Chapter 2 - Stand Assembly
The stand recommended in the book is the "Rousseau Workbench System" and is of modular design. Instead of using this system I bought 2" x 2" x 1/8" steel angle iron to make a stand. The important thing to take from the stand is the height of the legs and the length and width of the top. The legs were cut to 32" in length. The top of the table and what will be the bottom shelf are 44" long cut on a 45 degree angle.
I am fortunate to have a friend that would weld the project up for me. I have a small wire fed welder, but like I have talked about before, I don't brag about my messy spatter I make with it. John, on the other hand, is an excellent welder and was kind enough to volunteer his time to help me. Thank you Pastor John!!!
Cutting out the parts.
I cut the parts outline above with a chop saw. There are a total of 16 pieces that make up the basic table. (4) Legs each measuring 32 inches long. (8) shelf pieces that make the top and lower shelf. These are 44 inches long and the inside is mitered to 45 degrees. And lastly, (4) corner foot supports. These are 2 inch x 2 inch right triangles that will be welded to the bottom of the leg for the adjustable feet. I didn't photograph these pieces, but you will see them in another picture after they are welded on. You can click the images to the left for a larger sized image.
Welding up the Table Top and Shelf.
The fist thing we done was to weld up the table top and the table shelf. These were laid on John's steel table to assure that the top face of the frame would be flush all around. One the pieces were squared up together they were tack welded. Each piece was added using the same process. Once all four pieces were tacked together a measurement across the diagonal of the frame was made to make sure that it was in fact square. Then more tacks were made on the edge of the corners, then rechecked for squareness. Once we were happy with it it was welded on both the face and corner joints. We done this for both the table top and table shelf. The welds were ground to leave a flat clean finish. The pictures to the left show the completed parts.
Attaching the Legs and Bottom Shelf.
With the top and shelf welded up, it was time to attach the legs. Squaring the legs was a bit of a challenge to sort out. Our first try was to set the table top on its face and place the leg to it. The problem was that once to tacked one side you could not move the leg at all to make it square to both edges of the frame top. The solution was to lay the frame top on the leg, square it up on one plane, tack it and then square it up on the other plane. Once both tacks were in place, it was double checked for squareness. Once we were happy with it, it was welded up. We repeated this process for each of the legs. Once the legs were welded to the table top, the assembly was laid in the floor and the bottom shelf slid into place. Just as a note. The top of the legs are flush with the top of the table. The Top of the shelf is 25" below the bottom of the table top frame. Once the bottom shelf was in place and tacked at all four legs and we were happy with it, all the joints were welded.
Attaching the adjustable feet and bottom plates.
With the table all welded up, all that was left to do was to make a means of adjusting the table so that it can be made to stand on a level plane. John's idea for adjustable feet was to weld 1/2" bolts to a large heavy fender washer. To the fender washer would be glued some heavy rubber pads made from some shocks he had laying about. A nut is run all the way down the bolt and a washer placed on it. This bolt would go through a hole on a plate welded to the bottom of the leg and finally another nut run down the bolt. In use, the bottom nut on the leg can be turned to jack the table up or down and the top nut locking it in is final position. It was a good idea and saved me from having to buy some. The plates that are welded on the bottom of the legs are made from triangular pieces that were left over from cutting the parts out. They are roughly 2" x 2" x 1/8" right triangles with a 1/2" hole drilled through them. These are welded to the bottom of the legs on both sides of the plate. These little pieces are expected to carry the entire load of the machine, table, computer, etc. The pictures to the left will give a better view of the parts. The rubber feet will be glued on with epoxy after they are cleaned up and painted.
All the welding finished.
Here is a picture of the Krmx01 CNC stand after all the welding has been completed. Now it isn't finished yet. I still have welds to grind down, dirt and grease to strip off and painting to do. I also need to epoxy the rubber pads to the feet after they are all cleaned up and made pretty. But we had spent a little over 5 hours getting to this point, it is sleeting outside and I need to get home. I will post more as I get it done.
Painting the stand.
Well, quite a bit of time has passed since I worked on this project. Kids, work and other things tend to get in my way sometimes. Well my son Mike and I had some time to spare today so we decided it was high time to get the stand painted. We started with using an air sander and wire wheel to knock off any loose grime and rust. We also took the grinder to the welds to smooth some of them up a bit. John really is a pretty good welder so there wasn't much to take off or clean up. Afterwards, we gave the frame a good cleaning with some mineral spirits and wiped it down. These three photos show that we started with the sand upside down and painting the bottom and insides. We gave it three coats before turning it over.
These pictures show the stand right side up getting a few coats of paint. I have not sprayed any spray paint from a can in ages. It took a few runs to figure out that I needed to be a little further away from the work and not so heavy with the spray. No worries, we used all three cans that I bought. It still needs more paint. I want a nice even color and a couple more coats should give me what I am looking for. After this cures I will sand the runs and re-coat. Also, we gave the feet about four coats as well. Next we will need to glue the rubber bottoms to the feet with some epoxy or maybe just some silicone. This part of the project is just about done.
