The Test Rig
Believe it or not, it’s more difficult than you might think to come up with something that weighs 750 lbs that’ll a) fit on top of the X-Workshop and b) not require you to be too close to it when you load it in case it happens to fall. After some thinking it came to us: water. Lots of water.
To find out exactly how much we’d need, we turned to our trusty Machinery’s Handbook. (We wrote about the latest edition — the 27th — a while back. If you don’t have one of these, ask your family for one for Christmas. It rocks.) On page 422, we discovered that water’s density is equal to 1 kilogram per liter. This is, of course, affected by temperature as warmer water expands ever so slightly such that water weighs less by identical volume as temperature increases. However, the change is only about 0.29% from 39.1 (water’s most dense point) to 77 degrees (about the temp of the coldish water from our outdoor hose). Therefore we didn’t worry about trying to determine or maintain a specific temperature.
So, how much did we need? Google says 1 gallon = 3.7854118 liters and 1 kilogram = 2.20462262 lbs, so:
3.7854118 x 2.20462262 = 8.35 lbs / gallon
750 lbs / 8.35 = 89.8 gallons
That didn’t sound too bad, so we called around a bit and located two 55 gallon epoxy-lined steel barrels — you know, the same kind they ship chemicals in and make BBQ grills out of. After dragging them back to the shop, we used our trusty 125 lb. strain gauge — the same one we used for the AutoWrench tests — to weigh the barrels. Despite their size and durability, they each weighed only 14 lbs. Best yet, they fit perfectly on top of the X-Workhorse.
Adding together the 110 gallons of water plus the 28 lbs. of barrels, we were ready to place up to 946.5 lbs. on the unsuspecting little X-Workhorse. Now comes the fun part — loading ‘er up.
We placed the first barrel on the X-Workhorse, dropped the hose in and turned it on. It took quite a while to fill up the barrel, but we could measure progress easily by feeling the temperature of the side of the barrel. The water was cool while the barrel itself was warmer from sitting out in the sun while we got everything set up, so we just felt for the cool line to see where things stood.
The first barrel’s full and no problems. Looks like the X-Workhorse is good at least up to 473 lbs.
To get the second barrel to sit stably on top of the first we laid a couple of pieces of scrap 1″ square tubing on top. (The tubing weighed 3 lbs. total.) We had to use a step ladder to get the hose into the top barrel. At this point the rig started looking quite intimidating and we were began to wonder how bad the barrels would damage the concrete underneath should the X-Workhorse fail. Failure seemed like a realistic possibility considering that we intended to overload the table by at least 25%.
We decided to stay back as the second barrel began to fill. 900+ lbs. hurts when it falls on you.
After what seemed like forever, we saw water running out the top of the second barrel. Wow! Almost 200 lbs. over the 750 lb. advertised limit and the X-Workhorse is still holding strong.
We couldn’t help but wonder if maybe X-Workhorse relied too heavily on its shape (vs. material strength) to hold this massive weight, so we tried poking at it with a (very long) 2×4 to see if it’d crumple. No luck. Finally we even took a few good (6’+) swings at it. Nope. Solid as can be. It is possible to cause a bit of twisting motion by pushing hard on the X-Workhorse’s legs, but really this would be the equivalent of knocking it over, not causing the table to fail.
So, we gave in and (very carefully) siphoned out the water. Afterwards, the X-Workhorse was still as strong as before and ready for work. It even handled getting wet quite well as the aluminum doesn’t corrode easily and the plastic just wipes dry.
Read on to page 3 for our conclusions.