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Thread: Gramercy Holdfast Help

  1. #1
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    Gramercy Holdfast Help

    I bought a set of these a while back, but found they didn't hold very well, so I fixed them up as per this video https://www.youtube.com/watch?v=S7lnfW4iT6o
    Still, they "stick" but they don't hold. even if I hit them in with quite a bit of force I can still swing the board around with ease, I have resorted to using clamps again.


    Now, based on everything I've read and on that video, I think hold fasts are supposed to hold much stronger than what I'm getting, right?


    The round do holes in my bench are 2 1\2 inches deep, others are 1 1\4 . all holes are 3\4inch in size. I'm wondering maybe I need deeper holes? different size? I'd like to make holes on the side of the bench too and really enjoy the holdfasts, but not until they can hold stronger than a 5 year old kid

    a friend of mine has a set too and they don't hold any better than mine so I don't think I got duds.

  2. #2
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    Is the problem that the hold-fasts are not staying in the holes, or that the workpiece is pivoting? Is it able to clamp down tight on a small chunk of wood, or is even that weaker than desired? does it never hold tight, or is it loosening as you are trying to work?

    What is your bench made from, and what surface treatment does it have?

    My bench is ~3" thick (unfinished doug fir) and the hold fasts stick well when whacked in with my wooden mallet. Thicker tops reportedly have more problems holding the hold-fast, with the general suggestion being to counterbore from underneath (rather than the hold-fast dimpling shown by Richard in the video). I'd expect that your 2.5" holes should be pretty much ideal. I don't have experience with 1.25" thick top.

    How tight are the holes around the hold-fasts when first dropped in? (i.e., is it hard to insert the hold-fast, do they drop in, or do they have a lot of space around them?)

    If the issue is the workpiece moving despite having the hold fast staying fast… how flat is your bench (and workpiece), and what finish do you have on it?

    PS--in frank klausz's recent video on joinery, he is setting up his post-retirement shop and uses some TFWW hold-fasts. He did have some trouble when chopping on a table leg. In that case, his workpiece was pretty thick, so the hold-fast was pretty high (workpiece thickness + scrap), he was using a single hold-fast, and he was starting to get some vibration in the workpiece when he was chopping. The hold-fast loosened up with the vibration. He switched to a clamp at that point. He was using the hold-fast later without any problems, when chopping out drawer dovetails.

    Matt
    Last edited by Matthew Hills; 07-12-2014 at 10:45 AM.

  3. #3
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    I had the same problem. The holdfasts would get nice and tight, but the wood still was able to move some. Glueing leather pads on each of the holdfasts fixed that. Now they are rock solid with just the lightest tap to secure them.

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    Thanks Matthew, lol.

    the workbench is flat, top surface is poplar, unfinished, but most of the doghole is beech.
    the holdfast have just little room in the hole, not tight but not at all loose.

    the issue is as you said, the holdfast stays put very well, but applies very little pressure to the work piece no matter how hard I tap it in.

  5. #5
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    Quote Originally Posted by jason thigpen View Post
    I had the same problem. The holdfasts would get nice and tight, but the wood still was able to move some. Glueing leather pads on each of the holdfasts fixed that. Now they are rock solid with just the lightest tap to secure them.
    I tried that. now 1 has a leather pad and one is bare so I could see the difference, but they are both the same.

  6. #6
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    Hi Jim, I mentioned in the first post the I had already done that. maybe there is something wrong with my holes. the first 1" is plywood, maybe thats the isuue. I'm going to experiment and
    see how it goes.

  7. #7
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    My bad, I wasn't paying attention and that's a peeve of mine (when other people do it).

    Did you raise enough metal around the pin strikes to feel a roughened surface?
    If so, I think you may need to inlay a hardwood strip in your existing bench.

    The plywood may have fractured in use, enlarging the holes.

    Have you any detail pictures of the problem?
    It's of interest as workholding is an elemental concern for benches.

  8. #8
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    A single holdfast will not prevent a piece from pivoting.

    If the holdfast is lightly tapped down with a mallet, pulling straight up on it should not cause it to release.

    A holdfast needs to be a little loose in the dog hole in order to have room to become jammed. Your comment, "the holdfast have just little room in the hole, not tight but not at all loose," leads me to believe your holdfasts may need to have a larger hole than a standard dog hole to get a grip.

    I use my holdfasts on a piece of 2X construction lumber that is the top of one of my sawing benches.

    My suggestion would be to also try some scrap lumber with different sized holes to see if it is the fit in your bench dog holes that might be the problem. The solution would be to bore some holes only for use with the holdfasts.

    My holdfasts were made by Harry Strasil and work fine. My recollection is the shafts are made of 5/8" rod.

