5th Gen - Review and Head to Head with Rep 2

[American 3D Printing]

Since PLA can have a high melting point too in some instances, I just assumed the nozzle could hit 220-230c, even 220c I can get ABS to extrude at fine, so I'd give it a go!

Since for me getting those heatbeds in that size was a pain, I ended up finding the round 170mm ones for the kossel. They are just a thin pad with 3M tape on one side and do a remarkable job, and for $20 odd bucks they are a good buy and just stick on the bottom of the aluminium.

Returning filament is just impossible full stop, here is a conversation, word for word from my last return effort...

"Once you have broken the seal we can no longer accept returns"

"But I haven't broken the seal! it's still vacuum sealed, in the box, you sent the wrong colour!"

"Oh we are sorry, we will send you the right one"

"Do you want the old one back?"

"No"

"Really? I said I was more than happy to return it for a credit? "

"No you keep it"

Yes, I build with Taulman Nylon at 245°C in the Rep 2 all the time, it might even go 250, haven't tried it. Haven't tried it on the 5th Gen yet, but that seems like a logical test.

Interestingly, the 5th gen has a multi-step warm up process.

(1) Bed down, send extruder to front right corner, heat to 180°C.

(2) Send extruder to center, excruciatingly slow Z home procedure.

(3) Warm up to final temp (either 215°C or 230°C).

[American 3D Printing]

I don't know how much time I can devote to adding to this thread today, but we had a complete filament jam this morning, after trying the usual things to clear it I went ahead and completely disassembled the extruder, cleared the jam, reassembled the extruder and it is now working.

I took lots of pictures, and discovered a bunch of details about what makes it tick.

Yes it is a hall-effect sensor.

The round doo-dad that you have to line up when you put it onto the Z-carriage is a driven hobbed shaft.

The Z-lifts are from reversing the filament.

More to come!

[American 3D Printing]

Back to our exploration of the 5th Gen.

Sometimes it takes a while to notice stuff. I was watching the machine build, and it suddenly occurred to me, I didn't see an X axis motor. Huh? Okay, let's look a little closer:

This is looking up and to the left. You can't see it, but there are 2 pulleys up there at the end of the gantry, and the belt splits to go front and back.



Looking up and to the right, you see the same arrangement mirrored:

[American 3D Printing]

A slightly different angle reveals the rails the the gantry slides on for the Y axis.

[American 3D Printing]

Now I see the motors. There are 2 of them, identical, one on the upper left corner and the other at the upper right corner. At first I was thinking that they were only for the Y axis. But once you see the belt arrangement, it suddenly becomes clear that what they've done is reduce the moving mass at the business end by removing the X-axis motor from the gantry. The motors make either X or Y movement of the extruder according to which direction they turn! Fiendishly clever! I love the idea.

[American 3D Printing]

Now back to the head to head with the Rep 2.

One of our favorite builds is the T-Rex skull from Thingiverse. We make 50% sized ones for our givaway table, obviously the kids love them. Let's see how long it takes to build, and what the quality is.

As you can see, the jaw takes 33 minutes on the Rep 2.



Next up is the 5th Gen at 56 minutes.

[American 3D Printing]

HOWEVER, this is the first build where there does appear to be better build quality (appearance) on the one the 5th Gen built, on the left. Note I am using aftermarket (Filament Central, Chinese made) PLA on the 5th Gen and genuine Makerbot on the Rep 2.

[American 3D Printing]

Now to build the skull. The Rep 2 took 1 hour, 13 minutes.



And the 5th Gen took just over 2 hours:

[American 3D Printing]

As before, the T-Rex skull built on the 5th Gen (left) does appear smoother than the one built on the Rep 2:

[American 3D Printing]

I'm out of time for today. The current status is, the built plate still won't level, and it has been a week and a half since Makerbot said they'd send a new extruder to fix the build plate issue (I doubt it but will give them the benefit of the doubt). They did mail me a return label to send the old extruder back, in addition to the one they had emailed me. The sent me an email today asking if my issue was resolved, and I answered no, I still hadn't gotten the new extruder. I have to give them credit (along with Lulzbot, Type A Machines and Z-Morph), all these guys do have a clue when it comes to tech support. They all seem to try pretty hard, with varying effectiveness.

When I get some more time to post up, I will guide you through the dissected and figured-out smart extruder. It's a fascinating assembly, and like the rest of the 5th Gen, it has some cool approaches and some head-scratchers.