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  1. pugap

    Swaging guidelines

    Does anyone know of textbook type tables that give guidelines to hole size, material thickness, and pin or tube diameters for swaging operations? Something akin to what you find for riveting.
  2. pugap

    Rigid vs floating vibration measurement

    We are looking for the correct means of measuring vibration in terms of should the object be rigidly mounted or can it sit on a foam pad. The objects are either small psc motors (42, 48 frame) or motor/blower wheel assemblies. Based on different person's experiences, we debate on whether the...
  3. pugap

    Alternate tests to hi-pots

    oldfieldguy I misread your post and was referring to winding resistance. There's no questions or issues there.
  4. pugap

    Alternate tests to hi-pots

    48 frame PSC, low (230V) and high (575) voltage applications. No where near gigaohms, more like 40-80 ohms per winding (depending on HP, voltage, etc). OEM testing is being done with the end unit as part of the final unit inspection. Hipot failures are typically assumed to be from the motor...
  5. pugap

    Alternate tests to hi-pots

    It is a when the motor is not passing the leakage current spec during installation into the final oem product. The motor manufacturer and the oem have the same leakage spec, but the oem "fails" motors that the manufacturer has passed. So the issue is to find another means of testing to verify...
  6. pugap

    Alternate tests to hi-pots

    Looking for alternate ways of verifying a hi-pot failure, aside from tearing the motor down or rehipoting. When a hipot failure is found, I'd like to verify if it the findings. You could tear into the motor to look for stray wires and such, but you can get into warranty issues with the motor...
  7. pugap

    Mysteriously Moving Controls

    A couple of us are co-creating a form in Excel with check boxes, drop downs, etc. What little functionality we have we wanted to keep simple by triggering macros off of the controls rather than writing code, therefore we initially decided to use control objects rather than form objects. What's...
  8. pugap

    How to use sound quality for evaluation

    Sound quality is a relatively new measurement technique being touted (see B&K), and I was wondering if anyone had any experience with it. The way it's been described to me, it is like taking some combination of subjective statistics (i.e. ranking human perceptions of sounds) and traditional...
  9. pugap

    Assembling a deck of cards

    There's an "oh by the way" (isn't there always?). One of the mates is a relationship between planes so that as a card is added, it is rotated or skewed at some angle from the previous, kind of like a spiraling staircase. Linear pattern falls short. My mates are 1)concentric for a hole in the...
  10. pugap

    Assembling a deck of cards

    Looking for tips on how to create an assembly of something analagous to a deck of cards. It would essentially be one card inserted X number of times, with different configurations being the number instances. What I'm looking for are tips on creating the mates without repeating the steps dozens...
  11. pugap

    How to use sound quality for evaluation

    How can sound quality be used to solve a noise issue vs using sound power/sound pressure? Situation where us vs "other guy", our product has a better sound pressure spectrum, but theirs "sounds" better. We look at the narrow band spectrum to look for the exact frequencies, and across the board...
  12. pugap

    Rotor coatatings

    I recently came across this thread, thread237-82751 , and found the last comment to be very interesting. Has anyone heard of anything like this happening in the field, where a paint is being used that outgasses chlorine at temperature? Opinions?
  13. pugap

    Electrical Noise - Sleeve vs Ball Bearing

    The wave forms I typically come across, and is true in this application, have a lot of ringing and are not clean. It's just the way it is (sounds like a business opportunity for you ;)). Thus we deal with noisy motors due to saturation from the dirty waveform. We have no say or control over...
  14. pugap

    Electrical Noise - Sleeve vs Ball Bearing

    The controller chops the waveform so that it is no longer sinusoidal - very common situation. The more choppy, the more saturation is induced. I think you are thinking of a variac, which controls the line voltage. The situation is application specific, which means all motors, not two...
  15. pugap

    Electrical Noise - Sleeve vs Ball Bearing

    The motors are identical in every way (same stack, same winding design, etc) except for the bearing system. The application required that the original design (sleeve) be changed to a ball bearing. Magnetic saturation of the steel is fairly common with PSC motors (though typically easy to...
  16. pugap

    Electrical Noise - Sleeve vs Ball Bearing

    We have an application utilizing a PSC motor with a type of triac type speed controller. The application is a motor in a blower, and the speeds run dictate that a ball bearing design should be used. Situation is that if a motor with a ball bearing construction is used, the motor is noisy (low...
  17. pugap

    Limit style tolerancing vs bilateral

    EngJW - Your perspective was felt by the majority here, so we're going back to predominantly ± tolerancing. It became too much hassle when it came to the cad drawings and having something drawn to scale - just like your example. We may still have some limit dimensions, but we'll use them where...
  18. pugap

    Limit style tolerancing vs bilateral

    ajack1: Interesting point on the SPC. I don't think anyone has looked at it from this standpoint. Looking at the bell curve (in my example) of a .4998 +.0001/-.0005 design nominal part has a different meaning than the data using a .4996±.0003 nominal value part. Right?
  19. pugap

    Limit style tolerancing vs bilateral

    That's the crux of the debate. The majority of the engineers are against the limit style, but the drive from the group developing the standards is to dimension prints to help manufacturing/inspection.
  20. pugap

    Limit style tolerancing vs bilateral

    Agree, but the question is if someone sees a drawing with the part toleranced as .4999/.4993, how are they supposed to know to model it as .4998 (design intent) instead of .4996 (middle value)?
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