Pulsar problems

Results 1 to 11 of 11

Thread: Pulsar problems

  1. #1
    Registered
    Join Date
    May 2017
    Location
    United States
    Posts
    18
    Downloads
    0
    Uploads
    0

    Default Pulsar problems

    I recently purchased a Novakon Pulsar a couple months ago, when I got around to setting it up the lever drawbar (LDB) acted "sticky" and the spring didn't return it to vertical (hadn't even run the tool yet, that was how it worked after I turned it on and move the z-axis up clear from the shipping block.

    I took the assembly apart and noticed that the cam inside it was bent and even with it off and everything disconnected (just the cam in the block between the two bearings), it wouldn't spin freely. John was nice enough to have a new cam, bearings, brass bushing, and clips sent to me. Assembled everything today, cam spins freely, attached arm. Went through the drawbar tightening procedure: Tighten it all the way, back it off 1 turn. Tighten the collar all the way down and then back it off 1 turn. Then I installed the LDB assembly on the tool. First pull is very "sticky" again, and it sounds like something is slipping. Took the LDB assembly apart again and noticed that the cam shaft is again bent, and the brass bushing has a flat on it (same problems I had with the original).

    Does anyone have a Pulsar with an LDB? Do you have problems with it? I'm actually super disappointed... the LDB was one of the reasons I went with Novakon over other brands (I don't have shop air where I am). I'm thinking that maybe it's just a bad design and very poorly machined - I mean the fit and finish of the Pulsar in general leaves some to be desired, but the machining on the LDB seems super sloppy.

    In any case, I took the entire LDB assembly off the tool, just to check if anything was wrong with that. I can't really see anything obvious wrong though. I did take a video looking up through the spindle assembly, and while the taper doesn't obviously look to have excess runout (don't have a dial indicator yet... I know, I need one, I'm very new to owning a mill. It's the first thing I'm going to buy when I get this damn thing finally set up), the bore where the drawbar sits seems to very noticeably wobble. Here's the link to the video ( ) - It was taken with my phone on a block pointed up through the spindle with the tool set to 100 rpm. Does that look normal? This drawbar problem has me wondering what other problems I might encounter with this tool.

    Anyway, thanks for any/all your help.

    Similar Threads:


  2. #2
    Member
    Join Date
    Aug 2007
    Location
    usa
    Posts
    701
    Downloads
    0
    Uploads
    0

    Default Re: Pulsar problems

    Quote Originally Posted by rickjamesbrown View Post
    I recently purchased a Novakon Pulsar a couple months ago, when I got around to setting it up the lever drawbar (LDB) acted "sticky" and the spring didn't return it to vertical (hadn't even run the tool yet, that was how it worked after I turned it on and move the z-axis up clear from the shipping block.

    I took the assembly apart and noticed that the cam inside it was bent and even with it off and everything disconnected (just the cam in the block between the two bearings), it wouldn't spin freely. John was nice enough to have a new cam, bearings, brass bushing, and clips sent to me. Assembled everything today, cam spins freely, attached arm. Went through the drawbar tightening procedure: Tighten it all the way, back it off 1 turn. Tighten the collar all the way down and then back it off 1 turn. Then I installed the LDB assembly on the tool. First pull is very "sticky" again, and it sounds like something is slipping. Took the LDB assembly apart again and noticed that the cam shaft is again bent, and the brass bushing has a flat on it (same problems I had with the original).

    Does anyone have a Pulsar with an LDB? Do you have problems with it? I'm actually super disappointed... the LDB was one of the reasons I went with Novakon over other brands (I don't have shop air where I am). I'm thinking that maybe it's just a bad design and very poorly machined - I mean the fit and finish of the Pulsar in general leaves some to be desired, but the machining on the LDB seems super sloppy.

