Workshop
Just Add Water
The water cooling has been added to the high speed spindle through the red tubes in the picture. This is phase one where I will be using a reservoir with a sump pump behind the bench.. This should let me operate for maybe an hour or so. I don’t have any idea how much and how fast the water will warm.
The next step in the water cooling will be to add a closed loop system with a radiator to move the heat out into the ambient air rather than store it in the water tank. But first I need to determine through running and testing how much heat per hour is produced by the spindle in my type of operation.
I will be in the 10K to 24K speed range for many hours of continuous wax milling. I suspect spindle loads will be very low but only through running and testing can I design an adequate cooling radiator system.
Next is the spindle three phase wiring and power connection, followed by programming the VFD. If all goes well the spindle should be operational in a few more days.
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
What Excuse?
Ramblin’ Dan Today…
I try not to go on guilt trips. The view is depressing, and it doesn’t solve any problems if I am busy blaming myself. I can be guilty of many things, but I don’t have to ride the train… Uh, oh… speaking of trains. That reminds me…
I am guilty of putting my live steam and model trains fun on the back burner. Heck, there are a lot of things back there, just simmering. Some of them may be stone cold… Well, that’s the way it goes. I can’t feel guilty about not being able to eat everything at once.
A few people tell me they can’t imagine doing all the projects in which I have been involved. They don’t see the pile of “round-tuits” on the other side of the stove. That’s OK.
I really want to get back to metal working on the lathes and mills. Usually termed “machining.” Live steam is a great base for justifying detailed machine work. A live steam engine is an exquisite machine in its own right. Lots of moving parts and metal thingies to create from scratch materials.
My interest is as much if not more in the construction process as the finished product. A finished model is a reason to go start another project.
It was that way for me when I was very active in radio control model airplanes. Yes, I flew the heck out of my models, but the construction was where most of the enjoyment was created.
The lost wax silver work I do is the same thing. I like the creative process more than the finished jewelry. I love my creations, but I can’t wait to sell or give them to someone, so I can make more. I don’t collect my finished work.
Most… Continue reading