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  1. I

    Measuring thread depth without wires - your views, please

    On my computer it brings up this;
  2. I

    Arduino Rotary Table

    I purchased this same rotary table about 15 years ago from Harbor Freight. It was made in India. It is very poor quality. I recall paying $90 for mine. The crank drive to the worm gear is very stiff, and there was too much backlash. Maybe the quality has improved. But mine sits on the shelf...
  3. I

    Arduino Rotary Table for Dummies

    I can't see any big differences between the Nano and Uno in I/O that would account for non operation. I would take a guess you have a ground not connected between the Nano and your stepper motor drivers. But I'm guessing without seeing your wiring diagram.
  4. I

    Valve seat material for B&S lawn mower engine

    Thank you for your post. I'm not wanting to fix a B&S as the OP is doing. I was looking for general information for the repair of the Onan engine. It's a very old design. Cummings bought them a few years back and stopped all parts deliveries. So it's make the parts or scrap it. But I was asking...
  5. I

    Valve seat material for B&S lawn mower engine

    My understanding is Stellite is a special conformal coating of valves to enable high temp operation. I've never heard of it in a solid form to make valves or seat from. I'll have to research that.
  6. I

    Valve seat material for B&S lawn mower engine

    I came to this post to see what sort of heat treat steel should be used to make a valve seat. I'm only seeing recommendations of using common pipe or ductile iron. I understand this is a cheap B&S engine, and disposable. I fix mine also. But a few years back I needed to make a new exhaust valve...
  7. I

    Tests of CDI Ignition Modules

    I was 'surfing' youtube and this channel came up with this about high voltage coil drivers; I hope this is of interest to this thread.
  8. I

    Tests of CDI Ignition Modules

    Those look very clean of noise. Looks like the low pass RC worked per design. So is that ringing frequency a function of your transmission line length, assuming it's the reflected wave bouncing back and forth?
  9. I

    Tests of CDI Ignition Modules

    I wanted to see what it would come up with. My career was doing the qualification testing of commercial avionics products (Shake, Bake, EMI per RTCA DO-160) as part of the FAA and EAA certification process for TSO or PMA products. I spent hours trying to fix EMI emissions and susceptibility...
  10. I

    Tests of CDI Ignition Modules

    Don; Other's may be interested in the technical aspect of making these measurements, so I'm replying to your post. For laughs, I asked openAI (ChatGPT) this question; "How to filter the broadband noise while measuring spark plug voltage and current in an experimental ignition system?" I got the...
  11. I

    Tests of CDI Ignition Modules

    Don, I'm curious to understand how you took your digital scope data loaded into Excel, and computed the Joules given a voltage and current waveform. Reference the first table, in your report in post #1. I'm guessing you are treating them as sine waves, and computing some sort of RMS averaging...
  12. I

    CNC motor Coupler Death and Repair

    These JAW type couplings will destroy the elastic spiders if they are out of alignment. They can't take more then a few thou of axial or radial alignment errors. If you can figure out how much misalignment you have between the motor shaft and load shaft, and correct this. You may have to shim...
  13. I

    Almost burned my shop down and didn't even know it

    If you have a brand name circuit panel, you can sometimes get used panel based breakers, they look just like the GFCI type, off eBay for less then the typical home store price, or buy in quantity. $45 is what I've see in my local Menards store, but Lowes and Home Depot carry them as well. I've...
  14. I

    Almost burned my shop down and didn't even know it

    My read on AFCI breakers, early versions had issues with universal motors as brush noise would trip them. They have evolved, I don't know about false trips. I have them in my addition as they were required, and have not had any trips with vacuum cleaners or other motors. My read is they look for...
  15. I

    Almost burned my shop down and didn't even know it

    Yes that's exactly what it is, Romex is a trademark name of the early company making it. NEC code refers to it as non metallic sheathed wiring (NM).
  16. I

    Almost burned my shop down and didn't even know it

    For reference in the USA and Canada that use the 120V split phase standard, arc fault fires have statistics indicating 50% of fires would be prevented by AFCI (arc fault circuit interrupt) circuit breakers (CB). In a WIKI article, this does not appear to be an issue in countries using the higher...
  17. I

    Almost burned my shop down and didn't even know it

    There is no NEC requirement (kitchen) for this that I've ever been aware of or can find. The reference in the NEC 210.4(B) requires that the two ungrounded wires which are sourced from circuit breakers will simultaneously trip if a fault should trip one. I just wanted to comment so this is not...
  18. I

    Almost burned my shop down and didn't even know it

    Was root cause ever found?
  19. I

    Almost burned my shop down and didn't even know it

    <snip photos> Lloyd, I don't think this happened while your lathe was running, you would have seen the smoke and the horrible electric smell of the plastics burning. My guess is that the plastic internal to the duplex wiring device had some FOD that created a current leakage soft short between...
  20. I

    New to me Mill

    VFDs intended to run on single phase input, only need to be oversized for use over 3HP. The input rectifier diodes are what limits this, and they are oversized for units below 3HP to operate without damage.
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