This is my second attempt at improving the C-Beam Machine. The first was documented elsewhere on this list. (C-Beam Machine Too) It involved the addition of some Chinese linear rails and a lot of changes based on reusing most of the original components of the CBM kit. That build evolved over time as I was building my own machine to mill aluminum.
This is a concept build, I have not yet built one of these, but I put some thought into how to improve the original design without going overboard. The redesign has several advantages over the original:
1. It uses low cost stock components, and the cost to build should be not too much higher than the original. There are some added components which will increase the cost, but shouldn't be more than 20% or so. I have not costed out this model yet so I am not sure on this.
2. The machineable area is almost doubled over the original design, almost 380x380mm, where the original was 300x280mm.
3. I used C-Beam for the support uprights, which is more compact and stronger than the original
4. I also used C-Beam XL plates for the X and Y axes, which are inherently stronger and use 50% more wheels
5. I added additional support for the table by putting 4 more wheels on the outboard edges of the table. This increases stability and support immensely over the original which was a bit wobbly on the table, especially when cutting near the extremes of X axis travel.
6. I used the double wide C-Beam gantry plate for the Z axis, which is much stronger, doubles the number of wheels, and allows for a double router mount. (see Extra Strong Double Router Mount)
Let's go through the list above in some greater detail.
Going with the C-Beam XL plates gives us 6 wheels instead of 4 on the X and Y axes. These plates are thicker and much stronger than the small Universal Build Plates on the original. It also simplifies mounting of the Z axis, and in the case of the Y axis is stronger than the Universal Build Plate used in the original design. Using the smaller CBXL plate also gives us a large increase in Y axis travel. The spoil board is elevated a bit over the original design so it can fit over top of the Y axis motor, further increasing Y axis travel by almost 100mm as well.
Using C-beams for the uprights has several advantages over the original design:
- They are stronger and more compact
- each upright is a single piece
- They can be joined together top and bottom by 20x40 braces, which increases the overall rigidity
- The X axis beam can be better supported top and bottom
- Since the C-beams are thinner than the original 20x60's, coupled with the different placement of the top corner brackets, the X axis travel is increased by almost 80mm from stock without changing the length of the X axis C-Beam.
The spoil on the original design had a lot of flex vertically on the extremes of travel. It was essentially just supported in the center by the gantry plate, and nothing held it from flexing up and down when the X axis moved across it. I addressed this problem by adding a couple of pieces of 2x2x1/8" aluminum angle under the spoil board on each side. (this 2"x2" angle is available from Home Depot) Drilling these angles for offset spacers allowed adding a couple of wheels to support the edges of the table. This almost completely eliminates up and down movement of the table edges under load.
The wheels run in a couple of 20x20 v-slot tracks fastened to the cross pieces of the base. In the drawing shown, the wheels are about 140mm apart. This keeps the length of the tracks to just a bit longer than the base assembly. If one were to increase the spacing on the wheels, the table would have more stability front to back as well as side to side, but it would necessitate increasing the length of the v-slot tracks so they stick out more past the ends of the base. If you have the room, this is a good option.
The table also benefits from the 2x2" angle making it much stiffer front to back. It is well supported in the center by the gantry plate, making the whole assembly stiff and strong. The MDF spoil board could be easily replaced with a 1/4" aluminum table, which would allow the machine to use mist cooling for cutting aluminum. The aluminum table could also have tapped holes added for hold downs, a vice, or t-slots for work holding.
Finally, the Z axis is beefed up by adding a double wide C-Beam gantry plate for extra strength. This limits the travel somewhat, but this machine has limited space between the X axis and bed anyway. Spacing is still more than sufficient to get more than 3" of Z travel. The double gantry plate also allows the use of 2 standard OB router mounts one above the other, and with the Dewalt or similar routers with the long barrel, adds a lot of strength to the Z axis.
The liberal sprinkling of 5 hole corner brackets to support the base, uprights, and X axis beam also add a lot of strength ot the design. 6 hole corner brackets and cast corner brackets are also used throughout to tie various elements together.
The rear view shows my signature Electronics Panel with Dust Cover that I use to build all my machines.
I have these panels punched by a local panel shop, they are 500mm x 120mm, have hole patterns that fit the power supply, an Arduino Nano screw terminal board (they are not drilled for the Arduino Uno as shown), along with 4 sets of holes for various stepper drivers including the DQ542's. I can sell them for $30 each, and the dust covers are also $30 each.
Yet another build of an improved C-Beam Machine, improving stiffness, size, versatility, and strength without increasing costs much.
- Build License:
- CC - Attribution NonCommercial - CC BY NC
Reason for this BuildTo improve the original design
Inspired byUnknown author who first suggested the wheeled support for the table