Thread: Home-built vises Part 1

I am watching this thread with interest and like the testing strategy,

I was wondering if there is a point of failure on the shafts after multiple binds to the same points of contact, if the head of the duck was tapped and a die used on the shaft, after progressive wear, you could screw the shaft further up or down, changing the point of impact. This would also make replacement of the shaft or head without losing the whole piece (and make them easier to mail out). The holding power of wooden screws seems renound (am not sure if you'd chip the thread or not)

Originally Posted by fields

I am watching this thread with interest and like the testing strategy,

I was wondering if there is a point of failure on the shafts after multiple binds to the same points of contact, if the head of the duck was tapped and a die used on the shaft, after progressive wear, you could screw the shaft further up or down, changing the point of impact. This would also make replacement of the shaft or head without losing the whole piece (and make them easier to mail out). The holding power of wooden screws seems renound (am not sure if you'd chip the thread or not)

It's not a bad idea, except that I don't think it will work .

My reasoning is that the weak link in a wooden holdfast is to my mind the shaft. Even in steel, once something is threaded it is considerably weaker than the original solid form. Whilst, as Ian says, threads have considerable strength; surprising strength in fact, that is in tension. Any bending moment applied to the side of a thread will soon show it's shortcomings.

As you may have seen in the pix already posted considerable bending of the wooden shaft occurs.

Regards
Paul

Originally Posted by FenceFurniture

Am I talking through my hat here?? Am I missing something?

Then, extending the idea, I could have a length of track running along the front Apron and stretcher (which would have to be co-planer), and also up the front legs. There would have to be provision made for some short pieces of T section "exit track" particularly for the legs. This is with a view to eliminating the Leg Vise, but of course I would still have a Face Vise.

Waddyez think?

I think that as usual you have outdone yourself and been you usual ingenious self. Having seen how you set up your workshop to maximise the limited area I'm sure the systems you pictured would be excellent.

However, I'm hoping Berlin doesn't see this as his concept was to make something out of nothing. He is probably in overload right now or frantically painting another of his fabulous canvases to earn enough to buy the components for your systems .

I think his total expenditure would have been measured in farthings (glue only).

Nevertheless I am sure that IanW will see this in the general context of the thread .

Regards
Paul

Originally Posted by derekcohen

Hi Ian



If you treat the wooden holdfasts here as you would a metal type, I am certain that they will not hold up for long. Wacking the rear of the holdfast will stress the intersection with the dowel shaft, the short grain is likely to give way. You method of tapping from below the bench seems intelligent, but hardly the thing for a good WA boy to do! All that bending upsidedown is likely to upset the gizzards somewhat, and then I'd be forced to lie down and miss my woodworking!

Anyway, just because I am analyising the design does not mean that I do not consider that this concept lacks merit. I think that this is a great opportunity to invent something new!

So I did put on my WA thinking cap and came up with another idea: why not make a one piece wooden holdfast with all the grain going in the correct direction? To do this we would either have to bend the wood or laminate it into shape. I decided to do the latter.

I built a form from some scrap MDF.

Derek

I believe the shaft is the weak link in the timber holdfast design. It is only 3/4" and subject to huge bending moment. On the other hand the beam is twice as thick and twice as deep and if the dowel is placed at an angle as with Ian's design there is minimal short grain.

I did a little more testing on the version I re-drilled and placed the shaft at an angle. I overdid the pressure and the shaft cracked, but I have to say the timber I used was defective and I think it had a hairline crack. The beam definitely has two cracks in it. One of the cracks you can see in the pic below. The point is the beam doesn't even remotely look like failing, but the shaft did fail.

I think a refinement would be to use a steel rod in place of the timber shaft.

Holdfast destructive testing 006.jpgHoldfast destructive testing 001.jpgHoldfast destructive testing 005.jpg

I did some more testing with the Gramercy holdfast and the scales. I attached two enginer's clamps and increased the pressure. I heard a click and when I looked at the scales it only showed 15Kgs. Then I realised it had gone right around the clock and was in fact registering around 130Kgs plus. I was about to break the scales!

I backed it off and this is the result below. Impressive. I love those clamps and so simple.

Holdfast destructive testing 004.jpgHoldfast destructive testing 002.jpgHoldfast destructive testing 003.jpg


On to your idea which I think is also excellent. I think the combination of angled shaft in the hole and spring from the lamination will give really good grip.

One point I should mention is that the shaft does not have to be smooth. In fact it is better left rough. I suspect Gramercy only polish the shaft on their product for buyer appeal as they recommend that it is roughened up with coarse sandpaper in a circular direction.

I will look forward to your results.

Regards
Paul

Coincidentally, here is another option, one that was posted on the Old Tools site ...

While browsing the discount rack at Bunnings (my local big box) a week
ago, I picked up a handful of half-price Dutch pins. From their
appearance, I thought they might work as holdfasts.

Never heard of 'em before, but apparently they're used in brickwork --
and a quick Google suggests that their useage certainly **looks**
holdfast-like.

I wasn't sure if I should post this - it will just add another option to Brett's growing list!!!!

At the end of the day, I anticipate that steel is best. Reliable and enduring.

Regards from Perth

Derek

Derek, I love the idea and look of your laminated duck (the perfect name for these things ) but I'm pretty confident that the simple post and beam model, when the angles and dimensions are refined, will do it's job for yonks.

I'm not near my tools at the moment so I can't make the 'improved' version I have in mind but as soon as I get a chance I'll throw my version 2 on the growing pile.

