Building a 3D Printer

ya, i've been trying cura and slic3r and they get me very different results. thanks for the link.

 

btw, i figured out how to get the 3d models of mechs out of MWO.

 

So what direction do we start throwing the money?!

 

lets not get carried away yet. i get the new hotend tomorrow (USPS willing) and then once i get everything rebuilt i'll give one of these a try. Not all of them have a final scale file included so i do have to figure out how to assemble the final file or make use of alternate body parts (ie catapult k2 arms). I've got some instructions on how to do it for some other uses. I just have to figure out how to modify these steps for my own ends. I'm going to try to do an awesome first at a height of 80 mm. I'll get back to you in a few days if it works.

 

Dude, I was just messin. I know you have to at least make a few to make sure it works, lol. But when you are ready, let us know ^.^ Keep us updated as usual. That thing is so badass.

 

So the new hotend arrived. The heater it came with was not capable of hitting the temps needed for ABS despite the product description saying it could be used for it. So I swapped the ceramic heater out for the one that came in the original hotend. Due to the construction material of the new hotend it still had trouble hitting 230 degrees but when I turned the fan around to make it a puller instead of a pusher that was enough to reach the needed temps. Unfortunately I still can't get the thing to feed abs through the system. The extruder just keeps grinding out the side of the plastic wire instead of pushing it through the system. I think I have the problem located (how many times have i said that now?). I am hoping it is the bearing in the feed mechanism that puts pressure on the wire opposite of the gear that feeds it through. It does not seem to be spinning as free and easy as I'd like. Luckily these bearings are used in skate boards and so are pretty easy to get ahold of of. I ordered a new one (only a $1.23 but with $5 for shipping and handling) and now I just have to wait a few more days yet again. The problem might be compounded by the assembly that the bearing sits in. I will try opening it up a little bit more when the new bearing gets here if it doesn't spin easily once it's been installed.




i removed the fan from the first picture so that you could see the hot end. you can see the top of the fan (a little computer type fan) beneath the lagbolt in the second picture. it mounts just in front of the hotend assembly.

 

I think I found where someone was having their hot end drop temp before a print which was causeing some problems. supposedly there was somethign in the gcode was that was setting it to a lower temp and needed to be addressed in the slicer software.

 

So… I ordered a spool of PLA after giving up on figuring out why the ABS wouldn’t print with the new hotend. It finally showed up and I tried to get it fed into the hotend. It just wouldn’t feed all the way through to the nozzle. I took everything apart and it looked like there was some ABS still jammed in there. I ended up cooking the hotend in the oven to try and get it all out. When I did get it out I realized there was a liner in the main feed tube that was sized incorrectly. It was supposed to be a hotend for 3mm and instead it was apparently for 1.75mm. I checked my order form and for once this one isn’t my fault. They just sent the wrong thing. But I was impatient so after trying and failing to remove the liner I used the drill and cleaned the tube out that way. I tried again with the PLA. It fed fine but wouldn’t adhere to my print bed. My belief is because I don’t have a fan that can blow on the PLA as it leaves the nozzle. ABS needs a fan that blows on the hotend, PLA needs one that blows on the freshly extruded PLA. I gave up for the night but I had hopes that maybe I could get the ABS to work.

Next morning after watching the Raiders lose a game they could have won, I was back at it. I got the PLA pulled out of the hotend and fed the ABS back in. And… SUCCESS! Something is actually printing. I will have to find a fan and print a fan mount/nozzle for PLA but first I’ll print a couple things in ABS for fun. I'll probably try and do a print of an Awesome at some point today.

 

Any pics of stuff you've printed? I've thought about doing one of these kits, but 3D printers seem to vary a lot in the quality of the end product.

 

Here is what I printed today. It's a little elephant for a friend who is moving to Africa to volunteer for a few months. It is a little blobby. This is the first thing I've printed with the new hotend so I will have to dial it in a bit. Some of that is support material that I don't have completely removed as well. I printed this with ABS and a .35mm nozzle. It is a little under 2.5 inches tall.

 

Nice!

Glad to see things up and running again. Have you tried one without support? It doesn't look like any of the overhangs are particularly bad.

One thing with ABS is there are more finishing options which is nice.

What was the layer hight?

 

Layer height is .2 mm I believe for that one. Want to see something interesting though? I used SLIC3R to generate the gcode for that print job. Here is a different angle of it:

Look what happens when I use Cura to get the gcode:

A little bit different, eh? SLIC3R did a lot of simplification and even changed the angle of the head. I might be done using it. Cura recently updated and it seems to be working better now. I hate the support material it prints though. It is a real pain in the ass to remove. I haven't been able to get KISSlicer to work at all yet. It either stops working when you tell it generate the code or it provides useless code that just tells my printer to slam into the end stops over and over. I haven't found the the bit I need to change to fix that. I'm guessing I just need to flip the cooridinates around or something like that but until then I am stuck using Cura for most things.
On the plus side, I am liking the ABS. I just brush a little acetone over it to smooth things out and give it that nice gloss finish. It really helps bond everything together. I did get a spool of PLA but I need to print a fan mount and blower tube to focus the air on the PLA as it comes out of the nozzle. With ABS the fan just blows on the hotend. I tried printing PLA with everthing set up the same but it just won't adhere to the platform. I've adjusted the temp of the platform as well. I was running 110 degrees but discovered on accident (artifact left over from trying to print the PLA) that 90 works better for me. 110 was at the limit of what I was capable of heating the platform up to anyway and with temperatures dropping but all the windows and doors still open at my house it was really struggling to get up to temp.

 

Wow, that is pretty drastic. I haven't seen that big a difference in the testing I've looked at. Bizzare. Cudos to Cura. Hope the fix for kiss is a simple one, it would interesting to see a third version.

P.S. As an asside I was thinking about the PLA issues and was wondering if you tried slowing down the print speed as well. It may give a little more cooling time that you lack without a fan.

 

Ok guys. Sorry I haven't been putting updates here. The printer is working. I'm printing in PLA as well as the ABS now. The big problems with the slicers came down to the errors in the model. Some slicers aggressively try to fix problems while others just roll with what they get. Slic3r is one that tries to fix stuff. This is what caused the weird changes to models sliced with it. KISSlicer does an excellent job of telling you what the problems are so you can fix them and then slice them with the slicer of your choice. You can read about this on my blog (which I do update regularly). You can find it at http://sansthelight.wordpress.com It isn't only about 3d printing, but the vast majority of the posts so far have been about my trials and tribulations with the 3d printer and modeling.

 

Very cool stuff.

I like the light house. If you can get prints you are really happ with it may be quicker/cheaper/easier (or some combination) to do some resin casting instead of more prints to sell. If you are interested and haven't worked with that stuff before I have a few links I can post up for tutorials and supplies.

Glad to see you've got things running smooth for your investment. Happy printing!