Galaxius' Printer

I backed Robo3D during the Kickstarter because of it's build, price, heated bed, and the guys had big dreams. 10x9x8" for under $700, awesome. So I made my pledge and waited, the delivery date was pushed a number of times due to design issues, teething problems, improvements, and trying to build the best printer they could. It was a Kickstarter so I was patient and began to investigate the forum. Now I was getting excited and glad I backed Robo3D, the forum members were awesome. I read everything I could on the forum, Googled heaps of other 3D printing related articles, looked for filament suppliers, and trolled through Thingiverse. I hoped the printer would arrive before Christmas but alas it didn't, then I got the shipping number and it arrived late January. Man, I was like a kid in a candy shop. I got it home, unboxed it, set it up, downloaded and configured the software (Repetier Host + Slic3r), connected to the printer and began calibrating the Z height. First problem encountered, my bed wasn't level from front to back. Well, it's time for my first mod since the first layer is the most important layer and an unlevel bed just won't do.

I used the o-ring solution for fine tuning, though I couldn't find the correct sized o-rings so I cut down a rubber gromet, worked like a charm. I'm still using this mod and will do until I print a linear rod modification for the Y axis.


Now that my bed was level I completed the Z height calibration and it was time to do some test prints with the sample of black PLA that came with the printer. When I pulled the first print off the bed I thought, man this thing is awesome, but also realised it would be quite a journey to perfect the print by way of slicer and hardware tweaks. The one on the left was the first print, followed by the one on the right after a few slicer tweaks.


I ordered 2 spools of PLA and 2 spools of ABS from www.3dprintergear.com.au and when it arrived it was test print time again. The filament was better but I was still having issues that I couldn't fix no mater the amount of slicer tweaking. The prints of natural PLA were coming out milky looking (easily visible in the following pics) and I was getting what looked like burnt bits. I later realised the issues were due to the stock hotend.

Time to print some upgrades. I wanted to take the cover off so I had better access to the printer for tweaking and upgrading. My first upgrades were to stabilise the cable bundle.
http://www.thingiverse.com/thing:209034
http://www.thingiverse.com/thing:227307


I was suffering issues with hotend temperature fluctuation and I thought it could have been part of my print quality issues so I designed a fan duct for the Robo3D. It turned out fantastic but now that it directed the air precisely to the print hed the temperature would drop 30C where the too cold to extrude temperature was being triggered. Other people were not having this issue when using my duct so began the next lot of trouble shooting. I ended up manually ramping up the fan speed gradually to allow the hotend to maintain temperature.
http://www.thingiverse.com/thing:270506

 

After more test prints and slicer tweaks I had to print something other than a mod or test. I printed an owl and was fairly dissapointed by the result, I just wanted it to be good. I had a couple failures which turned out to be the sub par hobbed bolt clogging which I later replaced (below), and on this print it clogged just before finishing the ear tips. The owl had burnt brown stuff on it mainly on the side away from the fan.
http://www.thingiverse.com/thing:18218

 

The Hexagon hotend had come onto the scene recently and was undergoing beta testing for its silicon jacket and I managed to scrape in to the list of beta testers. When it arrived it was like the day I received my Robo3D, but I had my doubts that this would fix any of my issues. Well wasn't I wrong. It was like changing from candles to LEDs for lighting your home. All my hotend issues were gone, and now I have the option for a future bowden upgrade since it can handle both bowden and direct input (to use bowden you remove the brass grommet in the top of the coldend and screw in an M6 1mm pitch pushfit connector. The Hexagon is quite a bit shorter than the stock hotend, 55.4mm to the nozzle tip as opposed to 66mm.

Hexagon thread. http://forums.robo3dprinter.com/index.php?threads/hexagon-hot-end.1888/
Hexagon assembly video.


If you have the silicon jacket it does a good job of holding the thermistor in the heater block. I used a zippy tie to hold the thermistor wires more securely and to keep the bundled to the heater cartridge wires. Make sure you poke the heater cartridge and thermistor through the jacket holes and fit them to the heater block before as you fit the jacket to the block so you don't bend the wires, it's a bit fiddly.

To install the Hexagon disconnect your X axis limit switch and any restraints holding your cable bundle then life off your X carriage. Remove the existing hotend and follow the cables back so you know where to connect the Hexagon. The Hexagon wires are just long enough to use without extending. The coldend fan is wired directly to the 12v out (circled red). The Hexagon can be bolted directly into the existing mount without using the supplied mounting plate. Make sure you buy some socket head bolts to use instead of the stock screws (25mm M3 if I recall correctly??). The coldend 40mm cooling fan can be mounted directly to the side of the X carriage with a single screw. I have the silicon jacket so blowing on the heater block is not a problem, if you don't have the jacket you can insulate the heater block with some Permatex Ultra Copper as highly recommended by others. Use this fan mount for the print cooling fan. http://www.thingiverse.com/thing:226998
You will need to use zippy ties or button head bolts to fit the fan and maintain clearance. When you fit the fan bracket I recommend replacing the stock extruder mounting screws with socket heads (20mm or 25mm M4). I'm only using socket heads now as they're much much easier to work with. I bought 10 of every size between 8mm and 40mm M3 in stainless steel and a heap of nyloc nuts, they're not very expensive.

