A new Woodworking bench . . . the story continues . . .

[Alan in Little Washington]

Way back in Sept '07, at the end of a thread about my tablesaw, I said that I was going to follow Monty's lead and my next project was to build a relatively traditional woodworking bench, also based on the design by Lon Schleining which was first published in FWW a few years ago (see the copy on my extension table). However there was always something with higher priority, and I never got around to it.

Then, last December, while working on my second adjustable height assembly (for a magazine article), I wondered if the adjustable legs I designed and built for those tables could be adapted to a woodworking bench such that the bench would be strong and stable and still be adjustable.

I broached the subject here and posted a few SketchUp drawings of the leg design. A few of you pointed out the location of the stretchers on the initial design would likely make it difficult or impossible to lift the top to adjust the table height.

I subsequently changed the location of the stretchers from the fixed legs to the adjustable legs.

Since I already had an indexing jig set up to cut the leg notches for the assembly table legs, I decided to make the woodworking bench legs at the same time using some beech I had sitting around the shop- that was nearly 7 months ago. This Spring I picked up a 30" x 72" x 2.75" maple top from Bally Block, then on a trip to Raleigh last month I picked up a few more pieces of beech at Klingspor, so finally, almost two years after having made the decision and 7 months after actually cutting the first pieces, I had all the materials (and made the time) to actually start working again the new bench. I didn't take any in-progress shots, but here are some pics of the nearly completed adjustable height trestle base with top installed. I still need to add maple aprons, 3 vises (QR front vise, sliding tail vise, Veritas twin screw tail vise), and bench dog holes.

Revised SketchUp drawing. (minus ratchet arms and release cords). Unlike my assembly table legs which stay together by sliding dovetails, these legs mate with a "V" and "V groove". The ratchet arms draw the leg halves tightly together and keep the matching "V" profiles solidly mated.

Side view of the new bench in its lowest position (top is 30-1/2" high)

End view showing top and bottom draw bored tenon pins on legs and wedged through tenons on stretchers.

Close-up shot of ratchet arms (minus release cable) and stretcher tenons.

Side view of bench at full height of 43-1/2"- the height can be adjusted in 1" increments.

End view at full height.

3/4 view at full height

The height adjustment mechanism works very, very, well (as good or better than the ones on the assembly tables). The bench is very sturdy, stable, and does not rack. While heavy, it lifts fairly easily -obviously one end at a time. I need to do some design work on the release cords because the legs are closer together than on my assembly table and there isn't enough side pull on the cords to release the ratchets properly. I have a few ideas, and it will come down to what looks and works the best.

 

[SteveHall]

Alan, impressive! I love how you explore ideas and follow them through design to construction. Wood is such a great medium for testing mechanical concepts isn't it?

A big picture kind of question--why a ratchet system instead of a screw system? I'm imagining a four post version of the two screw Veritas vice, all chained together so one crank turns them all. (Except in very large diameter wood screws to minimize lateral motion.) Wouldn't the larger amount of bearing surface possible in a screw yield better sturdiness than the four tiny points of a ratchet?

Again, thanks for keeping the window open to your shop of inventions.

 

[McRabbet]

Alan, since you don't show the pull cords in your pictures, I'm going to make a guess at a solution that also keeps your hands free from them while you raise the bench top. Could you add a horizontal member just below the the ends of the ratchet arms and then mount a pair of sheaves side-by-side near the center of that member on the inside. The release lines could pass from the ends of the ratchet arms over the sheaves and down to a pedal on the floor. A spring on each ratchet arm would engage the ratchet arm back into the leg notches. That would give you a foot-powered, hands-free release. Just my .02

 

[WoodWrangler]

Sweet! That turned out AWESOME!

 

[Trent Mason]

Nice work Alan! Can't wait to see the final product. :icon_thum

 

[Alan in Little Washington]

Alan, impressive! I love how you explore ideas and follow them through design to construction. Wood is such a great medium for testing mechanical concepts isn't it?

A big picture kind of question--why a ratchet system instead of a screw system? I'm imagining a four post version of the two screw Veritas vice, all chained together so one crank turns them all. (Except in very large diameter wood screws to minimize lateral motion.) Wouldn't the larger amount of bearing surface possible in a screw yield better sturdiness than the four tiny points of a ratchet?

Again, thanks for keeping the window open to your shop of inventions.

