NEW! Faster Search Option

Trestle table design and finishing

Trestle table design and finishing (post #92595)

jscharver on Wed, 10/14/2009 - 13:17

The Archives

I'm building a 68 x 42 trestle table with breadboard ends from SPF. Because of the table width I plan to use 2 legs and trestles for added stability; each component is 5"w x 1 3/8"t. I plan to set each set of legs 12" from each end for knee room. Can I also space them 12" in from each side of the table without compromising the stability? The table top is a glued up panel consisting of 6 pieces each 7" wide.

The piece will be finished with an oil-based gel stain (General Finishes or Bartley). Can I apply water-borne poly directly to this or will I need to topcoat it with Zinsser Seal Coat (1# cut or 2#?)? Could I use an oil/varnish poly mix instead without needing the shellac sealer?

(post #92595, reply #1 of 7)

by JohnWW in reply to jscharver [original] on Wed, 10/14/2009 - 14:21

The bottoms of the trestles should be only a couple of inches shorter on each end than the width of the table, in your case the bottom crosspieces should be around 38 inches wide. The verticals can be in a foot as you planned but as you come in the leverage forces on the joints get worse so sturdy tight construction is a necessity.

John White
Shop Manager for FWW Magazine, 1998 to 2007

John White Shop Manager for FWW Magazine, 1998 to 2007

(post #92595, reply #2 of 7)

by jscharver in reply to Anonymous [original] on Wed, 10/14/2009 - 22:50

John,

Thanks for your advice and prompt reply. I have another question about the construction. I'm planning to have the horizontal beams which connect the legs protrude about 3" beyond the legs at each end. Instead of a vertical wedged/tapered pin through a mortise I'd like to horizontally drill the beams with a Forstner bit and tap in a 3/4"-7/8" diameter hardwood dowel to pin them in a T shape. Is that bad or good and why? End checking or splitting a problem with that approach?

By the way, I built my new-fangled workbench about 2 1/2 years ago based upon your conceptual plans and the video. I love it! It seems like I'm always finding new ways to adapt it to my needs as a pretty novice woodworker.

Thanks again.

(post #92595, reply #3 of 7)

by JohnWW in reply to Anonymous [original] on Thu, 10/15/2009 - 13:45

Good to hear you are finding my bench works well. I'd appreciate any ideas you have for improving the design or new uses or accessories you have come up with. I'm hoping to build an updated model in a year or so.

I'm not sure the pin idea is the best approach for a few reasons:

The joint will have a lot of stress on it at times and that will probably distort the pin or the wood on the sides of the hole, once that happens the joint and the table will get wobbly which will cause even more damage to the joint.

If the pin is a tight fit, which it will have to be, it will be difficult or impossible to remove. This may not seem important now but if you ever want to move the table to new location the ability to disassemble the trestle is really useful.

If you still decide to use a pinned joint use two pins, the mechanics are better.

John White
Shop Manager for FWW Magazine, 1998 to 2007

John White Shop Manager for FWW Magazine, 1998 to 2007

(post #92595, reply #4 of 7)

by Jimma in reply to Anonymous [original] on Thu, 10/15/2009 - 13:58

Regarding trestle table design (not to hijack the OP question), what is the best way to fasten the legs to the top -- screws? Or, if anticipating a knock-down design to facilitate eventual moving of the table, some kind of heavy cleat mounted to the underside of the table with bolts or screws through it to fasten the trestle legs to the cleat?

(post #92595, reply #5 of 7)

by JohnWW in reply to Anonymous [original] on Thu, 10/15/2009 - 17:24

I would definitely design the table so that the top could be separated from the base. There are a number of ways to do this, some are more elegant than others. The attachment also has to allow for a considerable amount of of wood movement.

John White
Shop Manager for FWW Magazine, 1998 to 2007

John White Shop Manager for FWW Magazine, 1998 to 2007

(post #92595, reply #6 of 7)

by Jimma in reply to Anonymous [original] on Thu, 10/15/2009 - 18:13

Thanks, John. I'm leaning toward using L-shaped cleats with screws into the underside of the top.

(post #92595, reply #7 of 7)

by jscharver in reply to Anonymous [original] on Thu, 10/15/2009 - 22:37

John,

Thanks for the double pin suggestion. Vertical tapered mortises through a 5" wide SPF board with tapered wedges are out of my league at this point, but I'm open to suggestions as to exactly how to do it. I'd have to practice a bunch on some scrap.

Here's my plan for affixing the vertical legs to the table top: They won't be attached per se. Instead I'll have a pair of 3"w x 1 1/2t cleats on the inside and outside of each leg pair (these are part of the table apron of sorts). The legs are each 5"w and they'll be fastened to this "sandwich" with two (2) 1/4" bolts in each leg. Then there will be two pieces running the length of this span with a M&T to tie this rectangular apron together. This contraption will be fastened to the table top with cabinemaker's buttons (this is new to me) in order to allow the top to float and expand/contract as needed. I think the twin trestles will lock this in from end to end.

Critique and suggestions are welcomed and appreciated. Maybe other contributors will also benefit and learn from the process.

Thanks again.