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We have a up printer and a bfb3000, people use the up printer by choice, because it just does the job,
the bfb is still not working as well after some time messing with settings, but the price is a bit high for the up printer in my opinion.
by
johnrpm
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General
Here is a screen shot of the software so far
Working from left to right
Image process, ...is intended to allow printing shells and reducing the amount of ink on the infill
Paulo's slicer,... is a front end to his slicer, to make life easier, I may add the freesteel slicer at a later date.
Serial port,... to select the port the arduino is using.
Printer,... select the image files to print, simu
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johnrpm
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Powder Printing and Selective Laser Sintering
I worked on a EOS metal sintering machine some time ago, it had a unit that extracted nitrogen from compressed air, but
do not have any details of how it worked, the unit was small but very efficient and filled the build chamber in a short time, the
3d systems machine had a massive unit with very large tank, the EOS system was much better.
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johnrpm
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MetalicaRap
Some time ago I Spent some time working through the various aspects of building a powderbed printer, I got to the stage where I think I had solved most of the tool chain, software and hardware, then came across Fogassa's work, so I decided not to persue it, as he had done such a good job, but recently someone asked me for help building a powder printer, this has revived the old project, it would
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johnrpm
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Powder Printing and Selective Laser Sintering
Long shot here - any chance that we can agree that files useful to humans are CAD files, while files used by/useful to only computers are CAM files?
This does not compute.
by
johnrpm
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General
Have a look here diy 3d printer
by
johnrpm
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General
I think it may be worth doing the opposite to inhibition sintering, that is to say print with black ink onto the powder
and fuse with an infrared lamp, the powder is held just below fuse temperature and the lamp takes it over the edge,
the black absorbs more heat than the white powder surrounding it.
I have not tried, but it may be possible to focus the infrared into a stripe so its a bit like a
by
johnrpm
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General
Not recycling, and probably suggested before, but Its just occurred to me that the binding rope used by farmers, " not sure what polymer" could be put through a die to extrude it into a filament., other "Ropes" could be considered perhaps.
by
johnrpm
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General
Many years ago, "the first oil crisis" the company I worked for could not get polymers, so installed a recycleing plant,
lorries arrived with various plastics, this went into a cracker, which was much like the above sketches by rocket scientist,
it had blades over a metre long, "which I had to sharpen" the machine had a ladder up to a platform and a shute where the
bandsawed parts were fed in, "
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johnrpm
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General
One idea I have wanted to try for years is to spot weld small metal balls, the size of the ball in a ball point pen, feed them down a tube and pulse a current, the tube would be mounted on a reprap, it would be a bit slow to fuse one ball at a time and move to the next position, but could produce parts a bit like pneumatic silencers, the part could be dipped to infiltrate if needed, or could be u
by
johnrpm
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General
I built a test head for nylon fishing line a lot of years ago, I will dig it out and post images, its so long ago I can
not remember if it worked well or not, I think the fumes were a problem.
by
johnrpm
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General
Yes, its very good, I signed up for the newsletter and its worth a read.
by
johnrpm
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General
I did this some time ago with fuel injectors, the problem was they were not stainless steel, and rusted up internaly,
I think stainless ones are available though, but expensive.
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johnrpm
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Paste Extrusion Working Group
Hello Macrotek
To try to answer your questions,
1.. frequency with drop on demand is dependent on velocity of head travel, and for continuous stream can be as high as the bimorph will cope with, say 6khz
2.. displacement of the bimorph is small, (but I have not measured it) if thats what you mean, we have not built a multijet array yet, if you are asking what distance
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johnrpm
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Powder Printing and Selective Laser Sintering
I recently bought a second hand nokia e71, and was amazed at its capabilities, ( I am behind the times with mobile phones) It occoured to me that most people will have such devices, even in third world countries some day, if not already.
would it be possible to use them for reprap, we would still need drive boards but could a phone do the job of a computer?.
jgilmore, at the risk of upsetting p
by
johnrpm
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General
Grasshopper is a plugin for rhino that can create complex structures, its well worth a look, plugins are available
for grasshopper that connect it to arduino, so you can influence your model from sensors, or your model influence
sensors, a light sensor could distort a model of a tower for example, and in real time, it opens up a world of
interesting concepts.
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johnrpm
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3D Design tools
Not sure if its my browser (firefox) but the development index seems to stop at S, missing out lots of pages, or am I
missing something ?.
Edit, Found why, need to click next 200, could this be in a more prominent place.
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johnrpm
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Administration, Announcements, Policy
Have Blue is right, you get more "feel" that way, get yourself comfortable and calm, no rush.
by
johnrpm
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General
Maybe stating the obvious, but the fluid needs to have a certain wetability, and the powder needs not to bleed to much,
pure water has surface tension which inhibits wetting, adding surfactant would help or try vodka (Hic),
Gypsum or polyfiller may be worth a try, flour, cement.... Zcorp add various things to optomise powders
thread
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johnrpm
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Powder Printing and Selective Laser Sintering
I will give it a go, I have rhino that can do 3ds and stl, PM me, No promises though
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johnrpm
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3D Design tools
I have just noticed that we have "Reprap central", first time I have seen it, looks like makerbot to me.
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johnrpm
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General
they contain the only collection of the RepRap dev team that is "up for sale".
Are reprap developers also at bitsfrombytes, if so I did not know that.
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johnrpm
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General
How many machines have BFB sold?, each one bought by a school or college takes business away from the big boys, not to mention the material supplies and maintenance contracts.
by
johnrpm
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General
For the powder bed, I have seen 3 methods that work on commercial machines,
1. the most common is the part bin and feed bin with a roller recoater
2. part bin and roller with hopper recoater
3. part bin and rotary hopper with roller or blade recoater (like a record player with the sylus arm as the recoater)
they all work, 2 has the advantage of smaller footprint but needs the hopper topping up,
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johnrpm
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Powder Printing and Selective Laser Sintering
CNC print
I was not sure where to post this but as its to do with printheads here is a good place.
I have been working on a way to use a cnc machine to print with multiple nozzles, at present, and for some time a single nozzle printhead is probably the main focus, but in time we may be able to develop a multi nozzle head, and as my code skills are on a par with a six year old ( in fact not as
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johnrpm
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Powder Printing and Selective Laser Sintering
These may help, not sure if they give actual sizes. I built a small SLS some years ago using cylinders and pistons, if you do not need heat then waste pipe 4 inch diameter would do for testing, unless you want to go bigger.
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johnrpm
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Powder Printing and Selective Laser Sintering
I saw vapour blasters some time ago, its like bead blasting but vapour as well as air and using very fine media, the SLS parts
in the demonstration looked really smooth.
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johnrpm
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General
Yes I think you are spot on, they would like us to get the componants from them, we must buy them somewhere so thats not a problem, also the ability to create your own componants means I could make my own library of the stuff I have or tend to stick to, I have played with it a few times and I do like designspark.
I have not had time to do much with your isolation milling software, I normally us
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johnrpm
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General
Well done, the first person in our community "and the majority of other places" to SLS with your own setup, you must be putting in loads of hours and have an understanding wife, all I can say is fantastic stuff.
Hot melt glue is soooo usefull.
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johnrpm
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Powder Printing and Selective Laser Sintering