Showing posts with label child. Show all posts
Showing posts with label child. Show all posts

Monday 20 July 2009

HydraRaptor's second child

Back in March I had a visit from Marcin Jakubowski, the founder of Open Source Ecology. He was over here in Manchester presenting at a conference and asked if he could come and see HydraRaptor, as he wants to use RepRap machines on Factor e Farm. Like RepRap, his project also aims to change the world.

He asked lots of questions and made a couple of videos of my answers for his blog, which you can see here.

I volunteered to print a set of Darwin parts to help get Factor e Farm up and running with 3D printing. I was confident that I would have my Darwin running in time to churn out the parts. However, because I spent a lot of time experimenting with extruder designs in an attempt to get something more reliable, I ran out of time and had to print the parts on HydraRaptor.

Here they are, all 109 of them: -



All the parts were printed with 0.5mm filament at 16mm/s with 32mm/s moves. Most were sliced with Skeinforge set to 25% fill and larger objects have double outlines to maintain strength.

Here are some stats: -


Build time Plastic volume Quantity required Total build time Total plastic Weight Cost Percentage of total

Corner bracket @ 90%
02:44:44 29.1 cc 8 21:57:49 233.1 cc 291 g $5.83 29%
Diagonal tie bracket-chris

00:27:00 4.8 cc 20 09:00:06 96.4 cc 120 g $2.41 12%
Bed corner
01:32:06 15.5 cc 4 06:08:25 62.1 cc 78 g $1.55 8%
Z-motor-bracket-chris
01:23:12 14.6 cc 4 05:32:47 58.2 cc 73 g $1.46 7%
X motor bracket
03:56:35 37.2 cc 1 03:56:35 37.2 cc 46 g $0.93 5%
X-carriage

03:51:39 40.2 cc 1 03:51:39 40.2 cc 50 g $1.00 5%
Y housing
00:56:36 9.9 cc 3 02:49:47 29.8 cc 37 g $0.74 4%
Extruder drive block
02:30:44 26.5 cc 1 02:30:44 26.5 cc 33 g $0.66 3%
X idler bracket
02:28:06 25.4 cc 1 02:28:06 25.4 cc 32 g $0.64 3%
Y motor bracket
01:51:06 19.6 cc 1 01:51:06 19.6 cc 25 g $0.49 2%
Bed constraint
00:43:20 7.5 cc 2 01:26:39 15.1 cc 19 g $0.38 2%
Bed clamp
00:21:39 3.7 cc 4 01:26:36 14.7 cc 18 g $0.37 2%
Extruder base
01:13:19 13.1 cc 1 01:13:19 13.1 cc 16 g $0.33 2%
Z-coupler-airpax
00:14:21 2.6 cc 4 00:57:26 10.2 cc 13 g $0.26 1%
Opto bracket @ 50%
00:19:00 3.1 cc 3 00:56:59 9.4 cc 12 g $0.23 1%
X-belt-clamp
00:10:46 1.9 cc 5 00:53:50 9.5 cc 12 g $0.24 1%
Wiper-diagonal-bracket
00:43:50 7.6 cc 1 00:43:50 7.6 cc 9 g $0.19 1%
Wiper-brace
00:13:24 2.3 cc 3 00:40:11 6.9 cc 9 g $0.17 1%
X-constraint-bracket
00:38:10 6.6 cc 1 00:38:10 6.6 cc 8 g $0.17 1%
Pulley
00:12:35 2.2 cc 3 00:37:44 6.7 cc 8 g $0.17 1%
Bolt plug
00:04:36 0.8 cc 7 00:32:11 5.8 cc 7 g $0.14 1%
Tall foot
00:14:27 2.6 cc 2 00:28:54 5.3 cc 7 g $0.13 1%
Y motor coupling
00:25:02 4.5 cc 1 00:25:02 4.5 cc 6 g $0.11 1%
Z-adjuster-housing
00:24:12 4.1 cc 1 00:24:12 4.1 cc 5 g $0.10 1%
Short foot
00:11:21 2.1 cc 2 00:22:42 4.2 cc 5 g $0.10 1%
Fan base
00:22:29 4.0 cc 1 00:22:29 4.0 cc 5 g $0.10 1%
Y belt clamp
00:03:43 0.7 cc 4 00:14:50 2.6 cc 3 g $0.07 0%
Fan-leg
00:15:48 2.8 cc 1 00:15:48 2.8 cc 4 g $0.07 0%
X-motor washer
00:15:27 2.8 cc 1 00:15:27 2.8 cc 3 g $0.07 0%
Z-flag-slider
00:13:00 2.3 cc 1 00:13:00 2.3 cc 3 g $0.06 0%
Bearing 360 run
00:02:47 0.5 cc 4 00:11:09 2.0 cc 3 g $0.05 0% HDPE
Extruder PCB holder
00:09:45 1.7 cc 1 00:09:45 1.7 cc 2 g $0.04 0%
Z-opto-flag
00:08:45 1.6 cc 1 00:08:45 1.6 cc 2 g $0.04 0% Black ABS
X-carriage-bearing
00:08:39 1.1 cc 1 00:08:39 1.1 cc 1 g $0.03 0% HDPE
Y-opto-flag
00:07:43 1.4 cc 1 00:07:43 1.4 cc 2 g $0.03 0% Black ABS
Bearing 360 jam
00:02:49 0.5 cc 2 00:05:38 1.0 cc 1 g $0.03 0% Black ABS
X-opto-flag
00:04:43 0.8 cc 1 00:04:43 0.8 cc 1 g $0.02 0% Black ABS
Wiper-lever
00:04:26 0.7 cc 1 00:04:26 0.7 cc 1 g $0.02 0%
Z-flag-clamp
00:03:20 0.6 cc 1 00:03:20 0.6 cc 1 g $0.01 0%
Circlip
00:01:26 0.3 cc 2 00:02:53 0.5 cc 1 g $0.01 0%
Bearing 180-x
00:02:38 0.5 cc 1 00:02:38 0.5 cc 1 g $0.01 0% HDPE
Bearing 180-z
00:02:03 0.4 cc 1 00:02:03 0.4 cc 0 g $0.01 0% ABS




