584,837 active members*
5,677 visitors online*
Register for free
Login
Results 1 to 14 of 14
  1. #1
    Join Date
    Mar 2012
    Posts
    51

    Question Tool Steel (D2,A2,4140)

    Does anyone have any experience with cutting tool steel on an 1100? When you calculate your speeds and feeds, how much of the available 1.5hp do you aim to use?

  2. #2
    Join Date
    Feb 2006
    Posts
    7063
    For any 3-phase motor with VFD "available" HP varies with speed. Below the motors rated base speed (the RPM @ 60Hz frequency), the motor is essentially constant torque, which means HP reduces linearly with decreasing RPM - at 30Hz, you'll have full torque, but only about half the HP. Above base speed, it's constant power, which means torque reduces linearly with increasing RPM - at 120 Hz, you'll have only 1/2 the torque you have at 60 Hz, but the HP will be the same. This all needs to be taken into account when picking RPM and feedrate. You're sometimes better off deviating from "ideal" RPM and feedrate to accommodate the motors characteristics.

    Regards,
    Ray L.

  3. #3
    Join Date
    Mar 2012
    Posts
    51
    Do you know if there is a graph or other information regarding the "available" hp at certain speeds? Or an equation I can use to figure it out?

  4. #4
    Join Date
    Nov 2005
    Posts
    157
    Some good information posted by 'Keen' in these threads. Haven't seen him on here in while though.

    http://www.cnczone.com/forums/tormac...teel_k600.html

    http://www.cnczone.com/forums/tormac...ned_steel.html

    http://www.cnczone.com/forums/tormac...ugh_steel.html


    I'm cutting a bit of P20 tomorrow, so I might chip in with what I find as well.

  5. #5
    Join Date
    Mar 2012
    Posts
    51
    Thanks Peter, that is some good information. Please let me know how you make out with the P20 and, if you are willing, the speeds and feeds you used.

  6. #6
    Join Date
    Feb 2006
    Posts
    7063
    Quote Originally Posted by adamboon View Post
    Do you know if there is a graph or other information regarding the "available" hp at certain speeds? Or an equation I can use to figure it out?
    Like I said, both relationships are linear. I don't know the specs for the Tormach motor, but let's assume 1.5HP, with a base speed of 3600 RPM @ 60Hz.

    Below 60 Hz/3600 RPM:
    HP = 1.5 * RPM / 60HzRPM
    Torque = HP * 5252 / 3600

    Above 60 Hz/3600 RPM:
    HP = 1.5
    Torque = 1.5 * 5252 / RPM

    At 3600 RPM, you'd have:

    Power: 1.5 HP
    Torque: 2.18 ft-lbs

    At 2000 RPM, you'd have:

    Power: 1.5 * 2000 / 3600 = 0.83HP
    Torque: 2.18 ft-lbs

    At 5000 RPM, you'd have:

    Power: 1.5 * 3600 / 5000 = 1.08 HP
    Torque: 1.08 * 5252 / 5000 = 1.13 ft-lbs

    Regards,
    Ray L.

  7. #7
    Join Date
    Mar 2012
    Posts
    51
    Thanks for that Ray. Now I just need to find out the specs for the Tormach motor. I couldn't find it in the manual I downloaded, maybe somebody out there knows what it is. Now I can better calculate if my pretend speeds and feeds are within the capabilities of the Tormach.

  8. #8
    Join Date
    Dec 2007
    Posts
    30
    Hi Adam

    From the tech sheet on the Tormach web site
    100-5,100 RPM
    110ipm in x and y
    90ipm in z

    Max power 1.5hp

    Peter

  9. #9
    Join Date
    Jun 2006
    Posts
    2512
    You're trying to eat the elephant from the wrong end.

    Horse power calculations are very approximate. Horse power at the cutting tool is not the same horse power as at the motor. Whether you can use the available horse power depends on other factors not included in the calculator. Horse power calcs are only good for telling you if you are way outside or inside your limit. Constant torque to rated rpm and constant hp above rate rpm is more than close enough for your calcs considering all the other uncertainties. Hence the reason you can't find what you are looking for is because it is of low interest.

