Official 3DP Thread

[rifleman_btx]

Great stuff my friend :)

[Prowler901]

I have an opportunity for a modified Anet A8 which needs some coding for $200.

It’s a modified anet A8, has 220x220x240 build area (mm) heated bed, I changed it from direct drive to bowden, changed the power supply to an atx, changed the control board to a mks gen 1.4, all the upgrades will make it print better once the code is installed

Any thoughts on it?

I have an Anet A8. I bought the kit and have printed many upgrades for it. It is not a bad printer for the price. It sounds like he has added some decent upgrades. A Bowden is something I want to do with mine. Does he say what he has put on the hot end?

In my opinion that's not a bad price with the upgraded parts. I paid $170 for mine and had to build it.

[bandit]

RCjetdude

I don’t have any specific experience with that model. It sounds like there is some work involved in getting it working. You might want to download Cura and see if that printer is supported. The one thing that did catch my eye is the Bowden extruder upgrade. This is a topic of discussion in the printing world. With most printers, the moving extruder assembly has the heated element, a couple of fans and a filament feed motor. The motor pulls thr filament off the spool and feeds it into the extruder. The distance from the feed motor and extruder is about 1inch. In a Bowden setup the motor is relocated to the side wall. The filament is forced through a guide tube to extruder.Here the distance could be 2 feet. The theory here is that by moving the motor, the head assembly gets lighter. Less mass means you can move faster and print faster. The ability to print accurately and cleanly is tied to the ability to start and stop extrusion exactly when you need to. The discussion is about how much the filament compresses with the Bowden. Also how much does it stretch. This becomes really evident when the extruder moves to a new location. Say if you were printing a table for your daughters play house. You have the four legs sticking up in the air. If you just stop extruding and move, the nozzle will ooze and leave stringers between the legs at each layer. The slicer attempts to control this by retracting a programmed amount at a certain speed. You keep playing with these numbers until the stringers go away. If the filament stretches and compresses, it makes tuning more difficult. There are many people who say it works fine so it’s probably ok. One thing for sure, you wouldn’t be able to print a rubber like material. And as for being able to print faster, under some circumstances, that may be true, but print speed is more than motor speed. The currently extruded plastic has to cool and become stable before the next layer. The slicer software looks at the print time for each layer and when it gets shorter than the time to cool, it purposely slows down the print speed. This is a long winded answer to your question, but the printer will probably be fine and it’s an inexpensive way to get started.

[Prowler901]

Bandit speaks wisely. Thanks for posting all the detailed explanations that you have. You've put a lot of time and effort in to sharing it with us, and it is very appreciated. :Cool:

[RCjetdude]

There is so much to think about it is a wonder anything ever turns out. This Anet A8 seems like a good price with the mods. A guy I work with has it for sale. He has a 3D printing side business and seems legit. I am just a little concerned about the coding part but it's also one way to learn. Dive in head first. I have been really looking at a Creality CR-10S but for a third the price of it I figured I would look closer at what he's got first. I also need a decent computer. Planning to run the Fusion 360 software on it. Any recommendations on that? I've looked at the minimum system requirements but can't translate a processor to what I am seeing available. I assume most available computers are capable of running it.

[Sky Wolf]

Found a few 3D print channels on YouTube. This guy has a lot of followers.

https://youtu.be/TMlF8bl4MdQ

[bandit]

Fusion 360 is pretty good. It’s put out by autodesk which a good company. Several people at work use it for home

[bandit]

I know all of this is a lot to take in and I don’t want to scare anyone off, but this is the reality of 3D printing. If you have ever seen “The Martian” with Matt Damon, there is a scene later in the movie where Mitch Henderson is telling Vincent Kapoor about all the things they have to do to the MAV to make it lighter. Vincent is getting upset and Mitch says “We haven’t even gotten to the bad part yet”

[RCjetdude]

On the Anet A8 a co-worker is selling he said it has an E3D v6 clone hot end as well and is supported on Cura. More foreign language stuff to me.

