Saturday, April 13, 2013

ShapeOko : The next step

So I have been running jobs on my ShapeOko cnc mill for a few weeks now.  I think I know where I want to take the upgrades.

These are in no particular order.

Up Sizing

The cutting area I have now is roughly 8x8 inches. A standard plywood Hobby Panel from a hardware depot store is 24"x24 inches. I think I would be using these in various thicknesses for the majority of the projects I will be doing.  The  Maker slide extrusion only comes in 200, 375, 1000 and 1800mm. This translates into 8, 15, 39 and 71 inches.  Not a lot of choices here. The closest size for my use is 1000mm.  When I consider the extra space needed for the machine the overall size is going to be roughly 48x48 inches. About a half sheet of plywood. This is a bit bigger foot print  than I wanted but I can't bring myself to cut down the extrusion. It would just seem like a waste of money.

Mitigate Y Lag

wlanfox great ideal to add blocks to stiffen carriage.
On my machine there is  a very noticeable Y lag that is evident in the oval holes created.  This is happening mainly because of 2 reasons:

  1. Probably the biggest  and clearest shortcoming of the ShapeOko is the unpowered Y rail. I will be going to a 2 motor configuration.
  2. The carriage stiffness needs to be improved. I will be doubling the X rail and using wlanfoxBlocks to stiffen the X carriage assembly.

Another Idea I had was to lower the X rails so the moment arm against them is not so big.  This would be limiting to the Z range but might be worth it.


In a sense I have already upgraded my spindle. I have replaced it with my 15yr old dremel tool. This is because the rotatory tool that came with the machine would not hold the bits in reliably. There is a push button on the rotary tool that is used to stop the chuck from moving while it is being tightened. The button is unable to resist the pressure given when tightening and the chuck skips past the stop for some reason.

The spindle caused milling failures twice by releasing the bit mid-run.  On the second time I cut the cord off and threw it in the trash. I figured I could use the cord on a project and no one should use this tool in this dangerous condition.

I'm thinking that the DW660 would suit my needs. It seems like the bigger brother of the Dremel tool I have now. I will have to research this further but for now, this is my target.

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