Tuesday, December 28, 2010

copyright and patent

It was recently blogged about US law and 3d printing, after reading the entire paper I had two questions, both of which i emailed the writer, hopefully I will get a response soon. Those questions were about copyright vs patent in the law. specifically if someone posted a design somewhere i.e.thingiverse and then later a company filed for a patent for the same device, and received the patent, would it supersede the copyright or would the posting of the device automatically invalidate the patent due to not being unique or original.

After pondering this for a bit something else came to me, the copyright's that are put on things in thingiverse are (other than as a record) worthless, they have no real meaning since copyright cannot and should not be applied to physical objects, and we as makers do NOT want to change that.
really.
think about what it would do. right now a patent has a very short shelf life of about 12 years (i believe though for some reason 7 seems to come to mind) but a copyright is life plus 90 years or so!!!!

companies have been trying to get patent length extended for years and they have also tried to apply copyright law to patentable objects, so far thankfully none of these have panned out for them.

now, this doesn't mean that i think people should stop posting things or putting a gpl license on them, on the contrary, if i understand patent law then we need to post MORE things, the more we can prove non patentable the better. But also note. once something is posted it cant be patented ever, even by the original poster.
years ago back when i was a kid my uncle made a gold panning device, he made the mistake of selling a few of them before he patented it. results: patent rejected, item already exists for sale.

now, I have no references to quote and IANAL and neither do i play one on TV so don't take any of this as legal advice. not that any of it was actually intended as advice, just as a HMM moment.

Tuesday, October 26, 2010

mk5 and mendel

Well, ive been working for the last month or so to get dual mk5 heater cores printing on my mendel with very limited success. My biggest issues are excessive loading of the filament through my bowden cable. I can get pla to run through it at REALY low speeds but if I try to extrude over about 10mm/s it jams and strips the filament in my wades extruder. Ive been wondering if the hobbed bolt i made was the cause so I ordered some from ebay about a month ago but have yet to recieve them.

One of the issues I have with the pla is probably filament swelling leading to excessive backpressure but so far I havent found a solution to that. The 1/8" stainless pipes I tried initialy as filament guides seemed to transfer heat too far up their length causing real bad back pressure and when I tried to shorten one of them I made it too short and the ptfe tubing swelled and deformed between it and the upper filament guide section. I currenty am trying a stock makerbot barrel and nozzel assembly and with it I can get the 10mm/s or so feed rate with some reliability though i had to add two heat sinks instead of the standard one. I beleve this is at least partly because the mendel carriage encloses and retains the heat better than a standard makerbot open air design.

Thursday, September 23, 2010

x axis mods

I have been working on getting my mendel printing more reliably and have changed the orientation of the x axis motor. The main design puts way too much drag on the axis to print. or at least on mine. Also working on installing makerbot mk5 hot ends so have redesigned the print carriage so the mk5 head can fit between the rods. right now im printing it on my makerbot. Im also considering a mod of the x-z connections to widen the spacing of the rods, right now im concerned that the heat from the extruder may cause issues with the carraige regardless of the new design.

Thursday, August 26, 2010

hot end experiments

I have been working on some new hot ends for a while, I purchased several kits from makergear of the Noophead style and have one of them installed in my makerbot right now. then wouldnt you know it but makerbot releases their mk5 extruder and completly changes the course of my expiriments. after looking at their design (i have one hot end on the way and parts for 3 more) I started working on fabbing some equivelents for my mendel.

I will probably post pictures of each test one of these days but the one that im fealing the most confidant about was pretty simple. take a section of 1/8" schedual 40 stainless pipe, turn down the end to 3/8" and thread it 3/8-24. then using one of the aluminum blocks from the makergear kits I drilled it out with a Q bit and tapped it to 3/8-24.

my first test used a single resistor but it could only get to 130C so i have fabricated a new one with two resistors. I have a fealing that im going to have to drive power to each seperatly with my current set up since its a gen2 pwm board so i doubt it can handle the current draw of both resistors in paralel. I may try just applying 12v directly to one and triggering the other with software.

I will post more later, hopefuly with pictures.

Friday, August 20, 2010

terminator

Ive been working on some prints and watching netflix for the last couple weeks and got into watching the terminator tv series. I have to say Ive always loved the franchise but it has always caused me to both laugh and scream.
When terminator first came out it was showing the fears of society in a very real way to the best of hollywoods abuility to show, but looking back at it the whole concept is ludicris. If man were to somehow create a truly artificial intelegence there wouldnt be a fight. No war. No battle. Mankind would either cese to exist or just become a slave meatpuppet.

The good thing is, truly artificial intelegence is a long way off, not that i believe that we will not achieve intelegence in silicon soon, just not artificial intelegence.

