hitting holdfasts with metal hammer

[Günter VögelBerg]

Is this an ok practice? I have the gramercy holdfasts and the crucible lump hammer. If I use my weighted rubber mallet I have to really pound on it to get a tight hold. I suspect this has to do with geometry issues in the holes in my bench. I find myself just using the metal hammer, but I am always a little bit afraid of causing chips of steel to fly or breaking the holdfast or something.

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[ken hatch]

Is this an ok practice? I have the gramercy holdfasts and the crucible lump hammer. If I use my weighted rubber mallet I have to really pound on it to get a tight hold. I suspect this has to do with geometry issues in the holes in my bench. I find myself just using the metal hammer, but I am always a little bit afraid of causing chips of steel to fly or breaking the holdfast or something.

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tt
Gunter,

I've used lump hammers on holdfasts for years and the Crucible hammer once they were available with no problems. The bounce of a rubber hammer makes it difficult to set a holdfast.

ken

[Kris Cook]

I also have the Grammercy holdfasts and generally don't use a steel hammer to set them. This hammer is made by Estwing and is about $15 at the orange box store. It seems to be a good compromise between steel and rubber or wood.

[Tom M King]

That's the one I use on molding plane wedges. I keep one in each of the molding plane tool boxes, along with a little brass hammer.

Vaughn makes a similiar red, and yellow headed hammer with softer heads than the Estwing. I use if for some tile work. They're sold in Lowes.

[john zulu]

I have the same concern. I used dead blow hammer with nylon head. No issue and safer

[Jason Martin Winnipeg]

I use the Crucible hammer to set my Gramercy holdfasts. I've had no issues. If your Gramercy holdfasts aren't holding very tight, something you can do its to roughen them up with some 80 grit sandpaper, primarily focusing on the outside of the shaft. You can also make some small dents in it like a hand stitched rasp.

https://www.youtube.com/watch?v=S7lnfW4iT6o

[mike stenson]

I've had those holdfasts since they started selling them, while I use a shot filled carving mallet (because it happens to store nicely in my bench).. I'd not worry about hitting them with a lump hammer. They're spring steel.

[Jim Koepke]

My problem with setting them hard is the apron on my bench has split on the underside.

My holdfasts were made by Harry Strasil, AKA Junior. They have a 5/8" shaft going into 18mm-3/4" holes.

Most of the time just pressing them with my bare hands holds them in tight.

jtk

[Desi Kovar]

I tried the sand paper thing and that sort of worked on my Gramercy holdfasts. Rubbing a little bit of rosin on them worked better. You can buy rosin that is used for the bows of string instruments for a few bucks and a block lasts a long time if you apply it every month or so. I think I got the idea from Chris Schwarz’s gift guide from a few years ago or maybe somebody mentioned it on this forum.

With the rosin, I can set the holdfasts by hand and they work surprisingly well, but I tap them with my wood is good mallet when I went them to really hold.

[Derek Cohen]

Is this an ok practice? I have the gramercy holdfasts and the crucible lump hammer. If I use my weighted rubber mallet I have to really pound on it to get a tight hold. I suspect this has to do with geometry issues in the holes in my bench. I find myself just using the metal hammer, but I am always a little bit afraid of causing chips of steel to fly or breaking the holdfast or something.

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Hi Gunter

There are two issues here. The first is whether you will harm the Gramercy Holdfast using a steel mallet? The answer is that this will not do so.

The second issue is whether you need to "pound it", as you state you do. The answer again is a negative - this should not be necessary at all!

I made this short (2 minute) video to demonstrate how I use my Gramercy Holdfast since I can write these things, and still others do not believe me. If you cannot do as I do, then your set up is the issue. I hope my voice does not send you to sleep ...


https://www.youtube.com/watch?v=OaI_E2Yv1O0

Regards from Perth

Derek

[Hilton Ralphs]

I hope my voice does not send you to sleep ...

Derek

Derek, glad to hear your accent has not been corrupted by that Aussie twang.

[Frederick Skelly]

I use a wooden mallet on my grammercy holdfasts. It works well on my bench.

[Bob Jones 5443]

Derek, you just called me a big guy in another thread, but I think you’re the one. I’d hurt my hand whacking that steel bar.

I’ve sanded my Grammercy holdfasts per their instructions. My beech bench is 2-1/4” thick with 3/4” dog holes. I was using a 373 g Japanese metal hammer, but I was denting the softer steel holdfast with it. I even raised a little sharp burr that drew blood when I idly tried to flick it off. Also, the loud PING when I struck the thing hurt my ears. I tried a cheap rubber hammer and both dents and noise were solved.

[Jim Koepke]

Here is an old video of my holdfast being set with hand pressure > https://www.youtube.com/watch?v=2eCf7TTsp2E

jtk

[Frank Pratt]

I use my wooden mallet, because it's always there at the bench. It just takes a gentle tap for most things, but if I need a vise like hold, a good whack will do the trick. And then it REALLY holds.

