Bench questions

[Derek Cohen]

I am about to build a new bench. My existing bench is 18 years old, has been modified many times over the years to keep pace with my changing approach to woodwork, and is showing its years. It is small - about 4'10" long. It is too wide - about 26". The top has been planed down so many times that the dowels I used to orientate the boards all those years ago are now showing half their thickness. Although the legs are spindly, the bench is really rigid as it is bolted to the wall (the new bench will be placed about 2 ft from the wall). The Record 52 1/2 vises are now hopeless. The front vise racks and the tail vise does not open unless you hold down the release lever while you turn the handle. And it is too dark. The Karri top may look exotic in pictures, but it does not reflect light well.





The bench has been a good friend but I still find it amazing that I managed to do so much work on it. I procrastinated and avoided building another as I generally dislike building shop furniture. Or using good wood that would better be used on furniture for the home. But now it is time for a new bench, a better bench.


I like the simplicity of a Roubo. I thank Chris Schwarz for his research and the information he disseminated. It has been educational.


Since building a Moxon vise (for dovetailing) a year ago I have come to recognise that my face vise needs (for planing edges) would now be best met by a leg vise. I plan to build one with a wooden screw (a most kind gift of Wilbur Pan), while the tail vise is a Benchcrafted wagon vise.


Generally I try and build as much as I can from recycled timber. I find a lot of old Jarrah roof trusses. These are dry and hard. They will be turned into the base.


Today I dug out the rafters that I thought would work best. These are 3"- 3 1/2" x 4"- 4 1/2" and around 80" long. I should be able to get four legs at 3" x 5". I am aiming for a 34" high bench.





Question 1: Your opinion of these dimensions for the legs? What are the dimensions of your benches legs?


The top is to be 4" thick, 21-22" wide and 6 ft long, built from European Oak (which means it likely originated from Eastern Europe). One of the members of my local ww club bought a shipment imported by a failed business, and was selling it at a cheaper price than the local Tasmanian Oak, which lacks its stability and texture. This was jointed and thicknessed for me, and has been "acclimatizing" (aka lying around) for several months. There has been minimal movement.








Two boxes at the top ... BenchCrafted tail vise and woodscrew ...





Question 2: I plan to add rectangular dogholes. How far apart (my thoughts run to about 3"), and how close to the edge of the bench would you recommend (3"?)?


Question 3: For those using the BC end vise, what is the length of the cut out for the vise? How far along the vise do the dog holes start?


My intention is to build a wooden replica of the steel screw leg vise designed by BenchCrafted. The key feature here are the wheel guides.


Question 4: I believe Chris Schwarz has recommended that the screw for the leg vise is 12" below the top of the bench. Jameel Abraham I believe recommends 9" (but uses a steel screw). What would you recommend?


Regards from Perth


Derek

[Chris Griggs]

Question 1: Your opinion of these dimensions for the legs? What are the dimensions of your benches legs?

I believe mine are something like 5" wide and 3" deep (maybe 5.5x3.5). I too used recycled lumber so the dimensions were simply a function of the size of the beams I used after I finished flattening and squaring them. While I believe bigger may be better, in practice/function I do think 5x3 you'll end up with should work fine.

Question 2: I plan to add rectangular dogholes. How far apart (my thoughts run to about 3"), and how close to the edge of the bench would you recommend (3"?)?

3" apart sounds good, but put them as close to the edge as possible. (Maybe 1.5" centers if you can????)

Question 4: I believe Chris Schwarz has recommended that the screw for the leg vise is 12" below the top of the bench. Jameel Abraham I believe recommends 9" (but uses a steel screw). What would you recommend?

I'd recommend the higher. The less you need to bend over the better - 9" is still plenty deep for most edge clamping.