    My biggest problem seems to be my bench's material can split a bit if they holdfast is driven too enthusiastically with a mallet.

    jtk
    "A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
    - Sir Winston Churchill (1874-1965)

  9. #9
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    Quote Originally Posted by Matthew N. Masail View Post
    I tried that. now 1 has a leather pad and one is bare so I could see the difference, but they are both the same.
    From this, it sounds like you're only using one holdfast at a time to secure something ? If that's the case, i can often rotate things under a holdfast when using it in this fashion, because it's held by a single point, depending the board and how far from the holdfast the working end is. For something like chiseling dovetails (where all the force is focused downwards) it's not much of an issue, but depending on how you're applying force, it may be a problem. Often times, just butting the free end of the board against the shaft of the holdfast is enough, but usually I would either use two holdfasts, or a holdfast and a bench dog, depending on what I'm doing, and how the force is being applied.

    When working with softer woods, I often use a piece of scrap underneath to keep the holdfast from marring the workpiece, this seems to also help secure things a little better, as well.
    Last edited by Jessica Pierce-LaRose; 07-13-2014 at 12:20 PM.
    " Be willing to make mistakes in your basements, garages, apartments and palaces. I have made many. Your first attempts may be poor. They will not be futile. " - M.S. Bickford, Mouldings In Practice

  10. #10
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    Jim M, I know what you mean, I do it too sometimes out a laziness and then always feel like I was goof. If the experimenting doesn't fix it, than I'll take a video of the issue.




    Jim K, "A single holdfast will not prevent a piece from pivoting" thats good the know! but still it should be somewhat firm, I can move it by breathing on it the right angle!
    I am going to experiment with some construction lumber and see how it goes, I've had a feeling since Matthew H asked that my holes are really a little small. the metal raised from the hammering made this worse, so I filed off the peaks and it's still rough but the tilt and grab are a little better. also I think the plywood layer gives in more than the wood underneath it making the tilt uneven. I'm planing on a new bench so this is definitely something I'd like to solve first!




    Thank for all the help ! will post results when I get it right.
    Last edited by Matthew N. Masail; 07-13-2014 at 12:25 PM.

  11. #11
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    it should be somewhat firm, I can move it by breathing on it the right angle!
    Usually when I jam a holdfast into a dog hole onto a piece the holdfast will not easily pull out.

    So far all that has been said makes me think the dog holes are too close to the holdfast shaft's size to work properly.

    I'm planing on a new bench so this is definitely something I'd like to solve first!
    This is something a few auger bits, a brace and a little time should help you to find the best size hole for you holdfasts. My plan is to have separate holes for the holdfasts and bench dogs. The dog holes will run close to the edge and the holdfast holes will be set in from the edge a few inches.

    jtk
    "A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
    - Sir Winston Churchill (1874-1965)

  12. #12
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    Quote Originally Posted by Jim Koepke View Post
    Usually when I jam a holdfast into a dog hole onto a piece the holdfast will not easily pull out.

    So far all that has been said makes me think the dog holes are too close to the holdfast shaft's size to work properly.



    This is something a few auger bits, a brace and a little time should help you to find the best size hole for you holdfasts. My plan is to have separate holes for the holdfasts and bench dogs. The dog holes will run close to the edge and the holdfast holes will be set in from the edge a few inches.

    jtk
    Sounds good. it's pretty much the set-up I Imagin, Thank g-d I have a friend who has a brace and auger bits.

  13. #13
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    Quote Originally Posted by Matthew N. Masail View Post
    Sounds good. it's pretty much the set-up I Imagin, Thank g-d I have a friend who has a brace and auger bits.
    I would be lost without my own brace and bits.

    So much so is my feeling about this that there are now a few more braces in my shop than I will ever use.

    Sadly, it looks like shipping to Israel is more than any or all of the braces are worth.

    jtk
    "A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
    - Sir Winston Churchill (1874-1965)

  14. #14
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    Quote Originally Posted by Jim Koepke View Post
    I would be lost without my own brace and bits.

    So much so is my feeling about this that there are now a few more braces in my shop than I will ever use.

    Sadly, it looks like shipping to Israel is more than any or all of the braces are worth.

    jtk
    Yeah but I'm blessed with relatives in the US, so It should be ok when the time come! my friend who has a set in 1\16 increments just bit the bullet.. also a way to go.

  15. #15
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    my friend who has a set in 1\16 increments just bit the bullet.. also a way to go.
    A bullet I can't seem to stop biting. It is hard for me to resist bringing home decent bits if they are priced right.

    jtk
    "A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
    - Sir Winston Churchill (1874-1965)

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