    In any case, I took the entire LDB assembly off the tool, just to check if anything was wrong with that. I can't really see anything obvious wrong though. I did take a video looking up through the spindle assembly, and while the taper doesn't obviously look to have excess runout (don't have a dial indicator yet... I know, I need one, I'm very new to owning a mill. It's the first thing I'm going to buy when I get this damn thing finally set up), the bore where the drawbar sits seems to very noticeably wobble. Here's the link to the video ( ) - It was taken with my phone on a block pointed up through the spindle with the tool set to 100 rpm. Does that look normal? This drawbar problem has me wondering what other problems I might encounter with this tool.

    Anyway, thanks for any/all your help.
    Mine never really worked right. The design isn’t robust enough although a good idea in theory. Save yourself a headache and spend a day building a power drawbar. I posted the cad files and it was the best upgrade besides pathpilot I did to my pulsar.



  3. #3
    Registered
    Join Date
    May 2017
    Location
    United States
    Posts
    18
    Downloads
    0
    Uploads
    0

    Default

    Quote Originally Posted by brianbonedoc View Post
    Mine never really worked right. The design isn’t robust enough although a good idea in theory. Save yourself a headache and spend a day building a power drawbar. I posted the cad files and it was the best upgrade besides pathpilot I did to my pulsar.
    I'm wondering if the offset bore for the drawbar (can be seen in the video) is causing the drawbar to bind. It would have to fit at an angle when a collet was installed and it would rub in the upper part of the spindle. Maybe that's why I need to apply more force than the ldb can handle.

    I like your power drawbar. I'd build one right now if I had air in my shop, but this thing is currently in a place where I can't have a compressor running all the time. Also, if the issue is what I think then I feel like novakonak should probably replace the spindle.



  4. #4
    Member
    Join Date
    Aug 2007
    Location
    usa
    Posts
    701
    Downloads
    0
    Uploads
    0

    Default Re: Pulsar problems

    Quote Originally Posted by rickjamesbrown View Post
    I recently purchased a Novakon Pulsar a couple months ago, when I got around to setting it up the lever drawbar (LDB) acted "sticky" and the spring didn't return it to vertical (hadn't even run the tool yet, that was how it worked after I turned it on and move the z-axis up clear from the shipping block.

    I took the assembly apart and noticed that the cam inside it was bent and even with it off and everything disconnected (just the cam in the block between the two bearings), it wouldn't spin freely. John was nice enough to have a new cam, bearings, brass bushing, and clips sent to me. Assembled everything today, cam spins freely, attached arm. Went through the drawbar tightening procedure: Tighten it all the way, back it off 1 turn. Tighten the collar all the way down and then back it off 1 turn. Then I installed the LDB assembly on the tool. First pull is very "sticky" again, and it sounds like something is slipping. Took the LDB assembly apart again and noticed that the cam shaft is again bent, and the brass bushing has a flat on it (same problems I had with the original).

    Does anyone have a Pulsar with an LDB? Do you have problems with it? I'm actually super disappointed... the LDB was one of the reasons I went with Novakon over other brands (I don't have shop air where I am). I'm thinking that maybe it's just a bad design and very poorly machined - I mean the fit and finish of the Pulsar in general leaves some to be desired, but the machining on the LDB seems super sloppy.

    In any case, I took the entire LDB assembly off the tool, just to check if anything was wrong with that. I can't really see anything obvious wrong though. I did take a video looking up through the spindle assembly, and while the taper doesn't obviously look to have excess runout (don't have a dial indicator yet... I know, I need one, I'm very new to owning a mill. It's the first thing I'm going to buy when I get this damn thing finally set up), the bore where the drawbar sits seems to very noticeably wobble. Here's the link to the video ( ) - It was taken with my phone on a block pointed up through the spindle with the tool set to 100 rpm. Does that look normal? This drawbar problem has me wondering what other problems I might encounter with this tool.

    Anyway, thanks for any/all your help.
    Mine never really worked right. The design isn’t robust enough although a good idea in theory. Save yourself a headache and spend a day building a power drawbar. I posted the cad files and it was the best upgrade besides pathpilot I did to my pulsar.

