Help with Gramercy holdfast technique - they are not holding

[Simon MacGowen]

but always chalked it up to my bench being 2 1/4 spruce. What works best for me is giving it a good whack with my 2lb lump or my framing hammer, the wooden mallet never worked.

That's interesting as I would have thought spruce, being softwood, would need less force for a holdfast to hold. Have you examined if the holes have been deformed (enlarged) over the course of continued hammering?

Simon

[Matthew Hartlin]

That's interesting as I would have thought spruce, being softwood, would need less force for a holdfast to hold. Have you examined if the holes have been deformed (enlarged) over the course of continued hammering?

Simon

I would expect that they have and I drilled them freehand with my brace so they could be a bit off plum. With that said I generally give them a good smack with a 16oz framing hammer(it's always near my bench) and they're fine.

[Bob Leistner]

I had a chinese copy of a traditional holdfast prior to the Gramercy holdfasts I am currently using. The old one held much better, with less striking than the Gramercy. Same bench same holes.

[Graham Haydon]

Warren's picture of Roubo's set up has long interested me. There is much more space around the holdfast, it's not a snug fit. This, to me at least, seems to create a wedging action. If the holes are too close to the size of the holdfast it won’t grip. I would experiment with hole size on an offcut.

I have owned a pair of “Gramercy” and they were ok. The other issue picked up by Stewie is how many cheaper holfasts are very smooth because they made from standard bar. I have a pair of holdfasts made by Simon James and the surface is nice and rough, they feel like coarse sandpaper in the hand. However I need to give them a try.

Derek, thanks for posting the video. We should all do more of it as it gets across what what works well for all of us. For me (not for you), your holdfast does not have enough bite.

Noah, it’s interesting you mention that type of holdfast. They are out there without the notches https://www.gshaydon.co.uk/blog/screw-type-holdfast and the one I have features the “stiching” Stewie shows.

Anyhow! I’d experiment with hole size and making the shaft more coarse.
blog_Holdfast_1.jpgJ V Hill Holdfast.jpg

[Derek Cohen]

Graham, the point about spring by Warren was very helpful. I am tempted to thin the heads of mine a little to see if this adds to the ease in holding.

I want to emphasise two points: the first is that these holdfasts do work well. Clearly not perfectly for all but, since there are so many variables in play owing to the multitude of bench to types and holes in use, we do need to explore factors outside the shaft or the head to understand the holding factors.

The second point follows from the first: do not try modifications until you have determined what is "wrong" with your set up. You could be compounding issues.

You may be correct that I set up does not grip well enough, and that it could grip more with adjustments. I have not noticed a lack of grip. If I wack the holdfast harder, and it grips better, what does this mean? That the head needs to flex more? That the shaft needs to jam more? Do I resort to trial and error for the assessment?

Regards from Perth

Derek

[Graham Haydon]

All good points Derek. The Gramercy style I had were working in a pretty thin top and were ok. I'll be experimenting on scrap before I drill my current bench project for the Simon James holdfasts I intend on using.

[Simon MacGowen]

At 3:35, it shows a steel bar holdfast in action:

https://www.youtube.com/watch?v=qt0QkXxogRE

This guy even oiled his bars!

Simon

[steven c newman]

IF only I knew how to weld....I could even build a couple....

[Simon MacGowen]

Can't you just hammer flat the end of the arm similar to the Gramercy design instead of welding a piece to the bar?

Simon

[Pete Taran]

Simon,

You sure can, but you might want to avoid the upsized cigarette lighter that guy uses and use a MAPP torch. Burns way hotter and actually gets the steel red hot instead of just warm like in that video. While you are at it, thin out the arms as you work by heating and beating until you get a nice tapered affair.

[Simon MacGowen]

Thanks, Pete. Could be useful advice for Steven if he decides to try.

Simon

[ken hatch]

The two Black Bear Forge holdfasts arrived yesterday, They are prettier than the TFWW holdfasts and a little thinner at 17.5mm vs. 18.3mm for the TFWW holdfast. The Black Bear Forge shaft is also "rougher", more texture than the TFWW's shaft. I A&B'ed the two holdfasts using the same test board, a short hunk of 8/4 Poplar, the same dog hole, and the same pad under the holdfasts on two of my Beach benches, I did not try them on the SYP bench. One bench has a 95mm (~3 3/4") slab the other slab is 90mm (~3 1/2"). The results were the same on both benches, The TFWW holdfast held very slightly better, I was unable to move the test board no matter what I tried. The Black Bear holdfast I could move very slightly with great force. The Black Bear was easier to release with just a light tap, the TFWW sometimes needed a couple of heaver hits to release.

Bottom line both worked. In day to day use the Black Bear might be more enjoyable to use because the hold is adequate and the release is easier but I sure wouldn't throw rocks at the TFWW holdfast. They hold their own with the blacksmith made holdfast (sorry sometimes I can't help myself).

ken

P.S. My TFWW holdfast are completely stock, no roughing, stitching, or any other change to 'em.

[William Fretwell]

I checked mine today, I thought I had varnished my Grammercy’s to slow rust but I had brushed the bottom half with epoxy mixed with bronze powder. The epoxy to slow rust, the bronze powder to increase friction. It also gives them a cool antique look.

[Simon MacGowen]

Bottom line both worked. In day to day use the Black Bear might be more enjoyable to use because the hold is adequate and the release is easier but I sure wouldn't throw rocks at the TFWW holdfast. They hold their own with the blacksmith made holdfast (sorry sometimes I can't help myself).

ken

P.S. My TFWW holdfast are completely stock, no roughing, stitching, or any other change to 'em.

Good to know. I wasn't surprised to hear this, having used the Gramercy holdfasts AS IS on three different benches made of different lumber and thicknesses over so many years with zero issues.

Simon

[Jason Dean]

I use Gramercy holdfasts in a 5.5" Ash bench. The dog holes were drilled with a brace and are chamfered (top and bottom) to stop the wood splintering. I can set them with palm pressure to the point that I have to tap them with a hammer to release them.

I've got an orange dead blow hammer I use to set/release them in typical practice.