Jon's 3D Printing and RPI Adventure: October 2018

Enders 3 Game

The Ender-3 from Creality

About 6 months ago I realized that I had spent something like 2 weeks trying to make my M3D Mini print something. I had done many many hours of work and had nothing usable to show for it. Everything was like cotton candy strength shapes. Useless. And I had tried a LOT of things. Replaced all of the parts I could replace. Nothing was working. And I was beginning to think that I was like that guy who keeps doing the same thing expecting different results.

So I boxed the entire thing up and put it away. Thinking I would come back to it later.

Instead. I happen to mention to my financial guy that I was going to do 3D printing when I retired and he laughed and called in his co-worker who proceeded to talk my ear off about his new 3D printer and how great it was and the things that he was designing. Then he showed me a puzzle box he had made. He said his printer was the greatest and the puzzle box certainly looked GREAT. (not perfect, mind you, but bigger and better than any thing I have managed).

Then he clinched it by saying, "I have a Creality Ender 3. You can order one second day delivery on Amazon Prime right now for $229.00"

Man, that is like 25% of the price for things I have been looking at. The deal? This is the open source printer. The standard one for hobbyists. This could be good or bad. Bad because it doesn't have a professional design team making special design things for you. Good because it has simple to source parts from lots of manufacturers and you can print or build most of the parts yourself and the thing is constantly (like every few months) improving as one of the many open source companies that work on them improve some little thing.

The other good/bad thing--- you have to assemble it yourself. Like a puzzle. Or a giant fighting robot.

So.... Mine came on Sunday.

It took me about 4 hours to assemble it (I was going very slowly. It only takes like 10 minutes in the You Tube Video).

Here is the scoop. Special things you should know about assembling the September 2018 revision of the Ender 3.

Watch a You Tube Assembly video. I like this one because the guy doing it has a british accent. This makes everything seem more reasonable and correct.
Watch the You Tube Video again. Really.
Go open the box and get acquainted with all of the parts. I find it helps to have a surface where I can lay everything out where I can see it. So when it is time to find the 4 5x48 screws with washers, I can do that easily.
Step 1 is to put on the vertical support beams. This step isn't difficult. Do have the video keyed up, however, and watch each step before you try it. Also helps to have the pictures from the quick start guide there to sort of help you on your way.
The main support elements are these square sided extruded aluminum bars. Things slide into them and tighten using a sort of funny flat mushroom shaped nut that slips into the triangle holes running down the middle of the sides of each bar. This lets you slide things down and then tighten. BUT, you need to have the nuts turned such that the triangle shapes fit across the groove. If you let them turn, they just slip out of the hole and don't catch on anything. All of the instructions say to slide them in from the end being careful to keep them straight. This is hard to do. I found that I needed to have the just the right amount of tight (as tight as they could be and still slide in) and then guide them straight with a little screw driver or other small tool. The thing is, they should be easier than that. They look like they are designed such that you can just push them up to the slot at the location you desire and then when you tighten the bolts, the nuts will rotate and lock in place. Do they do that? I don't know. I guess I should go try it, but I think I don't want to take the thing apart just now...
Zed. Zed means Zee in British. See, I told you the British accent You Tube Video would be fun!
The Z-Axis ("Zed Axis") stop bracket. This is a bracket that slides on to one of the upright extruded bars and tightens using those funny mushroom nuts. The directions say to secure it such that the bottom of the bracket is just about 32mm above the bottom of the printer base. I went and got my metric ruler. When I measured, I found that the bracket quits sliding down the rail at about 45mm. It is blocked from sliding down further by a little plastic tab that has evidently been added to the standard part since the written directions AND the You Tube Video have been made. However, it is pretty clear that the tab is there to make it easy to decide where the Z-axis stop should be. So I just went with it. That was a mistake. It turns out that if you search around the internets some more. (look for "that thing sticking out is stopping the Z stop from being low enough"). Everyone agrees that that little tab just came into being in the July build and if you are going to get the bed height set right you have to cut it off. So do that.
The X-axis bar assembly. The printed directions and the directions that are on the little USB key that is hidden in the spare parts bag are not the way to go on this one. Follow the British You Tube Video closely. That works well. Oh, and you have to push pretty hard to get the rolling hot end onto the bar. Just do it carefully.
The Z axis stepper engine attaches with 2 bolts. The video says so. One of the sets of directions says so. But another one implies that you only use one bolt here. I am thinking that using one bolt helps with the alignment of the long vertical Z-axis stepper screw. This thing is 12 inches long and runs up the side. It makes the X-axis bar lift in the Z-axis. Magic !!
It seems like they used a different style electrical connector for each plug. Making you have to figure out each one separately. Oh, and the last one you have to plug in is sort of interior and appears to be impossible to do. But just push it in there and hope for the best.

But after all of that, it really was pretty fun to build the thing myself. And now I do know a lot more about how this kind of printer works. Time to go see if it will print something.

Bed Height:

I knew that getting the starting bed height right was going to be the first hard thing. And I just couldn't do it. I could not raise the bed high enough with the fine adjustment leveling screws. I needed to change the height of the Z-axis stop, but I couldn't get that any lower because of that little plastic tab. This is when I consulted the internets and it informed me to clip that bad boy right off. Luckily, I could do it with a pair of dikes in place (I didn't have to take the entire thing apart and start over). That done, I could level and get the right starting height and I launched the test model build that they provided with the test PLA that they provided.

Some things I found:

1) There isn't enough test PLA provided to print the test model.

2) Switching filament in the middle of a print with this printer is EASY. takes like 60 seconds and just works.

3) My test dog turned out great.

4) The untreated Bed is too damn sticky. You can't get the attachment layer of PLA off of the damn thing. MUST USE BLUE TAPE TO MAKE THINGS TAKE OFF ABLE.

And now for a bunch of pictures.