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  1. T

    How do you turn a barrel with out chatter?

    Without seeing your setup it's hard to tell. Chatter is basically caused by taking too heavy of a cut in a setup that isn't rigid enough for the cut. So you are going to want to use steady rests if you are turning between centers, but better to just chuck the thing in a lathe as short as you...
  2. T

    Victor 400x750 lathe timing belt?

    Well timing pulleys aren't expensive either. I was able to find all the change gears I need (for metric threads) from Taobao for 1/10th the price the Taiwanese dealer wanted to charge me for ONE gear. The only problem was the 43 teeth pulley was not available with the center hole being 50mm and...
  3. T

    Carbide vs HSS

    Because all the googling didn't really solve my quest as to what inserts would give me a good finish. Lots of advise that doesn't work, and no real guide as to what chipbreaker geometry means.
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    Carbide vs HSS

    I'm going to chime in here, I been machining annealed 4140 and was having trouble getting a good finish as well until I found the following: Chipbreaker geometry matters. Look for something like this: I used that very insert and was able to get a very good finish at 1000+rpm, and low (about...
  5. T

    contactor/timer for starting capacitors for RPC

    No I never married. Women don't like guys who likes to machine stuff or are into guns...
  6. T

    contactor/timer for starting capacitors for RPC

    Well, I wired the contactor in parallel across all three contacts (the start cap uses only one wire) to spread the current out. No stuck contact so far. I did however manage to blow a breaker because I was confused by the design of the contactor, instead of one lead on top and one on bottom...
  7. T

    contactor/timer for starting capacitors for RPC

    My RPC is basically a static phase converter with a couple of idler motors. I can start it without the start capacitor but it makes really bad sound for a couple of seconds before starting. I'm concerned about damage to the motor if I keep starting it this way. Or if I put a centrifugal switch...
  8. T

    contactor/timer for starting capacitors for RPC

    So I have a RPC that right now I must manually shut off the start capacitor when I start it. The problem is when I shut it off the switch arcs a LOT. Like spark flies, IT'S ALIVE!!! kind of spark. I want to use a timer and a contactor, but I am concerned about the contactor arcing and being...
  9. T

    Lathe speed change while running (no clutch)

    My victor is used in Taiwan, and it seems they are different than ones you guys use. In Taiwan we don't use a camlock nose for example, but A1-6. I don't know what the motor is rated at because I'd need Superman to lift the lathe up, to look at the motor name plate. The motor is mounted in...
  10. T

    Lathe speed change while running (no clutch)

    Input amp is 40 amps...
  11. T

    Lathe speed change while running (no clutch)

    It would spin up but it seems the amp draw is too high and it cuts out before it's able to fully spin up. At all other speed it's fine but 1800 rpm would only spin up halfway before the breaker trips.
  12. T

    Lathe speed change while running (no clutch)

    So how do you soft start on a RPC?
  13. T

    Lathe speed change while running (no clutch)

    I ran 2 5HP motors in the RPC, tried a third, but the problem is even with the 2 extra motors, the highest speed would not start at all...
  14. T

    Lathe speed change while running (no clutch)

    Problem is Victor lathes have a bunch of relays and contactors that controls every aspect of the machine, and using a VFD is too complicated. So I wouldn't have a clue how to wire it so that a VFD can use it safely. The breaker is tripping in the wall. I think the motor is 5HP but I don't know...
  15. T

    Lathe speed change while running (no clutch)

    My new to me victor lathe does not have a clutch (I don't think any of them do). But here's the thing, because I do not have 3 phase I have a rotary phase converter to make the needed 3 phase. However on higher speeds the lathe do not start reliably, meaning it stalls out then trips the...
  16. T

    Chinese insert vs American/Japanese?

    USA is already 90% there. 9/11 has created the perfect excuse for vastly expanded government power, and the people want more.
  17. T

    Chinese insert vs American/Japanese?

    I don't do production, I might turn stuff for customers but a single WNMG will likely last me a very long time. Anyways one update on my lathe is it comes with timing belts instead of gears to power the gearbox. It didn't come with any change gears so I found a supplier who sells them. They...
  18. T

    Chinese insert vs American/Japanese?

    Basically they choose WHERE they buy it carefully. Platforms like Taobao does little to stamp out counterfeit items, but T-Mall (which is owned by the same company that owns Taobao) has strict policies regarding counterfeit, in that if the purchased item is found to be counterfeit the seller...
  19. T

    Chinese insert vs American/Japanese?

    Right now I am using some Chinese insert. Bought it from Taobao, costs about 10RMB. It works well if you use the speed and feed it recommends, and on the right material too (it tells you what material it's for, for example any steel under 40HRc, or aluminum (it looks shiny)). I'm also using some...
  20. T

    Chinese insert vs American/Japanese?

    Right now I live close to Huilong MRT station which about 5 MRT stations from Sanchong. Sanchong bus tends to have really aggressive drivers for some reason. Anyways I don't really care too much about politics but my family is basically KMT fanboy, as my parents are military officers (you have...

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