WZ9V build log

[wz9v]

After a weather delay yesterday I received my kit (number 1473) today. Now I just need to clear off the table I'm going to use for assembly and get started. With any luck my spindle and it's power supply won't be too much longer and I still need my buildlog.net inspired stepper board. I do have some 76oz/in NEMA 17 steppers ready and waiting for their new home.

just got the 400W spindle, mount, controller today also. Don't have the 48V supply for it yet but I can probably test it with the 12V supply I use for my R/C chargers.

[wz9v]

Kit went together smoothly. Unfortunately the only electronics I have so far are the steppers so I'm stuck until them come in. Best I can tell I'm missing one of the 1.25 metal spacers.

[wz9v]

Got everything built up this weekend at least to the level of the parts I had already.
- Mechanical kit
- Steppers NEMA 17 76oz/in
- 400W eBay spindle

Have some 4 conductor shielded wire and aviation connectors on the way for the stepper wiring and still waiting on the 48V power supply to arrive for the spindle. Have an Arduino UNO handy, just need to get my stepper shield and drivers to round out the electronics. Still trying to decide 24V or 12V for the stepper supply.

Oh and yes. I have the very stiff Z-axis problem. I've tried the drill and it works the carriage up and down OK but the rod gets really warm. Trying to turn it by hand it is really stiff. Gotta get that sorted or I'm sure I'll overheat the Z-axis stepper.

Didn't think I could mount my spindle with the stock mount and then I noticed that people were mounting the DW660 with it and my spindle at 52mm diameter was smaller. Just have to check clearance at the top end but looks good so far.

[WillAdams]

Getting a bit concerned about all these Z-nut issues.

Wish we'd gone w/ ejs's design: http://www.shapeoko.com/forum/viewtopic ... 720#p12964

[cvoinescu]

I like Improbable Construct's design better (the Acme screw).

[WillAdams]

So do I, but it's significantly more expensive, and requires that the Acme rod be machined to spec and that one provide a couple of extra washers --- the machining is the real killer, since we seem to already be having supply issues for parts.

I wonder if ejs's design couldn't be cut out of HDPE rather than Delrin since there're no bearing surfaces save for sliding against the MakerSlide.

[WillAdams]

Another possibility is we may have a batch of bad M8 all-thread rod --- anyone who has a too-tight nut should consider spinning by a hardware store and trying the nut on different samples to see if it works better.

[cvoinescu]

That sounds unlikely, both because it's much more likely for a custom part to be slightly wrong than a commodity item, and because, in my experience, it is the nuts that are sometimes too tight. In one batch, I had to run a tap through as many as a quarter of them to make sure they worked nicely (I test every single one); other batches were better, with only a handful too tight.

[wz9v]

The metal nuts that capture the bearing ran up and down the rod with no problem. The Delrin block is what is tight, before installing it i ran it up and down the rod by hand a few times and it was tough but not really bad. Once I assembled it into the z-axis it got worse. My drill can easily force it up and down but it is a royal pain to move it by hand so I'm thinking the stepper will have trouble.

I'd do the ACME screw upgrade if it were in stock. Until then I'm in search of alternative solution. Somebody mentioned an M8 tap would help.

[danimal]

I used this nut in my most recent modification.

http://www.cadcamcadcam.com/acme-nut.aspx

It is simple, relatively cheap, made of delrin and anti backlash. Maybe someone makes this in other thread patterns. Possibly incorporate this design into the standard nut? It seemed like a nice middle of the road solution to brass nuts or other anti backlash solutions. I think that i paid $7 off of ebay for mine. I bet in bulk they would be very reasonable.