Atomicaly precice manufacturing will soon become a reality. While i dont have much hope in it occuring in reprap first I know that once it occurse reprap will achieve it in short order. With that leap there will be a whole new dimension of technology occuring almost simultaneusly.

There are so many things I could write about but going back to the terminator stories, obviously the machines had developed the technology, at least in the form of Utility metal or as its sometimes called claytronics. The truth of this type of technology is, a war fought with it and one side possessing it only isnt a war. One of my greatest fears is nanotech being in the hands of the few or the one. If everyone has it, its just a tool. If one person has it its a weapon.

Please forgive the typeo's I dont have a spell checker on this computer so will probably edit this again when im on a different one. Also please forgive the rant. Most of you who would be reading this already know what im saying so im just preaching to the choir, but sometimes you just have to rant :)

Tuesday, August 10, 2010

steamrap

The other day i was on irc #reprap and somehow we got onto the subject of steampunk. there were a bunch of ideas thrown around about punking a reprap but it got me thinking about doing a real steampunk reprap.

My design idea's are still in the rudimentary stage but here are the thoughts on it.
using two steam pistons at 90 deg from each other on a connected cam you can make a steam steper with 4 steps per revolution, connecting this to a hypocycloidal gearbox
http://www.thingiverse.com/thing:3736 with a 100:1 gear ratio makes it a 400 step per revolution steam stepper. by printing the parts in pla and doing lost pla casting of bronze or copper parts I believe i could print the entire printer to include the guide rods or a equivelent design. essentialy printing all the parts for the printer. It would require some post printing/casting machining but i dont believe it would be eccessive.

if i actualy get it built I will probably be testing it with reletivly standard electronics at first but the end desire is to have it print by being controled from either a player piano style reel or with punched or raised copper disks similar to a music box.

of course so far this is just in concept phase but i figured i would throw the idea out there and see if anyone else thought this idea was just too cool to pass up trying.

moved

well, im now moved onto the boat, and actualy have been for the last month but getting organized in the new cramped environment has kept me from doing much printing. I did print out a new x axis carriage assembly to replace the one on my mendel, its a bit warped and I feal its causing a lot of the stiffness in my axis. I havent installed it yet and im probably going to print out some new footed frame vertexes before i do the disassembly and reassembly.

I also just ordered a batch of bitg head nozzels and noophead style heaters from makergear and another mega board from makerbot, my last one im having some issues with installing forth onto and all of the blog posts ive seen of my symptoms point to a board failure of some kind. I plan on downloading the new mega's kernel and trying to install it on the forth one to see if i can unbrick it, if so then ill try installing the forth kernel on the new mega and see what happens. If i cant unbrick the one well, at least ill have a save of the mega firmware to resort back to.

Im also seeing a bit of rust developing on my bots from the salt air so i may have to try installing zinc's to them first and if that doesnt help replacing all the steel parts with stainless. that could get a bit on the spendy side but i guess that is just a price you pay for the mobility of a boat :)

Tuesday, June 8, 2010

moving to the boat.

well, im starting my move to the boat so have to get some of my junk into storage. I have a bunch of pneumatic cylinders and vfd's im holding on to for future projects.

gonna try to show the pics here, we shall see :)
http://www.flickr.com/photos/50190050@N03/4682632675/
http://www.flickr.com/photos/50190050@N03/4683266900/
http://www.flickr.com/photos/50190050@N03/4683264546/

hmm, that didn't inbed the pictures but you can look at the stream and see what im talking about.

in the junk is a bunch of hitachi serial controler interfaces. they support rs485 and one of these days i may get around to interfacing them with mendel. though i might wait till i have the forth firmware running which would make it completly autonomous printing.

still having issues with my x axis. if you look at the failed print of the pink panther woman you can see a distinct sine wave traveling up her legs. I really wish i knew where it was coming from.
the period of it is so great it has me realy flabbergasted.

I did order a new mega board so i can start working on the forth port firmware. I have high hopes that this project will be worthwhile. Forth is a real good fit for reprap.

Sunday, May 16, 2010

mendel 109 printing

After several diferent firmware attempts I retried joaz's mega fork and got success.
Ive been working on tuning since i got the first shotglass print. The reprap firmware shotglass printed fully though it was a very poor quality print. after a lot of skeinforge massaging and quite a bit of assistance from tonok on irc i was able to get a reasonably high quality shot glass printed. The second skeinforge print was a wades extruder which came out realy well (after numerous aborted attempts).

I found that my x and z steps per mm settings were off and made adjustments ( i hope in the right direction) but havent had a chance to get a full print since.

note for my changes i got 106mm out of 109 for full lenght and 25mm instead of 28mm for height.

for z (which was most pronounced) i went from 400 steps to 448. dont remember what i did for x off the top of my head but i went the same direction.

