Benchtop thickness for holdfasts

[Halgeir Wold]

I have an old scandinavian style workbench, but I find it too narrow for several tasks. An additional assembly table would do the trick, but my basement shop area is a bit cramped by your standards... only 18x10 '... so - amidst total renovations f downstairs, I'm concidering a new bench/table combo with vises, holdfasts etc.. Since "local" hardwood prices are quite insane, I'm thinking of using laminated oak bench tops..
40 and 30 mm thicknesses are easily avaliable.. ( appx 1.6" and 5/4" ).. what's the minimum recommended thickness for holdfasts, - which btw I've never used before???

[Jim Becker]

Traditional holdfasts tend to like thicker benches so they, well...hold fast...when you whack them down. My bench is a hybrid of both traditional dog holes that can be used with my "beloved" Gramercy holdfasts as well as a 20mm grid system that matches my Festool stuff. The three strips where the holdfasts can be used are about 60mm thick, but I suspect they would work ok with a thickness above 40mm. OTOH, the 20mm hole grid is only about 25mm thick because certain types of clamps cannot be used if the surface is thicker as you can't get the 90º end to go into the hole and clear the bottom.

[Halgeir Wold]

Ah.. thanks! I was thinking about glueing two together to achieve total thickness of 70-80mm... Seeing most benches are 4" or more I was wondering if 70mm would be enough...

[Jim Becker]

Bench thickness certainly varies from less than 50mm up to "a lot", depending on the bench type and personal preference. Holdfasts grip by ending up wedged at an angle in the hole to create a frictional hold so as long as you have a reasonable thickness, they will work fine.

[Don Stephan]

I'm not sure how well softer woods like poplar might work over time with holdfasts. I would suggest getting some pieces of the wood you are considering, glue up two or three different thicknesses, and experiment.

[Carl Beckett]

I have seen some inserts to use for dog holes - would mean the bench thickness might not matter as much

My bench is 3.5" thick and hold fine

[Tom Bussey]

Why not take some smaller blocks and drill the same size hole as the hole in the bench top and then line up the holes screw then in place. I say screw because I do not know what you top is made of just thinking of wood movement and possible a cross grain glue up. Carl says 3 1/2 inches thick works fine make you final thickness what ever you want. I would make the blocks out of a hard wood even if you top is a soft wood.

I built a Nickelson style bench out of southern yellow pine for my grandson and did that of it and they work fine. Blocks only need to be 3 x 3

[Phil Gaudio]

You might reconsider the type of holdfast you are using. This is the Veritas Hold Down:
05G1401-veritas-hold-down-u-0068.jpg

I am currently using this in an auxiliary dovetailing bench with a top thickness of 1" and a drill press table with a thickness of 3/4": it works exceptionally well in both. It also works extremely well in a 4" thickness bench top. It is apparently available in Norway:

https://verktoyas.no/produkter/tving...e-oe19mm-feste

If you are lucky, perhaps they will be having a tilbud on it!

[Halgeir Wold]

Thanks a lot!! Unfortunately that company doesn't have much on sale - even after doubling or tripling the US prices....

[Anuj Prateek]

I found 4" to be too thick for Gramercy holdfasts. They work nice with 3-5/8" thick top.

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I have Gramercy holdfasts and construction lumber bench. Top is ~4" thick. Holdfasts did not work properly. Sanding the holdfasts and slightly enlarging the holes did not help.

I used a cold chisel to create dimples on shaft of one of the holdfasts. Kind of like how it is on rasps. This one started perfectly. Don't even have to whack it to make it hold. Light push does the trick. However, it started scraping the walls of the holes.

Then I used a round over but over holes. Effectively reducing the depth by 3/8". Other holdfast started working good as well.

[Bob Jones 5443]

I glued and screwed two 2’ x 6’ birch butcher block slabs together for my bench, which has served me well for over fifteen years now. The slabs came from IKEA; each is about 1-1/8” thick, so the bench is 2-1/4” thick. I drilled 3/4” dog holes in a 6” grid across the full length and three rows deep. There’s a screw from below, one inch away from every dog hole, and also on a 6” grid in the back third of the bench. The screw grid ensured a successful lamination.

My Grammercy holdfasts work beautifully. With a determined whack from a rubber hammer, they hold as securely as any vise on the bench.

I don’t think you need a 3” bench. Mine is about 200 pounds and quite robust.

Good luck with your bench.

[fritz eng]

My bench top is 1 3/4" maple with 3/4" dog holes. Ordered my Gramercy holdfasts this year. Can't be happier with them. One whack and that's it! Highly recommend them at a great price for a pair.

[George Yetka]

https://www.toolnut.com/festool-5771...8aArx-EALw_wcB

I picked up a couple of these for my MFT a couple months ago and they work very well.

[Jim Becker]

My bench top is 1 3/4" maple with 3/4" dog holes. Ordered my Gramercy holdfasts this year. Can't be happier with them. One whack and that's it! Highly recommend them at a great price for a pair.

There's a reason I tend to use the word "beloved" in front of Gramercy Holdfasts when referring to my own. And they are the real reason my main bench has three rows of stodgy old 3/4" dog holes in thicker material instead of just the grid of 20mm holes on 96mm centers that the rest of the bench has. I built my bench the way it is because of those thangs specifically.

[Mark W Pugh]

My bench top is 1 3/4" maple with 3/4" dog holes. Ordered my Gramercy holdfasts this year. Can't be happier with them. One whack and that's it! Highly recommend them at a great price for a pair.

I have a mobile work bench with 2 ea 3/4 ply glued together for the top. So, 1 1/2 thick, 3/4" dog holes, and these work great https://www.amazon.com/DCT-Bench-Hol...iABEgIqG_D_BwE

Never had a problem with them releasing while working on a project. Same concept as Gramercy product, just cheaper.