Adjusting Feet and Holes for top.
I thought I would post a couple more photos of the stand before finishing up the painting. The first image is of the adjustable feet John and I made. These are just large washers with a 1/2" bolt welded to them. The black rubber bits in front of them were made from shock absorber bushings. We ground the tops off the bushing to make them flat. I will epoxy or silicone these to the bottoms of the washer. This will allow me to make adjustments to the frame to level it out. The next photo shows where I drilled the holes for the MDF that I will use for the table top. Since I didn't use the stand in the book, I just spaced these how I seen fit. The outer holes are spaced 4 inches from the end and then the inner holes are 12 inches apart. This weekend I will finish painting the stand.
The Feet attached to the Stand
Here you see one of the feet attached to the stand. I thought this would be a good view of it before I set the stand upright proper. If you look closely, you may notice that the foot is not entirely level. Well, some of that is the angle of the shot and some of it is that it is not entirely parallel to the stand. When you weld a bolt to something, the welding tends to pull it to the side a bit. I suppose if you are careful, you could get it pretty straight. However, I am not too worried about it. The rubber foot will make plenty of contact with the floor and work just fine.
Starting the top
I have the sheet of 3/4" MDF cut into two pieces measuring 48" x 48". That is one of the nice things about MDF. A sheet actually measures 49" x 97" allowing you to get the full 48" x 48" pieces from it. Here you see the first coat of paint on the material. I intend to get enough coats of paint on this to make it a nice and uniform color. Then I will turn the sheets over and start drilling them for the bolts on the top. When the sheets are drilled and the counter sunk holes are made, I will then finish painting the top and sides. I figured this would be the simplest way to paint it. That way I didn't have to mask anything off to keep it from getting on the red stand. Note that I will not paint between the sheets. With it bolted down and the side thoroughly sealed with paint, I don't think I have a worry with moisture working it way in. I live in the south and high humidity seems to be a fact of life here.
Doing the other side of the top
Here I have started the other side of the top. The top is bolted to the stand with 16 bolts. The first image is the hardware laid out and ready. Once the bottom of the top was second coated and well cured, I flipped the top over and centered it on the table. When I was satisfied with the positioning, I drilled the 16 holes for the bolts. Four of the holes had to be countersunk for the heads of the carriage bolts because they would interfere with later construction. On these, I used a long 1/8" drill bit to pilot the hole all the way through. Next, I used a Forstner bit to cut the counter sinks then finally drilled through with the 1/4" bit. Once all the holes were drilled and the bolts test fitted, I gave the top and edges their first coat of paint. I apologize for the image quality of the painted top. Seems like I have some MDF dust on the lens. I will be sure to clean it well before I take more pictures. When the paint dries I will give it at least another coat. I want to make sure the top is well sealed especially on the edges and that is has a nice uniform color. I am nearing completion of this part of the project. I will have one more section and some discussion about what I plan to do with the rest of the stand and why I have not attached a shelf to the bottom yet. But first I need to finish the top.
The Finished Stand (Well ... sort of)
Here are a few images of the completed stand. I say sort of above because there are more things to do to the stand but these additions are a variance from the actual construction of the machine. I will discuss these below in more detail and show them is a different section of the build when I do them. So back to the images. The stand top has been painted and bolted to the stand. It is kind of hard to tell but there are four bolts that are counter sunk into the top. These are to clear the struts that will go across the table top. As a side note, The image above with the spots... I thought was a dirty camera lens. But after cleaning it and having the same issue, I discovered with a little help of my son Mike, what we are seeing is fine dust particles in the air where we were trying to dust things off to get a better picture. So we let the dust settle and took a couple more. Sure enough, that was the cause of the mysterious spots. Go figure!!!
How I plan to finish the stand
You notice that there has not been a shelf laid in the bottom section of the stand. My goal is to take an old aluminum computer rack and cut it down. Then mount the parts in the stand so I can mount a computer and other hardware in it proper. Once I get that in there to my satisfaction, I will put a shelf on the reminding section of the bottom to hold a small shop vac and perhaps close in the sides. I have not really decided yet. I will cover these additions in a different section of the build log. But as far as chapter one of the book, this is where I end with it. I will be starting the build of the Y-Axis members next.
The feet that we made using the shock bushings didn't work as well as I had hoped. The rubber was a little too soft and would allow you to grab the machine and shake it. Now to be honest, some of the movement was coming from the stand. Hind site is a beautiful thing. Had to do again, I would have made it from 3/16" or 1/4" angle for the weight and rigidity. But there are things to do that will rigid the stand up nicely. Now as far as the feet are concerned, I had two choices. I could have replaced the rubber on the bottom of the feet with some conveyor belt material, OR ... I could use the feet from a Bone Densitometer that I salvaged when one was being replaced at my work place. I opted to use them, it would be quicker. Lastly, I have to say, the machine is quite heavy and lifting one side so the feet could be replaced was hard on the hands. But anyway, the picture shows one of the new feet added to the machine.
See you in the next section ...