Old criterion vs new precision import boring heads
Close
Login to Your Account
Page 1 of 2 12 LastLast
Results 1 to 20 of 24
  1. #1
    Join Date
    Apr 2017
    Country
    UNITED STATES
    State/Province
    Michigan
    Posts
    17
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    10

    Default Old criterion vs new precision import boring heads

    Hello guys, I'm looking for some real world experience. I recently purchased a 1996 BP VMC1000 that came with a ton of tooling but no boring head. I run a small shop producing automotive performance parts, not space shuttle parts. I've only ever used the criterion .001" boring heads that I'm pretty sure every machine shop owns (including myself). It works well enough in my cincy toolmaster with indexable bars, but I have definitely opened a few bores up more than .001" when the dial was turned one division. Barring my past experience, I'm thinking that a precision adjust boring head might be a better match for the cnc even though I don't need to chase tenths every day like many here.

    There are a few parts I'm planning that will require .75"-1.5" diameter holes about 1.25" deep in aluminum and durabar. Quantity will be maybe a few hundred a year and tolerances of +/- .0005" is more than enough.

    So that brings me to the question of has anyone actually used one of the import precision boring head sets like this Precision Boring Facing Head .0002" fine machining 8mm-201mm (0.315"-7.9") Comb | eBay Obviously its Chinese, but it looks to be significantly above harbor freight level Chinesium. Naturally all the inserts it comes with will strictly be used on test pieces and Sandvik/iscar/kennemetal inserts used for parts. I've looked at other boring sets (such as the nice maritool package), but they're all $1.5k+ and just can't be justified at the current moment. Maybe in a year or two, but the machine needs to actually make some parts and get out of the money pit stage haha. I have a spare long 3/4" straight shank criterion head that I could chuck up in a holder and use in the cnc, but I'm expecting that will end up fighting me to hold any kind of repeating.

    Thanks for any real world feedback!

  2. #2
    Join Date
    Nov 2014
    Country
    UNITED STATES
    State/Province
    Florida
    Posts
    3,341
    Post Thanks / Like
    Likes (Given)
    1463
    Likes (Received)
    1581

    Default

    I don't see any real vernier scale that, IMO, would make it any better than your .001" increments you are doing now.

    https://www.techniksusa.com/download...cat_boring.pdf

    About half way thru you can see a picture of the vernier scales. I've used this particular brand and they work very well, out of your price range, but maybe something to consider for later....

  3. #3
    Join Date
    Apr 2017
    Country
    UNITED STATES
    State/Province
    Michigan
    Posts
    17
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    10

    Default

    Quote Originally Posted by Mike1974 View Post
    I don't see any real vernier scale that, IMO, would make it any better than your .001" increments you are doing now.

    https://www.techniksusa.com/download...cat_boring.pdf

    About half way thru you can see a picture of the vernier scales. I've used this particular brand and they work very well, out of your price range, but maybe something to consider for later....
    I emailed the seller asking for a close up of the scale and it is marked in .005mm increments. Sorry, forgot to mention that earlier.



    I drooled over the techniks catalog also, the bohrstar 100 setup would certainly be nice. Sadly it's just not justifiable at the exact second. I just need something to bore a few hundred holes reasonably precisely and make some money. Then I can buy some nice techniks/mari/D'Angelo/etc.

  4. #4
    Join Date
    Oct 2013
    Location
    New Jersey
    Posts
    1,045
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    880

    Default

    I did some boring with a Criterion boring head on CNC and couldn’t hold tolerance hole to hole without sneaking up on it taking a lot of time. Then we got a job with 100 bored holes the same size. A $600 Sandvik with the tri-lobe shank absolutely killed it. Hole after hole right on the money. Worth every penny, we’d have lost our ass on that job without it.

  5. Likes Mtndew, AlfaGTA liked this post
  6. #5
    Join Date
    Apr 2004
    Location
    Milwaukee,WI
    Posts
    1,262
    Post Thanks / Like
    Likes (Given)
    6916
    Likes (Received)
    988

    Default

    The ebay boring head shows units sold. Click on the link and it shows one was purchased March 11. Try messaging the buyer and ask him how he likes it.

  7. Likes primeholy liked this post
  8. #6
    Join Date
    Feb 2008
    Location
    MI, USA
    Posts
    766
    Post Thanks / Like
    Likes (Given)
    57
    Likes (Received)
    288

    Default

    If you only have a couple hole size ranges (say around .75 and around 1.25), I'd get individual boring heads from a good company. We tend to have mostly Parlec heads. .0001 adjustment, short tool length (with modular extensions as needed).

    I hate the type of boring setup you have. Sure, I don't have that one, but of the ones we do have, ours look the same but have .001 or maybe .0005" adjustment (or their metric equivalents.)

    They are too long. Too far from the spindle face. The bars you put in em for smaller holes are also too long.

    Will it work? probably. Is it cheap? yeah, that looks pretty cheap. But it is chinese.

    I'd be wary of how much the thing moves when tightening the lock screw after adjustment. I'd be even more wary on the quality of the taper. Nothing worse than chasing tenths when fighting a tool holder that clamps differently every time you change tools.

    I'd say look on ebay for the couple sizes you need for good names. Doesn't sound like you need the range all the way up to 200mm. You might spend a couple hundred dollars more than the 500$ Chinese POS, but I think you'd be happier. At the very least, you won't have to find out that you bought that for 500 but still need a good one to get you through.

    Also note: the one you linked ships from Australia, and you don't appear to be from there. But you probably know that.

  9. Likes primeholy, Mike1974, AlfaGTA liked this post
  10. #7
    Join Date
    Nov 2014
    Country
    UNITED STATES
    State/Province
    Florida
    Posts
    3,341
    Post Thanks / Like
    Likes (Given)
    1463
    Likes (Received)
    1581

    Default

    I was going to suggest trying Dvlieg(?) similar to what the last guy said about buying individual small range units. I know (or it was my impression until looking) Dvlieg might be seen as "old school" with the brazed carbide inserts, but on larger sizes they sell cartridges that will accept carbide inserts. Also, like what I linked with the Bohrstar, I think those kits are like $2000 maybe. Yes, alot of money, but it will do a large range of sizes, and there will be no buyers remorse, especially if you buy the china set and struggle to maintain size....

  11. Likes Dan from Oakland, mmurray70 liked this post
  12. #8
    Join Date
    Apr 2018
    Country
    UNITED KINGDOM
    Posts
    1,684
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    777

    Default

    Quote Originally Posted by Mike1974 View Post
    I was going to suggest trying Dvlieg(?) ...
    <aol mode> me, too !</aol mode>

    The microbore inserts have better balance, hold size better, cost less than anything else. And you can make your own bars for special situations. Except for the limited range of adjustment, you can't beat 'em.

    if you search, there's an 'e' in there - Devlieg

  13. #9
    Join Date
    Dec 2015
    Country
    UNITED STATES
    State/Province
    Illinois
    Posts
    382
    Post Thanks / Like
    Likes (Given)
    123
    Likes (Received)
    213

    Default

    Since no one mentioned it.

    I'm sure you are aware but with a boring head, or really any other tool, if you take a pass that removes, say .100 from a bore then move the tool to try and take .001 more you will cut significantly more than the .001 you wanted to due to the tool deflecting on the heavier cut and springing back on the lighter cut.

    Sorry if you were aware of this machining 101 concept, but I'm not really sure who I'm talking too.

  14. Likes moonlight machine, Ox, Ray Behner liked this post
  15. #10
    Join Date
    Mar 2009
    Country
    UNITED STATES
    State/Province
    California
    Posts
    4,868
    Post Thanks / Like
    Likes (Given)
    89
    Likes (Received)
    900

    Default

    Quote Originally Posted by converterking View Post
    The ebay boring head shows units sold. Click on the link and it shows one was purchased March 11. Try messaging the buyer and ask him how he likes it.
    Probably was their director of sales.

    I own a Criterion and have used it with a boring bar set made in India. Found out what is worst than ChiComm made.

  16. #11
    Join Date
    Feb 2004
    Location
    Staten Island NewYork USA
    Posts
    3,668
    Post Thanks / Like
    Likes (Given)
    1068
    Likes (Received)
    1744

    Default

    I was in a similar boat trying to chase a couple tenths with the ol Critter. Once I dialed it in, made a few parts the boring head did run consistent and able to hold a couple tenths for quite a few parts...till tool wore a little then it was back to getting it dialed in again...a real pain.

    I did the same look and heart attack when getting pricing back...I think Big Kaiser was in the 4K range with one package. I was about to pull the trigger on the Mari holder but my local Used Tool dealer came through with an older Erickson tenth-set boring head.
    I have to say its is a whole lot nicer to have accurate adjustments in large "one" 10th increments. No more trying to subdivide minuscule spaces between marks by eye and hoping.

  17. #12
    Join Date
    Apr 2004
    Location
    Milwaukee,WI
    Posts
    1,262
    Post Thanks / Like
    Likes (Given)
    6916
    Likes (Received)
    988

    Default

    The Big Kaiser digitals sure look nice and are probably a pleasure to use. I use several Komets that aren't too bad.

  18. #13
    Join Date
    Feb 2007
    Location
    Aberdeen, UK
    Posts
    3,439
    Post Thanks / Like
    Likes (Given)
    1205
    Likes (Received)
    1278

    Default

    Quote Originally Posted by SIM View Post
    I was in a similar boat trying to chase a couple tenths with the ol Critter. Once I dialed it in, made a few parts the boring head did run consistent and able to hold a couple tenths for quite a few parts...till tool wore a little then it was back to getting it dialed in again...a real pain.

    I did the same look and heart attack when getting pricing back...I think Big Kaiser was in the 4K range with one package. I was about to pull the trigger on the Mari holder but my local Used Tool dealer came through with an older Erickson tenth-set boring head.
    I have to say its is a whole lot nicer to have accurate adjustments in large "one" 10th increments. No more trying to subdivide minuscule spaces between marks by eye and hoping.
    The old tenth-set heads are a big step up from the basic criterion type heads, and a solid option if your budget can't stretch to newer precision heads.

