I've been working on a workbench for my garage-shop. Since space is at a premium, I decided I wanted it to both be a work surface and a place to hold some of my larger wood working tools.
I started with mock CAD models of the tools: bandsaw (12" Craftsman), table saw (10" Craftsman), drum sander, miter saw (10" Skil compound sliding), and router table (Kobalt). These models have accurate dimensions but not most of the details. I spent some time arranging them in logical fashion. I wanted the miter saw and router table to have long in-feed and out-feeds, which necessitated putting them in the middle of the long edges. Luckily, they both fit in the middle. The band saw doesn't need much in-feed, nor does it need any work surface to the left of it (because of the throat), but a long out-feed would be nice, so that meant sticking it in a left corner facing and end. The drum sander needed to be in a corner to make working around it easier. That left the table saw on the other end, which gives maximum out-feed table length. Unfortunately, it doesn't give the table saw much width to work with, definitely not enough to cut long boards or sheet goods on it, nor room for a longer fence. My plan for that is to create a separate table with adjustable, folding legs that I can place on either side of the work bench to give the table saw more width to work with...more on that later.
After getting the layout down, I went on to create the framing from 2x4's (1.5x3.5's). The bandsaw, miter saw, and drum sander all rotate down, and a work surface is attached to their bases that rotates up. The table saw is very heavy and the surface is mostly flat, so I didn't see the point in trying to move it. The router table is light weight enough to move down a shelf. I designed work surface pieces to fit between the tools. I then added plywood shelves and drawers to many of the empty spaces.
Table saw left, router table middle, bandsaw right
Drum sander left, miter saw middle
Tools stowed
The top surfaces will be 3/4" MDF with an opaque (probably white-ish) top. The rest of the construction is 2x4s and plywood. The base's outer dimensions are 4ft x 8ft, though the table saw hangs out over the end a bit, and it's fence (to be replaced) hangs over the sides. I had almost all of the 2x4s needed from tearing down an old shelving unit in the garage. They are all older, have a lot more rings than you can buy in current 2x4s, and they're noticeably denser. They also aged to different and interesting hues:
top: recent Home Depot pine, middle two: old fir,
bottom: very old unknown wood
I really like the mix of colors, I think it'll make the workbench interesting looking. I needed one more 8ft long 2x4 for the base and shockingly managed to find a straight one at Home Depot. Most of the 2x4s I have are straight, but the more-warped ones will be cut into the shortest pieces. Screwing into the end grain of a board is not a good idea because the screws can loosen over time, so most of the 2x4 (and other) joints will be by pocket hole joinery, specifically using the "HD" #14 screw ones, with wood glue. I tested this joint and it seems to be stiff enough. Ideally, I'd use mortise and tenon, but I don't have a setup for making those yet.
Cutting the base 2x4s with the miter saw
I joined the four outer base 2x4s with pocket hole joints first. The base plywood shelves are recessed into the base frame. There are advantages and disadvantages to doing this over placing a sheet of plywood on top of the base frame. Advantages: slightly more useable height, no need for edge banding to hide the plywood edge, no need to cut out notches for vertical 2x4s, easier to replace if become damaged (easier to remove and only need to remove the one shelf that is damaged). Disadvantages: have to cut up the plywood sheet (lots of cuts), harder to mount and level each shelf. To that last point, I designed these corner blocks to support the base shelves:
I made them close to the height that, if the 2x4 beams are resting on a flat surface, then placing them in the corner as in this picture results in their top surface being recessed down just enough for the plywood to sit level with the top of the 2x4s. I needed 20 of them, so I used an end stop on the miter saw to cut them all. Each one has four holes, so I printed out templates and spent a couple hours marking and drilling holes on the drill press. I used the "HD" pocket hole counterbore drill bit (1/2" counter bore, 1/4" hole) to drill the deep holes (left in above picture), and a normal 1/4" bit to drill the holes on right. The deep holes are offset inward to allow my driver to fit. I found these "Spax construction wafer head #10 2.5" T-star " screws at Home Depot, which are cheaper and thinner than the #14 pocket hole screws, but otherwise pretty similar. I figured I'd use the spax screws anywhere I didn't need the strength of the larger pocket hole screws, like for installing these corner blocks. I used a scrap piece of plywood to help install them at the right height.