    Don't forget to allow for the speed difference between the motor and the milling spindle.

    Phil

    Quote Originally Posted by adamboon View Post
    Thanks for that Ray. Now I just need to find out the specs for the Tormach motor. I couldn't find it in the manual I downloaded, maybe somebody out there knows what it is. Now I can better calculate if my pretend speeds and feeds are within the capabilities of the Tormach.

  10. #10
    Join Date
    Mar 2009
    Posts
    1863
    Constant horsepower calculations don't mean squat if you're cutting D2. If your spindle speed is too fast, you'll fry your cutter in about 6 turns.

    A2 is a little more forgiving, and with the right tools, 4140 in an annealed condition and with the right tools can be at some fairly high feeds and speeds.
    You can buy GOOD PARTS or you can buy CHEAP PARTS, but you can't buy GOOD CHEAP PARTS.

  11. #11
    Join Date
    Nov 2005
    Posts
    157
    Went quite well, posted the pics/info in a different thread to avoid hijacking this one.

    Quote Originally Posted by adamboon View Post
    Thanks Peter, that is some good information. Please let me know how you make out with the P20 and, if you are willing, the speeds and feeds you used.

  12. #12
    Join Date
    Jan 2012
    Posts
    51
    Quote Originally Posted by HimyKabibble View Post
    Like I said, both relationships are linear. I don't know the specs for the Tormach motor, but let's assume 1.5HP, with a base speed of 3600 RPM @ 60Hz.
    Just for completeness on the motor topic:

    The motor is 1.1 KW, 230 V, 60 Hz, 1715 RPM, Delta config.

    I had a spectrum analyzer hooked up to mine to check unbalance, and the motor to pulley ratio was 1.26 (from the response peaks), on the high speed ratio.

    Tormach designed it to overdrive to ~140 Hz with the VFD. 1715 RPM * (140/60) * 1.26 = 5042 RPM.

    Regards,

    Geo

  13. #13
    Join Date
    Jun 2019
    Posts
    2
    A2:
    A-2 steel is an air hardening alloy chromium-molydenum-Vanadium die steel. As a cold work steel grade containing 5% chromium.
    http://www.otaisteel.com/products/co...ld-work-steel/
    D2:
    1.2379 die steel is a kind of high carbon high chromium alloy tool steel. It has high hardness and wear resistance after heat treatment, and has strong hardenability and good dimensional stability. 1.2379 die steel and NAK80 die steel are suitable for making. High precision long life cold working die and thermosetting plastic mold.
    http://www.otaisteel.com/din-1-2379-...21bohler-k110/
    4140:
    AISI/SAE 4140 grade is a versatile alloy with good atmospheric corrosion resistance and reasonable strength. It shows good overall combinations of strength, toughness, wear resistance and fatigue strength.
    http://www.otaisteel.com/products/qu...0-alloy-steel/

  14. #14
    Join Date
    Jul 2019
    Posts
    8
    H13 mold steel have good tempering resistance,high temperature wear resistance,good quenching and heat resistance impact resistance,high touhness,good Thermal cracking resistance.It can be nitrided to increase wear resistance. You can content Songshun steel to get h13 mold steel.
    Contact: https://steelpurchase.com/about-culture/
    Last edited by livonor; 07-04-2019 at 10:50 AM.

Similar Threads

  1. Turning 4140 steel
    By maximusek in forum MetalWork Discussion
    Replies: 5
    Last Post: 07-04-2019, 10:18 AM
  2. Where to buy 4140 PH steel small quantity
    By DMBGO in forum Want To Buy...Need help!
    Replies: 2
    Last Post: 07-21-2010, 11:14 PM
  3. Hardening 4140 steel spindle in kiln?
    By DennisCNC in forum MetalWork Discussion
    Replies: 1
    Last Post: 04-30-2009, 03:09 AM
  4. Boring a Hole in 4140 steel
    By ricotututi in forum MetalWork Discussion
    Replies: 13
    Last Post: 10-06-2006, 05:15 AM
  5. ACME - 1018 steel or heat treat 4140 alloy
    By CnC_BoY in forum Linear and Rotary Motion
    Replies: 3
    Last Post: 03-21-2006, 11:41 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •