CAD/CAM/CNC
24K Spindle Progress
The parts arrived yesterday. Exactly as shown in the previous post. I placed an order for some four conductor cable for the wiring between the Variable Frequency Drive (VFD) and the spindle motor.
I needed to see the clamping size of the spindle’s electrical plug connector. I didn’t want to select and order a cable that would not fit. The cable is on they way to me, so I created the adapter I needed to mount the new spindle on the Taig Micro-Mill.
The picture shows the results of my work as the spindle is now nicely mounted on the mill.
After I am finished with all the mounting, wiring, and set-up… and I have the new spindle working, I will write a detailed report on the mounting plate and all the work required in making the conversion.
I think the spindle looks like it belongs on the Taig!
High Speed Spindle
Here in the RD workshop, consideration is being made on adding a one horsepower 24,000 RPM spindle to the Taig CNC Micro Mill. The standard spindle is a belt drive one quarter horsepower unit with a top RPM of 10,000.
The standard spindle and drive is quite adequate for most of the milling work the micro mill is asked to produce. The primary use for one of my mills is wax carving with as small as 0.003-inch milling bits. That size mill bit can best operate at the 10K RPM and higher ranges.
I did some comparison of speeds and feeds in G-Wizard from CNC Cookbook. Doubling the spindle RPM can almost double my rate of travel, within limits of tool deflection, which is not extreme in wax. It will certainly reduce my running time.
The new high-speed spindle is a bit pricy. I’ll know the final cost if I decide to proceed with this quest for rotational speed. The little Taig mill doesn’t need more than ¼ HP for most of the work it performs. The Spindle I am considering is 800 watts which is 1 HP. It requires a VFD (Variable Frequency Drive) that produces 3 phase, 110 volt output and can vary its frequency output from between about 100Hz to 400Hz. The frequency change is what varies the speed of the spindle.
I am a certified commercial VFD start-up/commissioning engineer and have a very good understanding of how VFD drives function. I have not seen the VFD for this spindle, but its (published) operational parameters are familiar.
The spindle may have an issue for some folks. It’s not actually an issue, however. The spindle has an ER11 collet holder rather than the Taig ER16 size. That means the largest nominal size tool the high-speed ER11 collet… Continue reading
Dimensional Decision
I am presently using two very good 3-dimensional CAD programs. They are Autodesk Fusion 360 and Robert McNeil & Associates Rhino3D. I am at a decision point on which one will be my standard go-to drawing program.
I have had the longest association with Rhino. I started with version 3 and version 6 has just been released. Major version number upgrades must be purchased. That’s why I am at a decision point.
Fusion 360 is free for users like myself. That is a major advantage. The Rhino3D upgrade is $375.00.
It seems like a no-brainer to stay with the free one. But for me price is not always the sole determining criteria.
My problem is that both programs are very good. The largest difference is the cost-to-own. If I had to pay for Fusion 360, I must admit that cost would be a very large determining factor. I certainly don’t want to be paying for two programs that are almost equal in results for how I use them.
My decision is to continue using both. I will pay for the upgrade in Rhino. It’s about $1.05 per day for a year. I can live with that. Major upgrades do not occur yearly, so the cost spreads out thinner.
I have no idea if Fusion will remain free. It does seem to be a very friendly marketing strategy.
One hesitation I have with Fusion 360 is it is cloud-based and dependent on a connection to the Internet. It seems to me it access could be shut down very quickly. But every computer activity today depends heavily on an Internet connection. I feel any change in the free use policy won’t be immediate.
I have just changed my business accounting to a web-based service. It’s how we work today.
What keeps… Continue reading
The Way to Go
Choosing Proper Machine Way and Screw Lubrication.
RDS processed a half dozen orders for the new Taig ball-screw micro-mill. A question came to me from one of the customers, about proper lubrication requirement for the ball screws.
I have always used a 20 weight non-detergent oil on all my machine tools, which is packaged in small cans for the lubrication of electric motor bearings. I apply it on the ways as well as the screws and crank bearings. I did not know what Taig recommended for the new ball-screws and bearings.
I contacted Taig and a staff person gave me two options. One was #2 way-lube and the other was automatic transmission oil. The transmission oil was a surprise to me.
I check on the way-lube and discovered most suppliers sold it in 5-gallon pails for a bit over $100. Five gallons on a Taig mill is a lifetime supply. My lifetime anyway. I found a supplier on eBay that was selling it in two one-pint bottles. They are shown in the picture.
In the meantime, I had the transmission oil in my shop so I tried it. It is very slippery and seems to hold a good film. I didn’t test it in long term use. One slight drawback is the unique odor of transmission oil, and this brand was colored red. (That’s so car mechanics can tell by the color what oil is leaking.)
Taig recommends either oil but I think my preference is for the Mobil Vactra No. 2 way-oil. It’s the real thing. The five-gallon pail was a killer amount for me until I found a lower packaged quantity, but more expensive for an equal amount.
I thought of repackaging for my customers, but I am concerned about the shipping regulations. The oil is non-hazardous, but… Continue reading
Reader Email
I received a good question from reader feedback at Ramblin’ Dan’s Store. It was sent to me as a private email, but I think it is worth making my reply public. MPS2000 is a CNC micro-mill produced by MicroProto, the CNC division of Taig Tools. The question is about using a laptop computer for CNC control.
“Looking to see if there is a way to rum my machine (CNC Mill) from a lap top. Has the MPS2000 software been upgraded to true 3D?”
My reply,
Not sure of your question of “true” 3D. I don’t use or support MicroProto (MPS) controllers and am unaware of any (perhaps hardware?) issues about 3D mill operation and the MPS controllers. The software is MACH3 which can certainly run 3D CNC action in 3 or 4 axes on a single parallel port. I have been doing it for nearly 2 decades.
There may be purest fanatics with certain micro accuracy issues with MACH3 and such things as trajectory planning and my answer is, “don’t use it if it is a bother.” In practical use, it works fine for the hundreds of projects I have run. (Because of issues with Windows 10) I recently switched to LinuxCNC. Not perfect either, but is works for what I need. 🙂 BTW… I don’t recommend LinuxCNC to a non-programmer unwilling to hack code.
Tormach for example, has switched to their own (self-supported) version of Linux based CNC called PathPilot https://www.tormach.com/pathpilot.html
The problem with laptops is the built-in energy conservation techniques at the OS or hardware level that may shutdown ports or interrupt the critical pulse timing. Of course, laptops are being used, but there are too many variables for it to be recommended. One solution is to use an external pulse generator… Continue reading