Chads new machine

[turmite]

Chad is that spindle and Elti, E/C, or Colombo?

Mike

[chad]

None of the above. 

It is a HSD.

http://www.hsdusa.com/eng/home.htm

Chad

[chad]

Got a new dust collector today. I have cobbled together a test foot and skirt. So far so good, Need to change the foot mount and figure out how to suspend the hose.

Chad

[ynneb]

Great to see you are like me. In the excitement you slap it together just to see how well it works.
I never worked out a good hose suspension system. Lots of elastic straps sort of did the job.

[Manjeet]

Hi,

What a great job you have done. I have seen all the pictures. very nice machine. I request you please put some pictures of driving mechnism.

Thanks in advance

regard...Manjeey

[JerryFlyGuy]

Chad have you [or did/do you] ever had any vibration with that super long z axis? I've got a machine w/ a similar setup, only have ~24" on the Z  [which is a 6x6 .250 post] and I'm getting all kinds of vibrations from my spindle. I can't get it past ~9k rpm with a tool in it, before it starts vibrating the crapp outta everything.. [Which is no easy thing to do as my Gantry is a couple thousand pounds..] I'm thinking it has to do with harmonic's of my tube axis but I'm not entirely sure.. it could be my spindle, my tooling or my structure...

Curious..

Jerry

[chad]

I have never had any problems with "self resonance", in other words just running up to any spindle speed in free air. If you are having that problem I would suspect you have some sort of spindle balance problem. Try running it up with out any tooling in it and see if it does the same thing. If it does i would send the spindle back and have them re balance it. If it only does it with a tool in it, look for better tools.
Resonances are harmonics based if you get a bad one around 10k have you tried just pushing through it and going to 20k? also make sure your linear rails are solid and beefy and you have enough of a separation (on the yz mount) to make a sturdy z. There is no slop in my machine at all. I can grab the z and push in any direction with all i am worth and nothing clunks. I can flex things a couple of hundredths (my poor design in the y) but everything is tight.

If none of that helps then remember the old adage 'mass is your friend'.  I was having a problem with cutting at about 250 ipm .750 deep in mdf. This is I found was the about the right feed for what i was doing but I was getting a oscillation while cutting (slip stick). My solution was to add 4 25lb blocks of lead to the end just above the spindle mount inside of the z tube. This got rid of almost all of the problem.

Please start a thread with lots of pictures. I would love to see your machine. There are not many BIG mach machines that i have seen pictures of..

Chad

[JerryFlyGuy]

I've had it in just free air. I'm starting to think it's a spindle problem.. but I hope not... the month to get it repaired is just a bit too long.. I'm going to play with it a bit more tonight and see if I can identify where it comes and goes..  I guess approach it from no tool all the way through to full length tools and see what speeds and which tools excite it.  I've had the spindle up to 18k a couple times and in some cases it helped.. in others I couldn't turn in down fast enough..  I've also noticed that w/ a larger dia tool [2" facing cutter] that it seemed to help the problem.. I've got to play w/ it a bit more.. and get a better feel for it.. I've been so busy at work that I haven't had time and now I can't remember all the way's I had checked it etc.. 

BTW, if you want to see a vid.. there's one on youtube under my same profile name.. It show's the machine facing the bed. My mill [or so I call it] is 10 x 20 w/ ~24" Z... I'm wanting more but my garage has a low ceiling so.. for now.. it's gonna stay at 24..

I may get a thread going to show it off.... if I ever find a spare second
Thanks alot sir!
Jerry

[Chaoticone]

Yeah Jerry, start that thread. I wonder, if your Z tube is sealed, could you fill it with water, adding weight and dapening some of the bad res. ? Maybe even sand?

Brett

[JerryFlyGuy]

I will.. someday..  The tube is open at the bottom right now.. I've been toying w/ the idea of potting a second tube inside it w/ 80du urethane rubber [castable] and then if that doesn't kill it. adding lead or steel shot inside the inner tube.. I've got to do some testing first to figure out what is causing it and then attack it from there... it's only a 2.5hp but I should be able to take a 0.40" DOC x 1/4"SO cut at a couple hundred ipm w/ it.. I'd hope anyway..  I'll probably upgrade to a 7hp at some point but for now.. I gotta get this one working..

testing tomorrow..

Jerry