That’s a great solution to making the bits the same length.
Soft limits are a good idea. However, when people have been breaking their z-axis it is usually a mistake, and thus it can be anticipated that even with soft limits, a mistake might be made resulting in over-travelling the z-axis. Additionally, since Ground Control does not have the ability to track the position of the z-axis, then there is no way beyond the user to prevent over travel, and as we just established, mistakes are made. Limit switches take that potential error out of the equation with regards to over travel breaking the z-axis. They would not, however, eliminate the possibility of gouging your workpiece
Another benefit of limit switches is that they could be utilized in setting up software limits by allowing the Maslow to determine the total length of travel available. I think that actual implementation of soft limits with regard to absolute travel would be overly complicated for the machine, not, perhaps, in terms of coding, but certainly in over automating the machine. On some level the operator has to take responsibility for the operation of the machine. Even as an entry level CNC platform, I don’t believe we are trying to work toward a CNC for Dummies, but it could be a very nice add on for those so inclined.
Also, I feel a little bad about hijacking this thread. Perhaps we should start a z-axis improvements thread?
Hey @BarryRalphs, so I would take a picture but I am currently out of town. Basically, the tape I put vertically inside the router base at 120 degrees to each other just to provide 3 points or surfaces of contact. I used the anti-rotation slot as the datum for the edge of my first piece of tape.
If you were looking for the data on the bushings I did mention that a little higher up. But they are Hillman brand from Lowe’s 1/2 ID x 5/8 OD x 1/2L.
I’ve salvaged a couple of microswitches from an old PC mouse, and have a ‘PANIC’ button all soldered up to some ribbon wire ready to hot glue onto my Z-axis, but don’t want to be so bold until I know how to hook it up at the Maslow/Arduino end. Any hints greatly appreciated ;¬)
Real E-Stop switches are easy to find, below is one already in a box. Much cheaper on eBay and the big rock candy mountain (i.e. Chinese megastores) but without free Prime shipping they take from a week to a month to arrive in Mooseville. Hmm, if I leave all the stuff on the end of the link will the referral fees fund another Maslow?
Have you done much cutting with the collars on? Which collars are you using? I found some that have a single set screw, but I’d be worried that spinning an unbalanced collar like that would prematurely wear the bearings on the router.
Any experiences you could share would be appreciated.
I am considering cutting some custom rings from HDPE and figuring out a press fit solution, but if there’s an COTS solution that works…
Here is the collar I am using. I have mainly fiddled. Spent much time with calibrations. They are so small I can’t imagine the loads are anything in comparison to the lateral load we are applying at the tip of the bit for a full depth step down.
Hey @arnoldcp thanks again for info and pictures so far! Could you please share a picture of what your Z setup looks like with the locking tab and its plastic spacer installed, and the two drilled out washers epoxied to the top and bottom of shaft?
Many of us would greatly benefit from seeing your modification to the recommended router! My friend is on the fence between same rigid router or a custom spindle and custom Z, but if your mods fix my occasional locking tab letting go, would be very great
So here are a few pictures of the modified peices installed. You can see that fairly clearly in the first picture the washer that sits beneath the threaded shaft. No need for epoxy on that, only on those white plastic spacers.
That’s about what I was seeing. Yours might be ever so slightly worse.
The increased bearing length of the spacers makes a big difference in the twisting right away, then when you add the washer you have then eliminated almost 100% of the up down.
