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  1. #21
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    Quote Originally Posted by gregormarwick View Post
    Box ways are not the deal breaker some make them out to be, that impression is really a legacy of the early generations of linear guide machines (or plain cheap machines) that use ball guides. Modern roller guide machines are just as capable of heavy cuts as box way machines.

    Another aspect of the spindle that's counterintuitive - for heavy milling with carbide insert tools, you really don't want a gearbox. The backlash in the geartrain creates torque "bounce" under load that is hard on carbide. It has been my experience that the life of carbide inserts when roughing of steel is significantly better with a direct driven, or best of all integrated motor spindle. You'll lose torque for big tools, but if you can live without 6"+ facemills and huge boring heads and massive taps etc, it's a worthwhile tradeoff IMO.
    I had also wondered about the gearbox.

    What about belt driven spindles? I assume that also is less than great with carbide tools? That rubber must cause some bounce.......no?

  2. #22
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    Quote Originally Posted by cj133 View Post
    Thank you for responding.

    This may be a stupid question but, it seems like a lot of machines don't list what taper they have?

    For example, there's a used SNK FSP-80V local to us. It looks like a large machine, but no mention of what spindle it has, not even on SNK's website. I just noticed the same thing with Okuma, none of them mention what taper they have.

    I was concerned about HAAS not being rigid enough, especially since they seem to use both 40 and 50 taper in the same machines.
    You may just have to call or email to confirm. If the machine looks like it meets your needs, try to get a sample cut done to confirm operation and to check for extraneous noise or other gotchas.

    One thing to be certain of is the lubrication system - are all axis and ballscrews being lubed correctly, and is there any excessive wear? Lots of threads here on doing on-site inspection of machines.

  3. #23
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    Quote Originally Posted by cj133 View Post
    I had also wondered about the gearbox.

    What about belt driven spindles? I assume that also is less than great with carbide tools? That rubber must cause some bounce.......no?
    No im in the belt is fine, its the actual slop in the gears that can cause the issue, if anything the slight stretch in belts could be argued is a benefit. I too would not chose Hass for this kinda stuff. That said the gear drive is not total issue, you just need to keep inserts in the cut and plan your radial engagements and cutter paths such as to achieve this as much as possible.

    Roller or plane ways is akin to large breasts or Big butts in women, both so long as there big enough generally work just fine in both species!

    If you want to do these kinda cuts in thoes kinda metals like your current mill cuts aluminium then i would be looking at the smaller 50 taper gantry mills or a horizontal, a VMC is not the correct machine geometry for really letting rip with high cutting forces like your describing.

    One thing your seriously going to have to consider is just how you plan to hold the parts. Small parts like these won't work in vices all that well for the kinda cuts your describing. I doubt your moving stuff in std 6" Kurts with your current 7.5hp, when you get upto a cutter doing 3" deep in steel with 30+hp trust me, its hard to hold onto small stuff hard enough! Cutting forces with large inserted cutters can be multiple tons, that needs some serious grip to keep things still.

  4. #24
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    Quote Originally Posted by cj133 View Post
    As far as repairs, I think we can handle most of them.
    My biggest concern I think, is getting a control that has the most post processor support. I seems like Fanuc is where its at when it comes to that, but at the same time floppy disks are a pain........





    I'm sorry, I keep forgetting how big this forum is. I'm used to smaller places where there's a good chance everyone has seen every post.

    Our current machine, is a South Western FHM7, which apparently was a machine actually made by some company called King Richard.
    It's a tiny 7.5HP machine with a 40 taper spindle, but I've been told by a few the machine isn't near big enough for the spindle. I get the impression it doesn't even qualify for the "toy" category.


    We often need to mill mild steel plates that are 3" thick using a 1" x 4" endmill. If a good 40 taper machine can do this with light passes that would get the job done. Our current machine, even trying to take a 2" axial cut and only 0.005" radial will cause chatter. The problem being, I want a nice finish pass and doing stepped passes stinks.

    What I would like, is to be able to mill 3" deep and take a pretty heavy cut using a corn cob, I'm assuming that's something we would want a 50 taper for?


    Is there a general rule on how big of a tool you should use with a good 40 taper machine?
    That sounds like 50 taper to me.




    ---------

    Does SNK make ANYTHING smaller than 50 taper?



    I for one like geared heads, but his point me be valid. Never heard of such concern before.
    Would like to see some tests on that sometime...
    On a Bridgeport - ABSOLUTELY!
    On my Cinci 630 - I'm a bit skeptical ....
    You're generally in high gear when milling anyhow, so the only lash would be in splines - unless there is a clutch set-up, then there may not be any lash at all.



    I wouldn't think that you'd have much trouble finding a tech in Jersey.
    It's not Nebraska, or New Mexico...




    For heavy pocketing, a horizontal is great!
    Not so great for tossing a plate up on the table and clamping it down and being off to the races as quickly...

    -------------------

    Think Snow Eh!
    Ox

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    Quote Originally Posted by Ox View Post
    That sounds like 50 taper to me.




    ---------

    Does SNK make ANYTHING smaller than 50 taper?