    Less ideal is removing the LDB and using a cordless impact wrench to tighten the drawbar if you don’t have air. I did that while building the power draw bar and it wasn’t too bad as the servo spindle provides enough resistance so u don’t need extra counter pressure



  5. #5
    Member
    Join Date
    Jan 2016
    Posts
    386
    Downloads
    0
    Uploads
    0

    Default Re: Pulsar problems

    I followed Brian's advice and made a power draw bar using his cad files. I upgraded to PathPilot when I first got my Pulsar. Really happy with both my PDB and PathPilot.



  6. #6
    Registered
    Join Date
    May 2017
    Location
    United States
    Posts
    18
    Downloads
    0
    Uploads
    0

    Default Re: Pulsar problems

    Right, I get that the PDBs out there are better than the LDBs. My worry now is the drawbar "rubbing" issue I'm describing. Look at the upper bore of the spindle in the original video, it's way off center. If you put an R8 collet in the bottom of the spindle, the drawbar is going to have to come down at an angle to be able to thread into it, and that's going to cause it to bind against the upper part - especially when everything is torqued down.

    Here's a video of the drawbar being pulled in and out with the washers removed and it just being threaded into an R8 collet. You can hear the ridges of the drawbar rubbing on the upper bore of the spindle.

    Even if I make a power drawbar I'd like to resolve this issue. That is, unless they're all like this. Can anyone comment on that?

    Here's the video:





  7. #7
    Member
    Join Date
    Feb 2006
    Location
    USA
    Posts
    7063
    Downloads
    0
    Uploads
    0

    Default Re: Pulsar problems

    You're chasing non-problems. The drawbar is a roughly 12" long 7/16" bolt. All things considered, it is quite flexible. A mis-alignment, even if actually present, will have NO effect on the LDB operation. The bottom end of the drawbar is centered by the collet, NOT by the spindle. The drawbar head is centered to the spindle by its shoulder, which is a close fit to the upper spindle bore.

    Regards,
    Ray L.



  8. #8
    Member
    Join Date
    Aug 2007
    Location
    usa
    Posts
    701
    Downloads
    0
    Uploads
    0

    Default Pulsar problems

    Weird. Take off that upper plate and look. There should be a large keyed pulley and the top of the spindle assembly

    Also my spindle was way off center such that the ldb would rub on the side and even loosen up the drawbar such that the tool would slide out



  9. #9
    Registered
    Join Date
    May 2017
    Location
    United States
    Posts
    18
    Downloads
    0
    Uploads
    0

    Default Re: Pulsar problems

    I called Novakon and they're going to take care of it. John said that was way too much eccentricity in the upper part of the spindle. Glad he was so responsive.

    I would have to disagree that it's a non-problem. The sound I'm hearing in that video is just a quieter version of the sound I'm hearing with everything torqued down when I pull on the LDB - and I had to torque everything down really really tight to get the washers to compress. I bet more than 50 ft-lbs, which John said was higher than he would have expected. So I am relatively certain that rubbing is causing my problem.

    On another front though - I did go ahead and buy PathPilot from Tormach and I may as well do that upgrade while I'm waiting for new parts. I don't plan on being able to switch back and forth between Mach3 and PathPilot, so I think I'll just ghost the drive that came with my tool onto a portable drive (just for backup) and use the SSD that's on the tool for the install. The computer MB that's in my tool only has a PCI-e slot. Does that mean I should by the 6i25 card from Mesa instead of the 5i25 card? Will the settings that you posted be the same for the 6i25 as the 5i25?



  10. #10
    Member
    Join Date
    Aug 2007
    Location
    usa
    Posts
    701
    Downloads
    0
    Uploads
    0

    Default Re: Pulsar problems

    yeah 6i25 for pci-e
    same settings

    glad john is taking care of things



  11. #11
    Member
    Join Date
    Dec 2009
    Location
    USA
    Posts
    594
    Downloads
    0
    Uploads
    0

    Default Re: Pulsar problems

    I have been very happy with PP since my NM200 conversion. I'm much more confident about leaving the mill while it's running a long job than I was with Mach.



Tags for this Thread

Posting Permissions

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


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

Pulsar problems

Pulsar problems