Thread: advice sought: are my legs too big ?

Here's a drawing of the same base with 3 layers of flooring rather than 4. Still has good antiracking.

it's a work bench, not a dining table, so what does it matter if the leg's are "chunky"?

my considerations would be
ease of construction -- "laminated" mortice & tenons are easier to make than chopped out ones
do you have enough of Studley's "reject" material for your design?

The first one will require about 20% more timber. I'm not so much worried about looks as chewing through more than I need to use to get a god rigid base, and also the consideration that I'll be moving at some stage and have to shift it, probably to the NSW south coast. The light version will be about 90 kg.

I was going to do as many mortises as I can by lamination but the front to back ones will have to be cut.

Thank you for your reply.

There are two worlds of thought here; a) you can't over build a bench, and b) apply appropriate quality. I've been laminating flooring for a bench top and this is difficult time cunsuming work. If it doesn't need to be so heavy, save the time and materials. For mine it would depend on what it's purpose is.

Not too heavy. Too many. Four is plenty.
Is this for woodwork or repairing locomotives.
The only function I can see for the intermediate legs is to provide obstructions when you want to stand close to the bench.

Originally Posted by damian

The first one will require about 20% more timber. I'm not so much worried about looks as chewing through more than I need to use to get a god rigid base, and also the consideration that I'll be moving at some stage and have to shift it, probably to the NSW south coast. The light version will be about 90 kg.

will you be hand planing on that bench?
if yes, 90kg might be considered too light -- it depends on the mass of the top
reading about other benches, 150 to 200 kg all up seems to be a sweet spot for bench mass

agree with wizened -- eight legs is four too many
also you might want to allow 2-300 mm overhang each end of the base

racking -- if it becomes a problem -- could be addressed by attaching 18mm construction ply across the back legs -- rather like the back on a cabinet

Thank you for the replies.

It's a general purpose bench, not specifically for planing. To be honest I don't use my hand planes much. I do all I can on my table saw with router wing and incra fence. I also have a thicknesser and drum sander.

I don't have a lot of pieces over 1.2 meters long so there has to be some intermediate structure. I went from 6 legs to 8 to shorten the drawers. The drawers are actually the most important bit for me. I need a bench but I REALLY need storage. My tools are banging around in cardboard boxes and I'm fed up with that..

I am going to panel in the sides and back but I was going to do it with v grooved cut down floorboards and not glue them in.

The laminex front will overhang about 4" in front. Even if I put another top on it it will probably overhang some.

I'll give some thought to the points you've raised. I thought I'd finally got a design I was happy with but maybe I'll have to rethink.

Originally Posted by damian

I don't have a lot of pieces over 1.2 meters long so there has to be some intermediate structure. I went from 6 legs to 8 to shorten the drawers. The drawers are actually the most important bit for me. I need a bench but I REALLY need storage. My tools are banging around in cardboard boxes and I'm fed up with that..

I am going to panel in the sides and back but I was going to do it with v grooved cut down floorboards and not glue them in.

The laminex front will overhang about 4" in front. Even if I put another top on it it will probably overhang some.

I'll give some thought to the points you've raised. I thought I'd finally got a design I was happy with but maybe I'll have to rethink.

Damian,
if you stagger the joints when you do your laminating, you can make beams the length, width and height you need. That is how commercial long span laminated beams (and Ikea solid wood bench tops) are made. The ends of each piece are just cut square across and butted together.

However, with the top I'd be inclined to scarf the ends of neighbouring pieces because I THINK that would make flattening it after glue up a bit easier. Then again, if most of the after glueup flattening will be via a thicknesser, square ends might be just as good.

Given that your primary aim is under bench storage, I'd locate the four legs to create a rectangular void. I'd then fit "kitchen style" cabinet carcasses into the void so I had clear vertical surfaces on which to mount mechanical drawer runners. Mechanical runners will be a real pain to fit into a post and rail structure.

Again thank you for your thoughts.

I should mention I have a number of agenda with this project. Yes it's a bench but it's also an attempt to improve my wood skills with a view to trying some proper cabinet making, and as mentioned storage. Finally I want to use up some of the timber I bought a couple of years back. I'm trying to achieve a few things and making things easy for myself isn't high on the list I'm trying to do a half decent job on the joinery to give me confidence I can attempt more critical projects.

