Hi Group
I’ve been visiting the cnc zone website for a few months. During that time I’ve been reading many of the threads. There are so many talented people that visit the site I have learned allot here. It’s a certainty that I will have many questions for the members of the site.
So now,for better or worst the construction begins. I visited my favorite junk yard. I managed to find aluminum extrusions, Thomson block assemblies and the best find... A 36 X 80 I-beam base. eBay as usual seems to be place to find the expensive components. I found lead screw assemblies with the bearing blocks and purchased two sets. One complete set will be used for the Z axis. The other will be cannibalized for the bearing blocks which will be used on the X axis.
Note: ¾ dia .2 lead In addition, I procured four thk linear sets with 4 bearing blocks. I plan to butt these end to end for the Y axis. For the bearing assemblies I turned two blocks on my old south-bend lathe.
I’ve been working on the electronics for the project. I have one gecko 201 and an Automation Direct stepper. Since I am not an electronics expert to get started I purchased their 40 volt power supply. I haven’t had much success with the electronics part of this project. I did manage to get the stepper up and running. The problem is the motors spins at about 2 to 3 rps. I’ve played with the mach 2 tuning selection to no avail. Hope someone here can help me with this frustrating problem.
So frustrated with the electronics, I started to mount my Thomson 1.25 dia linear motion rails to the bottom of my frame. This required 48 bolt holes to be drilled in the aluminum frame. I got one rail mounted and then setup a measuring system to check the other x rail for parallel. I mounted a dial-indicator attached to an extrusion and linked it to two Thomson bearing blocks. I adjusted the blocks as tight as possible to eliminate any clearances. After about 5 hours I managed to get the two x rails within .001. As a test I mounted a 13 x 36 piece of MDF to the four bearing blocks .. clamped four wood clamps to secure the MDF and pushed the new assembly to test for any binding. It seemed OK but I did push on one side and the MDF did twist a bit. I hope that the machine will not see any offset loads because it did move .010.
In a few days I’ll receive another eBay purchase …more extrusions so I can finish the base. I do have the gantry ends roughed out. I think I`ll send them out to a machinist to square them up. I thought it might be a good idea to have the ends machined so I would have reliable references to mount the other components. Its getting late. I hope you`ll visit this thread again. I`m certain I`ll have endless questions.
Best Wishes, Barry