Crusarius Home built CNC

21incher · May 21, 2022, 09:15:21 AM

Looking good now. One thing about bits is use the cheap ones for testing because they snap just as easy as good ones when something goes wrong. I snapped a brand new $35 Amana bit in 10 seconds setting mine up because of an alarm on my closed loop stepper driver was set wrong. I find once you get things worked out you can't beat the Amana bits. Your wife and children will thank you for going with the spindle. So quiet compared to routers and won't burn up after a couple hundred hours. A spindle will have longer life if you let it run some to warm up before starting to cut. Can't wait to see it finished. Building a CNC machine sure is a fun learning process.

Crusarius · May 21, 2022, 04:05:26 PM

You are so right. Very fun and rewarding experience. My wife wants me to build her a bin storage rack on the landing of our stairs. I figure the shelves are going to be plain boring pine glued up. But the top I am thinking making some very large puzzle pieces on the CNC and putting them together.

I wonder if there would be any demand for CNC services in the area? Friend of mine wants me to plasma cut a large sign for his new endeavor.

Crusarius · May 21, 2022, 04:12:57 PM

I did a little more work on getting the Z axis working right. I was concerned that the weight of the steel plates and the weight of the spindle was going to be a problem. So, I decided to temporarily hook everything up just to cycle it and see how it worked.

I have an 8mm lead screw I am using for movement. It makes an awful lot of noise going up not so bad going down. I feel that the lifespan of the brass nut will be very short, so I am searching for other options.

I think I may actually buy one of these.
CNC Linear Motion Rail Guide 200mm Stroke Ball Screw Electric Linear Stage Actuator with Dust Cover for Nema23 Stepper Motor X Axis CNC Router: Amazon.com: Industrial & Scientific

I also decided for personal use I don't think I need a 12' long table. It was kool to say I had one but shop space did not allow it to work so now I have a 6'x6' table. Speaking of that I need to make the table.

Crusarius · May 21, 2022, 04:15:18 PM

P.S. I know the spindle is upside down. I decided to do that in case something failed it would not drop on the important part

And I wanted to do a custom monogram on the shop ceiling.....

Which one do you believe

Ljohnsaw · May 21, 2022, 06:32:20 PM

Quote from: Crusarius on May 21, 2022, 04:12:57 PMIt makes an awful lot of noise going up not so bad going down.

What about installing a couple gas shocks to help with counterbalancing all that weight?

Crusarius · May 21, 2022, 08:34:21 PM

I think a ball screw is the answer. The lead screw does not have an anti backlash nut so there is probably .020 of slop in the thread.

The motor can lift the load without even struggling. I am not sure if I have the nut centered or if it is side loaded. I am guessing it is not straight. and my motor shaft adapter got machined from both ends so that is off a little to. Combination of everything makes it not work great.

Definitely want to use ball screw though. That entire moving section is probably 25 pounds.

Crusarius · May 28, 2022, 10:14:41 PM

Made a little more progress today. Put the new Z axis I ordered on and managed to get the Z and X stepper motors mounted. The Z axis has 200mm of stroke. I was shooting for 5" of stroke but ended up with almost 8". Once I get the bed built, I will actually know how much of that stroke I will use. Right now, I bet I could configure it to be able to put a 7" board on the table without trying real hard.

Here is an overall picture of the Z, and X axis drive motor.

Here is what it looks like on the back side with the X axis drive.

I am not sure if I need it or not but, I may add a jack shaft and a second drive belt. I am not sure it is necessary, but if it is I can flip the motor mount upside down and add the second drive setup.

I think I may be down to moving all the electronics to their final resting places and wiring it all up now. Along with building the table.

Getting really excited to see the end of this project.

Walnut Beast · May 28, 2022, 10:17:47 PM

Looking great!

Crusarius · June 01, 2022, 09:33:30 PM

Thanks,

Between all my running around today trying to get my jeep inspected and registered I managed to at least get a little bit done.

Here is the control panel. I really am trying very hard to keep this thing clean and not have a wiring nightmare like I am notorious for.

I have the VFD for the spindle on the far left, then I added an outlet that is controlled off the blue switch for anything like a vacuum or a coolant pump. The other three switches power up the controller, the stepper drivers / motors, and the spindle. Then the standalone controller.

I figured having a separate power for all of those would be nice since it was a pretty decent crack when I was plugging it all in at once. I also like the idea of having a shutoff for when I am changing tools in the spindle. I never trust the spindle to stay off when it is controlled by a computer.

Hopefully I will not be popping the breaker with the current setup.

I did just suddenly have a thought. I could run 220 line into the control panel then split it into 2 110 circuits. Is that a good idea or not? Shoot, if I did that I could have gotten a 220 spindle. oh well to late for that now.

Crusarius · June 06, 2022, 08:35:27 PM

I managed to get the control panel all squared away and mounted on the gantry. With the limited real estate I have to work with I added a hinge to the mount. now I can have it out so the X and Y arrows on the keyboard match the table and flip it out of the way when I don't need it.

In the operate position

I may end up moving the VFD to a slightly different location since it really hangs out there. But for now we will see how it works. Hopefully tomorrow I can get some more wiring done.

