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Susan Lamb
05-17-2015, 12:52 PM
I work in a Seniors Society Workshop where we use shared benches, 8' x 3 1/2'. We are about to replace one with a new roubo style bench. The plan is to have a laminated hard maple top (3 1/2" thick) and a douglas fir base (legs 5 1/2" x 3 3/4").
It's a wide top; to support it we hope 1/3/4" w. x 3 1/2" h. upper stretchers will do the trick.
Two 21" wide benches pushed together is a possibility but requires more wood/expense.

Has anyone else made a wide roubo style workbench?
What other concerns or ideas cross your mind? :confused:

Brian Holcombe
05-17-2015, 1:05 PM
Susan,

Do you often have two people working opposite sides of the same bench?

Susan Lamb
05-17-2015, 1:46 PM
We often have 2 people on each side of the bench. Our exisiting bench allows almost no workholding opportunities: only one vice, no dog holes and almost no clamping (because there is only a 1" plywood overhang over a solid side). Our room is about 16' x 40' with equipment placed all around the perimeter and two shared workbenches (one 8', one 16') in the middle. There is not much hand tool work going on now, but then it is hard to hold work on the current bench.

Andrae Covington
05-17-2015, 2:06 PM
The dimensions of the top of a Roubo style bench make it function like a beam, albeit a very wide but shallow beam. As hard maple has an even higher modulus of elasticity (stiffness) than douglas-fir, it should be quite stout. The span of the extra width is negligible compared to the usual <8' span in length. If you are still concerned about sagging, run a long upper stretcher down the middle, connecting to short upper end stretchers between the legs.

Brian Holcombe
05-17-2015, 2:06 PM
Dogs, fixtures and holdfasts are very helpful. They open a world of possibilities not available to those using only a front vise.

I'd make two narrow benches ahead of one wide one, four people working on the same bench is going to be a trying experience if you start to add work holding devices such as holdfasts, dogs and other fixtures and you'll be dealing with a good bit of wood movement.

Also, working on a 42" x 3.5" x 8' piece of hard maple during the build is going to be hellish.

Jim Koepke
05-17-2015, 2:31 PM
Susan,

Welcome to the Creek. Your information does not indicate a location. Another member near you may have a solution you could visit in person.

My first thought is the benches used in many high school shop classes. They would often have 3 or 4 students working on them at the same time. Of course the ability for multiple people at the same bench depends on the size of the projects being built.

Four people building jewelry boxes would be quite different than four people all trying to build large book shelves.

jtk

Warren Mickley
05-17-2015, 2:37 PM
Welcome to the forum, Susan.

A few notes. The benches in Roubo's work do not have upper stretchers. The legs are tenoned into the top. On some benches the tenons are through tenons, on some the tenons are hidden, a little short of the top. The width of the top can change with humidity swings and not cause great problems. With a stretcher right under the top and a 42 wide inch top, seasonal variation in width is a serious concern.

My preference would be for the 21 inch benches. I have worked with two people on 21" X 8 foot benches; 10 or 12 feet is better. I think you could increase versatility by getting more vises for your existing benches. If they are 42 inches wide you could put one at each corner. You might consider just making one 21 X 96 bench, and keeping both old benches. Then if the new bench is a success, you can make another.

Jim Matthews
05-17-2015, 2:44 PM
If the span is that wide, consider building a torsion box instead.

It will be easier to make, and stiffer. If the top surface is made the same
as the bottom, it can be turned over as needed.

I would recommend an online search of Benches made with Ikea's line of butcherblock countertops.

The time in benchmaking is consumed by the laminating process.

http://www.sawmillcreek.org/showthread.php?81470-IKEA-countertop-for-bench-top

Steve Voigt
05-17-2015, 7:55 PM
I suggest you build a split-top Roubo, scaled to the dimensions you want. A single top of the size you are talking about would weigh about 375 lbs, presenting all sorts of logistical problems for building and installing the thing. A split top would be easier to install, and easier to flatten later on.

ken hatch
05-18-2015, 9:22 AM
I suggest you build a split-top Roubo, scaled to the dimensions you want. A single top of the size you are talking about would weigh about 375 lbs, presenting all sorts of logistical problems for building and installing the thing. A split top would be easier to install, and easier to flatten later on.

I'm with Steve....In fact he beat me to the suggestion. I would just add one thing, 400mm (about16") or even 375mm is plenty of work space and has two big advantages. Each smaller slab is easier to handle and each can be run through a typical small shop planer. The split and its fill would do a couple of other thing for you, the split fill would define each work space and allow limited tool storage while working.


The working side of my split top bench is just over 400mm, here is a photo of it in use with a tool stored in the split:

http://i257.photobucket.com/albums/hh222/VTXAZ/bathVanityTopJointing20150509_zpsoi86dgtt.jpg

ken

Steve Voigt
05-18-2015, 10:38 AM
I'm with Steve....In fact he beat me to the suggestion. I would just add one thing, 400mm (about16") or even 375mm is plenty of work space.



I guess we are on the same page today, Ken. :) I agree about the size of the bench. Just because the old bench is 42" doesn't mean the new one has to be…something more like 36" would be plenty big enough, and would allow a little extra floor space.

Susan Lamb
05-19-2015, 7:10 PM
A hearty thank you to everyone who gave our wide roubo problem some consideration. The ideas that came forward are truly helpful. I now prefer one of the ideas presented here, but will wait for the group decision. If not too much time passes before then, (after all, we are a committee and we are seniors) I'll post the result here.

Susan Lamb
01-08-2017, 8:45 PM
351194 Special thanks to Steve and Ken for getting us started on our split top roubo. We completed it in the summer of 2016 and it is working beautifully. There are 103 seniors in our group (Vancouver, Canada) and we regularly have five at the bench at once. We now have holdfasts, a leg vise, a wilton vise (added after the photo), a couple of battens, bench dogs etc. etc. and can hold our work every which way from Sunday. Hooray!

Andrew Nemeth
01-08-2017, 9:25 PM
Looks like a fantastic bench. You should all be proud!

Phil Mueller
01-08-2017, 10:26 PM
Very well done, Susan (and committee!). I'm sure you will all enjoy it for a very long time.

David Eisenhauer
01-08-2017, 11:56 PM
Great bench, great problem fixing. If possible, please stay in touch and send in photos of the various works-in-progress. Seeing fellow seniors at the bench makes me smile.

ken hatch
01-09-2017, 2:58 AM
351194 Special thanks to Steve and Ken for getting us started on our split top roubo. We completed it in the summer of 2016 and it is working beautifully. There are 103 seniors in our group (Vancouver, Canada) and we regularly have five at the bench at once. We now have holdfasts, a leg vise, a wilton vise (added after the photo), a couple of battens, bench dogs etc. etc. and can hold our work every which way from Sunday. Hooray!

Susan,

Thanks.

The bench looks great. Good on your group. Like others, I would love to see it in use.

ken

William Fretwell
01-11-2017, 10:50 PM
If that bench doesn't generate some inspiration I don't know what will! I hope you have a group photo of the builders around the bench hanging on the wall to remind people where it came from.

Jim Koepke
01-12-2017, 1:28 AM
A wonderful bench and story.

jtk

Derek Cohen
01-12-2017, 1:37 AM
Well done, Susan.

I'm coming in very late, but would have suggested exactly what Steve and Ken did - a double benchtop built onto a single base. That saves bout labour and space.

As suggested, a group photo would be an inspiration to all, and perhaps a plate remembering those that helped with the build.

Regards from Perth

Derek

Chris Hachet
01-12-2017, 8:36 AM
Fantastic bench, glad it is seeing good use!