Friday, May 7, 2010

working on first print

everything is assembled and functioning to a point,but having issues with extrusion and posibly positional accuracy.

first off. ive been trying to use the nema 23 bowden extrusion but all i get are striped filaments, it appears that the motor heats up too much and softens the plastic. so I tried to use wades extruder but only had a makerbot stepper to drive it which was too weak to push noodle through at any reasonable rate. After talking to some people on irc i picked up some lin motors at a reasonable price and promptly pushed my barrel right out of the ptfe insulator :( .

I may construct one of nopheads pipe covered barrels next though i may just put in my dual block extruder barrel and try it first using a cable and wades.


BUT....

I have another issue i saw in the little bit of printing i got before failure. My X/Y stepper motion is wrong. for some reason step direction is not being passed to my drivers before the step pulses. so when traveling in one direction the steppers do some of their steps forward and the rest in reverse so my print looks completely wonky. it really becomes noticeable on short segments.
Im using the Ardrino MEGA board, pololu stepper drivers and I believe joaz's mega port.
Ive tried david buzz's and mycoyn's but neither of them appeared functional when i tried them.
A couple of people suggested to just use the standard fork and do my own modifications but i have been hoping to not have to redo work that has already been done.
Has anyone else ever seen this behavior and have any suggestions?

Saturday, April 10, 2010

firmware

worked on my mendel over the last several days, and installed different firmware. using http://github.com/mccoyn/reprap-firmware-fork i believe. with some minor modifications for the pin outs im using. I am still having some issues with movement but the motors are stepping now at least for the most part :)
The thermister table appears to be off but that is easily fixed. not sure yet if there is anything else missing from that firmware branch but at least it communicates with the reprap software without locking up.

Sunday, March 28, 2010

mega and pololu

well, i've gotten the pololu boards soldered in and I installed buzz's mega firmware with some modifications. but.... well, every time I try to move one of the steppers it appears to lock up the board. I can get the heaters to work but havent been able to figure what the issue is yet.

There shouldnt be any reason for the board to lock up unless there is some internal conflict.

wait, i have a idea about the endstops causing this lock up. ill write more later

Monday, March 22, 2010

laser sinstering

I have been working on starting up a local hackerspace and have a computer and recycling center that is supporting the project. while i was there the other day we were talking over a dumpster full of old toner cartridges and they were mentioning that disposing of the toner its self was a problem. Then as Im looking another thought came to me, the toner is essentially powdered plastic, so why wouldn't it work as a laser sinstered powder printer.
Then today arrives in my mailbox another instructible and in it was how to make a low power laser cutter. Im thinking mix the two idea's together and you have a laser sintered powder printer.

I will post more as the project develops.

Sunday, March 21, 2010

extruder issues

well, after getting the firmware installed and getting the configuration functioning ive been working on the extruder. I keep having problems getting all of my set ups functioning. All of the bowden systems ive set up have so far failed. not sure why yet but the amount of pressure required keeps pushing the bowden cable out of the connections. Some of the problem may be with the peek insulators developing to much friction on the filiment. I have tried it with pla and abs, when i use the pla it starts puddling at the top of the insulator and the filiment begins deforming from the heat. Abs just seems to jam. Eventualy i will figure out the issue but right now i just want functionality.
I have tried using one of the last of my ptfe insulators directly coupled to my original mendel extruder. Unfortunately i havent been able to fix it into the extruder mount solidly. I tried using screws but those ripped the plastic, and ive tried epoxy but that didnt develop a effective bond.

I am still working on solutions

Thursday, March 18, 2010

reprap firmware and direct to stepper

Well, after seeing some of the comments to my last post I decided to try the reprap firmware again and connect the stepper driver directly to the mb using the sda/scl pins directly. The firmware appears to have uploaded to both boards so My hopes are up right now.

Another new thought came to me last night as i was working on it. I happend to look over at one of my old extruder heater expiriments that got me thinking along another line. I had tried using a stainless insulator and was using a Nordson glue gun tip in it .016 in oriface. As i looked at it all of a sudden the thought of a water jet cutting tip flashed in my head so today i threw together a pressure washer coupler, a bolt with a 1/8" hole drilled through the center and one of these tips. I was of course hoping to get enough pressure to potentialy cut through something with it but my first tries have not been promising though i have to admit we have the pressure turned way down right now due to several people cutting themselves using just regular nozzels (i think its between 900-1200psi right now) and since they are using it for production cleaning i dont have a oportunity to turn it up and see what it might do.
I also was looking at some info online and it appears the lowest pressure a commercial waterjet cutter runs at is about 20,000psi which is way higher than I want to try rigging together right now. Im hoping that i might be able to cut thin aluminum sheeting at as little as 3000# since ive seen hydraulic lines pop holes in themselves and cut through peices of sheetmetal before.

