Intro: 3-Position Grinder Stand
So, who doesn't need a 3-headed grinder stand?
I realized that I was constantly shuffling a pair of bench grinders to the one open spot in my shop, and my nice sharpening station was stashed in a cupboard where it hardly got used. I could buy grinder pedestals, but I didn't want to give up space for 3 of them in my garage.
Instead, I decided to build a single, slightly-larger, grinder stand, and mount all 3 bench grinders on it. The idea is to rotate the stand to access the desired grinder (which is the same one most of the time).
I built this project at TechShop, and it made use of a wide range of heavy-duty tools.
Step 1: Flexible = Cheap
After planning the rough design, the first step is a trip to the industrial metal supplier. I say rough design because you've got to be flexible if you want to be cheap.
I'd decided on material around 3/16" x 8" for the top, about 1/4" x 4" for the legs, and a pipe around 2" x 30" for the vertical column.
I stopped at the counter first and got cut-to-length pricing for my ideal materials. They normally sell in 20-foot lengths, and the cut charge to get a shorter piece was going to kill me. Then I got pricing for their scrap wall, which worked out to be 1/4 the price per pound, compared to the cut-to-length total.
I found a piece of 1/4" x 10" material around 8' long, a piece of 3/8" x 3.5" around 10' long, and a 2.5" pipe around 36" long. This was way more material than I needed for this project, and heavier-duty than I'd planned, but the bottom-line total was the same as if I'd ordered cut-to-length. So, a bit of frugal shopping landed me heavier-duty materials for my stand, plus a ton of surplus material for other projects.
Step 2: Do the Math
I spent a fair bit of time laying out the design and rough measurements to-scale on graph paper. Then I enlisted my high-school son's help for the trigonometry to calculate dimensions of the triangular point on each wedge.
The idea was to take three smaller pieces of steel and join them to form a single 3-wing plate - one platform for each of the grinders. I decided to leave the top hole of the vertical pipe open for a couple reasons - first, to route the power cords through it; and second, so I could weld the plate to the pipe on both the top and bottom.
I cut the plates to rough length, then marked them for the pointed end. I managed to get the first angle cut accurately, so I used it as a template to layout tape marks on the Ironworker so I could more easily / accurately / quickly shear the other 5 angle cuts. That technique worked really well.
Length of the plates was based on how closely I could snug the 3 grinders to each other without them interfering with each other's operation or access. Initially this was worked up on paper, then tested with the real tools. One of the grinders (a sharpening station) had a particularly wide base, so the plate for that grinder would need extra width added later in the process.
To make the center hole, I first drew a circle in Illustrator and printed it on paper. Then, with the 3 plates aligned I used a center punch to transfer the outline of the circle onto the 3 pieces. At this point, I could have used a plasma cutter to cut the arcs, but I opted instead to use a large hole punch as a nibbler to roughly shape the cut. It would later be cleaned up using an angle grinder.
Step 3: Crooked As a Dog's Hind Leg
By coincidence, I designed for 3 legs - not because there were 3 grinders, but because this stand would be mobile. Mobile means the legs can't be leveled in a stationary spot. But 3 legs meant they would always be touching the floor - maybe not perfectly plumb or level, but stable. In contrast, a 4-wheeled base would never be happy, and never be stable.
I decided to try something different with the base - adding a dog-leg, akin to equipment stands in hospitals. The idea was to have enough clearance so the caster could rotate freely, but then drop the base lower where the center column attaches. This would lower the center of gravity, making the stand a bit harder to knock over with heavy equipment on top.
The concept was drafted with a piece of test material to see what angle to make the bends, and how long to cut the legs. I settled on about 45 degrees - the important part being that both bends were exactly the same angle, so the ends of the leg would still be parallel.
Key to making the bends identical was setting an automatic depth stop on the hydraulic press. This causes the bender to only go so far, and yield a consistent angle from one bend to the next.
Similar to the top plates, I printed a template for where the legs meet the center column, transferred the arcs, and roughly shaped ends of the legs using the hole punch.
Step 4: Molten Metal
Then the fun began… weld prep, that is. The most important and least exciting part of welding.
I spent a chunk of time in the sandblasting booth cleaning up all the pieces. There was a lot of mill scale on some pieces, surface rust on others, and the pipe had been painted.
Of course, not all of this prep was needed for welding, but it would be for painting - and I've learned that it's far easier to sandblast pieces before they were assembled into a large project.
Next, all the joints got beveled. I was using a TIG welder that maxes out at 225 Amps, and that wasn't going to cut it for 3/8" steel, so I beveled the joints to get full penetration and ensure they were clean.
First, I joined the plates together to form the top, then ground the welds flush. Next I added side extensions onto one wing to support the wider sharpening station. To combat any possible differences in material thickness, I welded them on the bottom first, with both pieces clamped face-down, flush to the welding table.
Next, I welded the casters to the legs. Normally this isn't a good idea, but I had a specific idea of the finished look I wanted, plus there was a small complication that the caster mounting base was wider than the legs.
Then I welded the legs to the center column. I started with the legs clamped flush to the table, so I could control warping as I applied a lot of heat to the thick joints. Once the top of the leg joints were done, I flipped the project upside down on the floor and clamped it to the welding table for stability while I welded the underside of the leg joints.
Finally, I welded the top onto the column. Alignment took a little finesse, so the legs would be centered with the top. The project was flipped upside down on the welding table so the top could be squared, clamped, and welded on the underside. Then the project was set upright on the floor to finish the top-side weld and grind it smooth.
Step 5: Colorful Cooking
Once assembled, I decided to powder-coat the stand. But, of course, not just powder-coat - I decided that I wanted the center column a different color.
I opted to mask off the center column first, powder-coating the base and the top with a semi-gloss black. On a second pass, I did the reverse and painted the center column yellow. In both cases, the polyurethane wheels were removed from the casters, and the casters themselves were masked off to prevent power-coat from fouling the bearings.
Step 6: Finishing Touches
Finally, the grinders were mounted in position and cabled up. A 13-Amp power strip with an 8' cable was fastened to the bottom of the stand (using machine screws in drilled and tapped holes).
Grinder power cords were tucked down the pipe and out a hole just under the top, and the excess cords were hidden inside the center column. For the moment, the power strip's cord was fished down the pipe and out the bottom of the stand, with about 5 feet of cord remaining, which should be plenty.