Page 4 of 7 FirstFirst ... 23456 ... LastLast
Results 31 to 40 of 65

Thread: Advice on drilling and tapping frames for optic mounts?

  1. #31
    Member
    Join Date
    Jun 2019
    Location
    out of here
    Quote Originally Posted by MistWolf View Post
    Go easy on the center punch. Center punching can create micro fractures which is why center punches are not allowed for use on aircraft structures.

    HSS drills are bad for drilling metal. Cobalt is good. Carbide is better than cobalt. Use split tip bits. They center and cut better.

    Use cutting fluid liberally.

    Don't rush. Make every move a conscious decision.

    Drill a little and back off to break the chip. Repeat.

    Tap a little and back off to break the chip. Repeat.

    Lightly chamfer the holes to deburr.
    Just ordered a few different carbide bits of different sizes up to 3.3mm.

    Enough people have recommended it that I should just start with that.

  2. #32
    Member
    Join Date
    Jun 2019
    Location
    out of here

    Getting ready

    @MickAK

    Name:  FF768572-D320-4514-B758-C1BEA6E9B300.jpg
Views: 179
Size:  28.4 KB

    Took the gun down to the frame for better access.

    Discovered that the existing holes match up to where the new holes are to be drilled.

    Name:  BA410467-0C15-4A98-9454-C84CD8F6FDC9.jpg
Views: 176
Size:  27.5 KB

    That might help with locating them perhaps.

    But I also have the 5 hole tap jig that looks like some of the holes line up.

    Name:  D96A1AEF-52B6-44DA-BEA5-4EA686799CBA.jpg
Views: 176
Size:  49.6 KB

    I can’t use that jig at face value because the 5 holes don’t go far enough away from the rails. But I might be able to use it to help me make straight starting punches if I flip and clamp this jig. I didn’t take a good picture but the holes are actually centered, lol.

    Or I might be able to use this jig to help me make a bar stock jig with properly spaced holes.

    But is that necessary with a drill press and clamps for the frame?

    I’m thinking light dimple with the punch, the label tape will actually keep the punch from sliding.

    Once I get the dimple, would a jig matter much for the drill press if I use cobalt or carbide bits?

  3. #33
    Member
    Join Date
    Jun 2019
    Location
    out of here
    Bought an automatic center punch to help reduce potential errors. Figure I can use it for car window glass breakers in the future.

  4. #34
    Member
    Join Date
    Jun 2019
    Location
    out of here
    I also have this for tracing circle targets.

    Name:  56C9B1AC-B94E-4C85-90D5-FC6AC41C7754.jpg
Views: 158
Size:  42.2 KB

    Name:  image.jpg
Views: 174
Size:  19.0 KB

    It’s fairly thick, but clear so I could find center.

    I could even order a few more to stack and make a jig, but not sure how necessary it is.

  5. #35
    Member
    Join Date
    Jun 2019
    Location
    out of here

    This is my mock up for punching

    Name:  8A504F32-4E55-4010-8E2F-621E8F398C96.jpg
Views: 178
Size:  69.0 KB

  6. #36
    Member
    Join Date
    Jun 2019
    Location
    out of here
    Name:  C7097059-0B77-48D7-9381-90D563535FD1.jpg
Views: 182
Size:  30.9 KB

    The place where I have to punch has embossed lettering. I’m concerned that the punch will slip off the letters.

    I silver sharpied the holes and letting it dry.

    Planning on Dremel grinding the letters flat so that the punch takes better.

    Good idea? Bad idea?

  7. #37
    Quote Originally Posted by JCN View Post
    Name:  C7097059-0B77-48D7-9381-90D563535FD1.jpg
Views: 182
Size:  30.9 KB

    The place where I have to punch has embossed lettering. I’m concerned that the punch will slip off the letters.

    I silver sharpied the holes and letting it dry.

    Planning on Dremel grinding the letters flat so that the punch takes better.

    Good idea? Bad idea?
    I think you would have a hard time dremeling it flat enough that the punch wouldn't slip in the convex surface created by the Dremel. I would be more concerned about the divot being on the border of the lettering and the drill bit walking off and snapping.

    It looks like your center might be just inside the U though, so you're probably good. You may find an automatic center punch to be more difficult than a hand one.

    Jigs are great for things that are either A: really, really important and you can't afford to mess them up or B: things you're going to be doing a lot of. The mount itself works as a pretty effective jig for this I think.

  8. #38
    Member
    Join Date
    Jun 2019
    Location
    out of here
    Quote Originally Posted by MickAK View Post
    I think you would have a hard time dremeling it flat enough that the punch wouldn't slip in the convex surface created by the Dremel. I would be more concerned about the divot being on the border of the lettering and the drill bit walking off and snapping.

    It looks like your center might be just inside the U though, so you're probably good. You may find an automatic center punch to be more difficult than a hand one.

    Jigs are great for things that are either A: really, really important and you can't afford to mess them up or B: things you're going to be doing a lot of. The mount itself works as a pretty effective jig for this I think.
    I did this…

    Name:  52DAE347-8E91-44E6-8CCF-06E39EB290CF.jpg
Views: 151
Size:  31.7 KB

    I can square it off more if there’s concern for walking?

  9. #39
    Member
    Join Date
    Jun 2019
    Location
    out of here

    Didn’t like it

    Looking at the picture I didn’t like the groove so I went back and made it flatter in the middle.

    I’m only like 1mm deep or so. You can still see part of the etched letters.

    Name:  C6326A61-2CE3-4C95-B84C-D92A18563888.jpg
Views: 173
Size:  41.7 KB

    Name:  54183A59-19E9-4309-8A2A-466B4C6704F0.jpg
Views: 164
Size:  23.7 KB

  10. #40
    Member
    Join Date
    Jun 2019
    Location
    out of here

    What is the pointy back end for?

    Is the reverse end pointy edge for accuracy / measuring / center finding?

    I had a hard time finding out from Google and I’m guessing it’s something simple?

    Name:  26E177BA-200A-4194-86EE-C1C987A06069.jpg
Views: 169
Size:  24.1 KB

User Tag List

Posting Permissions

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