Assembly - Day 1 Notes

So I got my core box last night, rails and waste board to come hopefully today (haven’t looked at tracking).

Started doing the first few steps of the build today, around 11:30-3:00, with a few smoke breaks, a shower, and a run to the bank to make some deposits. So not a full 3.5 hours…maybe 2-2.5 to get through unboxing, setting up the work area, and getting through the first steps of the X carriage and Y plates.

If my slides and such come later, I’ll probably do a little more tomorrow. But I wanted to get down my thoughts for today, knowing other people are starting their builds too. Sorry this is in no particular order…

  1. Come to the forums for help if you’re stuck. I got answers in minutes to my questions! This is a great community.
  2. You have to pull the ends off the drag chain - this isn’t in the instructions. I looked for 10 minutes thinking I was missing a part.
  3. Take breaks with your hands often. If you’ve ever assembled Ikea stuff with a hex wrench, this is about the same…my hands are killing me today. No way I could tap the rails by hand tonight.
  4. Limit switches SUCK. There has to be a better way. If I have to ever take these off to replace, I’m going to glue them back on. I spent another 15 minutes looking for the tiniest nut I’ve ever seen when it bounced on the floor and under the table.
  5. Sweep before you build. Looking for a super-tiny nut in a pile of dust bunnies isn’t much fun!
  6. Little bowls are great for storing parts…but label the bowls or keep the bag with the label under/in the bowl.
  7. Don’t empty a bag into a bowl unless you need to. For the standard nylock nuts, washers, and screws for the x carriage and y plates it’s fine. But when you have to go find the limit switch kit and only need 1/3 of each bag…keep them in the bag for later, it’ll be 2 hours until you’ll need them again.
  8. For me, the x carriage power plate thing was very very close to being impossible. It goes in slightly diagonally. I saw it in the pictures in the instructions, and on my machine. It didn’t fit perfectly level with the bottom of the carriage.
  9. If you have a small electric screwtool that has a bit small enough for the limit switches - use it. Those are LONG bolts for such a tiny bit, and your fingers with thank you for not using the eyeglass screwdriver in the kit.
  10. Get needlenose pliers to hold that tiny limit switch nut. The only pliers I could find were about 15 times larger than they needed to be for the job and those things are TINY. You WILL drop them.
  11. Y plate motors are a PAIN to mount after your put on the idlers. I thought I read somewhere that you could put the motors on first – but search the forums. It’s very hard to get those nuts on, and you cant hold it with the closed end of the wrench included in the kit.

Ok, enough for today. My “Top 11” tips for your first day of the build process.

It is SO COOL watching this come together in tiny pieces!

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I’m in the same boat for parts on hand - half of mine arrived today, the other half is taking the scenic route.
I started assembling what I could, got to the switches and decided it was time for lunch. Random thoughts going through my mind at this point were:

  1. If you’re going to just use three, don’t call them “limit switches for homing”. Call them homing switches. That won’t confuse anyone who actually knows what a limit switch is.
  2. There is “Walmart cheap” and there is “dollar store cheap.” These switches are “dumpster-diving behind the dollar store cheap.” Yes, I heard the argument about making CNC affordable to the masses, but there are limits (no pun intended) and whoever authorized these little trinkets should be ashamed.
  3. It’s nice wire. For really cheap switches. Did different people do the parts ordering? If so, I hope the guy that ordered the wire doesn’t get in trouble for being too extravagant.

And now it’s time for lunch.

Do note that I said limit switches suck, not THESE limit switches suck. I know nothing about if they are good, cheap, or junk…they’re just a pain to install in general… I just hit “yes” to everything in the configurator and presumed I needed it all.

Then I saw the part about soldering only if you got switches and…well…I’d almost wish I would have skipped that part. I almost decided to not bother putting them on and hoping…but since I didn’t feel like running wire twice…I guess I’ll use them.

But I am not going to screw them in again. The x carriage ones were near impossible to put on, and the holes in my y plate were so tight I had to crank on the screws to get them in…then I put the nuts on the end, had to back the screws almost all the way back out, and then screw them in again with the nuts on them.

Never. Again. If these things break like people have mentioned…then I’ll just glue them on over and over again.

I still don’t know what they do. :wink: I know very little about machines like this.

As far as limit switches go, I would say that these are standard. Maybe a better choice would have been ones with 0.110", or, 1/4" quick-disconnect tabs for push-on, crimp terminals.

For those looking for tips, I would also check this thread out:

I haven’t finished my machine yet, but didn’t find the install of the switches that bad, yes the little nuts are a bitch but hardly the end of the world. As for quality they’re not horrible, from what I read the bigger issue is how the software reacts (or doesn’t to them). At the end of the day as long as they shut the steppers off thats all that matters. Basically there only use in this situation is to stop the gantries from smashing when a bad gcode is produced (one of the most important functions, unless you want to replace your slides constantly).

The worst part so far for me was having to turn over the machine when installing the nuts for the x axis, this 1000x1000 is a big machine! Tomorrow I finish the wiring. Taking it slow, I find building these machines are half the fun, and education.

Actually, they are not set up as limits. They are simply homing switches. :open_mouth:

Yes, they are set up as homing switches, but that’s not how they are sold. And that is why I made the comment “Call them homing switches.”

Limit Switch Kit - [Add $20.00]

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Interesting, what about adding a wire to each corresponding stepper to cut it off when hit, or reverse wires when hit, wouldn’t that work?

Grbl has support for limit switches, but the issue is that out-of-the-box, there’s going to be too much noise on the switches, and it causes too many false positives. I’ve picked up some shielded cable and hope to investigate what all needs to be done to enable the hard limit feature of grbl.

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Sure, but, you would need to break two circuits per motor. The other option, as PeterJames touched on, is to tweak, then, recompile grbl to make them true limit switches.

Well, I don’t know that I said end of the world…but I did find that my Y plate holes were quite tight and there was a lot of playing with my small nuts for that particular switch. I mistakenly screwed it all in THEN grabbed the nuts, only to realize I couldn’t push the screw back through to try and hold the nut flush with the plate, so I had to back them out and start almost from scratch again.

That was my mistake, and one I hope to prevent others from making. Turning that little screwdriver…hurt my weak nerd fingers.

I did this as well. i picked up some 22/2 shielded security wire and will use that once i start to assemble my x-carve.

If you want to implement Limit switches you will need 2 more switches, One for each end of the X and Y axis travel.
The switches are generally wired in series as normal closed so that if either one opens on contact of the axis it signals a shut down.
You then set up for one of the switches on an axis to be a home switch and a limit switch and the other end as a limit switch.
so you have X home, X+ limit and X- limit and Y home, Y+ limit and Y- limit
Z only gets Z home and Z+ limit

As has been pointed out with the use of a brushed DC motor that generates a ton of electric noise you need to use shielded wire for your limit switches and keep those wires as far away from other wiring as possible.

Hope this helps


got my machine 2 weeks ago, finally got spot set up started going thru it and no parts page or assembly instructions. Is there a download for instructions on pdf?

If you go all the way down to the bottom of the home page you’ll find a link for x carve instructions