There was a pic of a bench like you describe in Lon Schleining's book, but I can't see how it would ever be very stable. The top was supported by four lead screws. and there is absolutely no way to brace such a rig. With my ratchet and pawl system, the weight of the table and angle of the ratchet arms pulls the mating leg halves tightly together and makes for a very sturdy, steady, and rigid table. The more weight, the tighter it gets.

Alan, since you don't show the pull cords in your pictures, I'm going to make a guess at a solution that also keeps your hands free from them while you raise the bench top. Could you add a horizontal member just below the the ends of the ratchet arms and then mount a pair of sheaves side-by-side near the center of that member on the inside. The release lines could pass from the ends of the ratchet arms over the sheaves and down to a pedal on the floor. A spring on each ratchet arm would engage the ratchet arm back into the leg notches. That would give you a foot-powered, hands-free release. Just my .02

Rob, you either remember my assembly table or we think alike. I plan to do something very similar to what you describe. I may just go with a thin wire between the free ends of the ratchet arms, with a bungee attached in the middle that runs down to the foot pedal or visa-versa. It doesn't need to be strong, but it must give so you don't break the cord when you step on the pedal, and I want it to be light so the arms will re-engage by gravity without the need for springs- trying to keep it simple, or at least no more complex and to retain some of the traditional look. I still haven't decided on a pedal and mount yet.

 

[woodguy1975]

Hey Alan, as always nice work. I think your design is really creative, but I do have one question though concerning the short grain of the V notches and overall durability. Have you subjected this type of system to an impact force on the top. I wander if you had the table raised and were chopping a mortise or dovetail if the grain would fail under the impact.

I think about chopping half blind dovetails. You cut out the back side and then wack the ramainder to split it off. I wonder if this same kind of thing will be an issue long term....

Really think it is a cool design. I could see this system with Aluminum notched side plates for each leg being a real contender for adjustable bench kit. If I still had a shop I would really consider building one to match with legs laminated from maple and aluminum.

John

 

[Alan in Little Washington]

Hey Alan, as always nice work. I think your design is really creative, but I do have one question though concerning the short grain of the V notches and overall durability. Have you subjected this type of system to an impact force on the top. I wonder if you had the table raised and were chopping a mortise or dovetail if the grain would fail under the impact.

I think about chopping half blind dovetails. You cut out the back side and then wack the ramainder to split it off. I wonder if this same kind of thing will be an issue long term....

Really think it is a cool design. I could see this system with Aluminum notched side plates for each leg being a real contender for adjustable bench kit. If I still had a shop I would really consider building one to match with legs laminated from maple and aluminum.

John

I haven't had any problems with the leg notches on my assembly tables- either wailing on it, standing on it, and even jumping on it with my dainty body (200 +/- lbs). The ratchet pawls are 1/2" in diam., the notches are 3" wide, and the direction of the stress from the pawl is not a 90 degree shear, it is at 45 degrees towards the center of the leg. I think they would take an really incredible amount of stress before they would ever fail - it may not even be possible. Time will tell.

Besides, if I used metal it would be too much like the commercial "Adjusta-bench". :wsmile:

 

[woodguy1975]

Besides, if I used metal it would be too much like the commercial "Adjusta-bench". :wsmile:

That is very true. :gar-Bi

 

[Robert]

That's a really great idea well executed in a table. You've dubbed it as an "assembly" table, but in your opinion, could it be used as an outfeed table as well. Since the leg adjustment is in 1" increments, maybe a type of screw adjuster on the feet for microadjusting the height to match a tablesaw would be in order? (similar to that found on appliances.)

Thanks for the photos and when did you say the kit would be available?

 

[ErnieM]

Alan - As usual, I understood little of what you said, but then again, I just barely understand how a retractable ball point pen works. That said, I remain amazed at your creativity and craftsmanship. And how much could I use an adjustable work table like that?!!
:notworthy: :notworthy: :notworthy:

Ernie

 

[Alan in Little Washington]

That's a really great idea well executed in a table. You've dubbed it as an "assembly" table, but in your opinion, could it be used as an outfeed table as well. Since the leg adjustment is in 1" increments, maybe a type of screw adjuster on the feet for microadjusting the height to match a tablesaw would be in order? (similar to that found on appliances.)

Thanks for the photos and when did you say the kit would be available?

The assembly tables I was referring to were the one I built a year ago and a second one I built this winter for a magazine article which should be out later this year. My latest creation pictured in this thread is a woodworking bench- different animals.

Here is the link to a thread about my first assembly table- link 1, link 2

Other than this shot of the second assembly table headed out of my shop I didn't post any pics of it because it is the subject of an article scheduled to be published in American Woodworker magazine this winter. There will actually be two articles with photos, dimensions, and instructions how to make the adjustable legs and the torsion box top.

