The first bench built for conduit installation in part 1 was not really fit for purpose and needed to rethink the design. Most designs on the net seemed to be woodworking designs, I wanted a bench that was both sturdy and simple to build but it needed all the typical features of a laboratory bench.
I went with a straight forward frame this was going to be pinned to wall from the back, with no need for back legs. The front legs would hold all the downward weight, which most of the time would be the bench weight itself and few components and instruments. My original thought was that the bench could be pinned to the wall using Rawl bolts, however this turned out to be a bad idea. The wood I used was 3 by 3 inch square, with a MDF top of 2400mm by 600mm with a 18mm thickness. This presented a problem, I couldn’t find Rawl bolts long enough as a section of the wall was single course brick. I did however buy some long screws to fix the frame together at each corner. These came in handy, as I ended up scraping the Rawl bolts idea. The length that fixed to the wall had to pre drilled to allow for marking of the holes in the wall, this meant I had to align the frame level roughly where I wanted it, remove the frame and then drill the holes. Finding things to prop the frame up so I could make level marking wasn’t fun!
To the cut the legs to the perfect length I used a circular wood saw, this was so much easier than my first initial cuts my hand. The overall leg length measured 850mm.
The first frame was the hardest, and I needed to remove a 25mm slot for the conduit to fit on the wall, I could have quite easily chiselled out a 25mm by 25mm slot, however with the circular saw it just meant making a couple more cuts and leaving the necessary gap.
Deciding the correct height of my bench at around 850-900mm, all the legs were cut to a length of 850mm, 180mm coach bolts were used to fix the legs to the bench frame. I tightened the bolts up with a 17mm spanner and tested the bench frame with my own weight, I couldn’t physically move the frame either by tugging back and fourth.
At this stage a temporary table top was created by balancing any bits of board I could find to make working on the other side of the workshop more productive, it made it so much easier when I didn’t have to kneel on the floor. The opposite side went together without a problem and I put the frame together in no time at all, the only struggle was to keep the frame level especially now it had to align across to the other bench.
At numerous times checking with the level to double check the frames aligned with each other, I was happy to join the two benches together with the final bench on the back wall. Which simply consisted of two pieces of 3 by 3 at the back and front, to support the MDF bench top. The back piece was screwed to the wall in much the same way as the rest of the benches.
It was now time to finally put the bench tops on and screw them now. The frame size was designed to allow me to just drop the two longest length straight on, without the need to cut them. The back bench was the only cut I needed to make and it was a perfect cut, although maybe I needed some safety glasses and a dust mask may have help out here, but by this time it so close to finishing.
I am definitely happy with finished result of this bench build, its was worth spending the time to rethink the design. I would recommend this approach for a similar use case, however for wood or metal working you may need extra supports on the back.