Cam Clamp – Episode 3

Posted 11 March 2016

Categories: ,

This is an episode in a free series. Want to watch it? It is free to do so, you just need to log into the site, and you can enjoy this video and many other videos we think you will love.

Already a Member? Log in
Not a Member? Sign Up

There are a few steps left to finish the cam clamps. First, Paul inserts a screw to hold the head together. With that done he cuts a recess to accept the pivoting cam, carefully trimming it to size, before cutting the cam to size following a template. When completed, he drills through the whole head and fixes the cam in place using a roll pin. He drills and inserts the roll pins in the fixed head that will hold it in place. Then there is just the leather to fix to the pads and the clamps are ready for use.

Previous: Cam Clamp – Episode 2

35 Comments

  1. Thanks for another mini-series for such a versatile tool.

    If you make an extra cam head assembly(no need for the bar mortice) or use one from another clamp, the addition of a slot perpendicular and centred to the long axis, the width of the steel bar, will convert a cam clamp into an edge clamp. The extra cam unit is positioned in between and at 90′ to the jaws so that this extra cam head assembly puts pressure inwards when the clamp is in position. Making longer reach clamp heads makes the set-up work more effectively .
    Not my original idea, I saw it on the Chronos/quality-Woodworking-Tools site one time (the Czech makers Pinie supply them).

    May I ask, is that a small Cabinetmaker’s Rasp or a Modeller’s Rasp (from Auriou?) and what grain size?
    Thanks,
    Steve Hughes

    1. Sorry, that was somewhat verbose — A picture is self explanatory —
      Just do an Interweb search of
      “Pinie Edge Clamp Attachment”

      You’ll quickly get to the Quality-Woodworking-Tools website
      (Pinie also make a traditional Beechwood plane that combines a Rebate AND Bullnose plane for just £17 – worth taking a look at )

  9. Same way I’d come to you for woodwork advice Paul, if you can find an apprentice trained
    engineer in your new area, ask him about filing a round end?
    According to my training, the hand movement should be opposite the arc of the intended
    curve, where you follow the intended curve?
    Used when you file the wedges?

    2. The nature of wood grain necessitates filing exactly as Paul demonstrates. I could go into a lengthy explination, but it is much quicker if you simply go into your shop and file some wood for yourself. You will gain instant understanding. 🙂

      1. Greg,
        Precisely.
        I understood Paul and the reason for filing in that direction. I couldn’t figure out Dave’s comment, thought there might be some secret machinists handshake or something. 🙂
        Best,
        Craig

        1. I have to agree with Dave on this one. It really hasn’t anything to do with grain of the wood as you are pushing the file in the same direction. It is the kind of tilting movement you do to make the rounded edge that is different.

          The way Paul is doing it: While pushing the file forward, it is also tilted forward by rising the handle.

          The way I learned it by a metalworking craftsman many years ago: You start with the file fully tilted forwards. While you push the file, you tilt it backwards by lowering the handle.

          The pushing movement is the same, but you tilt the opposite direction. The benefit of this technique is that it is easier to create a circular curve that blends into the straight edges. The way Paul is doing it take much more care to avoid flattening the arc at the middle. I’m new to woodworking, so I didn’t know any better than using this technique on wood as well, and it works remarkable well.

          I’m pretty sure most metal working apprentices would get their hands slapped if they had used their file the way Paul does.

          Kjell

  12. Can anyone tell me where the countersunk bit that Paul used can be purchased. I have to admit I haven’t seen that type before but it does look to be very effective.

    Reference Mr Pawson’s comment on filing a radius, I can confirm that it isn’t some secret engineers handshake. In metalwork it is usual to file a round or curve (radio us) by filing in the opposite arc. Away from the work piece. It was certainly tought at my apprentice training school when I was a first year craft apprentice. Of course the material being worked was metal not wood and not every technique can be carried across successfully.

      1. Thank you Eric, I will check it out. I’m sure you are right, as regard availability nearer to my location. Oh, I live in Ireland but source most of my tooling both proffessional and hobby from the UK. Not a great choice of tool stores here and they tend to be more expensive than the UK. Love to purchase more from the U.S. but shipping and import taxes make that even more expensive.

        1. Hi Werner,
          I too am in Ireland (Cork) – Ebay ie is Not Good for tools – I use Uk also.
          The countersink has a nickname of ‘Snail’ or ‘Snail-Shell’ due to it’s resemblance to such creatures.

  14. I’ve greatly enjoyed making a set of four, except when I had a stiff lump in the last mortise, and wound up stabbing the 1/8″ chisel into my thumb.

    Still have to make the tear-drop tighteners, but that should be easy compared to the other bits. I think I’ve made every mistake possible on the mortises … cutting the hole at a slight angle to the right or left … only in a stationary or moving bit, not both; toe in, toe out. At least none are twisted relative to each other, so I expect they’ll work fine, even if they are a bit ugly.

    Next week, on to making a tiny box for my auger gimlets!

  15. Made a pair of these. The 1/8″ mortises were a struggle and several look like they were chewed out by a rat. They work fine though.

    Had enough material to make two extra movable heads and decided to reverse the cam action on them so that the cam arms are pressed down to close the clamp instead of lifted up. This seems like a more natural motion and counters the tendency to pull the clamp heads apart when lifting the cam arm. This is easy to do by simply relocating the pivot hole for the cam arms and seems to work very well. Everything else is the same and I can interchange the two types of heads. Did anyone else try this? Is there some reason why it isn’t done this way?

    1. Haha, I had similar struggle with the 1/8″ mortise. My smallest chisel is 1/4″. I couldn’t find a 1/8″ chisel anywhere locally except a woodworker store that wanted the price of 3 clamps for that chisel. So I actually used a 1/8″ drill bit and 1/4 and 3/4 chisels to clean out the hole enough to pound in the iron size it enough to clean up with paring with the 1/4.

  17. Great video series. Inspired me to make my own. Used mahogany and have cut all my 1/8″ mortices and fitted steel, shaped them, saw kerf relief cut.. Have to make the levers and cut and mortice the clamp heads for them. Drill holes and install pins. I must say their is wisdom in taking care to get those relief holes for the lever side of the clamp correctly located. My saw kerf ended up in the middle of one and I can tell it will break after putting pressure on it during clamping. I am going to make a new clamp head to replace it. Really enjoyed watching these videos and reading all the positive comments. Great job Mr. Sellers. Really enjoy all the great videos you’re putting out there. Definitely love the rebate plane making one. Super cool.

  19. I’m sure this exact method for creating this cam cramp was published in one of the woodworking magazines around 1989-92, and was probably one of Paul’s articles. Practical Woodworker maybe? Regardless, I still have mine from back in the day when I was still on the tools, made by myself from the information in Paul’s article.
    When I last used them about four years ago (progressive disability prevents me from getting to the bench these days), they still worked as well as they did when they were first made. A classic from Paul well worth the investiture. Excellent video, a big thank you to all.

Leave a Reply