Kant Twist alternative?

Nice job Jason. I think I prefer Bernard’s design though as it looks likely to be more rigid. I only lost some of the angles on mine to make it easier to cut out.

If anyone can get the arms water or laser cut at a good price I’d be interested in a couple. Probably 2” or 3”.

The site for Bengs in Germany has them for sale, not sure what they would cost by the time the import, vat and postage was added

https://www.bengs-modellbau.de/werkzeug/werkzeuge/parallelzwinge-spannhand?number=3431

Once you have a suitable search term - Parallelzwinge, it opens up all possibilities!

**LINK**

Having had a bit of a play it seems that the angled larger plate allows the clamp to poen further than just a basic "L" shape would and the two legs can open until parallel like the drawing in Vics link that give sthe clamp sizes.

Those reading the current CAD thread will have seen my mention of how useful it is to be able to animate parts once assembled, this is a good example as I was able to see that the screw thread needed to be made 10mm longer to allow the clamp to fully close and that the spacer nearest the nut needed to be moved outwards from teh pivot so the smaller arms would not hit it. Even the jaws faces stay parallel, screws left out for clarity. I just need to fine tune that quick release thread

Due to the method of manufacture the original design required additional riveted spacers to ensure rigidity? This does not appear to be the case with my bolted version. As a result I’ve left two of these elements out of the design. After some little testing they don’t seem to be needed. I can, if required, fit two screws to the unbolted boss or add an additional spacer, but as said it doesn’t seem to be required. Time will tell so I’ve left my options open. Sometimes home machinists are not constrained in the way manufacturers seem to be. A big advantage for me as a home machinist is that using a bolted rather than riveted design is that I can make and exchange custom clamping pads as required. Whether I need to do this though remains to be seen but it is an option not afforded by commercial versions.

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It’s an ‘engineering balance’ really … Any additional spacers [adequately made and fixed] will increase the stiffness of the beam … up to the point where the beam becomes solid.

BUT, in reality, each spacer brings with it a hole in the plate [etc.]

This is where Finite Element Analysis comes to the fore.

MichaelG.

I stuck 4 small ones in a shopping cart to see what additional costs. Postage was quoted as 4.20 euro inc vat at 19% and the original prices shown were also vat included: presumably we buy vat free and pay 20% this end +.- any extra customs handling?
..not that I bought any.

The link Vic produced was a more complicated shopping cart I didn't want to fill details into so not sure what delivery and vat may apply.

pgk

I'll leave the FE to someone else.

However if the holes are kept on the mid line of the plates their effect will be minimal, much like drilling joists within the neutral zone is acceptable upto a certain diameter or why a castellated bean can be riddled with holes.

It's only when the postie squashes it sideways that the holes will have a greater detrimental effect on strength !

If you change the shipping destination from Germany to UK the shipping cost goes up to €15.

Jason,

My inclusion of [ etc. ] was pertinent … the behaviour of such an ‘assembly’ is much more complicated than that of a homogenous beam with holes in the web.

MichaelG.

Have any of you bought this “plates” only kit?

**LINK**

I’m just wondering how much the postage is and whether you got hit with import duty, tax and courier charge etc.

Hi Guys,

The design details for the "Kant Style" clamp are here ! Using this information any size clamp can be produced simply by drawing two circles.

NOTE: that this this drawing is provided for personal use only. Not for any commercial use.

Copyright remains with me and MEM magazine.

I bought the complete kit & no extra duty, tax or courier charge was added, took a long long time to arrive but to be fair the project has not been started yet. Just fill in the order form to find out postage cost.

Tony