I’m looking at getting one of these machines because I need to make RC aircraft molds from MDF board to make carbon fiber/fiberglass parts. I have 2 questions about this I’m using Fusion 360 to design the molds. Sometimes I need to make positive molds. Sometimes, I will need to make negative molds. Can this machine be used for this procress? I notice that the working height of the machine is about 3 inches on the Z axis. Some planes I plan on making are pretty large. Is there any way this can modded (and still work) so that working height on 5ge Z axis can be increased to 4, 5, or even 6 inches? Thanks again in advance.
1. You should be able to use this machine for this application. 2. First, can you locate an endmill that is long enough to cut 6 inches? Will the endmill flex a lot at that length (probably)? This is the longest I have found and it is only 6 inches overall. Extra Extra Long Length End Mills Since you are using MDF to make the molds, and since I have never seen 6 inch thick MDF material, I assume you plan to make your molds in glued up layers. If it were me, I would not increase the z too much so I could keep backlash at a minimum thus increasing accuracy. I would then design my mold, but split it in to layers the thickness of the MDF, mill it in these layers, and design in pin holes to line up the various layers after they are milled.
I'm using Fusion 360 exclusively. If you're going the grbl route, use the Strooom version of the grbl post processor (not the built in one): Strooom/GRBL-Post-Processor Although it says its for grbl .9, I've had no issues with 1.1. I have made some modifications to it to make it a tad bit more user friendly which I'll be submitting to github soon. @Giarc is absolutely right about the issues with increasing the Z too much. Especially on these machines. If you build the machine according to the build video (20x80 on the 20 side), you really only have 1.75" or so. However, you can make modifications to lower the spoil board. That's what I did. Others have lowered it too: Some Improvements on the Workbee 1000x1000 WorkBee CNC build - My honest opinion, tips and help Here's the clip of the build video where you can see how much Z throat you really have with the spoilboard in the top position.
Thank you very much good sir! 1st, you are quite correct in that I would be gluing sheets of mdf board together to provide the base material that needed to milled to produce the molds. I feel you are most correct in me needing to split the mold into layers. 2nd, now that I would need to split the mold into layers, the fewer, the better. When I was looking into the having a 6 inch z height, that was an overall wish as I am quite flexible about that. But, I do feel that the overall height need to be a little bit higher than stock. That leads this question........., you mentioned that workable height is about 1.75”. What is the max z height I can realistically raise this to without compromising the integrity of machine or accuracy of mold? Could I get at least a 2.5” to 3” cutting depth for my molds? Or more like 2” to 2.5”? I ask because I really need more 1.75”. Should I use one of the smalleR machines. Again, thank you very much in advance!!
I don't know what the effective travel of your z axis is but if it is more than 2" or 2.5" then there is the option of lowering the sacrifice board. It will not affect anything on the stability of the machine itself. This option has been mentioned a few times in the past in this forum. You may want to try to search for it to get the idea of how to go about doing it.
As JustinTime mentioned, I would consider lowering the spoilboard. You could download the sketchup file and open it so you can remove pieces to see what the z height could be changed to with modification. I have never seen, or built, a Workbee so I am unfamiliar with its frame layout.
