What's new

Search results

  1. J

    OT: how do you test an oxygen sensor

    Oxygen sensors of this type do measure the oxygen/carbon ratio, they are often a two wire affair, so grounding is not necessary. The element does need to be hot enough to give a proper reading, generally above .5V is carbon rich, while less than .5V is an oxidizing atmosphere. Heating the...
  2. J

    Looking to bring small scale annealing in house

    One of the problems with a non oxidizing electric kiln is, the heating elements rely on a layer of oxide to remain intact, they will quickly fail without this oxide layer, there are some coatings to slow this down, and I have heard doing an oxidization firing every several firings will allow the...
  3. J

    Where to buy Electric Heat Treat Oven Parts?

    Any of the big ceramic supply stores such as Sheffield Pottery can supply a variety of shelves, mullite and alumina shelves are the cheapest and least durable, silicon carbide are very durable, a little thinner and still easy to cut with a diamond tile saw, the advancer shelves are the most...
  4. J

    Square D, QO breaker panel safety recall, possible overheating & fire

    I noticed in the video he first says to torque the screws to 25 foot lbs, perhaps a little much, then later says 25 inch lbs.
  5. J

    Annular drill power feed rqmt.?

    I have used these for a long time, never with power feed. From the Milwaukee Steel Hawg instructions. " Do not use Steel Hawgs with automatic feed operations, otherwise damage to the cutter or shank assembly may occur. Under very controlled applications, automatic feeding may be successful...
  6. J

    Repulsion Start Induction Motor needs a push to start.

    The spring that holds the copper fingers is in the right place, and if I change the brush position, it will start once or twice, then back to needing help.
  7. J

    Repulsion Start Induction Motor needs a push to start.

    The spring that holds tension on the brushes is intact and the brushes are good and free in their holders. once the motor starts, it runs fine, plenty of power, no bad smell when working under load for some time. After doing some research, it looks like the spring that holds the pivoting...
  8. J

    Repulsion Start Induction Motor needs a push to start.

    Repulsion Start Induction Motor needs a push to start, once running works fine,any ideas what to look at? under the commutator there are another set of loose copper pieces that look like they might seat in place when running? it has a spring near the loose pieces, should these be held in place...
  9. J

    Butcher-block workbench top repair?

    Some of the butcher block work tables are held together with steel rods, as well as being glued, the ends of the rods are covered by the outside strip of wood, might want to check that out before ripping.
  10. J

    3 phase motor runs slow.

    After getting it to make the motor run at some speed, go faster or slower, and reverse, the motor has almost zero power, (full power on the rotary) and have gone over the wiring and all the parameters many times, also the power requirements for the motor are much lower than what the VFD should...
  11. J

    3 phase motor runs slow.

    It's a cheap China VFD, Vevor brand, some of their stuff is pretty good, deciphering the instructions is a challenge, can always send it back if it don't work.
  12. J

    3 phase motor runs slow.

    Switched around the output wires on VFD and got it to work, I think, speed control works, and motor speed is better, but still seems slower than with the rotary, will have to check that out more tomorrow, output voltages from the VFD are stable now, but still not what I would expect, should that...
  13. J

    3 phase motor runs slow.

    Yes. When testing the voltage on the VFD while the motor was running this is what I got; Input, 240v Output, from ground to each leg 240V, 240V, 350V from leg to leg, 35v to 50V jumping around, 340V, and 100V.
  14. J

    3 phase motor runs slow.

    Tested the motor on the rotary power source and it works fine, there are no faults evident when checking the motor with a meter, the motor is wired 220v, and the VFD is 220v, the VFD is new, and as stated earlier, the VFD worked fine on a new ABB 3 phase motor, there is no load on the motor when...
  15. J

    3 phase motor runs slow.

    I have a 3 phase motor that runs very slow, maybe 200 rpm, it's new to me and it's my first time using a VFD, all my other 3 phase equipment is run on a rotary converter, but thought I would try a VFD for a variety of reasons. I tested the VFD on another motor and it works as it should, the slow...
  16. J

    OT: Keeping stationary diesel engine batteries in parallel charged

    Please disregard, I was thinking series.
  17. J

    Recommended grinding wheels for Darex M? drill sharpener?

    Looking at the instructions and parts list, it appears standard, CBN and diamond wheels were available from Darex for the machine, this manual might be for a later model than I have, hard to tell, from reading this manual, it would appear that the M4 came with standard wheels, as it references...
  18. J

    Recommended grinding wheels for Darex M? drill sharpener?

    What grinding wheels would you recommend for this sharpener? not sure if it is a M4 or M5, looks to use 6"x 3/4"x 5/8" wheels, not grinding carbide drills, just Cobalt HSS, etc. Just picked this up, looks to be in pretty good shape, needs a little cleaning, but otherwise ok, will be sharpening...