Holdfast Group Buy - May have found a UK Blacksmith

[wizer]

Richard, the vast majority will be using 19mm / 3/4inch That's what the gramercy ones are designed also. The only altering factor that any hold fast may come into some problems is the thickness of the bench. Too thick and it won't work. Too thin and the hole will get damaged by the locking action.

You'll be fine with the 18mm stock.

 

[9fingers]

18.2mm will be the imperial size 23/32" used by the merkins. I'm sure 18mm will be fine for this type of clamp.

Bob

 

[AndyT]

Richard - this is sounding very encouraging!

Here's a suggestion: assume a depth of hole / benchtop thickness of 2" and optimise your design for that. I think that will be a common actual depth.

Anyone whose top is thinner can glue on a block of wood under where they drill each hole, to bring it up to 2".

(If anyone has a super-thick bench they could counter bore the extra thickness at the bottom, using a bigger bit, reducing the depth of the 3/4" part of the hole.)

 

[jlawrence]

I'll take 2 pairs as well - please.

 

[mickthetree]

I'll take 2 pair off you as well if its not too late. I agree with Tom it would be good to get some prototypes tested, but I'm happy to take the word of some forum members.

 

[wizer]

At which postage price bracket would people accept a pass around? If it's around the £4 mark, would that be useful for people. Or do you want to trust the review of a couple of members? For example I could send mine to someone like Alf or Philly?

 

[BMac]

I trust people with more experience than me so, knowing nothing about holdfasts, I think a couple of reviews is ample.

Brendan

 

[sqwheezle]

I'm happy to accept the opinion of a couple of members. My bench top is 4 inches thick but the counterbore idea should work fine.

 

[Richard T]

Right: as I thought, 18mm it is.
Andy the counter bore idea is brilliant. Not so sure about gluing extra on though... would probably have to be thickening the whole of the holes with wood of decent proportions - I should think that small piece extensions would get popped off quite easily.
Mick - it's not too late, it's too early. I haven't got the stock in yet.
Hopefully I can get some pictures up tomorrow.

 

[AndyT]

On the thickening idea - I was imagining a block of (say) 4" x 8" under each hole, screwed and glued up to the top - it all depends on the layout of your bench, and where you want the holes - but hey, we're resourceful people!

 

[ondablade]

Just theorising. The slightly smaller diameter of the stock the new holdfasts will be made from might just improve it's ability to grip in a 3/4in hole in a thick bench.

Some sort of light texturing of the shank seems (judging by mag articles) to help the grip too. I wonder if there's any cost effective and visually appealing option in this regard that would be worth testing, and if it works could be cost effectively applied/offered as an option? e.g. shot blasting? It'd be better if it didn't make it too abrasive.

 

[PeterBassett]

As I've said, I'd be happy with the opinion of Tom and whoever he can send to Philly, Alf etc.

As for shotblasting, not sure. My worktop is just over 2 inches of mdf. Since it is fairly soft stuff I'd rather the holdfast stick from the sideways wedging action rather than from it being inherently rough.

Thoughts?

 

[wizer]

My gramercy holdfast is smooth and works well in a 2.5" ply mdf sandwich workbench top.

 

[PeterBassett]

Job's a good 'un.

 

[Richard T]

Tom, I wonder if you could do me the favour of mesuring your Gramercy from square to the shaft out to the tip of the toe?
The first two I have made might be slightly longer in reach, the third is shorter and looks more like the Gramery - but that official picture makes it tricky to judge proportion. (Maybe they don't want people copying 'em )
Btw, there is no discernable difference in efficiancy in the longer or shorter, it would just be nice to know to bear in mind.
... And I'm sure that nothing would be added by mottling the shaft surface in any way other than more quickly worn holes. It's hard to imagine until you acually use one but as soon as you do, and feel it lock up, it is immediately obvious that smooth is good.

 

[wizer]

Richard. My Holdfast is with the blacksmith I found at the moment, I will have to go back down there on Friday to collect it. I'm sure there's someone else here with one who can offer those measurements?

 

[Richard T]

Aha. Thanks Tom. It's not nessasserrcccrry, was just curious.

 

[simonm]

Hello All

De-lurking to get involved in this if I'm not too late.
Interested in two please Richard.

simonm

 

[Richard T]

I got hold of some 18mm bar this morning.

It's nice to work with something more substantial. Notice the bellows pumping arm is a blur ...

Using the angle template.

Flattening the foot.

Holdfast holding fast.

Foot detail.

I'll pack one up and send it for scrutiny tomorrow.

 

[Mike.C]

No pictures Richard

Cheers

Mike