[Jim Foster]

My legs are about 6"x6"

I made a dog-hole glue-up for my Roubo but did not use it in the final glue-up of the top. Curious if I'll miss it in the end. My dog-holes were 3" apart

My leg vise screw is 9" from the top (See note)

Note: Bench height; 34" sounds high to me unless your tall (See disclaimer) I am 5'10" tall and my arms run a little long. My bench is 31" high and it still seems a little tall. I think the 12" and 9" differences in the distance from bench top to vise screw may be different due to different bench top heights, for a 34" bench, the distance from the top to the screw would have been 12"

Disclaimer: I freely disclose the fact that most of the guys on this forum are far more experienced than I am, so my opinions may be a little on the novice side.

[Matt Radtke]

Those dimensions sound great. I'd try to get the dogs closer to the front and probably a little closer together. I'll measure mine tonight.

[David Posey]

3x5 sounds like a great dimension on the legs, especially if you plan on using holdfasts in them. My legs were 4.5" thick, and I had to remove material from the back side to get the holdfasts to work.

I can't speak with much experience on the dog holes as I don't have a tail vise, but my inclination is to go with Chris in putting them closer to the edge.

My leg vise is 1' from the top of the bench, and I don't feel like it's too low. I usually rest one hand on the bench and turn the screw with the other hand, so it's not a strain on my back. I have a feeling I would do this even if it were three inches higher, and I appreciate the extra room at times.

A 34" bench heigth would be too high for me, but it depends on how tall you are and probably also how long your arms are. The recomendations I've heard for bench height from Chris Schwarz and Roy Underhill are that it either go by where the first joint of your little finger is when your hand and arm are relaxed, or where your knuckles are with your arm relaxed (don't remember which suggestion belongs to which person). I built mine to the taller dimension and trimmed the legs as needed.

Can't wait to see what you come up with. I'm sure it will be beautiful and well documented.

[Andrae Covington]

...Disclaimer: I freely disclose the fact that most of the guys on this forum are far more experienced than I am, so my opinions may be a little on the novice side.

Yeah I don't think I'm really qualified to answer any of Derek's questions, but...

...Today I dug out the rafters that I thought would work best. These are 3"- 3 1/2" x 4"- 4 1/2" and around 80" long. I should be able to get four legs at 3" x 5". I am aiming for a 34" high bench.

Question 1: Your opinion of these dimensions for the legs? What are the dimensions of your benches legs?

My glued-up legs ended up slightly over 5" x 5-1/2". I've never worked with Jarrah but as both a hardwood and a construction timber I imagine there would be no structural problems with 3" x 5". However, I would point out that a larger leg allows more room for mortises for the stretchers. You may have to push the front-to-back stretchers to a higher elevation relative to the side-to-side stretchers.

...Question 4: I believe Chris Schwarz has recommended that the screw for the leg vise is 12" below the top of the bench. Jameel Abraham I believe recommends 9" (but uses a steel screw). What would you recommend?

The top of my wooden leg vise screws are 9" from the top. Occasionally I wish for more depth, but Chris makes a good point that the lower the vise screw is, the more you have to stoop to reach it. Unless you keep stopping and sliding the tommy bar back and forth through the hole in the vise screw head, you really end up bending even lower than you might think as your arm pushes the tommy bar around in a circle. One of the nice features of the Benchcrafted vises is that the diameter of the wheel is much smaller than the diameter of rotation of the tommy bar on a wooden vise screw. On the other hand, two threads per inch goes pretty fast.

[bob blakeborough]

I am going to watch this thread intently...

I to am pondering over the height to build my bench. I am lucky as my lovely wife has given me the spare room in the basement to build a winter workshop, so I am going to build a smaller "practice" bench out of some cheaper pine for inside the house before I tackle my full size Ash bench in the shop next summer, so I am going to be able to test the height first. I am 6-1 but only have a 31 inseam, so my body is a bit lower to the ground but arms are not overly long, so I am thinking I might start out at 34-36 inches and cut off from there if it feel like it should be shorter...

If you don't mind me asking Derek, what are "your" dimensions? Haha! Height etc...How tall is your original bench and how did you find it for planing etc?