I have considered what you said the other day and redesigned it with 4 legs. Instead of the intermediate posts going to the floor they will be smaller, terminate at the stretchers with an open motise and tennon, or a 2 sided lap if you like, not sure what to call it. Anyway they will disguise the short faces. The inner stretcher lamination which will form the tenons will join at the center half way along the outside laminations.

I was always going to panel in the back and sides, and I designed it so the sides will be flush with the inner faces of the legs. The intermediates will have horizontal stiles, if you like, to carry the runners. I've thickened the legs to 4 laminations, each being 19 mm.

This version should actually be easier to make. I'll laminate up the stretchers and clamp them together before doing the final cuts. That'll make them all identical. Then I'll size up the mortises in the legs to suit. I bought some 8 mm dowel which I'll use to align everything while I'm sorting it out and of course to stop slipping when I'm doing the glue up. That should make it a bit less traumatic.

I went through the pile this morning and selected the timber. There will be a lot of cutting to exclude problem areas in the wood. Lots of voids, knots, splits etc... I'll model up the new design during the week. If your interested I can post pics here including more details than I put up above.

I noticed in bunnings booval:

Aquadhere exterior 4 liters $56. That seems like a decent price to me. Lower prices are often not the beginning....
2.4 x 30 x 70 non structural pine $2.75 each (might be good to laminate up for a bench top for someone ?).
Tas oak dowel was cheaper than clear pine ? 2.4 X 8mm was about 3.88 or something...I found that odd. I would have thought pine would be cheaper ?

Anyway thank you for your thoughts.

Originally Posted by damian

I have considered what you said the other day and redesigned it with 4 legs. Instead of the intermediate posts going to the floor they will be smaller, terminate at the stretchers with an open motise and tennon, or a 2 sided lap if you like, not sure what to call it.

it's called a bridal joint

I've thickened the legs to 4 laminations, each being 19 mm.

This version should actually be easier to make. I'll laminate up the stretchers and clamp them together before doing the final cuts. That'll make them all identical. Then I'll size up the mortises in the legs to suit. I bought some 8 mm dowel which I'll use to align everything while I'm sorting it out and of course to stop slipping when I'm doing the glue up. That should make it a bit less traumatic.

I went through the pile this morning and selected the timber. There will be a lot of cutting to exclude problem areas in the wood. Lots of voids, knots, splits etc... I'll model up the new design during the week. If your interested I can post pics here including more details than I put up above.

except for appearance sake, one of the advantages of laminated members is that many of the timber defects can be left in place -- if one piece has a knot or void in it, gluing good wood either side will render the voiud irrilevant. Afterall your beam is for a bench, not a bridge.

keeping it all aligned on glue up is important but not critical, expecially if you can pass the final assembly through a thichnesser

Originally Posted by ian

it's called a bridal joint

yes, sorry braninfade.

except for appearance sake, one of the advantages of laminated members is that many of the timber defects can be left in place -- if one piece has a knot or void in it, gluing good wood either side will render the voiud irrilevant. Afterall your beam is for a bench, not a bridge.

keeping it all aligned on glue up is important but not critical, expecially if you can pass the final assembly through a thichnesser

I want to avoid defects in the visible faces as much as possible. I'm not worried about internal voids, but there are a LOT of flaws in the timber I'm using. I also want the tennons to be solid.

I hope to clamp the laminations dry, get them right, drill and dowel then use the dowels to locate everything when I add glue. I hops to have enough meat to plane or at least sand the laminations a bit to clean up any leftover glue properly.

I'll try to get the new version modelled up today, but I'm getting a lot of distrations today...sigh.

Regarding dowels for locating your laminations, I've found that the little 8mm and 10mm dowels don't cut it for this work. I had a few move in their holes and misalign the joins by a couple of millimetres. I suspect that the glue provides enough lubrication during clamping that the clamping force can skew the dowels and widen their holes. The last one I did this way used a 19mm dowel, that one was fine.

Was this in hardwood ?

I was wondering about what diameter to choose. I bought the 8 mm because I've got a nice new brad point bit that size, and it seemed a reasonable size. I wonder if there is a rule of thumb for dowel diameter.

Yup, 70 odd year old hardwood flooring. The dowel was just the 8/10mm pre-cut stuff... Harrod's? I don't have any idea on rules for this, but I decided to make sure it wouldn't happen again, hence the 3/4" dowel.