    I swear by D'Andrea TRM heads, also available from Iscar under their ITS-Bore brand.

  19. #14
    Join Date
    May 2002
    Location
    South Central PA
    Posts
    13,422
    Post Thanks / Like
    Likes (Given)
    2159
    Likes (Received)
    3343

    Default

    For the small bores look at Devlieg or universal micro-set bars. For your larger bores, gather up some valenite Vari-set bars and heads. There are 2 basic styles, one for rough boring and one for fine boring with micro set adjustment that resembles DeVlieg micro set. The Valenite bars have a coarse adjustment on a dovetail to allow one bar to cover a lot of range plus a micro set head that is spring loaded so you don't have to loosen and tighten anything else beside the adjustment. Plus most are equipped to use carbide inserts so if you wear one out you change the insert, readjust and drive on. The Devlieg bars all have brazed carbide so you'll need a way to grind and dress the carbide. Both are available pretty cheap from ebay and used tool dealers, watch for large collections of random tools that sell for ~$10-$20 per piece or so. I've been hoarding this stuff for years and have 25 or more bars permanently set up in holders so I can grab one out of the rack when we rerun a part, plus crates of others to draw from and I have less invested in all of it than a new precision fits everything setup.

    I do have a Pinzbohr 54 kit and it's awesome for single or small quantities where I don't have a tool ready, but I'm reluctant to use it for production just because it's so expensive and delicate and has so many pieces to lose. Have D'Andrea stuff too, it's all pretty nice stuff. But 95% of weekly operation is done with the Vari set tools. Also watch for Komet, Kaiser Kennametal Sandvik Erickson and Parlec and other heads and bars coming up for sale, just do a little research so you don't end up with a lot of hardware that you can't fit together and put in your machine.

  20. #15
    Join Date
    Nov 2004
    Location
    RC, CA
    Posts
    1,963
    Post Thanks / Like
    Likes (Given)
    211
    Likes (Received)
    371

    Default

    I'll put in a plug for the kit Mari sells. Rock solid, and repeats better than I could measure dialing between rough and finish passes on multiple parts.

    The metric calibration takes a bit of getting used to, as does the number of turns on the dial for a decent DOC.

  21. #16
    Join Date
    Apr 2019
    Country
    CANADA
    State/Province
    Alberta
    Posts
    13
    Post Thanks / Like
    Likes (Given)
    2
    Likes (Received)
    3

    Default

    Over the years I was using quite a number of boring heads; many makes in many sizes. All will produce consistent bores once adjusted and locked, the big difference is the quality and accuracy of adjustment and the time and effort to get the right setting. I have had good experience with the Moore boring heads as well as the Devlieg Microbore on the Moore jig borers. Large Criterion boring head (S3) on a big mill worked very well for larger bores and was easy to set, same is true as well as the smaller Criterion square heads.
    My favourite I am still using for ~1" and larger bores is the TREE boring head. With the slide set at an angle one can get extremely fine diameter adjustment and the large ring makes setting very easy.
    75"-1.5" diameter holes about 1.25" deep in aluminum is certainly not a big challenge and a decent used Criterion boring head will do the job nicely.

  22. #17
    Join Date
    Jan 2007
    Location
    Flushing/Flint, Michigan
    Posts
    7,504
    Post Thanks / Like
    Likes (Given)
    371
    Likes (Received)
    6280

    Default

    Quote Originally Posted by matra View Post
    ..... With the slide set at an angle one can get extremely fine diameter adjustment ...
    I think many miss the fact that the tool tip does not need to inline with the slide and just use a standard setup on boring heads.
    Doing so ruins the calibration on the screw but you make very small diameter moves with ease.
    Way off and you can get 10:1 but your bar has to be close to right size as you have little room to move.
    I do like or should say love the old Devlieg cartridge style but a tad of wear in the key makes nailing that last few tenths frustrating and you can't do this trick with this design.
    Bob

  23. #18
    Join Date
    Nov 2004
    Location
    RC, CA
    Posts
    1,963
    Post Thanks / Like
    Likes (Given)
    211
    Likes (Received)
    371

    Default

    Some of the criterion heads I've used don't have the bore for the bar on centerline, and if you install them so the dial reads normal they drag on the heel.

    Really just a problem with small bars. So you either rotate them a bit CCW for clearance, or put them in backwards.

  24. #19
    Join Date
    Dec 2015
    Country
    UNITED STATES
    State/Province
    Connecticut
    Posts
    754
    Post Thanks / Like
    Likes (Given)
    22
    Likes (Received)
    229

    Default

    Are there just a couple different size holes in that range ? Are reamers an option?


    Sent from my iPhone using Tapatalk Pro

  25. #20
    Join Date
    Sep 2011
    Country
    UNITED STATES
    State/Province
    Virginia
    Posts
    25,745
    Post Thanks / Like
    Likes (Given)
    7561
    Likes (Received)
    8122

    Default

    Quote Originally Posted by ripperj View Post
    Are there just a couple different size holes in that range ? Are reamers an option?
    .. or roller burnishing for the last ..nth?


Tags for this Thread

Bookmarks

Posting Permissions

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