It was just an idea. I was wondering if it would benefit the design. Actually, I'm planning to build something similar to the C-Bot, but using a maximum of OpenBuilds parts. Because of the V-Slot gantry plate design, I thought it would be easier to use 20x60 profiles in order to attach the belt to the plate.

 

Got almost all of my cuts done today. I found using gun oil on the metal during the cuts was critical due to heat. With this $5 10" blade I had great luck using a cheapo $120 Ryobi miter saw: http://www.homedepot.com/p/Diablo-1...MERCH=RV-_-rv_nav_plp_rr-_-NA-_-202831056-_-N

The blade saw little to no wear. The cuts came out about as good as Openbuilds cut quality.

I did make one mistake and didn't have enough to do the last 303mm cut but I ordered a 20x40 500mm extrusion with Priority mail shipping today so hopefully Openbuilds ships quickly!

Anyone have a source for cheap F623 bearings in the US? OK, I'm off to frame up my C-bot

 

Well I started my build today. After I got my parts sorted I got to this line in the instructions...

Load Idler pieces and CoreXY Ends with Flanged bearings
Step 2: stack 2 flanged bearings with a M3 washer between them and it load into the assembly (easier said than done)

After a couple of tries I decided that it was more difficult than it needed to be so this is my method of building Idler pulleys out of flanged bearings and washers.

Step one Gather your parts plus a roll of tape and a M3 nut.

Step 2 Stack your bearings and washer (I used some m3 nylon washers I had on hand) in the proper order on a 3x25mm bolt

Step 3 Secure your stack with a m3 nut. I used a thumb nut for ease of removal but any m3 will work.

Step 4 Carefully wind a 4mm strip of tape around your Idler Pulley.

Step 5 Remove from bolt and insert assembly into part.


Step 6 Use a pair of pliers or tweezers to remove the tape.

Step 7 Do the happy dance.

Thanks Mike

 

Excellent solution to a tricky assembly, thanks for sharing.

Tweakie.

 

I've made an initial model of the C-Bot with a 12x12 bed and an E3d Chimera dual extrusion hot end.
This will help me plan out my cuts for the v-rail to make sure I have coverage of the whole bed with the dual nozzles.

I have 2 question though:
1. How do I attach the heated bed to the Z platform?

2. Is the front top beam only held in by two 90 deg corners? If not how should I attach the top beam? See pictures to see where I'm talking about.

I'm planning on making a 3d web viewer that lets you automatically size a 3d model of the C-bot printer and interactively shows you the length of extrusions you need for the bed size you choose. I currently have a rigged version of the printer in Maya but will add blendshapes for sizing the bed and rails automatically.

 

Beat me to it! I used 4 90 corners AND a 5 hole plate on the inside. I'm printing more now so I can use a 90 degree corner and 5 hole plate at every location possible to ensure the frame is as rigid as possible since I'm using plastic 90's and plastic 5 hole plates. Eventually plan to upgrade them to aluminum though.

Still in the middle of planning my assembly but here is what I have so far(nothing is aligned yet):



I'm wondering whether mounting the 5 hole plates like I have shown in picture or move them down to second T slot will make any difference as far as rigidity? Seems like the way I have it is ideal but I'd like to hear other opinions.

 

Thanks Carl and Haxored for the clarification, the pictures are especially helpful. I can't wait to get this thing printing!

 

Hi,

Sorry in advance for the noob question.

Would there be a difference between the regular Tee Nuts and the Drop In Tee Nuts? I mean aside from the cost.. Do the regular ones grip or function better?

Thanks

 

Thank you for your reply. I'm closely studying your design as well as a couple other ones. Still trying to decide on the build dimensions and lead screw count (2 or 3), though I'm leaning toward 12x12x18" and 3 lead screws.

Thank you also for your great assembly doc. It really helps trying to visualize how all the pieces fit together ;-)

 

@Carl Feniak did you use any timing pulleys ? I saw many CoreXY printers using a combination of smooth and timing pulleys. Is there any advantages of doing that ?

 

Ok, thank's for your answer Just another small (and maybe a bit stupid) question : which bracket between this one and that one do you recommend to use in this kind of build ? Is there a real difference between these brackets ?

 

I'm starting to print the parts for my C-Bot. Is there a list of how many of each part is needed? I figure most will be one, but like the 90 corner piece I know there are going to be several of those.

 

U might be interested in these bottom corner pieces. I used these on mine and it is solid as a rock. Must tap the bottom holes in the legs - use one hole for a foot.
There is one pair in the file, need 2 sets

 

Thanks. Will give them a try. Just a FYI, Repetier is reporting them as non-manifold. Will run them through netfabb to take care of it.

 

Sorry, I just put them into one file and didn't chk them. They were good separately. have fun.
Here is a good one for anybody else.

 

Thanks. I found that I can print 15 at once on my printer so will just go ahead and do that many plus Ruggb's. So for everything else, just one of each .stl file?

 

But if you look at the total time for printing all at once vs one at a time, in my experience, it takes less doing all at once. Besides, I just set it up to print when I head to bed and they are done in the morning.

 

I want to use this design to make a demo with larger industrial servo motors. Since the motors are larger and heavier I redesigned the motor mounts to use metal plates. The plates can be flipped for the other side and different spacers are used to shift the location of the belt. Attached are some of modeled picture. All other parts will be from the existing design and will be 3d printed. Please comment if I might be missing something where my design may not work. Thanks!!!

 

I like the incorporation of the horizontal crossbeam into the motor mount.

 

Yes the motors are big but it is the smallest motor that I have for demo. Check the picture below. The reason I what to make a CoreXY is so I can make a small demo without having to move the motors. What is the proper offset required for the shaft? I only measured the distance in the original drawing for the motor mounts. Also since my shaft of the motor is larger I had to use a 20 teeth GT2 sprocket. Should I make a bigger offset to compensate?

 

Hi Carl,

Could you make a note on the BOM about the Black Anodized 90 Degree corners?
Apparently the normal M5x10mm Socket Cap Screws do not fit in the Black Angle Corner Connector pieces. They require the M5x8mm low profile screws so it would be nice to have those in the BOM if you go with the aluminum corners.

Do the 90 deg cast corners and printed corners take the regular cap screws?

 

Hello All,

I've uploaded a new version of the Assembly document as a PDF with an image that shows the name of most of the printed elements and where they go on the printer. I've also cleaned up typos, formatting and spacing for clarity as well as added some tips from this forum on assembling the idlers.

I plan on creating more assembly images to help make this build as pain free as possible for people new to building 3d printers (like me). Let me know what you think!