Workbench frame construction

Workbench bottom side

Dirk Vogel


>And that's what you may see from above. The tool tray is white, the normal bench top (3") light grey, the aprons (6") middle grey, the lengthwise supporting structure dark grey and the crosswise supporting shelves nearly black.

Workbench support scheme

Dirk Vogel


>Now, look at the scheme of my supporting shelves, seen from the short side of the bench :

Workbench's long side

Dirk Vogel


>This is my bench, seen from its long side :

Workbench's short side

Dirk Vogel


>And this is finally the bench shown from its tail vise side. My question is : do you see some kind of error in all this ? I never saw a bench with six legs, but given its extended dimensions, it seemed quite natural to mee adding two legs in the middle. They are 3 1/2" and square for now ...

Thanks for your comments !

Re: Workbench's short side

Joel


>I think that because there are no stretchers, the chances of a design like this rocking is 100%.

Re: Workbench frame construction

thomd coralseacat@yahoo.au


>41" tall, That is 5-10 inches taller than I use, and I'm 6'1", so I;m guessing you are 8-12 inches taller?

That pattern is going to either be a nightmare to level, and or a nightmare to structure.

How much of the Tucker are you inletting into the front. It's not as easy as it sounds to end up making something useable, and you loose the estra clamping length though it seems you have that elsewhere.

Re: Workbench support scheme

thomd coralseacat@yahoo.au


>Just to be helpful about nomencalture: A "shelf" is not really a wood element. It is almost exclusively used to refer to the thing that supports books or other stuff one is storing on horizontal planks. When you are working on a shelf, as a piece of wood in the rough it would likely be refered to as a "plank". About the only place one finds shelves in workbenches is various storage arrangements.

A heavy horizontal structural element usually supported by a post, is called a "beam". Less specifically it may be called a "cross piece" or "cross member". The workbench Book calls these horizontals, "top bearers" which is really not all that helpful though in context it isn't likely to loose too many people.

Re: Workbench's short side

thomd coralseacat@yahoo.au


>It's completely unecesarry and probably a bad idea to have six legs. It takes half of two single posts of softwood, 4 inches square to support 10 feet of external wall on a 2 story house, In other words 16 square inches of softwood to support the wall the roof loads and the weight of all the other chatels and materials, dynamic loads.

It takes a 4x10 beam to support the wall between the posts. So even though your bench is a little long, it a huge beam, if you build it right, and does not require midway support.

The other two things that worry me from what I see is that the legs seem set far enough out that they will be in the way. Most important there isn't anything other than the interlocking of the beam/shelf at the top to stop the legs from racking. Are you planing on a stretcher. In theory you could engage the top of the legs into the benchtop to control racking. You would have to deal with expansion issues and/or the interlocking of the legs that might cut into the struture of the top.

Re: Workbench frame construction

Dave Thompson


>I think you have made more design drawing than anyone I know prior to the first cut. Looks like it will be beautiful though.

I agree with Tom, that 41" seems high. If I remember corretctly, mine is around 35", and I am 6'1". I think it's the perfect height for me to plane wood on.

Regarding the beautiful design. If you make it too pretty, you'll really feel bad the first time you get a gouge, stain or scratch on it. Though I suspect you'll be glad you put forth the extra effort to make it look nice. Mine is just solid maple. if I were to do it again, I would add some contrasting wood aesthetic appeal.

good luck,

Dave

nomenclature (OT)

Dirk Vogel


>Thanks, Thom, for your correction about my poor English. I'll try and learn this beam � shelf � plank story. :-)

So silly of me ... Correction n. 1

Dirk Vogel


>Pardon me everybody ... I did my drawings late at night and forgot the strechers in the low region of the legs. Here you go with the correct version.

After reading Thom's critiques, I fear there must be further corrections about the mortise-tenon-joints ... Look also the following picture, please.

So silly of me ... Correction n. 2

Dirk Vogel


>That would be the other side of the bench.

Thom, you tell me the legs are the sufficient outside to get in the way. My idea was to line them up with the benchtop edges. I saw some of benches with their legs like that (e.g. Landis, p. 25 or 43). I planned also to drill some holes in them, to permit my newly acquired Veritas holddowns to help with edge jointing. Also for this reason I hoped that the third leg may come in handy, because with it maybe the bench wouln'd require a board jack (cf. Sam Allen, p. 76).

Anyway, I'm not attached to that idea, I thought only that the bench may be more stable like that. On the other hand, mortises are going to stick out this way. I'll have to change that ...

Rocking

Dirk Vogel


>Of course ... Please look at my corrections below.

Maybe six legs are overdone ...

Dirk Vogel


>Let's see. If I use only four legs, shouldn't they get a bit more "inside" ? I'll show you below what I mean.

And no, I want my frame decomposable, so I'm not going to engage the top of the legs into the benchtop. The platform should only lay on some upsticking piece of wood of the supporting beams. With its 400 pounds I hope it won't move.