[Andrew Pitonyak]

I was told to not hit them with a metal hammer because you can cause metal fatigue.... So i always hit them with things that are not metal. I am not well enough to say one way or another in that regards.

I can say that I do not need to beat it to make it stick. Mr. Cohen has it right I think.... but I think he also said you can hit it with metal.

I suspect that even if you are causing metal fatigue with metal on metal it would take a long time to manifest.

[Rob Luter]

I smack them with the mallet below. It's a cast iron body with a drop through handle in a thru mortise. It goes together just like a joiners mallet. The striking faces are white oak that I carved to fit (no lathe). I added a leather disc to one for a softer blow. I'll bet it once had rawhide faces but when I bought it at a flea market it didn't have any. I've never seen anything quite like it. It's heavy like a lump hammer. There are no markings of any kind. I'd like to learn more about it if anyone has any ideas.

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[Gary Focht]

I use hard face of the Thor hammers like Paul Sellers uses on his chisels. Works great for me.

[Frank Pratt]

I suspect that even if you are causing metal fatigue with metal on metal it would take a long time to manifest.

Like about a thousand years.

[ken hatch]

Like about a thousand years.

Thanks Frank, you have me ROTFLMAO.

ken

[Günter VögelBerg]

Hi Gunter

There are two issues here. The first is whether you will harm the Gramercy Holdfast using a steel mallet? The answer is that this will not do so.

The second issue is whether you need to "pound it", as you state you do. The answer again is a negative - this should not be necessary at all!

I made this short (2 minute) video to demonstrate how I use my Gramercy Holdfast since I can write these things, and still others do not believe me. If you cannot do as I do, then your set up is the issue. I hope my voice does not send you to sleep ...


https://www.youtube.com/watch?v=OaI_E2Yv1O0

Regards from Perth

Derek


Thanks fro the great info. So on some of my dog holes I can just push down and get a satisfactory grip for anything other than banging out mortices, but on most I can't. I've never really figured out what the difference is.

[Frank Pratt]

The thicker the top, the more slop you need in the hole, to a point. My top (hard maple) is just over 3.5" thick, the holes are exactly .75" and that combination seems about perfect for the Gramercy holdfasts. A much thicker top would need holes just a little bigger.

[Derek Cohen]

The thicker the top, the more slop you need in the hole, to a point. My top (hard maple) is just over 3.5" thick, the holes are exactly .75" and that combination seems about perfect for the Gramercy holdfasts. A much thicker top would need holes just a little bigger.

Or, chamfer the holes from the underside (to "reduce" its thickness) if the bench is greater than 3 1/2" thick (my bench is 3 1/2").

Regards from Perth

Derek

[Derek Cohen]

Derek, glad to hear your accent has not been corrupted by that Aussie twang.

Hilton, not a lot, although it depends with whom I am talking. I have lived here most of my life. Nearly 35 years in Perth, and Sydney before then. It’s hard to leave Cape Town behind.

I tend to be soporific, regardless :)

Regards from Perth

Derek

[Michael Bulatowicz]

Like about a thousand years.

You're not exaggerating. From a metal fatigue standpoint the those particular holdfasts are very well designed; long story short, unless there's some kind of internal flaw in the metal you'd almost certainly destroy your bench in short order hitting the holdfast hard enough to even consider approaching the fatigue limit*.

*Fatigue limit: the cyclic load limit, below which a steel object will never break no matter how many load/unload cycles it goes through.

[John Keeton]

I don’t use holdfasts these days very often, certainly not as much as most of you guys. But, I have a pair of Taiwanese holdfasts that are at least 15 years old. Every time I use them I swat them with a hammer. I can barely tell they have been hit.

[Jason Martin Winnipeg]

Hi Gunter

There are two issues here. The first is whether you will harm the Gramercy Holdfast using a steel mallet? The answer is that this will not do so.

The second issue is whether you need to "pound it", as you state you do. The answer again is a negative - this should not be necessary at all!

I made this short (2 minute) video to demonstrate how I use my Gramercy Holdfast since I can write these things, and still others do not believe me. If you cannot do as I do, then your set up is the issue. I hope my voice does not send you to sleep ...


https://www.youtube.com/watch?v=OaI_E2Yv1O0

Regards from Perth

Derek

My Gramercy holdfasts definitely don't hold that easy. I have to give them a good wack with a hammer or mallet to get them to hold tightly. I guess my set up is the issue, but how do I know what about my setup is the problem?

[Joe A Faulkner]

How thick is your bench? What did you use to drill your holes? How smooth are they? Note Derek mentioned his holes are slightly larger than the shafts of his hold fasts allowing for room for the shaft to bind. He also noted the walls of his holes are rough. In my 3.25 inch thick maple bench the holes were bored using a router bit. This resulted in extremely smooth holes. The Gramercy hold fasts would not hold until I abraded the shafts a little. I can now set them by hand but prefer to use a leather faced jointers mallet.