Second assembly table headed out the door:

I've got plenty of real estate on my saw so don't need any more outfeed or extension tables:

 

[Alan in Little Washington]

Alan - As usual, I understood little of what you said, but then again, I just barely understand how a retractable ball point pen works. That said, I remain amazed at your creativity and craftsmanship. And how much could I use an adjustable work table like that?!!
:notworthy: :notworthy: :notworthy:

Ernie

Yes, but I can't tell a double Flemish from a ***** Tonk. When are you starting the next masterpiece?

If you really want an adjustable work table we might be able to work something out.

 

[ErnieM]

Yes, but I can't tell a double Flemish from a ***** Tonk. When are you starting the next masterpiece?

If you really want an adjustable work table we might be able to work something out.

If you could tell the difference between a double Flemish and a ***** Tonk, what good would it do you? I'd rather be able to design a great workbench. Unfortunately, I don't think the adjustable bench would work for me because I store what little wood I keep on hand in my workbench.

As for my next "masterpiece", I'm currently building a tv cabinet for my covered porch. I may be able to build a harpsichord but building a square box is taking forever - and that's without dovetails. :gar-La;

Ernie

 

[timf67]

I noticed that you mentioned bally block as the supplier for you bench top. I too got a bally block top - best decision I made when I made my bench:

Anyway I did my skirt in walnut. I also noticed that your trestle legs are similar to mine, so I will tell you my big mistake so you can avoid it - though your height adjustment should help you here. When I laid out my dog holes I didn't consider the position of the top stretchers under the top, so now the bottoms of my dog holes are partially blocked by the stretchers! :BangHead: Oh well, it still works great even with the poorly thought out design.

 

[Alan in Little Washington]

When I laid out my dog holes I didn't consider the position of the top stretchers under the top, so now the bottoms of my dog holes are partially blocked by the stretchers! :BangHead: Oh well, it still works great even with the poorly thought out design.

I shouldn't have any trouble with the stretchers since they are below the cross member at the top of the legs- and 3" below the bottom of the bench. I'll need to plan around the cross members though and will also likely need to notch at least one on them for the end vise. The top is just attached with one lag bolt through each cross member so I can still adjust it.

Nice looking bench. I have some walnut and Ipe, but think I will use the rough maple Russell at Bally sold me for the aprons. What did you use for a finish?

 

[timf67]

I shouldn't have any trouble with the stretchers since they are below the cross member at the top of the legs- and 3" below the bottom of the bench. I'll need to plan around the cross members though and will also likely need to notch at least one on them for the end vise. The top is just attached with one lag bolt through each cross member so I can still adjust it.

Nice looking bench. I have some walnut and Ipe, but think I will use the rough maple Russell at Bally sold me for the aprons. What did you use for a finish?

Thanks for the compliment. I used a homemade blend of BLO, mineral spirits, and beeswax. I make a homemade mineral oil and beeswax finish for my cutting boards, and after reading a few books and posts about workbench finishes I made up some BLO/turpentine/beeswax and it worked great - though my wife didn't appreciate the house smelling like turpentine! :nah:

You mentioned lag bolts as your method of anchoring the top. Since the top is so heavy - especially once you add the aprons and vises, you really don't need lag bolts. I opted for 1" diameter rounded steel locating pins mounted in the base with 1" steel bushing mounted in the top. So my top basically just "sits" on the legs which makes it easy to breakdown if I ever need to move it.

 

[Alan in Little Washington]

Thanks for the compliment. I used a homemade blend of BLO, mineral spirits, and beeswax. I make a homemade mineral oil and beeswax finish for my cutting boards, and after reading a few books and posts about workbench finishes I made up some BLO/turpentine/beeswax and it worked great - though my wife didn't appreciate the house smelling like turpentine! :nah:

You mentioned lag bolts as your method of anchoring the top. Since the top is so heavy - especially once you add the aprons and vises, you really don't need lag bolts. I opted for 1" diameter rounded steel locating pins mounted in the base with 1" steel bushing mounted in the top. So my top basically just "sits" on the legs which makes it easy to breakdown if I ever need to move it.

I was reading Lon Schleinling's article again and think he may have used a similar finish.

I need the two lag bolts because I must lift up on the top (and upper leg sections) to change table height. I used one lag bolt up thru the bottom of each cross member into the center of the top, so don't need to worry about seasonal movement.