Brett! What are you making with all those hold downs, a hover board?! Cripes

Actually I do seem to have rather a few toggle clamps. In fact with the new Bessey I don't seem to use the Good Hand toggles at all these days so I reckon I'll sell a few. There's no comparison with the speed of operation. The GH are more suited to repeating the same thickness, such as in a jig, because they are fiddly and slow to get to the right thickness/pressure.

Anyway, I'll wager that Derek has more Smoothing planes than I have toggles.

Originally Posted by Bushmiller

.

However, I'm hoping Berlin doesn't see this as his concept was to make something out of nothing...

I think his total expenditure would have been measured in farthings (glue only).

Yep, rule three, subsection four of my manifesto... "no money shall be spent on a tool that could be hand made if the functionality of the self made version is at least 30% of the bought version and takes an appropriate amount of time to make. To determine 'appropriate build time' refer to table 3.4.1 in Appendix B...."

Not to mention the rule about Farthings being kept for the purpose of paying 'The Piper', 'The Ferry Man' or mime artists.

Originally Posted by FenceFurniture

...... Anyway, I'll wager that Derek has more Smoothing planes than I have toggles....

I reckon you'll need to offer pretty long odds to get any takers, Brett!

Originally Posted by Berlin

Yep, rule three, subsection four of my manifesto... "no money shall be spent on a tool that could be hand made if the functionality of the self made version is at least 30% of the bought version and takes an appropriate amount of time to make. To determine 'appropriate build time' refer to table 3.4.1 in Appendix B...."

Not to mention the rule about Farthings being kept for the purpose of paying 'The Piper', 'The Ferry Man' or mime artists.

.

Regards
Paul

I've been using my wooden 'bench ducks' for quite a while now, and I have to say I'm very happy with what they can do. I didn't expect too much from them, but they have managed to cope with all the demands I've put on them.

My main concern in the beginning was the 3/4 inch shaft; I thought that would be the most likely failure point, so I prepared a couple of 1 inch replacements to substitute when that occurred. There have been no failures at all there, so I think I will stick with the 3/4 inch jobs for now.

Derek Cohen raised a concern about the ends of the clamping arm being able to tolerate the whack to loosen them. He was on the right track, but I don't think it was the loosening wallop that caused the problem. Two have developed vertical splits that open up a bit when knocked down. I think it's a combination of the dicey wood I used and not allowing enough wood behind the hole to receive the shaft. The shaft hole is a very significant proportion of the width of the arms on my prototypes.

I had occasion to make some more for a new bench I've just constructed, so I took the opportunity to put what I've learned into practice, to see if I can improve on the prototypes. This time, I used Spotted Gum for both the arm & shaft for 3 of them, and River oak for the 4th (just to see how it goes). I extended the backs of the arms about 25mm more, to give more beef to the areas that get whacked with a mallet during use (original in front, new behind): Old & new.jpg

Because S.G. is so much harder than the previous wood I used, I reduced the thickness of the 'beak' a little. The angle between the axis of the arm and shaft that seemed to work best on the prototypes was about 70 degrees - it's not all that critical, 4 or 5 degrees either way doesn't seem to make a huge amount of difference, but 20 seems to be a sweet spot that allows easy locking when belted down, and easy release when whacked from the side. These are the dimensions I decided suit my needs best: Duck dim.jpg

So far, these have done everything I have asked of them. I use them in situations where moderate to medium pressure will suffice, but they can generate quite an impressive amount of pressure. I haven't gone easy on them, because I wanted to see just how much abuse they can cop, but haven't destroyed any, yet! For my purposes, they are preferable to steel holdfasts, because they are very unlikely to mar surfaces more then very superfically. They can be made in a few minutes each, so wrecking one isn't going to be a big deal, if it happens. I actually put a lot more effort into today's crop, because this time, I expect them to last quite a while, if my 'improvements' really are that....
Ducks inna row.jpg

Cheers,

Update: I'm using my moderator's privilege to update this post after the wooden ducks have had a decent test period. A pair of the ducks pictured have seen steady use for almost 10 years now & have done great service. I haven't treated them with kid gloves, I took the attitude that they cost nothing but a bit of time to make, so if they broke I'd just replace them. So far that hasn't been necessary despite occasionally needing to bash them down pretty tightly. I especially like the broad contact area, they can be used on softer woods like cedar without bruising the surface (as long as you don't go too wild with the mallet!). Wood can be tough stuff....

Brilliant! If I ever get within cooee of my tools again I will make some to your plan, Ian. I'll make the bench too for that matter, right after I build a workshop for it to go in... after my anticipated lotto win.

I'm glad to hear they stand up to abuse because they look great.
Cheers
Matt

Originally Posted by Berlin

Brilliant! If I ever get within cooee of my tools again I will make some to your plan, Ian. I'll make the bench too for that matter, right after I build a workshop for it to go in... after my anticipated lotto win.

I'm glad to hear they stand up to abuse because they look great.
Cheers
Matt

Doesn't the house take precedence at the moment, Matt?

I wouldn't say they cop abuse, but moderately heavy usage seems to be ok. I was using the new ones a lot yesterday & they were performing extremely well. I don't know why, exactly, but the new ones work better than the old, in that they lock down more easily & hold even more firmly than the prototypes - possibly due to the heavier & more solid head. My sincere thanks to you & Paul, for the initial idea, again...

Cheers,

Yeah, the cabin is priority 1-ish. Work keeps cropping up and slowing that down though. I can at least day dream about a new bench can't I? Don't take that away from me!