Page 2 of 4 FirstFirst 1234 LastLast
Results 11 to 20 of 37

Thread: Oval Drill holes

  1. #11

    Default

    If I remember correctly, when I had my gear issue, I could feel the gear slop when trying to move the belts by hand.
    The 50-50-90 rule: Anytime you have a 50-50 chance of getting something right, there's a 90% probability you'll get it wrong.

    Do it on a Mac.
    Vietnam Vet '65-'66

  2. #12
    Join Date
    Feb 2007
    Location
    Palo Alto, CA
    Posts
    110

    Default I hate to sound like a broken record, but...

    ...the traction belts feel solid as does the z-truck. That's why I thought perhaps something was bent within the z-truck assembly. I understand the objections to that theorey (the overall sloppiness of the holes, the variability of the direction of the ovals, etc.), but perhaps the theorey needs a little refinement. What if in stead of being bent, something has become "soft". That is, assuming that within the chuck assembly, there are rings and/or washers of a compressible material (say vinyl or silicon or something). Let's say that during the unpleasantness with the stuck bit, one side of chuck's internal cavities became so compressed that the materials within became permanently deformed. The washer or ring or whatever get's shifted around during normal low-speed operations, like bit insertion/removal, which accounts for the variable oval direction. Once the bit is in high speed operation, the centrifugal effects tend to lodge the abnormal geometry into a single orientation, creating a single axis of rotation out of alignment with the basic z-axis. The bottom line to this theorey is simple: get a new quick-release assembly from CW (and not from Sears as I've been warned on numerous occasions). This I know to be a home-repair type service, since there's a PDF on the procedure. Probably wishful-thinking on my part, but I AM pretty sure my x-axis gears and z-truck are currently fairly solid.

  3. Default

    I don't recall the oval hole problem coming up since it was fixed with updated software. Be sure you are running the latest software version. If I recall correctly, with the fix, if you are making 1/8" holes with a 1/8" bit the x and y axis should not move while the hole is being drilled. I haven't done any hole drilling since the fix. There are some using the hole feature for drilling shelf pin holes. Maybe one of them could verify the x and y axis should not move when drilling a hole that matches the dia. of the bit.

  4. #14
    Join Date
    Mar 2007
    Location
    Ohio
    Posts
    1,109

    Default

    Need to watch the belts to see if it is moving... that would verify what John is saying... if they are, but yet they are solid while the machine is at idle, then the software is moving the part. If so, again, sounds like a malfunction. are you running the latest software?...

    I am going to run some holes tonight to see what i get... you really have me curious on this. I didnt go to the latest rev yet... I am running 1.119


    Ron
    To order the "Made in USA" Rock Chuck, and other custom tools and accessories I make for your CarveWright, see my website by clicking here -> http://www.cw-parts.com
    See a quick video of the new Rock Chuck in action here!
    Read up on QC Removal for stubborn chucks here
    See the Rock install video here
    You can also visit here for discussion content.
    Email me by clicking here

  5. #15
    Join Date
    Feb 2007
    Location
    Palo Alto, CA
    Posts
    110

    Default Software is the latest.

    I'm running 1.120. There was definitely "pecking" and moving during the drilling. I just calibrated the machine, and I'm literally in the middle of rerunning a drill test. I'll see if that helps.

    cycollins

  6. #16
    Join Date
    Jan 2007
    Location
    NE PA USA
    Posts
    9,983

    Default Try this

    Another test I would do is design a + on a board and make the holes 1/8 inch in the center and one step away in every direction. Then step it up in size for another set then back to 1/8 inch and see what you get.

    AL

    Try this file on a scrap board.
    Last edited by Digitalwoodshop; 07-01-2007 at 08:55 PM.

  7. #17
    Join Date
    Jan 2007
    Location
    Greensboro, NC
    Posts
    265

    Default

    Quote Originally Posted by rjustice View Post
    It has been mentioned that the cutter diameter to length ratio on the 1/8" bit is a little long, perhaps the bit just doesnt have enough rigidity to stay straight, and starts wandering
    A solid carbide bit will not flex enough for this result without snapping first so I doubt it is caused by that. However, a loose spindle could allow the bit to follow tough grain.
    Charles M

  8. #18
    Join Date
    Feb 2007
    Location
    Palo Alto, CA
    Posts
    110

    Default

    Thanks to Digitalworkshop for the "+" idea. I might actually use that instead of a drill hole, since the idea of the drill hole was simply to get a precise location fix that I could use for a drill press to punch through to the other side (my projects are always more than an inch in thickness and the CW won't drill through.

    I agree with with what Charles M said about the carbide drill. That's why I thought perhaps the QuickRelease mechanism was loose in terms of its alignment with the z-truck and might need replacing. There are also fixtures on the z-truck to which the quick-release attach and these also might be bent or wobbly. I have a profound aversion to the idea of sending the unit back to Texas for service, but I suppose it could be necessary or at least desirable.

    cycollins

  9. #19
    Join Date
    Mar 2007
    Location
    Ohio
    Posts
    1,109

    Default

    Between the chuck, the bearings, and the bit, I think it is possible to get a lead off condition... I have seen it happen in steel.. In theory i think you are correct "carbide doesnt flex"... but again with all the variables I have seen this happen

    Ron

    Quote Originally Posted by Charles M View Post
    A solid carbide bit will not flex enough for this result without snapping first so I doubt it is caused by that. However, a loose spindle could allow the bit to follow tough grain.
    To order the "Made in USA" Rock Chuck, and other custom tools and accessories I make for your CarveWright, see my website by clicking here -> http://www.cw-parts.com
    See a quick video of the new Rock Chuck in action here!
    Read up on QC Removal for stubborn chucks here
    See the Rock install video here
    You can also visit here for discussion content.
    Email me by clicking here

  10. #20
    Join Date
    Feb 2007
    Location
    Palo Alto, CA
    Posts
    110

    Default Really confused

    I did another test recently and got very confusing results. I routed a rectangular path that was a little over 10" in length by a little over 4" in width. It used the 1/8" cutting bit and was 1/8" wide and 1/8" deep. It worked pretty well. The lengthwise spans of the rectangle were only slightly wider than 1/8" (~.381"). The width-wise spans were only slightly fatter (~.401"). With all the problems I was having with drill holes I was expecting much worse (although I suppose it is a ~10% difference). Anyway, I could repeat this project over and over and the results were very consistent. The drill holes on the other hand were a bit random. Finally, I overlayed a project with 1/8" drill holes at the corners. Same peculiar hole behaviors.

    Then, I did a much more compact project. Precisely 6" by 4" with the same kind of routed lines and drill holes at the corner. I added some more routed lines in a circle and some crosses and a diagonal line. All the endpoints were on a .25" grid. This time, the horizontal and diagonal lines were very similar in size and (and this is the wierd part) the drill holes were pretty circular, so much so that I have trouble seeing the eliptical shape with the unaided eye. So what's the rule here? Put things on nice rational boundaries and get more precise behavior? Wierd. Maybe it was the scale of the project. I don't know. Maybe I don't need to know. I only use drill holes for reference marks (and maybe ultimately for peg holes on a sled). As long as there IS a way to get good holes, maybe I don't care. No, it's not true. This kind of thing drives me nuts. I need some sense to using this tool or I'll never feel like I can control it. Heavy sigh.

    Cycollins

Page 2 of 4 FirstFirst 1234 LastLast

Posting Permissions

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