Shopmaster Mill-turn Any Input From Owners???

Seabee-ken

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I am a renter and currently own an older Shop Task from 1996. I took the mill off the combo unit and chucked it years ago when I bought a Jet JDM18 mill with a power feed. I am moving about 200 miles and am tired of moving both the mill and lathe and the biggest complaint is the space constraints of the garages I usually rent. I am seriously considering the new mill-turn but I cant find any input from folks that have one. I use my lathe 90% of the time so the need to have two separates isn't that big of a deal for me.
Just looking for input, thanks a bunch.
 
well funny you should ask. I was just popping a note to a few friends tonight about this very subject. CNCzone shoptask forum is the official forum. JT is on there occasionally but does not post much. a guy or two on there posted some stuff (not too promising but not overly horrible either). I'll say I have asked directly on that forum and did not get any reply as yet??? You should definitely ask there.

Best,
CG
 
I wish I had noticed that I live in the same town as you 5 years ago. I had a 2004ish Bridgemill then but have a 2017 Mill Turn now.

Bridgemill.JPG

Mill turn.JPG
 
I am a renter and currently own an older Shop Task from 1996. I took the mill off the combo unit and chucked it years ago when I bought a Jet JDM18 mill with a power feed. I am moving about 200 miles and am tired of moving both the mill and lathe and the biggest complaint is the space constraints of the garages I usually rent. I am seriously considering the new mill-turn but I cant find any input from folks that have one. I use my lathe 90% of the time so the need to have two separates isn't that big of a deal for me.
Just looking for input, thanks a bunch.
I purchased a 2019 Mill Turn at the beginning of 2019. I had zero machining experience at the time, but wanted to learn CNC machining. I have a relatively small shop, so footprint was very important. I wanted a lathe and mill, so a combo made sense. I looked at all the combo mill/lathes on the market. The 2019 Mill Turn mill spindle is carried on a cast iron bridge suspended completely across the top of the lathe. It slides up and down on 6 supports (1.25" diameter, total 7.5") using two ball screws, one on each side. I thought that design would offer better accuracy than the type where the spindle is cantilevered over the lathe and is fighting gravity on the far end. For a "small hobby mill" the lathe and table are quite large. I didn't want a machine that limited the size of the work too severely. I also was fully aware that NO small hobby mill/lathe can compete with a commercial machine, but I did not want to pay the price of a commercial machine. I knew that any mill/lathe from China would have some quality issues, but determined to fix them all and use that as a way to become more familiar with the machine. (This would be necessary regardless of the Chinese brand purchased, actually.) I have used it for almost 2 years now and can give you an honest review. My first comment would be that, even though it comes with handles for manual use, if you want to do manual machining this is not the machine for you. There is no way to thread without CNC, for example. There is no cross slide, so cutting a taper on the lathe without CNC would be a real challenge. You can do some basic stuff with the handles. I purchased an iMach CNC MPG pendant to move the axes around, and I would highly recommend that addition for anyone purchasing a ShopMaster Mill Turn. I use Fusion 360 to model and generate G-Code for most of my projects, and I use the MPG rather than the handles for simple stuff. The mill bridge is heavy, and even though it is supported with gas charged supports, the Z axis cannot move as fast as the X and Y axes, and it was plagued by missed steps until I configured the velocity and acceleration WAY low. I replaced the original stepper motor on the Z axis with a more powerful one from eBay (you are limited to 3.5 A/phase steppers unless you want to replace the entire Gecko 540 stepper driver with a different system). The larger motor doubled the speed and acceleration that I can use on the Z, but I still can't push it because missing steps on the Z axis is the biggest issue with this machine out of the box. So the Z rapids leave something to be desired, but it is now fast enough for any feed speed I typically use. I initially had very bad backlash in the X axis (over 0.003") and finally took the machine apart far enough to see that there was a damaged bearing on the fixed end of the ball screw. JT said he has not seen this before, probably damaged during installation or shipping. I replaced it and now I have 0.0015" backlash, much more acceptable. I use GWizard to calculate my feeds and speeds because, as I mentioned, I was a total newbie to machining when I started. I have found that when I use the settings in GWizard for a small hobby lathe/mill I can get recipes that provide excellent finishes on 1020 steel with carbide inserts (which is mostly what I have been cutting). The rigidity is an issue (on ALL Chinese hobby lathe/mills, not just this one) so the depth of cut and stepover have to be smaller than you would take on a commercial machine (Duh). But with CNC capability, a few more passes is no big deal, the machine is turning the crank, not me. I just go do something else while the part is being created. So IMHO, the Shopmaster Mill Turn is a great hobby machine if CNC machining is what you want to do. If you have real-world machining expertise, you should have no problem making good parts if you respect the fact that it is only a 2 hp 1150 lb machine, and resist the urge to use recipes you use on the commercial machines you have used at your job. If you want to use it as a production machine, you have to realize that it will be slower than the commercial machine due to the smaller cut ap and ae that can be used because it simply does not have that kind of rigidity.
 
The mill bridge is heavy, and even though it is supported with gas charged supports, the Z axis cannot move as fast as the X and Y axes, and it was plagued by missed steps until I configured the velocity and acceleration WAY low. I replaced the original stepper motor on the Z axis with a more powerful one from eBay (you are limited to 3.5 A/phase steppers unless you want to replace the entire Gecko 540 stepper driver with a different system). The larger motor doubled the speed and acceleration that I can use on the Z, but I still can't push it because missing steps on the Z axis is the biggest issue with this machine out of the box. So the Z rapids leave something to be desired, but it is now fast enough for any feed speed I typically use.

Not sure if it would be of any help in your situation, but sometimes increasing the duration of the step pulse in Mach 3 can help significantly with fixing lost steps. I would imagine it could help in any system that you can control that setting in.
 
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