Height � pattern � Tucker

Dirk Vogel


>Bench height : 41" may seem very high indeed. But I already tried to saw and to chop (with chisels) on a bench of 33", and it was waaaaaaaay to low � I had to curb my back quite much, and that pose got me pain. On the other hand, I tried planing on 40", and it went quite well. So that's my compormise ... I'm 6' 2 1/2", by the way.

The dark wood pattern is a pastime, I agree � but perhaps not only that. I thought to cut the wood in the same direction as the benchtop's wood goes, so maybe it is not a nightmare to plane, after all. And sure, there'll be much work involved, especially because I'd like to assemble the dark wood as butt miter joints. But then, maybe another pattern is easier to build � for instance the one below. Anyway, the pattern comes last, if it's coming, and I'm not too concerned about it right now. If I do it, it's to learn ...

The Tucker is let in the top to be aligned with the apron when open. We discussed this topic a bit. I know you're not fond of this idea, Thom, but I think it's convenient to have a workpiece aligned with the apron, too, when fixing it with a vise.

Beauty of benches

Dirk Vogel


>As I stated three months ago, I need a beautyful bench. I'm doing this not only to have a tool at the end. And I'm aware that I'll feel really bad if something wicked happens to the bench. Well, that's the price to pay in this case. Thanks for encouraging me, though ! :-)

Re: Beauty of benches

Greg B�tit, Vergennes, VT.


>That's going to be one nice bench!

If you need someone to make the first dent on the top surface (so that you can start treating it like a tool instead of fine furniture), I'm qualified.

greg

Re: Beauty of benches

Dirk Vogel


>Thanks a lot, Greg, but I fear I'll be qualified to do that on my own ;-) So don't bother ...

4 vs 6 legs

jim reed @ tallahassee


>I like four. It takes three points to define a plane. Four legs mean just one leg (25%) is out of the plane, but six legs means that three legs (50%) are out of the plane. With uneven floors it seems that six legs would always want to rock a bit.

Re: Height � pattern � Tucker

thomd coralseacat@yahoo.au


>The height for planing can vary a lot depending on the kind of tools you have. Wooden planes like The ECE or the English style can have your hand several inches higher than some metal or Japanese models, And of course the workpieces vary in thickness depending on what kind of work you do. The highest bench I have heard of was Michael Fortunes' bench which was designed around 37", mostly for working with routers. Can't recall how tall he is but I think he might be average/tall. The height you have I just can't see getting any weight behind the tools at all. There is a range, but it varies with a range about 6" lower than what you are currently finding comfortable. It can vary with the actuall techniques people use like if you hold a chisel by it's handle or by the blade, you don't what to end up with a bench that only works becaue one has the wrong technique.

I don't mind insertting the vise in the table top. I think one of the earlier drawings had it done in a way that destroyed top structure but the current cut away is no more than the average tail vise and could be accomodated. My only concern is that the bench will move a little and even the jaws are compressible, so getting the exact projection that will allow the workpiece to be supported seems dubious, but as long as it ins't set back it should be fine.

My main concern with the pattern on the top is that if it is venner thin it won't be durable enough, and if the top needs flatening it may be removed in an uneven pattern. Or, if it is the full depth of the top then you get into structural problems because you get interupted grain. If it's crossgrain then it will blow itself appart.

Re: So silly of me ... Correction n. 1

thomd coralseacat@yahoo.au


>I'm not too sure what is happening here at the top, but with stretchers it's likely to work.

I think your stretchers would be stronger if shoulders no wedges were used on the inside. The shorter crossmembers will probably work, the only thing I see there is they look pretty sharp on the shins, but as long as you are prepared for the odd collision and preferably set thme back from the edge...

Re: So silly of me ... Correction n. 2

thomd coralseacat@yahoo.au


>In the two designs you reference, there are only two legs and between those legs the is what we call a kick, or toe clearance. So your bench has a a third leg that means as you work back and for in fornt of the bench both your toes and knees could come in contact with something. And the tenon extentions look really painful.

Almost all benches have some support directly under the front edge, but the sled recesses the posts, and the type of leg on the roubo or shaker benches has a kick.

Re: So silly of me ... Correction n. 1

Wiley Horne


>Hi Dirk,

This bench will be superb, and the more so because of your questioning of all the details.

My comment is mainly to reinforce Thom's point about the stretchers. At 400lb, the bench will be heavy enough to require wide stretchers to prevent lateral movement (rocking, as Joel said) under planing force. Speaking of the stretchers, it is only the shoulders that react lateral movement and make a mortise and tenon joint rigid. So I suggest you make the stretchers at least 6" or 7" wide, with, say, 1/2" shoulders notched into top and bottom. If you decide to use a middle pair of legs, just pass the stretchers straight through these legs.

I learned my aesthetics in the engineering dept., but it seems to me that with all that mass in the bench top, you will want balancing mass down below, maybe 4" thick legs, as well as the larger stretchers. The thicker legs will also make for a more rigid joint against planing force.

Your vise decisions are excellent IMO, and again, I admire your approach to this project.

Wiley