milling
Micro-milling Wax
Perhaps not worthy of a VMC but wax milling is a good job for a mill like the Taig. That implies the Taig is an excellent machine for the job.
As shown elsewhere in this blog, I have converted the standard Taig (not ball-screw) to a water-cooled spindle capable of 25,000 rpm.
The spindle is overpowered for wax milling. It just loafs along at near idle power. I turned off the water flow and let the mill run for an hour without water flow. The spindle became warm, but no where near hot. A lot cooler than the Taig standard CNC spindle motor doing the same work.
I have said wax milling is very low load, so this doesn’t surprise me. It tells me my cooling system is certainly far over engineered. Water flow is slow enough that wastewater (down the drain) cooling is certainly feasible for short to perhaps medium milling. The flow rate needs to be the smallest trickle. I would suggest collecting the (clean) water for plant watering or other uses.
Continue readingTormach xsTECH Router
A first impression. My impression. NOT a user report.
Note well: It called a ROUTER not micro-mill. Or any type of mill. Routers and mills are cousins, but don’t live in the same family group.
I was extremely excited when I saw this tool for the first time. I like Tormach equipment and I especially like their Linux based PathPilot controller software. This little baby OH router, the Tormach xsTECH actually runs full strength PathPilot!
It’s also a complete, full house, tools and all, everything one needs to get up and running — 3-axis micro overhead router. WOW! Continue reading
Machining in the 4th Dimension
The fourth dimension is often mentioned in science fiction as a dimension beyond the human senses. Today, real scientists (if there are such people) claim the fourth dimension does exist. But there are IMHO plenty of pseudoscience, especially promoted as video “entertainment.” Material for a future rant…
In machining there really IS a fourth dimension. Usually called the 4thaxis. The Hobbyist Machine Shop (THMS) has a fourth axis for use on the Taig micro mill. It’s been on both the mill used for metal machining as well as the wax milling machine. Currently it is on the Taig micro-mill used for wax carving
THMS has (owns) four software CAM software packages that can create g-code for the 4thaxis machining. I’ll list them but will not (here) get into the fine details of using them.
Two types of 4thaxis operations are most common.
First is indexing. The material to be machined is held in the 4thaxis rotational device. Standard X, Y, Z three axis machining is performed on the surface facing the Z axis. 3 axis machining is paused, and Z axis is raised to clear all dimensions of the material. The 4thaxis rotates (indexes) the material to another face. This can be 180, or 90, or 45, or any equal or non-equal rotation. Then 3 axis machining operation resumes on the new surface plain presented. Repeat as necessary.
The second process (A axis rotation) requires setting Z axis Y position perpendicular to the center rotational axis and A axis assumes the movements of the Y motion vectors by rotating. Where A axis was stationary in the first method, the actual Y axis is stationary in the second.… Continue reading
Ring Carved on 4th Axis
Everything came together for the first real use of the forth axis mandrel for ring carving. It’s nice when the plan comes together and everything works as intended. There was of course far more than just making the mandrel. There is the CAD design stage and the CAM (Desk Proto) for generating the G-code for the 4th axis. Then running the G-code on the micro-mill. I use LinuxCNC and I had to write my own metric post processor for Desk Proto. Not all that hard, actually. I made a USC (inch) version too. One tiny code change.
The first picture is the carved ring blank on the mandrel. I can accommodate a wide range of wax sizes. There will be much more experimentation and determination of the correct wax width for a project. This example worked fine.
The second photo is after the wax master model was hand finished and at this point is ready for casting. Sprue’s were added the ring put into a flask and the investment added. This post is not about the lost wax process. However, I thought it was interesting to show the wax carving and the final result the mandrel helps create.
The last picture is the finished Sterling silver ring shown on my hand (size 11). It really looks great. I will be doing a lot more wax carving on the 4th axis of the Taig micro-mill.
Taig 24K RPM Spindle Article Available
The full article on the Taig 24,000 RPM water cooled spindle conversion is now available on The Hobbyist Machine Shop website. Follow this URL:
https://thehobbyistmachineshop.com/cms/projects/high-speed-spindle-for-the-taig-micro-mill
The new spindle performance exceeds all expectations. It is not a low cost option / addition to an already adequate micro-machine tool system, but it does provide a very good way to achieve more than double the stock Taig spindle speeds.
Some applications using very small diameter tooling are performed much better when running adequate SFM and cut travel speeds. High speed spindles and especially water cooled ones like this example are a joy to use because of their extremely quite operation.
The Taig spindle is known for its quiet operation and the water cooled spindle here is in my opinion just as quite or perhaps more so, even running at full speed. Tool cutting sound is the same but the spindle motor has none of the sound of a high speed router.