In the stowed position

Ljohnsaw · June 06, 2022, 09:38:30 PM

Quote from: Crusarius on June 06, 2022, 08:35:27 PMI may end up moving the VFD to a slightly different location since it really hangs out there.

Do you need to get into it? What about putting it on the back of the display? Or below and as close to the hinge as possible?

21incher · June 06, 2022, 10:46:56 PM

Those cheap vfds make a lot of electrical noise and should be as far from the controller as possible. The controller should have outputs to control it remotely with code. Add a spin up delay to your g code or set it in the controller if possible. 15 mm belts need a very light gantry I found on that sled I built. They become rubbery under acceleration and can bounce from chip load that seems to be from the cords being pulled around small drive pulleys front and back when wrapped for a drive system. I read this happens if the belts are tensioned over 1/15 of their breaking strength. Have fun.

Crusarius · June 07, 2022, 08:29:41 AM

ljohnson, those are all the places I was considering.

21, have you actually witnessed the 15mm belt issues? I have read alot but have yet to notice any issues with them.

wkf94025 · June 07, 2022, 04:18:58 PM

Fascinating reading, and I hope the evolution and documentation continue.

If I may ask a couple potentially obnoxious questions (obnoxious since FUN is obviously a big part of the motivation and experience): (1) what would it cost to buy a CNC setup as capable as what you'll end up with? (2) what are your approximate cost of goods for the alu-based version currently working? If these are annoying or uncomfortable questions, just ignore them.

Independent of the economics, the FUN is unmistakable. Congrats.

Crusarius · June 07, 2022, 05:28:34 PM

I do not know what it would be worth for sure. but I know I can't afford one

Plus the size, weight, and power requirements of something like a weeke or biesse usually involve 3 phase power. No way do I have enough space in my shop for a full size machine.

I have no idea what this has cost me since I had some parts and materials around from a previous project.

Only thing I can say for sure is two 24' sticks of 2x2x.120 wall aluminum tubing cost me over $400.

rusticretreater · June 07, 2022, 08:39:00 PM

I build my own CNC and if you are mechanically and electrically inclined, I recommend it. I was able to build a large table machine, 3x6 on a 4x8 base with room to sit things, for 1/2 price. It was amazing right from the start even with the hiccups, the tweaking and repair/mods.

Then the next thing you do is use your cnc to cut out improved parts to swap out or make a second machine.

If things don't work right, you know who to talk to, customer service is great and the techs don't give up until the problem is fixed! ;D :D 8)

Crusarius · June 07, 2022, 08:51:26 PM

The mechanical end was really easy for me with my fabrication background. The electrical was very much new territory. It really is more intimidating than difficult.

My biggest issue is just figuring out how to run the wires to keep the entire thing clean and safe.

21incher · June 07, 2022, 09:35:02 PM

Yes I can see it in the Y of my slab flatner with the (2) 7ft 15mm belts. The x has none of the bounce with the lead screw. My gantry is about 75 pounds with the 3hp spindle, dust collection, and steppers. My first Router I ran 1 inch wide T10 belts tensioned to probably 400 pounds with 2 1/2 inch drive pulleys and wasn't affected by chip load or acceleration during direction change. Was going to use them on the flatner but was to cheap to buy the pulleys. Luckily my slab toy doesn't need accuracy. I definitely won't try using them on the bigger version. I learn a lot from my mistakes. The x carve and machines like that don't seem to have issues but their gantry are less then 20 pounds with small routers. Let me know how yours work out.

Crusarius · June 08, 2022, 08:35:57 AM

I am going to need to take it apart to do the wiring. I will see what I can do to weigh it then. I am very curious if I am going to have the same issue.

that is a 2.2kw spindle on it so that's roughly 20 pounds right there.

Crusarius · July 06, 2022, 07:02:08 PM

well since I did not take the entire assembly apart, I did not get any weights. I can pick the entire gantry up and move it by myself. Only reason I ask for help is its a little awkward.

I did manage to get the rewiring mostly done. I will get pics of that tomorrow I hope.

I finally decided I needed a table, so I spent some time working on that today.

I am halfway through building the table. Unfortunately, I kinda oopsed when I needed to change the design for the material I had. So tomorrow the first thing I need to do is cut 3" off the width of the table and then build some legs for it. if everything goes right the CNC will be mounted to the table and the t-tracks will be placed and ready for MDF infill.

Table is being built out of 2x4 rough cut lumber that I harvested, milled, and dried. First layer on top of the table is 5/8" OSB which the t-track is getting screwed to and then there will be infill of 3/4" MDF in between the t-tracks. The infill will be my sacrificial board so I can machine into it.

Since the t-track is only about a 1/4" tall I will have a good 1/2" of sacrificial board to play with before I cut into the t-tracks. will also be a nice gauge for when I need to replace it.

I am also toying with a winch idea to be able to lift the CNC up into the trusses and leave the table as an assembly table. I think if I set it up with dowel pins it will be real easy to remove and install the CNC but also leave me a working table for any other project.

The other kool thing about removing the CNC is I can always put a metal tray for a plasma water table.

oh so many ideas...

I will work on getting pictures posted soon. Still have some scary looking wiring to clean up but really close to being done.