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More often than not you have EMI problem, which worsens at low temperature. This is due to the higher currents of motors and other like VFD. In addition, the input trip point of electronic components...

Not quite sure how head nod is the dovetail’s inheritance. My smaller mill runs its Z on dovetailed column with no quill, and it did not even bother to nod - or bowing - to me.



What is the...

There is one thing I don't understand is that why adjusting the spring (I am assuming it is the pinion shaft coil spring) would help the backlash.

There are two backlash components, and that...

If I am going to add a couple of linear rails to the head to help the quill, I think it would be cleaner to add couple of rails to the X3 column as Ian's suggestion.

After some though it seems to...

Hmm, many RF3x conversions did just fine with the quill extended, and many X3 conversions did not do so good with the head nodding... It does not take a smart person to figure this out.

Thanks Bob. I like it, that is a good one and I have not seen anything like that before.


htrantx

I could not find those, do you happen to have the links?

Rong Fu 3x mill conversions commonly use the pinion drive with backlash, but I think X3 quill can be driven directly with a ballscrew.

I did find a retrofit BP with ball screw quill drive:

Details of Z Axis Conversion

It does not seem to be pretty at all.

" BTW, if you did fit linear rails to the head/column etc and removed...

Good points.

I bet Defeng, when working with Sieg designing the CNC SX3 mill, had probably wanted the liner rails installed to the X3 as he did with his SVM-2 ;).

You are right, driving the...

Looking for an example of X3 (or any mill) cnc conversion using quill drive instead of the Z column drive, but could not find it. It seems although the Z operation's travel would be limited with...

You have my sympathy, if your maintenance guy is correct. You are driving an old car, which has no seat belt. Your problem is staring at you in the face all the time… Inrush current kills.

Your...

Most data loggers has a RMS input stage, and since the tail of the RMS filter is much longer than a cycle, you cannot see the true sagging magnitude of a glitch in milliseconds.

The problem is...

The killer VSAGs are only few cycles at a time (0.01666 sec/cycle) as described in the papers. You need to set the sampling rate much faster than the nyquist rate to see them in the time domain. Use...

another paper:

IEEE Xplore - Understanding the dominant field failure mechanism for DC power supplies

Abstract:
... This paper shows that current-inrush surges, and not voltage surges, are the...

The following paper described the failure mechanism of your problems, and suggested some solutions.
...

The tb6600 output operation start at the rising edge of pin 21 (CLK in the datasheet). The TQ's time constant is activated by the same rising edge.

Lucas,

Good work on extracting the schematic from PCB.



The node at the collector of 3906, which has EN at the emitter, should be connected to GND.

EN transistor/resistor combo and TQ's...

riphet,

I suggest you read the following blog:

Slow, Mixed and Fast Decay Modes. Why Do We Need To Complicate Things? | EBLDC.COM

Which seems to be written for a high school class at the...

H500, you were right.

The equation in 11/13/2007 datasheet was a typo, and the spec was updated 03/24/09 and it is:

for 2-phase excitation:

P = VDD × IDD + (Ron(U + L) × Io × Io) × 2

I would say it is a little presumptuous for jumping into that conclusion.

It is what it is, an equation to estimate the chip's PD, I would say. Don't stomping down too much onto an empirical...

This should work:

Air Pump with Diffuser - 5500 cu. in. per Minute

ht

Phil, I think you were right on, and I did not disagree with your assessment of the mis-step due to ACR on the Allegro part. There are already numerous solutions to prove you were correct.

Please...

Thanks Folks.

It seems that 4 or 5in would be ok for a X3, so I bought a 4 in Dayton vise since the next size is a 6 in. For some reason I thought the vise would be Taiwan made, well, not a...

Thanks,

Anyway, reducing power during torque holding is an attractive power solution and should work with a decade old part like the TB6560 without problem like mis-stepping. Circuit and software...

Phil, only a senior designer like yourself would notice this bug. However it seems odd that the lag or latency would be more than one clock and can cause a mis-step. Since the TB6560 on-chip current...

---Any size is good... Dooh!---

Anyway, I think 6" is to big ( too much overhang), and 4 is too small. However; 5 seems not right for a X3 mill...

What do you think?

Ht.

Good point; I thought match pair should be /\ or \/, but never thought of a // match pair or a \\// match quad. Now I understand the pre-loading of the design.

Thanks,

ht

Sam & Dick Z, thanks, and too bad that they are >20 Deg

I have found pre-loaded DAC bearings specifically designed for spindles and ball screws at:
...

Before I write off the use of double-row angular contact (DRAC) bearings in a project, I would like to check with gurus in here first.

A standard DRAC bearing does not have internal pre-load, so...