109 74:28:04 778 cc
973 g
$19.47 100.00%

The times and weights are calculated, and don't include the raft time, which is significant, or the time waiting for temperature changes and raft cooling. I weighed the parts on kitchen scales and they came out at 931g, so pretty close to the calculation. The cost shown is on the basis of ABS at $20 / Kg.

I save all the rafts for the day when we get recycling working. I weighed them in at ~ 200g, that is about 20% wastage and will bring the actual printing time up to about 100 hours.



I also wasted 150g in failed prints, for silly reasons, more on that later. It gives a measure of the reliability I am achieving at the moment, i.e. 8 parts failed out of 117 prints so 93% success rate. Of course the bigger the part is, the more chance something will go wrong, so by weight and time it is much worse .



I used plain ABS for most of the parts because it seems to bond better than coloured. I used black for the opto tabs. No guarantee that they will be opaque to IR, but I think black ABS usually is. The green parts are just ones I had left over from experiments.

I made some of the bearings in HDPE as that should be a better bearing material than ABS, lower friction and longer lasting. The black ones are "jam" bearings so I left them in ABS as they want maximum friction.



Some of the parts are my own design. Most significant are the z-axis parts described in the previous post. Here is a list of the other design tweaks, with links to the article describing them:- simplified diagonal tie brackets, X-motor washer, x-carriage bearing and the feet.

Some parts I had never printed before. The Pinch wheel extruder: -



The nozzle wiper assembly has appeared in the latest Darwin release but I can't find any assembly instructions. I leave it as a puzzle for Edward Miller, the guy who is actually going to build this machine.



Similarly the new adjustable z-opto flag assembly: -



I aimed to print these parts over the course of a week, three batches a day, but the machine had other plans and it actually took me two weeks. I will give more details tomorrow.