[James Pallas]

I wonder if the geometry, metallurgy, and the placement of the setting blow has more to do with it then the type of hammer used or bench thickness.

[Jim Koepke]

I wonder if the geometry, metallurgy, and the placement of the setting blow has more to do with it then the type of hammer used or bench thickness.

My answer would be yes. Just pushing my holdfasts against the work will secure it without a bash from a mallet.k

This has me wondering also. A holdfast needs to have a bit of slant to hold in the dog hole. There are three points of contact to fix a holdfast. The front of the rod, the back of the rod and being lightly sprung on the work have to all be working in order for the holdfast to hold securely.

If a dog hole is too slick along with a super smooth holdfast it likely will not hold as well. Another problem would be the holdfast being almost the same size as the dog hole. The thicker the top of the bench, the less of a slant for the shaft of the holdfast.

jtk

[Frederick Skelly]

I just got to thinking - has anyone tried a 2 pound brass mallet? Seems like it would pack a punch without causing a dent or bur on the holdfast?

[mike stenson]

I just got to thinking - has anyone tried a 2 pound brass mallet? Seems like it would pack a punch without causing a dent or bur on the holdfast?

I have one. I don't use it for woodworking. That's more for automotive work and cost about the same as a holdfast

[Jim Koepke]

I just got to thinking - has anyone tried a 2 pound brass mallet? Seems like it would pack a punch without causing a dent or bur on the holdfast?

What about the mallet? Could it dent from the holdfast?

My biggest question in all of this is what is wrong with hitting a holdfast with a wooden mallet?

jtk

[Frederick Skelly]

What about the mallet? Could it dent from the holdfast?

My biggest question in all of this is what is wrong with hitting a holdfast with a wooden mallet?

jtk

Bet you're right Jim - the holdfast probably will ding the brass mallet.
Nothing wrong with using wood mallets at all. Was just a thought. :)

[mike stenson]

What about the mallet? Could it dent from the holdfast?

My biggest question in all of this is what is wrong with hitting a holdfast with a wooden mallet?

jtk

It'd get ruined a breakneck speed compared to the holdfast. Use what you want, it's not going to break it anyway.

[ken hatch]

It'd get ruined a breakneck speed compared to the holdfast. Use what you want, it's not going to break it anyway.

Mike,

Ain't that the truth :p. I've had a hard time controlling the snark with this thread. Worry about hitting a holdfast with a metal hammer, I don't think so because first if you use a metal hammer it takes less force to set the holdfast. Second if a metal hammer damages the holdfast it, the holdfast, isn't worth having. I use whatever hammer/mallet is at hand to set my holdfast. They all work but the lump hammer works best.

ken

[mike stenson]

Well Ken,

On the plus side, between this and the other mallet thread, I'm gonna make a green Mesquite mallet one of these weekends.

[Jim Koepke]

It'd get ruined a breakneck speed compared to the holdfast. Use what you want, it's not going to break it anyway.

My wood mallets hit holdfasts and haven't had a problem yet. It may be my holdfasts are different:

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The flat bar top has more springiness than a solid rod with an arc.

It is also likely to be less shock to the face of a mallet than a rod would be.

These were holdfasts made by Harry Strasil, AKA Junior, may he be resting in peace.

jtk

[Dave Zellers]

Well I have to come clean and admit all this runs counter to what I would have expected to hear. Very interesting to say the least. I have always gone out of my way to get my wooden mallet every time I use my Grammercy holdfasts. I’ll probably continue to do so but now for a different reason. I don’t think I’d like the sound of metal on metal.
But wow, I just assumed striking it with a metal hammer would be bad for it in the long run.

[michael dilday]

I also have the Grammercy holdfasts and generally don't use a steel hammer to set them. This hammer is made by Estwing and is about $15 at the orange box store. It seems to be a good compromise between steel and rubber or wood.

Yep Kris I love that mallet. One side is rubber for pounding wood and the other hard plastic for chisels and such. I got rid of all my rubber mallets.

[chris carter]

I use my wooden mallet because
a) it's already there. Why go through the trouble of getting a different mallet for such a mundane purpose? Or why keep an extra mallet in my tool tray? I just keep two strikers - the wooden mallet and the tiny brass plane hammer.
b) Experimenting with using a metal hammer or mallet was not fun on my ears. I use my ears for work so this was a no go.
c) Further, experimenting led me to discover that the wooden mallet worked better. I think this has to do with the fact that the metal hammers would rebound quickly whereas the wooden mallet has significantly more contact time with the holdfast. In other words, I found a metal hammer inferior for the purpose.

[Nicholas Lawrence]

I used one of those combination plastic/rubber mallets the first year or so I was doing this. The plastic side eventually broke. I like the hardwood mallet I made a lot better, but when I was starting out I did not have a hammer and that combination thing worked for a good while.

[bill epstein]

3 Pages of what to hit a piece of scrap steel with? Seriously? I just use whatever's handy, sometimes the cat.