 

Time to print a Yoda head. Epic fail. The stock hobbed bolt was rubbish, time to upgrade that. Got a 60mm (55mm is enough) hobbed bolt via ebay with a recessed hob 15mm from the base of the bolt head. I also bought a bolt with the hob at 25mm to reverse it with the head in the extruder gear but 25mm is not enough, 28mm should do the trick though. I shimmed the nut in the extruder gear and added an extra nut. I still had to adjust my retraction settings to stop filament grinding (accelleration, speed, length, and when to retract) but the bolt alone helped immensely. I made the upgrade to dual print fans and purchased Simplify3D shorlty after.
http://www.thingiverse.com/thing:226998





With dual print fans the heated bed now caused the poly fuse to trip. This was later address by Robo3D by introduction of a RAMPS board cooling fan. I printed the bracked from Thingiverse and now this issues is addressed, though other mods to better address this issue are in the pipeline. I have circle where the fan connects to on the RAMPS board in red, notice the polarity orientation. The fan is mounted fairly central over the RAMPS board as it's a bit tricky to find space for the brackets' feet but it does blow air over the inner most poly fuse (there the big yellow square things) and the mosfet.
http://www.thingiverse.com/thing:166045



Since my printer arrived in January I've learnt Repetier Host + Slic3r, modified and updated the firmware, upgraded the hotend, learnt 3D CAD (ongoing), designed various things including my fan duct for the Robo3D, installed a 2nd print cooling fan, installed a RAMPS fan, learnt Simplify3D (ongoing), and more. I couldn't have gotten this far without the fantastic forum users, I won't mention names but most will know who they are, thank you. I'm glad I've had the opportunity to in-turn help others new to the Robo3D family.

 

Great work Galaxius

 

That burnt stuff on that owl could be due to your nozzle builds up with oil from the melting filament. You need to clean it off by swiping your nozzle with a cloth before printing while it's hot. It will drip onto the print and give your those results. Run PLA at 190, but some filament might be less oily giving you better results. Try different manufacturers of filament and you will see that some filament is superior to others.

 

I wiped and wiped it. That was with the stock hotend. I've had no issues at all since changing to the Hexagon.

 

New low profile fan duct uploaded to thingiverse. http://www.thingiverse.com/thing:431160
Angle adjustable, screwless attachment to the X carriage, and fits with the Hexagon hotend.

 

My Z stabiliser design. I didn't like the other ones available so designed my own. I haven't had the need to install them but I wanted spares just in case I break one whilst the printer is on its side so I can tinker underneath. The one on the right is dirty from doing a test fit on some 8mm smooth rod. http://www.thingiverse.com/thing:432158

 

I find the (naturally) weakest point on them is the transition from horizontal to vertical. Creates a huge stress concentration

 

@Galaxius I just noticed this thread and the owl pictures with black/brown spots - are you sure you don't have the infamous cracked PTFE tube problem in the original cheap hotend? Some of us have experienced this - http://forums.robo3dprinter.com/index.php?threads/black-molten-plastic-in-print.1605/
I know you have replaced it with Hexagon by now, so it's not an issue any more (I'm using E3D myself). But out of curiosity, did you inspect your old hotend and did you see any seepage of molten plastic from under the kapton tape above the heat block?

 

I didn't inspect the hotend. Should I, and if it does have a cracked PTFE tube should I log a support request even though I've replaced it myself? I received my printer at the end is January.
@Mike Kelly?

 

That's your call I suppose. I'm not sure what they'd say on that. When mine cracked they sent me new ptfe inserts.

 

No harm in asking I guess. Thanks.

 

Upgrade to the Reprap Full Graphic Smart Controller. The best $20 I've spent, bought via ebay.
I tried printing the case in white PLA, which I've since found out is the hardest colour to print with, but had many failures. I swapped back to my roll of natural PLA and was successful first go. The knobs and button are printed in blue PLA. My make is here: http://www.thingiverse.com/make:102272
The bracket I designed and used for mounting is here: http://www.thingiverse.com/thing:537731

The only thing I don't like about the screen is that you can see only so much of the filenames, it would be nice if the UI would scroll the highlighted filename.

 

How I apply hairspray to the bed to greatly reduce over spray of the hairspray, comprende. lol

 

Smooth rod Y axis upgrade by @tonycstech
http://www.thingiverse.com/make:107124
Cable chain remix
http://www.thingiverse.com/thing:595308
Rerouted the bed cables and added high amp connectors (XT60 connector for the bed heater and a 2mm HTC for the Thermistor). I'm using silicon coated wire through the cable chain, very flexible and handles 200C, 16 gauge for the heater and 24 gauge for the Thermistor. Wire and connectors came from hobbyking.com. The tape used is kapton tape.

 

Real nice looking man, keep up the good work

 

Open heart surgery after the heatsink, heat block, and nozzle came loose. Heatsink I can understand as the heat block orientation meant the cables were pulling on it, ever so slightly, in a loosening direction so when it was heated it must have finally come undone. What a mess.
Heated to 210 and used the small flat screw driver to remove the silicon jacket. I can't get the heat element out as it's stuck with filament. I'm cleaning the inside of the silicon jacket with the flat screw driver. I tightened the nozzle and heatsink whilst heated to 220 though the heat block cools rapidly once tools are applied. What a pain in the A.

 

Ouch man! I hope you get it fixed and running again soon.