Plywood was just resting underneath, didn't
have anywhere else to store it
For the cross members, I installed four corner blocks on them first, sanded the ends flat, clamped them in the frame with pipe clamps at the correct location, then screwed the blocks (deep holes) into the 2x4s it was clamped between. The result is a very strong and stiff base frame.
Next, I used a circular saw (60T blade) to cut the plywood sheet (23/32" nice pine) into the base shelves. I used a harbor freight clamping straight edge to do this, which I previously didn't have much luck with, but I was able to get within about 1/32" of the desired line this time. I guess practice helps. Given the fact that the recessed areas aren't perfectly rectangular, this was more than good enough. Because I hadn't had much success with the straight edge previously, I left some extra on many of the edges, so I ended up using the circular saw to trim the extra off (made ~2x as many cuts as I really needed to).
The base shelves
Flipped the frame over
I flipped the frame over in order to sand the four outer corners flat. I did my best when screwing the 2x4s together to make sure they were even, but the actual dimensions of the 2x4s varied by as much as an 1/8". One was 1 5/8" wide, instead of 1 1/2" wide, some were 3 7/16" tall instead of 3 1/2" tall. Thus, I needed to glue some 1/16" basswood shims in some places and sand down all the corners to make them flat. I used a handheld 3" belt sander to do this
Flat corner
Why am I flattening the bottom corners? For casters! I bought four 4 inch casters for $35 off amazon. Load rating is 1800 lbs, and my CAD model estimates about 1200 lbs (tools and wood are heavy!), so these should work. This was another advantage of using the corner blocks: can use the shelf support blocks to mount the casters.
The casters didn't come with wood screws, but luckily I had some 1/4" lag bolts (no idea from where), so I used those. I marked and drilled pilot holes before using my impact driver with a hex bit to drive them in.
Casters mounted, frame flipped back upright
I also got lucky that the frame ended up sitting flat, so I didn't need to shim the corners for the casters not to rock. The next step was to sand (palm sander + oscillating saw/sander) the tops of the corner blocks such that the shelves sit level with the tops of the 2x4s. About 3/4 of them needed some sanding, but only two needed a lot (~1/16") of material removed, so overall, I think that plan worked out pretty well. Some of the shelves had to be sanded out-of-square in order to fit, and I used the handheld belt sander to do that.
Test fitting a shelf
All shelves fit
The gap in the bottom left is for the top of the band saw to rotate into, and I'll be cutting a ~1" notch in the left 2x4 there. I'll reinforce that notch with a thick steel straight strap I found at Home Depot.
Unfortunately, I underestimated the flexibility of the plywood, and the three long shelves bowed down a little in the middle.
Middle of shelf sitting about 3/16" inch below top of 2x4
The solution was pretty simple: add middle support blocks.
Middle blocks screwed+glued to sides with same recess
as corner blocks
Sits flush now
Before I screwed the shelves down to the corner blocks, I decided I didn't like the fresh white pine coloring. It's just too light. Thus, I decided to stain the plywood shelves and the one new 2x4. I tried a bunch of different stains and settled on "golden pecan". It's still pretty light, but not as "white" as the raw pine. The process for staining was as follows: sand with 220 grit, vacuum dust, wipe with mineral spirits and lint-free cloth, brush on stain conditioner to seal (for soft woods like pine), wipe off excess conditioner, let conditioner dry 30 minutes, brush on stain, wipe off excess stain, let dry.
Stained shelf. Sorry for crappy lighting
They came out nice. Coloring is much closer to that of the old fir 2x4s. I only did the tops of the shelves since the bottoms and sides will never be seen.
Next steps:
- Finish staining pine
- Screw in the shelves
- Mix stain with wood filler and apply wood filler to screw holes and any gaps between shelves and 2x4s
- Sand wood filler, fix any sanded stain spots
- Seal shelves with 3 coats of polyurethane to protect them while building the rest of the workbench
- Start cutting and joining the vertical 2x4s
I'll show more details of the rotation mechanisms, electrical, vacuum ports, drawers, etc as I continue to build it. I've worked with wood before, but I've never done any woodworking projects this complicated, so this'll be an adventure.
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