I will keep posting any info I come up with.

Tuesday, March 16, 2010

extruder board firmware

well, Ive desoldered both h-bridges on one of the extruder boards and soldered in wires to D5-8
and connected those to a old v1.2 stepper board hooked up to the lin stepper.

It appears to work very well though the firmware doesnt support this configuration in any way. I tried rewriting the firmware to use the outputs as enable/step/direction but had no success with it so far. I did get it stepping by just connecting the direction signal to step but then I have no way to control direction. (note: this is with makerbot firmware)

I will keep working on it though.

oh as a aditional note, when i ordered my 624 bearings i didnt order enough so im short 1 or 2 and im waiting for more to arrive before i get too excited about running mendel 109-01's axies

Sunday, March 14, 2010

lin nema 17

well, I hooked up the new nema 17 stepper i got from lin to the extruder board.....
nother blown board.....

Im having some difficulty understanding why they would blow the h-bridges like this. They are supposed to be rated at 2 amps and this stepper is not supposed to draw more than that but obviously it does. My next step is going to be two fold. Im going to desolder the h's and rewire the board to connect to a regular stepper board, then reprogram the firmware to drive the stepper that way.

The other half is to assemble the pololu boards i have into something resembling what adrian posted the other day. I already downloaded the mega code into my new mega board though i didnt try personalizing it to my hardware yet, just a test download realy.

also planning on cutting my aluminum build bed today. I have a lexan sheet in the mendel right now but that was mostly just for testing and calibration.

Wednesday, March 10, 2010

stepper extruder

well, i recieved two makerbot nema 23 stepper motors two days ago and two nema 17's from lin yesterday so im back to working on my bowden mount's.

Big Notice for anyone attempting to connect the makerbot motor directly to the extruder board.....DONT.

I ran it for about 5 minutes without any filament in it and all looked good so i began feeding the filament through and after about 220mm at 10 steps/?units everything stopped. I no longer get anything out of the h bridge's so im assuming i burned them out. I Then (a little late) looked at the specs and saw how much current those motors pull and realized how bad of a idea it had been.

I have a bunch of the pololu boards coming so i plan on trying the new electronics adrian posted and see how i like them but for now im just down another extruder board.

The other thing that sucks is with all the printing ive been doing both of my functional makerbot gearmotors are wore out and they are out of stock on them again, so im kind of at a printing standstill right now.

I have a mendel extruder printed already but the drive hub I made that would fit it i had to modify for the 23 motor shaft which is now not working and my geared mendel extruder i printed now has a issue with the small gear not fitting tight enough on the lin shaft to drive it there either.

Sunday, March 7, 2010

axies aligned but...

well, worked on mendel last night and got the axies freed up but... now my z axis sprocket has wallowed out and will not stay tight on my stepper. gonna have to either print a new one or glue it to the shaft. oh well.

something that Im also working on right now is a positive displacement pump extruder. Its going to take a bit of machining but i have high hopes about getting this functional. For those that dont know what a pdp is its basicly a gear pump. take two gears and mesh them together inside a confined space with a inlet at one side of the pair and outlet at the other -->8-->. its how a oil pump in your car works, the oil or in this place plastic is moved around the outside with the gears and kept from returning to the inlet side by the meshing of the gears. Ill keep everyone posted on actual progress and when i have pictures ill post them.

Saturday, March 6, 2010

mendel built

well, i have all my mendel peices printed and assembled now, all the electronics on it (sort of) and have been moving the axies and even tried a first print. unfortunately i have two different issues.

First to the electronics, I only have 2 functional gen 2 stepper boards and i have 2 1.2 stepper boards. I have 1 each dead 2.3 and 1.2 boards so it makes it hard to have a single firmware that supports both. right now im back to using a proto board and a arduino mini as a signal conditioner on the 1.2 to invert the enable line.
This just makes it difficult to clean up the electronics and mount it permenantly on the frame. Im also probably going to have to mount the steppers different from the instructions since my ribon cables are all too short to reach from the motherboard all the way to under the y build table.

now to the other issue.

all three axies are too stiff and are causing my steppers to skip steps in at least one direction. Im probably going to have to dissasemble it and work on improving the alignment.

Saturday, February 27, 2010

mendel

well, just made this blog and figured i would post that im just a few peices short of having my mendel printed and assembled. Havent decided yet if im going to put the stepper extruder into it right off the bat or run one of my makerbot print heads into it for set up and calibration.

We shall see :)