Ramblin' Dan's Workshop

The Sanctum of Fine Art and Invention

Low Work Bench

Recently I decided I had to make myself as comfortable as possible while working in my shop. I have Peripheral Neuropathy (PN) and I am most comfortable when I am sitting down to work on things. I am able to walk around the shop and as you can see here, I am still capable of fairly large and complex projects.

I know my mobile ability will continue to decline so I have set my plans and mind to making smaller projects. With the tools and machines I have, I want to be working on precision metalworking project items that are commonly called metalsmithing. It is a bit of a slide from pure machine shop gears and levers and more of forming the metal. Far closer to jewelery work and model making than building an internal combustion engine. (but I will continue that.)

I observed how metalsmiths and jewelers and watchmakers all have a unique working environment. Many have the heavier tools like I already possess. A small CNC milling machine fits right in to most modern workshops, but a lot of their time is spent in a concentrated work area sitting at a combination high and low bench. Typically called a "jeweler's bench" or "watchmakers bench". That is where a lot of the hand work is done.

My progressing PN is going to limit my manual dexterity but there are so many directions I can go. I don't intend to become a skilled jeweler, I just take inspiration from their tools and working environment. I see how that can help me be more comfortable and steady doing any of the kinds of smaller work I might want to consider.

So I have decided I need a "sit-in-a-(office)-chair" working environment that requires a work bench style very similar to what I have described above. All my existing benches are designed for standing, which is actually the correct height for the top part of a jewelers bench. Only my Taig CNC is on a low bench.

What I show here is my own design for a slide out bench designed to become a part of my big tall bench. Only 16 inches deep and 40 inches wide, it installs like a pull out drawer under the top of the bench. The front edge of the higher bench can serve as a mount for installing a GRS bench pin base for their holding system. All hand work is done elevated above the bench at about mid chest height.

With no legs for support, the bench can't hang out too far or it would be like a diving board. Working off a GRS vice for sawing, filing, carving, soldering and everything a system like that can hold, the lower bench does not need to be anything more than a shelf for tools and lighter duty work.

I have designed it thin enough at the front for easy clamping of accessories but a double layer torsion box toward the rear. Then I designed a full depth box (32") to avoid droop at the front when extended. There is a side clamp that will lock the low bench in any position to add more to the rigidity.

So lets see what it looks like.


 

