The ancient Holdfast

[formariz 11,865]

On a flat work top the Holdfast has no peer. Nothing even comes close to its effectiveness and versatility . As it’s name implies it will clamp anything on a table from1/16” to 12” or more, fast and securely. Besides a wedge it is probably the oldest work holding device ever. There is evidence of its use for over one thousand years. 
 Although still somewhat available it is being increasingly hard to find pricing reflecting it. In its simplest most primitive form it is something fashioned by any competent blacksmith. There are a few commercially made versions but they are too small and not really constructed correctly.

 The modern version of it adjusts with a hand turned screw and has an articulated arm unlike the ancient form. It was made by our friends across the pond and like every tool they make an example of quality and craftsmanship. I believe it is no longer made. Years ago for selfish reasons I essentially cornered that market by buying every single one that showed up. 
 

  The mechanics of it couldn’t be any simpler. All types work by inserting them through a proper sized hole on bench top. It’s the diagonal wedging action of its shaft through the hole’s thickness that creates the clamping action. New versions will have a steel collar that is mortised into top to reinforce hole and prevent wear and are tightened with a vise like screw. On the traditional form ,one one simply hits the top of it with a hammer to clamp or hit the back of it to release.The arm on it also flexes increasing the clamping force. 
 

 They are mainly a woodworking tool although very rarely seen there are ones made for stone carvers that get “ nailed” onto a beam rather than using a hole . The arm slides up and down on the shaft to a accommodate material thickness. Wedging of arm on the shaft creates the clamping action. These are really unique to where I am from. 
 Most will use only one or two holes on work bench. I however use six strategically placed along length of bench .  If outside of its clamping range a simple “ extension “ is used with them.

 
Traditional and modern versions

 Depending on task several may be used

  Some of the NOS for grandchildren’s future benches

 Modern version complete with collar and mounting hardware

 
 Reinforcing collar also adds additional mechanical holding ability with ridges making it impervious to accidental release from vibration. 

 

Large capacity

 

 The secret to it , the wedging action

 

Extending its range

 
 

On traditional version clamping occurs by hitting top

 

To release hit back

 

Unique stone carvers version

 Used at quarry site by nailing it to a wide beam

 Arm slides up and down on shaft . Clamping happens by hitting arm

 

 

 

Edited February 3, 2022 by formariz

[stevasaurus 22,235]

Love that hammer you use for those clamps.  

[ri702bill 7,362]

Looks to be the predecessor to the current day milling machine step clamp - same principal.

Bill

[formariz 11,865]

36 minutes ago, stevasaurus said:

Love that hammer you use for those clamps.  

Stone carvers mallet. Compact and with the weight concentrated in the right area. Can be used with total control within your palm like it was your hand. I prefer it to any woodworking mallet for most tasks. Comes in different weights. This one is 1k or 2.2pounds. A lot of weight right inside ones hand.

 

[formariz 11,865]

29 minutes ago, ri702bill said:

Looks to be the predecessor to the current day milling machine step clamp - same principal.

With a few distinct differences but yes. Nothing new is “so new” . 

[ebinmaine 63,272]

VERY nice. Thanks for taking the time to post.  

 

I'd love for Trina to have a larger more permanent workspace/bench/counter with which she could better utilize things like that. 

 

[formariz 11,865]

4 hours ago, ebinmaine said:

VERY nice. Thanks for taking the time to post.  

 

I'd love for Trina to have a larger more permanent workspace/bench/counter with which she could better utilize things like that. 

 

Even in a not so permanent location they can be used. All you need to do is drill a hole. I have done that many times on job sites in the past.

[John2189 407]

For the original holdfasts, how thick does the bench have to be? Would a top of 3/4 plywood work?

[formariz 11,865]

5 hours ago, John2189 said:

For the original holdfasts, how thick does the bench have to be? Would a top of 3/4 plywood work?

Yes it does. The plywood however will wear out quickly around the edges from the wedging action and will also splinter depending on its quality. You can introduce a collar. They can be improvised from a variety of items. I have in the past also made a solid maple insert for plywood. Just a square piece mortised and screwed to plywood that could also be replaced. 
 Top can also be too thick for them to work properly. One then has to counter bore the underside. The ideal thickness is about 1-1/4” although they work perfectly well with 3/4”. Too thick of a top will reduce the diagonal wedging action that you can clearly see on the photo below. That is the secret to how it works. Correct hole size is also important although there is a bit of leeway there.

   Used on 3/4 maple board

 

On 3/4” it’s actually a good wedge action 

 

Various collars used in past at job sites for different size holdfasts

Edited February 5, 2022 by formariz

[John2189 407]

Ok i was kicking around trying them, just never have 

[formariz 11,865]

1 minute ago, John2189 said:

Ok i was kicking around trying them, just never have 

Do it. You will never regret it. 

[John2189 407]

Thanks