Mark Gottschalk's 2'x8' blackToe CNC Machine
Mark Gottschalk has a blackToe CNC Machine, but not any blackToe, his is 8 feet long! He makes these beautiful fish with this machine, so beautiful that he decided to establish a Kickstarter project
in their honor.
So, what is Mark doing these days. A while after the machine was build and in operation, he sent me a link of his Etsy's page. The work he has done is spectacular. Now, THIS is the way I like to see fish on a wall. Stuffing fish is so yesterday! The wood fish is the new black!!
Some of my customers ask if the the CNC machine kits on this site can be lengthened. This is not only possible, but quite easy to implement. Check out Mark Gottschalk's machine. He did an excellent jog on the construction of the table, creating clamping T-tracks, nice shelf and storage, and a length that suited his needs.
This is one of the most impressive builds I have seen. It is apparent that partly the reason for going with the 2'x8' instead of the 4'x8' for Mark was the space that he is afforded for the machine. The blackFoot would have left Mark little space for anything else. for long narrow spaces, the 2'x6' proportion seems to fit nicely. Still, no room for the car, though. In this image, it is clear to see that the area under the machine can be used for storage, and with the 2' dimension, everything is easily reachable. I could see easily all of my hand tools stored in the shelf space that is created at the midpoint of the length of the table.
The table looks very sturdy. The torsion box holding the table surface also provides the strength to span the two cabinets.
Clamping on this 2'x8' CNC machine will be no problem. virtually any size piece can be well clamped at any position using the T-slot tracks. It's also noticeable that the tracks can be continued to the end of the table.
A very important aspect of this table is evident. The top layer of the table is MDF which is sitting on a plywood substrate (part of the torsion box). First, the plywood will be stable because it is part of the torsion box. Second, the MDF provides stability on it's own with it's amazing property to resist warping. third, the MDF is slightly higher than the T-slots. This will allow Mark to face the entire MDF area so the top is dead level and flat with respect to the z-axis cutting level.
Cable management, without the use of cable carriers, can be a pain in the gantry sometimes, but Mark seems to know what he is doing. He implemented a management method that I implemented on my blackFoot 4'x8'. The cable is fastened at the midpoint of the gantry. He put his on the gantry back. I put mine on the gantry top. Both locations will minimize the slack on the cable while still enabling full reach. It's important to keep the cable as short as possible, and this method works well.
So, where should the limit switches be located. There are so many places on these machines that the limit switches can be placed and I am pleased to see where my customers and users of this website put these switches. For the y-axis, some put the switch flat on the face of the y-axis rail support (front of the gantry) and some put it where Mark has it. Take a closer look and you will see a wood screw at the edge of the Z/Y plate so the y-axis position can actually be adjusted where the switch is engaged.
But! The most interesting place Mark put the limit switch is on the x-axis. Take a look at the image. The switch is located behind the gantry side and slides against a tapered board to engage the switch. This allows the machine to gradually depress the lever so that the machine does not overshoot the end and damage the switch.
Mark has also elected to place all of his drivers well away from the machine. The drivers, breakout board and most of the signal wires are located under the computer. This was a wise decision as the signal wires should be as short as possible. Signals are only in the sub 5 volt levels and draw very low currents. Signals can be more susceptible to interference at long runs. Since Mark has placed the computer and electronics at the other end of the room, the motor power lines will live at much greater lengths.
Overall, Mark has done a great job and shows a very simple method to getting the length of machine that he desires. This machine demonstrates that it is possible to easily customize the CNC kits and the wood really engenders creativity with the way to position limit switches to creating the table surface and clamping methods.