! Make one and upload a video about it. :)
@@imnoexpertbut It's funny you mentioned it. I'm still reorganizing my shop and it's hard to get everything up and running, but I will, at the very least, make a thorough build log. The machining of the steel is unnecessary, when you use precision milled stock and it is cast against a reference such as a granite plate. You might still need to scrape the mating surfaces, which can be done by hand. I think I said my piece and will leave you and your build alone. Have fun!
What a treat! I purchased the MiniMill last month and while waiting for some parts to arrive discovered your channel. I am already plotting my first upgrades following your lessons learned. Thank you for sharing your Fusion 360 drawing - it has been a great help in plotting the way! I have a ton of questions, but I will limit it to a few... Is there a reason why you chose an air-cooled spindle vs water-cooled? Also, did you go with the normal NEMA 23s from OB or the high-torque models? Have you investigated the benefits of using the external Stepper Motor Drivers like the DQ542MA from OB?
I chose air cooled because it's easier: no water pump, no water reservoir, etc. My air cooled spindle hasn't ever gotten very warm, let alone hot. I would recommend it. I got the normal NEMA 23s, although I just ordered a high-torque stepper for the Z axis after this latest upgrade because I can hear it straining a bit with the added weight of that solid aluminum "headstock" piece. I use external stepper drivers that seem similar to the DQ542MA that OB sells; they were TB6600 4 amp drivers on amazon that were super cheap. The TB6600 drivers I have work, but they aren't very good in my opinion, they are very noisy and have about 0.001" of positioning hysteresis. You should probably get the DQ542MAs!
How about that pushtest? :P
Whats the big black block the mill is mounted on? and whats your blower setup for chip evac?
That's a cheap granite surface plate. I thought it might make some difference because granite has damping properties, but it didn't do anything, so I haven't talked about it and later removed it. For chip evacuation I have compressed air going to a cheap amazon nozzle. I have the ability to do mist, but I almost always just do air blast, because the cheap mixing block I have doesn't do a good job of regulating the fluid amount, so I get a high amount of fluid in the mist and everything gets wet, which doesn't work great in an enclosure made from MFD panels. So far, air blast has been enough. Sometimes I'll spray wd-40 in if I'm doing something that needs extra help like slotting.
@@imnoexpertbut thx for the reply :) do you use a large compressor for the compressed air? I dont ever hear it in your videos
@@YanouFishel It's an 8 gallon California Air Tools compressor and it is very quiet.
@@imnoexpertbut Sorry to bother you through here, I've replied to your build on Openbuilds but I saw you weren't much active there anymore so I thought I'd try through here: "Hey J**, did you design the 3d printed mounts for the bellows yourself? Any chance you could help a guy out with a model? How'd you mount it to the spindle mount? The holes for the LED-ring?
Thanks" This question mostly pertains to the point where you haven't got full-diy yet and kept some openbuilds parts :P
@@YanouFishel Here you go www.thingiverse.com/thing:4135825
Why did you not use ballscrew?
Lead screws are cheaper and more compact, which allowed me to get more travel out of my small, simple design. Lead screws are also very hard for a load to backdrive, which I was worried about with the small nema23 stepper motors I was using at the time. I'd also heard some horror stories about cheap chinese ballscrews having a lot of backlash. I think leadscrews get a bad reputation because it's hard to secure them properly in the design; most router designs don't do a very good job at that and the leadscrews can rattle. Ballscrews usually come with bearing kits that are high precision and very secure. Once I improved how my leadscrews are secured the performance of the machine improved. Ballscrews are also much faster, but I'm not trying to do super fast rapids anyway.
@@imnoexpertbut Which nuts are you use to lead screw?
I saw a black plastik small nut in aliexpress - and it doesn't look reliable and hard, i worry about lifetime this one.
@@GNOBLINYS I make my own nuts out of acetyl (delrin), with an anti-backlash feature like the ones openbuilds sells. They don't wear much because delrin has high abrasion resistance and low friction, and even if it does, you can fix it by adjusting the backlash mechanism: ua-cam.com/video/C6R8LHmDmfU/v-deo.html
@@imnoexpertbut What did you do thread into nut for lead screw?
Some special tool for cut thread?
@@GNOBLINYS You need to watch the video! :D I used an M8 2mm pitch 4-start trapezoidal lead screw tap I found on ebay.
Did you change your spindle?
Yes, I got a 1.5kW air cooled spindle and VFD kit from amazon. Having precise RPM control and a full set of collets is nice!
@@imnoexpertbut can you link it
@@eackerw85 Note, it's a 110V motor and VFD, not 220V, because all I have available in my garage is 110: www.amazon.com/gp/product/B06Y42QL2R
@@imnoexpertbut thank you, the 110 works better for me also