[Jim Foster]

Closer may be better, but when you lay them out and cut them, 3" seems pretty close, because the back of one is less than 2" to the front of the next.

Those dimensions sound great. I'd try to get the dogs closer to the front and probably a little closer together. I'll measure mine tonight.

[Sean Richards]

A 34" bench heigth would be too high for me, but it depends on how tall you are and probably also how long your arms are. The recomendations I've heard for bench height from Chris Schwarz and Roy Underhill are that it either go by where the first joint of your little finger is when your hand and arm are relaxed, or where your knuckles are with your arm relaxed (don't remember which suggestion belongs to which person). I built mine to the taller dimension and trimmed the legs as needed.

I have spent 20+ years working (hand tools) on a bench way too high by those recommendations. My current bench is 16 or so years old and has been modified to suit me better 3-4 times - one thing I have never felt inclined to do is shorten the legs. Just another point of view.

[Bill Gulletson]

Never thought I'd be giving Derek my two bits, or whatever the OZ equivalent is!
22 inches wide is a good width for me but why only 6 feet long? You've got the whole outback down there.

[Michael Peet]

Far be it from me to give advice to you, Derek, but I can actually help answer some of these as I have built a bench similar to the one you are contemplating.

Question 1: Your opinion of these dimensions for the legs? What are the dimensions of your benches legs?

I have no opinion on your stated leg dimensions (except for one point below). Mine are nominally 5" x 5".

Question 2: I plan to add rectangular dogholes. How far apart (my thoughts run to about 3"), and how close to the edge of the bench would you recommend (3"?)?

Mine are just under 4" apart, and 2" in from the front edge. Since mine are close to the edge they are bounded by the legs on either end; I spaced them to get a hole as close as I dared to each leg while keeping the spacing consistent between all the holes. One thing I do not like about my setup is that there is a ~6" space between the first dog and the wagon vise dog (because of the leg). Since you are considering legs only 3" thick, you can put your holes 3" in and not be bounded by the legs. I think that benefit might outweigh any negatives related to having the dogs an extra inch in.

Question 3: For those using the BC end vise, what is the length of the cut out for the vise? How far along the vise do the dog holes start?

It depends on the dimensions of your endcap; my endcap is just under 3" deep and the cutout is around 17" long. Note that the cutout under the screw only needs to be as long as the screw minus the endcap: somewhere around 13" or 14" in my case.

My intention is to build a wooden replica of the steel screw leg vise designed by BenchCrafted. The key feature here are the wheel guides.

People think the rollers are all there is to it, but the BC design also relies on a bushing with very tight tolerances around the screw in the front side of the leg. The combination of the rollers and the bushing is what allows the smooth movement. Not to dampen your spirits, but just something to note in case you weren't aware.

Question 4: I believe Chris Schwarz has recommended that the screw for the leg vise is 12" below the top of the bench. Jameel Abraham I believe recommends 9" (but uses a steel screw). What would you recommend?

The tradeoff is capacity vs. grip strength (and to a lesser degree, ease-of-access as noted up thread). All other things being equal, the closer to the top you place the screw, the tighter it will grip but obviously you will lose vertical capacity. I can tell you this: I put mine the recommended 9" down from the top and also lined the jaws with suede as mentioned in the BC instructions. The grip is out of this world, and I do not even have to crank it down very hard. If I were doing it again I might go at least an inch lower, although truth be told I have not run into a capacity limitation yet (but then again I've been using it less than a year also and the wagon vise sees more action than the leg vise).

Edited to add this: one key difference between the Schwarz and BC plans are the placement of the parallel guide: Schwarz's is below the stretchers while the BC design requires it to be above the stretcher to leave room for the roller guides. Therefore, even though the Schwarz plan specifies a screw location 3" lower than the BC plan, the parallel guide is also lower so the ratios are actually closer. After all, it is primarily this ratio of the distances between the parallel guide and screw and the screw and the top that ultimately dictate the mechanical force obtainable by this kind of vise.