    I for one like geared heads, but his point me be valid. Never heard of such concern before.
    Would like to see some tests on that sometime...
    On a Bridgeport - ABSOLUTELY!
    On my Cinci 630 - I'm a bit skeptical ....
    You're generally in high gear when milling anyhow, so the only lash would be in splines - unless there is a clutch set-up, then there may not be any lash at all.



    I wouldn't think that you'd have much trouble finding a tech in Jersey.
    It's not Nebraska, or New Mexico...




    For heavy pocketing, a horizontal is great!
    Not so great for tossing a plate up on the table and clamping it down and being off to the races as quickly...

    -------------------

    Think Snow Eh!
    Ox
    Is SNK considered a good solid machine? The pivoting head seems concerning no? I'd absolutely love a 5th axis machine.

  6. #26
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    AFAIK they are OK.
    They are much more into boring mills than commodity sized mills from what I've seen.

    I'm not sure that I have ever seen a vertical SNK?


    ---------------------

    Think Snow Eh!
    Ox

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    Quote Originally Posted by Ox View Post
    I for one like geared heads, but his point me be valid. Never heard of such concern before.
    Would like to see some tests on that sometime...
    On a Bridgeport - ABSOLUTELY!
    On my Cinci 630 - I'm a bit skeptical ....
    You're generally in high gear when milling anyhow, so the only lash would be in splines - unless there is a clutch set-up, then there may not be any lash at all.
    There is always lash in a gear train. It may be minute, but it's always there. If you can maintain a positive torque at the cutter, it's all good (like 100% engagement on a facemill), also usually not much of an issue with a solid cutter because there is never much torque being applied. But profiling around the edge with a large shoulder mill or porcupine cutter for example, where there is massive instantaneous torque spikes and instantaneous torque drop outs, will make the gears rattle. Try profiling around the edge of a plate with a feed mill on a geared spindle for an extreme example.

    Belt driven spindles using heavy timing belts are fine IME.

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    Quote Originally Posted by cj133 View Post
    How does Okuma compare to HAAS?

    We were considering a HAAS VF-6/50 as a possibility. If it gets approved, of course.
    There is no comparison.
    In fact, Okuma and Haas should NEVER be uttered in the same sentence.

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    Quote Originally Posted by Generic Default View Post
    Mtndew, are you sure about that M560 special? I just got a quote on it a month ago, it was 132k with probes and conveyor. If it's down to 100k now I need to get one. Is that dealer specific?
    Not sure if it was dealer specific to be honest. But that was also without the probes which add, what... 10k? 15k?
    And the conveyor adds around 10k as well.
    We're getting a new Genos 400 lathe for 80k, WITH conveyor, tool setter, Advanced One Touch, the works. That is a hell of a deal that we couldn't pass up.

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    Oh how I'd love a conveyor.....................

    Probes I could do without though.

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    Quote Originally Posted by cj133 View Post
    An example of some of our jobs is we often have to clean up hot rolled steel plates. Off the top of my head, I believe they're 18" x 12" x 3". We mill the ends and face the top and bottom. It's a long, slow process on the current machine.

    Currently milling 1.5" diameter holes into 4" x 4" x 18" 316SS blocks. After that, hollowing out 7"x7"x2" chunks of ASTM A572-50.

    We do some aluminum,and some small parts, but mostly steel and stainless steel from larger stock.

    Waiting to hear back regarding budget. My guess, $60-80K for used.
    From your description, I'd look into a horizontal. Horizontals kick ass over verticals for that kind of work. They are more limited in size but everything else about them is way better.

    At that price you could find a decent Makino, Mazak, Okuma or Mori. No problem with posts.

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  14. #32
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    Quote Originally Posted by cj133 View Post
    Oh how I'd love a conveyor.....................
    Conveyors are a must have if you're doing any kind of work where you're making chips.
    Shoveling out the bucket isn't making you money.

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    IMO conveyors are nice if you are running production. For small runs, I'd rather to invest the money in probing / tool setting.

    $10K - 15K for probes is insane...

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    Quote Originally Posted by riabma77 View Post
    IMO conveyors are nice if you are running production. For small runs, I'd rather to invest the money in probing / tool setting.
    I guess if your parts are able to be held in the palm of your hand before and after machining, then yes, you probably can hold off on a conveyor.
    We do 1-2pcs jobs to 1,000 pc jobs. Some of our 1-2 pc jobs will fill up two or three 55gallon cans of chips.

    Probes are awesome to have,I love em. But I view them as a luxury.

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    Quote Originally Posted by Mtndew View Post
    I guess if your parts are able to be held in the palm of your hand before and after machining, then yes, you probably can hold off on a conveyor.
    We do 1-2pcs jobs to 1,000 pc jobs. Some of our 1-2 pc jobs will fill up two or three 55gallon cans of chips.

    Probes are awesome to have,I love em. But I view them as a luxury.


    That's the issue I have.
    The larger stuff, even a few piece run produces a disgusting amount of chips. One of the best things I ever did was switching to AlTiN coated carbide and going dry on steel. At least now the heavy mountains aren't all sticky.

    I owe many thanks to those on here that told me to stop using coolant when milling steel. Right now I'm doing 316 dry, I know some say it's a bad idea but I'm having good results. Just plenty of air to get rid of the chips.

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