"One Perfect Part at a Time"


It’s All Resonant?

I am having some thoughts that the HB2 stepper problem may be part of the stepper resonance phenomena. The two Y axis motors on separate channels but running in tandem may be creating a mechanical resonance between them. Kind of like tuning both engines to the same RPM in a twin piston engine aircraft. There is a “beat note” low frequency resonance between the engines as they approach the same speed. (I am a pilot.) The same effect occures in a twin engine boat.

The same holds true when tuning a CW frequency in amateur radio. Another frequency (BFO –Beat Frequency Oscillator) is offset about 600 Hz so the signal can be heard. In older radios it was possible to tune the BFO to the exact (beat) frequency and when very close you would hear “wow, wow, wow” beat frequency of a few Hertz beat. (I am also a ham radio operator)

That beat can get fairly strong and become resonant. I think this may be contributing to the stepper resonance sensitivity. The issue is the two Y axis steppers HAVE to run at exactly the frequency so they could be adding to each other’s mechanical feedback. Then suddenly one stepper falls into its resonance “hole” and quits, just stalls. All my crash stalls have been on the tandem Y axis. It doesn’t happen very often so it is hard to prove.

This is all wild and just slightly educated speculation. I can’t find any real data on the Internet about tandem drive resonance but will say it has to be there. Large machines may be able to absorb such resonant frequencies or damp them. My tandem Y stepper steps have ALWAYS sounded louder than the other single drive axis and I don’t mean just because of the sound… Continue reading

Metric Thinking

I have been selling some metric tools (Proxxon) and actually using them too. I have discovered it is actually quite easy to work in either metric or SAE (inch) standards. There is no evil in either. I (almost) hate to admit I enjoy metric.

Of course the U.S. general prejudice to metric stemmed from our indoctrination, from what I now view in retrospect, to be a very lame educational system of the time. Post WWII there was a push for the USA to go metric. The requirement was to teach young children to exactly convert through (then) seemingly complex formula from one system to another. Remember, there were no calculators in those day. I could derive the equivalent answer but it made no sense why we would want to do this. The same thinking was crammed into our brains about temperature conversion.

In those days a student was not permitted to question the process but only to do as instructed.

As in learning a new language, it is very cumbersome to convert every word from one language to another. You only become efficient when you start thinking in the other language without the conversion. That is how metric should be understood.

I learned Morse code as a radio amateur. All radio operators will tell you that you do not become proficient until you stop counting dots and dashes and start “hearing” the sounds of letters. The really good can hear words. The very best hear Morse as a conversation.

When using metric hand tools I do not think of what millimeter is equal to in inch measurement. A good mechanic looks at a bolt and can say it is ½ inch or 12 mm, not stopping to think they are almost the same. When cars started using a lot… Continue reading

Weekend Puttering

While waiting for the new stepper couplings for the HB2 to arrive, I decided to do a little house cleaning around the shop. After pushing things around for a few hours, and sucking up what debris I could with the shopvac, I figured I should lube the ways on my machine tools. I can appreciate a one shot lube system as I have to do mine the long slow way. I finished and every machine is operating pretty slick now…

I spent a lot of time detailing out the Taig CNC mill. It is still in wonderful shape after all the machining it has done. That is really a great little milling machine in its size and class. I had to fire it up with the MACH3 in control and it wasn’t long before I was dreaming about the next project I should be running in CNC on that machine. In fact I “air cut” a couple of projects just to give the parts (mechanical and electronic) a little work out. It runs so sweet!

I have added a new Proxxon rotary hand tool to my workbench. I have more than I can handle (literally) but there is always room for just one more. This new tool is the Proxxon Micromot 50/E low voltage rotary hand tool. This is the first one of the 12-18 volt tools I have tried and I am amazed!

I already have and operate the Proxxon IB/E professional 120 Volt rotary tool. It is wonderful and definitely exceeds my two Dremel rotary tools in quality.

The 50/E is about ½ the size and power of the IB/E but is every bit as good. It is lighter, smaller and easier to hold for long periods of detail rotary work. I think I will prefer using… Continue reading

X3 Lighting Damage

The X3 mill motor controller was damaged in a lighting strike that took out a lot of electronics in my home. Mostly all the phone, computer and amateur radio gear. It also did some damage in the workshop.

The overhead door opener went out and had to be replaced. Here is the visual damage to the X3 motor controller board. The arc traveled between the solid jumper wire and the trace below which is ground.

The shop light transformer just burned out today. So the repairs are not finished. The new board is worth about $180.00 if it can’t be repaired.

Just another adventure after another… 🙂


Here is a picture of the backside of the board. I found another blown trace. Who knows what is also blown in those SM (Surface Mount) components. I was checking out having the board tested and repaired but now I intend to replace this board.

You know how it goes. Fix the obvious then other things start to fail like a week later. Not worth the time or aggravation…

Fading Light

TEDEX may slowly fade into the sunset. It is a web forum I started about five years ago, sharing information about machine shop hobby activities. I had already shared web space in my The Hobbyist’s Machine Shop web site with about eighteen people with projects and equipment they wanted to show off. I figured I could provide a separate forum where everyone could enter their projects and share information.

That is the reason TEDEX was born. Little did I know then that the creeping crud was laying-in-wait to slither into open forum doors. It has been a constant challenge to stay clean and probably the main reason many small forums shut down. For them, the Internet garbage collection just isn’t worth the effort.

I persevered because there were enough active users to justify the cause. That just isn’t the case any longer. I started a blog (two actually) here where I post my personal activities. I am torn to re-post again in TEDEX.

Registration to TEDEX is currently turned off. Registered users can still have full access. Non users can enter but do not see the photos. I dropped about 100 old non-participants from the rolls. The house has been cleaned and the doors locked. There are still a few resident suspects but I will see how they behave. The good guys still have the keys and can share the space.

If there are no postings or knocks at the door I will just let it set for awhile. Then…

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