In case you haven't seen it, I documented the build here: http://www.sawmillcreek.org/showthre...My-Roubo-Build

Best of luck; I look forward to seeing what you come up with! I used jarrah once on a small project and it was some hard, hard stuff.

Mike

[Salem Ganzhorn]

Derek,
I built my first bench this year. I used BenchCrafted hardware as well. If you haven't already: read and re-read their installation instructions.

When I first started it seemed like the possibilities were endless. After puzzling over it for quite some time I came to realize once you pick the hardware there really are not many more decisions to make.

DSC_4167.sized.jpg

I did a full write up of my build at ncwoodworker do net. The whole process including the thought and mistakes that went into it . Search for "eyekode benchcrafted". The thread title is "Started my workbench!".

My legs are 4x5 3/4". They could be smaller and the bench still wouldn't rack. It is just the lumber I had.

My bench has rectangular dogs. I love them. They work great: easy to adjust, grip great (I use swede on the faces), never twist etc etc. I ended up using Jameel's plan for the dogs: Jameel's diagram.

Mine are spaced 3 1/2" between the dogs. There are a couple critical dimensions:
- The minimum clamping distance is the distance between the dog on the moving vice and the first dog hole. After you do the math you will probably find like me it means the first dog must be embedded in the leg. Not fun to excavate but worth it.
- The distance to the second dog hole is just as critical in my opinion as I use it LOTS. This limits the width of the leg unless you want to excavate it too.
- The distance between your legs factors in as well as you don't want to have to excavate another leg!
- The distance from the front edge of the bench. If you want a sliding deadman (and I do recommend it) your holes will be a maximum of ~1 1/2" from the front of the bench. Otherwise you either weaken the deadman or the deadman would interfere with the dog holes. I think this distance works quite well but I don't have molding planes.

Here is a picture to illustrate the layout of my leg, vice, and dog holes:

IMG_0661.jpg

As for your question #3 it matters how deep you make your end cap and how big you make the moving dog block. My end cap is ~3" thick and the cut out is 16 3/4" long. But measure your own hardware!!!

For Question #4 I only have 7 1/2" from the top of the screw to the top of my bench. The way I got here is by trying to put ~1/3 of the distance between the top of the bench and the screw and 2/3 of the distance between the screw and the lower guide. I was concerned about this but really it works great.

One thing you didn't mention is how you will construct the top. I heartily recommend the split top. My top comprises of two ~3 1/8 x 11 x 80" inch laminated oak slabs. There is no way I could have safely handled two of these at a time! I am sooo glad I did the split top.

Good luck on your quest! I know you will take pictures
Salem

[Bob Jones]

My roubo legs are about 5 by 6. Anything 3in sq or bigger should be fine. I would suggest 3/4 in round dog holes and having then 5 or 6 in off the front. I did that and I use holdfasts in those holes all the time - especially for holding my Moxon twin screw vice. Good luck!

[David Posey]

Derek, this is a bit off topic, but while you're thinking about legs on a Roubo you might want to consider this. I remember reading in Roy Underhill's Woodwright's Workbook about him talking about legs that only go 3/4 of the way through the top. I looked it up and he notes that Bergeron and Roubo both considered this more sophistocated, and that the Dominy workbench was done this way.

If I made my bench over again, I'd try it this way, probably with the same rectangular and sliding dovetail tenons, just not all the way through the top. If I was concerned about the tightness of the fit, I'd either drawbore them to the top or use a foxtail tenon. Just a thought. I doubt it would have any impact on the stability of the bench, but I find it a bit more aesthetically pleasing, even if it does mean the joinery is harder to cut. You would have the advantage of having a top that's a bit easier to flatten since you wouldn't be planing across endgrain, so it is a bit of a tradeoff.

[Terry Beadle]

+1 watching this thread closely !

Yahoo! Go for it Derek!