Yet another workbench top question

[Doug Shepard]

that I haven't been able to find an answer to searching past threads. I'm sure it's here somewhere, I just haven't found it. If gluing up a workbench top, is there a stability concern using 8/4 vs 4/4 hardwood? I'm planning on face gluing up a top 4" thick with the board edges being the top surface. I can get European beech for about $2 less per B.F. than hard maple but they only have 8/4 or 4/4. If I go with the hard maple, I was planning on getting 5/4 and resawing/planing it to 1" finished thickness after jointing. The wood movement would seem to be in an up/down direction rather than side/side where using narrower stock with alternating growth rings for stability is a plus. The 8/4 would also cut down the amount of glue-up I have to do, which is a plus. I'd probably shoot for a finished thickness of 1-3/4" if I go that route.

And regardless of the answer to that question, do I need endcaps? The RH end will have one as it's also the rear jaw for the LV twinscrew, but what about the LH end? Visually an endcap would look better than end-grain, but do I need one for top flatness reasons?

[Bob Smalser]

... is there a stability concern using 8/4 vs 4/4 hardwood? I'm planning on face gluing up a top 4" thick with the board edges being the top surface. ...planing it to 1" finished thickness after jointing.

The wood movement would seem to be in an up/down direction rather than side/side where using narrower stock with alternating growth rings for stability is a plus. The 8/4 would also cut down the amount of glue-up I have to do, which is a plus. I'd probably shoot for a finished thickness of 1-3/4" if I go that route.

And regardless of the answer to that question, do I need endcaps?

Assuming you are lamming flatsawn boards, the top will move seasonally in both directions, just twice as much vertically as horizontally. You still have to soft mount the top to the frame if you expect it to remain flat.

In any lamination, the more glue joints, the less force of seasonal movement and the less likely one of the gluejoints will break. The top will also be stronger and slightly more stable because of less continuous grain and all those glue joints sealing the wood. 1" lams are ideal. 2" lams are much less so.

You'll need an endcap to mount an end vise. Soft mount the endcap using a sliding dovetail or a rabbet or groove pinned only in the center of the top.

[Doug Shepard]

Bob
Thanks. Think I'll just stick with the maple and the original idea of planing 5/4 down to 1".

[Michael Hammers]

How in the world do you make a sliding dovetail for something that thick? It seems I have only seen one done with wood up to about an inch?

[Bob Smalser]

How in the world do you make a sliding dovetail for something that thick? It seems I have only seen one done with wood up to about an inch?

Easy and done every day. 3 1/2hp Router and straight edge.

And of you insist on doing it by hand, do a T&G instead and pin it in the center.

[Doug Shepard]

...
In any lamination, the more glue joints, the less force of seasonal movement and the less likely one of the gluejoints will break. The top will also be stronger and slightly more stable because of less continuous grain and all those glue joints sealing the wood. 1" lams are ideal. 2" lams are much less so.
...


I got thinking about this a bit more (that's always dangerous) and wondered about using Baltic Birch ply for a bench top. Not laminated together flat, but cut into 4" strips, laminated, and stood on edge with the plies visible as the top surface. You'd have to stagger the butt joints from layer to layer to get past the 60" limit on the BB ply but I wouldn't think you could get much more stable than that. And it would probably be plenty heavy. Maple or hardwood would certainly look a lot nicer and I'm not sure I'm seriously considering this, but I played with a calculator to figure out what would be required, and it comes out to a little less than 4 sheets for a 26x84 top. That would work out to about 1/3 the cost of doing one in hard maple.
Didn't somebody here at SMC do somethng like this a while back? I haven't been able to find it if so. This certainly wouldn't look traditional, but I'm just thinking out loud here a bit. Anyone seen a benchtop made this way?

[Michael Lutz]

I think it was sam Blanco that made that bench. I ran across it from the links/Reviews page at Adjust-a-bench.

Mike

[Doug Shepard]

Bingo. I found the SMC thread via your Noden clue.
http://www.sawmillcreek.org/showthread.php?t=22081

If it's good enough for Sam, I guess it's good enough for me too.:D
Maybe if I go this route I should name my bench after it's inspirer - maybe call it Son of Sam ??

[Bill Vittal]

There is a good reference to the workbench construction style you are considering starting on page 96 of Scott Landis' "The Workbench Book." The only problem I see with this construction method is flattening the top after all the laminates have been glued up. In Landis' book the workbench builder used a wide belt sander. If you have access to one, then I really don't see any problem with the method.

[Doug Shepard]

Thanks. I have that book but must have missed that page. I'll take a look. It's not free, but when I inquired at my local hardwood place about possibly bringing a wood top back in after glue-up they said no problem. They have a wide-belt I think 30" or 36" but I was only planning 26". I would have probably flattened here with handplanes (maybe with a router sled first) but asked about the wide-belt to see what it would cost. They charge by the time but said it would probably only be around $20 if they didn't have to take a lot off. The more I look at Sam Blasco's thread, the more I like this. I'll check out the Landis book too.

Noden Legs arrived yesterday (caster package on BO though), LV vises got here today, my Jeffers Pet order is due tomorrow (China needs a gloat too:D ), and more Gros-Stabil closeout sale clamps (to help in the glue-up) due in a week or so. Just need to get some wood and/or BB ply.