I picked up a Rostock Max 3d printer a few weeks back. I wanted one to gain experience with a bowden hot end setup and a delta arm configuration. The build was pretty straight forward for me as I have built many 3d printers and even designed my own. I found the stock power supply did not provide enough power for me to heat the bed and maintain a constant temp on the hot end. I replaced it with a quality Corsair 600W supply that has a single 12V rail. Other than this and the fans I added the rest of the RMax is stock. If I had to pick one thing about the build that I did not like it would be the fitting of the arms to the aluminum u-joints. This required a lot of sanding, scraping and countless refits to get them to move with minimal friction.
My first prints turned out a lot worse than I was hoping for. However I was expecting more tuning than usual as I had read that Bowdens and delta’s required it to make decent prints. I was starting with PLA instead of ABS so it was even harder to tune the bowden setup. I needed to add a fan to cool the peek part of the hotend to stop the PLA from oozing up and causing a jam. I spent a lot of time on PLA prints and tuning but could just not get a result I was happy with. I decided to switch to ABS as it was supposed to be easier with the Rmax and its Bowden setup. Well I spent an equally frustrating amount of time trying to tweak the settings and not getting acceptable results. I was basing my tuning on the nozzle size of 0.5mm. In order to be sure I confirmed with John at SeeMeCNC that mine was indeed shipped with a 0.5mm nozzle.
Well it turns out my 0.5mm nozzle was not actually a 0.5mm nozzle. It was most likely a 0.7mm or larger. I figured out the nozzle wasn’t 0.5mm by extruding slowly into open air and waiting for it too cool then measuring the diameter. I was between 0.9 and 1mm in diameter. Normally a 0.5mm nozzle would measure about 0.6mm or so.
0.7mm nozzle on the left and 0.??? on the right
I was unable to print infill without making a mushy mess. (rmax on right with 0.5mm nozzle settings and Behemoth on right with proper infill extrusion width)
The mush was caused because I was using 0.5mm nozzle settings for extrusion and infill width in KISS. If you try and print infill with a width less than the nozzle diameter it won’t work. It makes sense why if you think about it. How can you possibly extrude infill at a diameter less than the nozzle diameter keeping in mind that infill typically bridges itself in open air. Mine would just fall apart as the flow calculation was wrong.
Once I dialed in the correct extrusion width into KISS the results were amazing. Infill was perfectly connected and layered. No more mushy mess!
I’d really like to be printing with a 0.5mm nozzle but I’ll have to wait until SeeMeCNC sends a replacement. For now I put on the 0.35mm nozzle. In this video you can see me printing the golvend tornado. I sliced it with KISS slicer at 0.25mm layer height. Printing at 20mm/s with feedrate at 150% and temp set to 230.
I sliced this with Skeinforge 50 at 0.35mm layers and printed with silver pla at 175C on the Behemoth. I set cool to 10 second layer minimum and used the two fans as picture on high. I am very happy with the way this turned out.
I found this on thingiverse the other day. I wanted to see how it would print on the Behemoth. The only way it can be made is on a 3d printer. It can’t be assembled or dissambled (at least without breaking it). It printed great and it was very easy to break the gears free and start rotating it. I ran it in a drill a little bit and it loosened up very nicely. I’m not sure how long they will last but I intend to use them in the smaller 1 pound spools.
I picked up a piece of 41cm x 35cm x 3mm float glass at the local glass shop. It weighs in at a hefty 1029grams. I’m printing a 300x300mm square picture frame just as a test of the large surface area. The glass does sag a bit in the center but that can be easily remedied with some supports underneath. So far it doesn’t seem to effect the print.
I think I’ll work on a system to make these print beds easier to interchange. I’d like to be able to put the smaller bed back on there when I need heat on the bed.
I’ve been working on this mirrorless DSLR sized camera gimbal for a while now. As usual this project has eaten most of my time over the last month due to my obsession with needing to get results. The high I get from a succesfully completed project makes it worth it – usually.
Today was the day I claimed my high. I wish I could say this worked without any revisions. Luckily though the revisions weren’t many or too involved. The gimbal itself only required one revision. The carbon fiber tube (12mm) that I used didn’t resist twist well enough. This led to bad oscillations on yaw and pitch. Solved with aluminium tube.
The next issue I needed to tackle was the mounting system. It needed to isolate vibration, hold without flex and be as light as possible. I ended up trying 3 mounting systems before settling on this. This final design encorporates a front to back carbon fiber tube to resist flex in pitch and G10 plates for stabilizing flex in roll.
I needed to isolate the hole gimbal from vibration from the props on the hexacopter. I chose to do this with silicone fuel tubing. I drilled holes through the G10 that fit the outer diameter of the tube. Then used 3mm screws with washers on each side to sandwich the tube between the G10. This appears to be adequate from the results of the video
Aside from the aluminium tube, assorted screws/nuts and G10 the rest of the parts are made from ABS. The parts were 3d printed. The ones requiring high strength were printed at 95% fill.
What’s up next? The addition of a dedicated stabilizing gimbal controller. Currently looking to purchase a Hoverfly Gimbal Controller.
This is what I normally use for motor mounts. It weighs about 23 grams and is made of HDPE and FR10 G4.
I designed a 3d printable motor mount and printed it out of black abs. It allows me to locate the motor about 4cm further out on the arm. The downside is it weighs about 29grams. I know that doesn’t sound like much but it adds up quickly with the need for 6 of them in a hexacopter. I haven’t decided whether I am going to use them or not.
To say that the laser alignment on my ebay laser was poorly done would be an understatement. All of the mirrors were positioned in a way that was impossible to have the beam centered in all of the mirrors. I decided to completely redo the alignment. I started at the laser tube end. In the following picture you can see the original stock mounting bracket on the left and my new one on the right (ignore the new one for now)
The problem with the stock bracket is that it uses spacers to adjust the height. Guess what? They didn’t include any extra spacers and the height was wrong. The tube was too high and sending the beam into the top 1/3rd of the mirror. So the over engineering obsessive maker in me saw this as the perfect opportunity for a new project and this was born…
Not wanting to leave well enough alone I decided that it would be nicer to add some fancy knobs for adjustment and to lock the tube in place and behold!
This design would allow me to make smooth and precise adjustments of the tube using thumb knobs with the ability to lock the tube in place! The design uses 2 zip ties to hold the tube into the craddle. The craddle is lined with some foam servo tape. I leave the backing on the side that the tube rests on so the tube can expand and contract if it so desires.
Conclusion – Overkill? Maybe. You shouldn’t expect anything less from The Xnaron Project (you have been warned).