[Prowler901]

On the Anet A8 a co-worker is selling he said it has an E3D v6 clone hot end as well and is supported on Cura. More foreign language stuff to me.

That is a good hot end for this printer. It goes with what bandit was saying about making the hot end lighter which will improve print speed and quality. Cura is a decent slicer. But, I went ahead and bit the bullet and plunked down the $150 for Simplify 3D. My printing quality improved a lot after that.

[Dirty Dee]

I use Slic3r for my software. It's free, and so far has worked great for me

[RCjetdude]

I am learning a lot from this thread. Thanks all.

[andre]

I just did something new after owning my A8 for a year. Swapped spools during a print.

I was 59% in to the job when I determined I was about to run out.

Figured I'd try this.

First I paused the print.
Then I extracted the filament and loaded in a fresh spool.
Ran some new material through to be sure everything was correct and then resumed the print.

Success.

[RCjetdude]

I am getting an Anet A8. Not the one I was talking about earlier but another even better one that is all ready to go and comes with an enclosure. It has all the same mods that the other one had but this one has an aluminum frame. Should be up and running by next weekend.

[Prowler901]

Cool, that's a good one. :Cool: Much better with the aluminum frame. Much more rigid. Have fun. :)

[TiredIronGRB]

I am getting an Anet A8. Not the one I was talking about earlier but another even better one that is all ready to go and comes with an enclosure. It has all the same mods that the other one had but this one has an aluminum frame. Should be up and running by next weekend.

Making stuff we will be...

[Sky Wolf]

Very nice Steve! Excited to see what you start learning and producing.

[RCjetdude]

Me too.

[bandit]

So , i'm not sure what the best "Next Topic" should be. In my last post i inferred that the worst is yet to come in terms of information overload. I guess i'll cover the last of the fairly short topics which is design considerations for 3D parts.

1. Minimize the number of overhangs greater than 45 degrees.

I mentioned earlier that the printer cannot build horizontal surfaces that do not touch the build plate. A horizontal surface that starts higher up will require support structures added by the slicer from the plate to the horizontal surface. most printers can handle at least 45 degrees and many more can go up to 60 or higher. Where possible, i chamfer the overhang to the max angle my printer can handle. On thingverse website they have test prints that have various angles in the print just so you evaluate your printer. As you are designing your part, try and keep in the back of your mind how you are going to position the part on the build platform.

2. Break part into two separate pieces.

I do this sometimes because i can't solve the overhang issue. If you look at my picture, the engine cowls are printed. They are 150 mm in diameter and 125 mm tall. Only the last 10 mm at the top break the 45 degree rule and need support, but if you prints as one, the supports have to go the full 125 mm as its printed. By printing the top 10 mm as a separate part, i saved 2 hrs on print time. I could have inverted the part and put the small diameter on the plate. Then the needed support area would only be the first 10 mm of the print, but the support structures would be attached to the outside of the part and when broken away would leave a much rougher surface to have to be finished.

3. Use holes where possible.

Round circles, generally do not require support structures even though they break the 45 degree rule

4. When designing two parts that are supposed to fit together like a box and a lid, make sure you have at least .5 mm clearance.

5. Holes should be sized at least .5 mm larger than needed. this is especially true for smaller screw holes.

6. Add a 1-2 mm radius or filet for strength.

Before, i used the playhouse table example for the stringers explanation. where the legs of the table attach to the table top, add filet's. Without these, the legs would break off very easy. Because of the way its printed, the transition between the table top to the leg is really only held together by the number of perimeter layers(usually 2) plus some strength from your infill, which is not much. You could increase your infill, but it won't give you as much strength as adding the filet's and increased infill translates to longer build time.

7. On the surface that is going against the build platform, add a .5 mm filet. This helps getting the part off the build platform by giving you a place to insert the removal tool.

[Aros]

bandit, your willingness to offer immense knowledge on this topic is commendable and totally appreciated just so you know. Bravo Zulu!