scan173 scan174
This is a rough preliminary brainstorming sketch. This is how I think with a pencil. Most of this is not what I am building I am a little closer to design here. Close to what I built. But it is still a working drawing and I am free to make changes as I see how I can make improvements.
bench-8 bench-9
I have "kitted" the wood. That means I am cutting out all the parts before I start assembling. This is maple faced 19mm (<3/4") 12 ply (counting the face), good one side. A little closer look and you can see the dado cuts I did with the table saw.
bench-10  bench-11
 This is to be the home of the clamping system. I plan to machine an aluminum "puck" to fit this pocket.  A closer look at the clamp pad pocket. Note the 12 ply plywood used in construction. This recess is about 1/2 inch deep.
bench-12  bench-13
 you can see the center hole here. I plan to machine a bracket to span the puck size that will have say a 3/8 threaded hole. I'll thread a bolt with a hand knob into the bracket and the end will press the "puck" against the side of the slide out tray, firmly clamping it from movement.  That's a little splice pad. I am installing the slide surface for the top of the shelf case. The shelf "drawer" top will push against this top strip when the drawer is pulled out. This "frame" bolts up under the  big bench and the low bench slides into the front. There is a side board in there now for a trial fit. It's sticking out on right side.
bench-14  bench-15
 This splice pad will actually be just behind the 2x6 front edge of the big bench. The front of the box will be flush with the front of the bench. This is a high stress point.  Drawer box is moved. I am beginning assembly of the slide out bench section. That wide piece is the bench top surface, upside down at the moment. The dado is for a center brace.
bench-16  bench-19
 A closer look at the underside of the bench top. The top fits into dado's on three sides and there is also a center brace that dado's into the underside.  The top and sides have been assembled. You may have noted that I use Titebond II and a air powered brad nailer. The brads are really clamps until the glue sets up.
bench-20  bench-1
 This is another sheet of plywood on the bottom. I let the top (now on the bottom) extend but with the center brace so it would be easy to clamp bench accessories to the front. I am about to add the slide runners to the sides. They strengthen the sides (like an I beam) and provide a wider sliding bearing surface.  Here we are with a trial fit, right side up. Of course it is clamped to the woodworking bench top here but will be installed under the big bench. Note the built in 1/2 inch lip around the top to prevent small parts from wandering off three of the sides.
bench-2  bench-3
 Another view of the "drawer" half slid out. This is as far as it is intended to be extended. The back edge of the "drawer" is that cross piece visible in the open space behind the top. That provides the lever to keep the slide out from drooping.  This is a little attention to detail like rounding the edges so there are no sharp corners to poke me in the leg. Here you can see there is a little pocket space for storing something. I have no idea what at this point.
bench-4  bench-5
 This is between the left edge and the center support. Almost all joints are dado or lapped for extra strength.  Back end view. Note how the sides of the "drawer" box are designed as a "C" section. This provides runners for the sliding section and also creates great strength for the side construction. That back edge will exert up force against the back rail of the big bench. The corners are notched so the  top slides are recessed flush.
bench-6 DSC02775 
 A closer look at how the top and bottom are staggered and a view of the center brace. The box is what I call a semi torsion box to stiffen the design but keep the front thin.  Wow! We have some color now. In front of the bench is the frame that mounts to the bottom of my large bench. The  "drawer" bench is upside down on the bench. The blue tape is to keep the finish off the sliding parts. Like a shash window, I don't want to "glue" the bench closed.
DSC02780 DSC02779
The "drawer" bench part is correct side up this time. This received a lot of finish sanding but not too much. This Lowes brand plywood has an extremely thin ply finish surface. Not much sanding needed except to get the running edge to properly slide in the under bench frame. What I am using is dark shellac, about 1/2 this can. I am putting a rather heavy coat on everything except the work surface. I am planning polyurethane for there as a final finish. Shellac will soften and dissolve in alcohol so the top needs better protection for a working surface.
DSC02784 DSC02798 
I did a wipe on the top with an alcohol soaked rag as I don't want a heavy coat of shellac here. The humidity is high this weekend so the polyurethane will have to wait. I did coat half the top part of the slide rails as they are visiable when the bench is pulled out. I like the color.  Time to make the clamp puck. I suppose it could be a wood disk but I have a machine shop and lots of aluminum. I am sawing about a half inch off this bar.
DSC02785 DSC02787
I have already made one pass to square off the face. If you look close you can see there is another pass required. I love these close up shots of the machine work. <g> This is the same side of the puck and without unclamping I am cutting a 45 degree bevel on the edge. Dimensions are not critical so I just eyball these cuts.
DSC02789 DSC02793
I have turned the puck around and I am using A cutting tool to make the back (machined) side square to the face of the chuck. I did the same thing on the first  side picking the squarest looking side first. Side two faced and bevelled the same as the first side. Machining is done at this point. Yes, the cutting tool spacer is removed before machining. <g>
DSC02795 DSC02797
I cut the recess with a hole saw and the guide bit of the hole saw made the center hole. I am going to machine a bracket that is threaded for a hand screw I will mount on the other side. Turn in the hand screw and the puck will clamp against the side of the workbench drawer, holding it from moving in, out, or even side to side. It needs to be a loose fit so it doesn't jam in the hole. I am thinking of a recess pocket in the puck at the rear (for the screw) to aid centering.
DSC02972 DSC02974
This is the hand knob I purchased from McMaster-Carr That bright orange mesh is a thread protector for the 3/8x16-1" stud. The knob is a good size for the intended task. I needed to make a bracket for the knob to screw into. Oh Boy! More machine work. That's a slab of 3/8 x 4 6061 T6 aluminum. I whacked off a little over 0.750 inches.
DSC02975 DSC02977
I am milling the sides getting rid of the saw marks and squaring up the bracket Nothing critical here about measurement. I do want the piece to be square and look at least halfway decent. I learned a long time ago to make critical cuts only when I have to.
DSC02979 DSC02980
That doesn't mean not being accurate. Drilling these holes will be a job for the drill press not the X3 mill. I am tapping the center hole for the 3/8-16 threaded stud on the knob. Plenty of "meat" and strength in this bar for the task required.
DSC02985 DSC02989
I tapered the holes for the screw heads so they would be flush. Nice looking job even if I do say so for myself. I milled a little recess in the back of the "puck" for the stud end. I ground the end of the stud smooth too so the fit would be umm... comfortable.
DSC02991 DSC02994
Thank goodness for the clamps. I couldn't work without these. Once the case is in position it will just be screwing it to the bottom edge of the bench Another peek at the clamping puck on the right side of the case. I suppose lefties could put it on the other side. <G>
DSC02998 DSC02999
At last, the work bench is in place. Just like I thought it would work. It's so nice when a plan comes together. There is my clamping knob. Close enough to be reachable and far enough back so that it is out of the way. No I didn't measure exactly how far back.
DSC03002 DSC03003
A view from the other side with it out. It is very sturdy even without legs on the corners. The cantilever is a good design. This is the "stored" position. I made a video at the top of this article to show how it moves in and out. Very easily.

 I think I got the color match pretty close with the orange shellac. The large bench was coated with boiled linseed years ago and has aged to that nice amber color.

 

Copyright © TEDatum Publishing 2017. All Rights Reserved.