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We are looking into it where I work...not at all cheap. And that is jsut the printer. The scanning option basically double the price. What we've been looking at is laying down a layer at time of an extruded ABS material.

Can we pick apart the video though? The printed part does not match the original wrench. I do not think that the scanning process would be done handheld to get 40 micron accuracy that they claim.
 

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Super Modulator
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Large amount of misrepresentation.

The major thing is that the scanner has no way to know which parts are moveable, and where to place to air gaps.

Also, no way it could "see" all of the thumbscrew part (which is radically different from the real wrench, and the one they printed).

Obviously someone has to take the 3d scan and "break apart" the moving pieces and "fill in" the hidden areas.

But, once you create the proper 3d model, it does work, although it's expensive as already stated, not just the hardware, but the materials.

For one-off copies of a solid, it's great at making a copy, but no one is going to make a locomotive from it for any cost even approaching what we are paying now.

In the future, it's not clear this will get a lot cheaper, the hardware tolerances to make this kind of printer kind of prohibit it being cheap.

Regards, Greg
 

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I talked to Bob Hartford at Hartford Products the other day about some castings, and he mentioned that he has a local 3-D printer shop available, and they can produce masters from a 3-D CAD image. He has 2 produced and uses one to make a mould for the brass or whitemetal casting.

Seems like a pretty neat technology.
 

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My son has been selling 3D printers for 5 years or more. He also owned a company once that used these machines to print prototype parts (mostly for the auto industry....ever wonder how they engineered the plastic parts of a dash board or the ducting below?). The device is VERY cost effective to make thin plastic parts (think ducting) as the amount of plastic used dramatically effects the end cost. My son set up his company so that engineers could email CAD drawings to his company which were converted into machine files and then printed. He guaranteed 24 hour turnaround on the parts...printing them overnight and then FEDEXing them so that the engineers had the "new" part the day after they sent the CAD file.


He also printed a LOT of cell phone and PDA prototypes...but those required hand work after printing because the finish of the final part out of the machine is not smooth like you'd get from injection molding. They're good enough for prototyping for engineers, but for marketing analysis, they required buffing or hand sanding under water with 600 grit or more sandpaper. The machines could easily print a whole car...but you'd need to apply the 20' rule. They definitely would not pass a rivet counters examination.


Greg's right...there's a lot of cleanup of the CAD files to make the machines work right in producing the desired part or assembly. Not explained in the video is that the printers that use ABS plastic also use a second, dissolvable plastic. The dissovable plastic is used to support the 3D structure as it is printed and is "washed" away after the print job is done. This allows the part to retained fixed dimensions as the plastic is piled on layer by layer. This means that you need to consider structural rigidity and design in supporting structures as you do you CAD work.


The scanning technology does do a lot to make making replacement parts easier. A lot of time is saved but all of the scan jobs require significant reengineering...like for that adjuster in the movie, But that's pretty simple if it's just a part that needs to be revolved....or cuts that go through where parts slide.


The scanner saves a LOT of time if you're trying to modify an existing machine. I recall once when he took the scanner over to BAE's factory in San Jose that made Bradley armored personnel carriers/tanks. They wanted to fit something new INTO the tank...so my son put the reference stickers on the tank and scanned it. The scanner output was used to map the voids in selected areas into which engineers could install new assemblies. The voids were then printed so that a plastic shell was created into which new assemblies could be inserted and tested for maintenance access. He printed the "new assemblies" too. BAE saved time by only printing the shell voids that they intended to modify.


For GRRing, these machines have a lot of potential. For sure, they'll print building easily...but expensively. I'm looking at them to print just the frontage of a building as that is where most of the detail would be. The frontage would include all the details...grain of the wood, windows, mullions, doors, door knobs, walkways, lamps, signs, etc. To keep cost down, I need to really print a very thin layer that is laminated onto a stronger structure. If you know how to use 3D CAD, you should be able to make a building front pretty fast. How much it costs to have made will depend a great deal on how good a CAD file you've created. If it requires a lot of "fixing", the costs will kill you...but given the cost of detail parts these days, a frontage print could be cost effective.


Lastly, if you're into limited mass production of parts from resin, you can use the printer to make a mold directly OR a master for a mold you make. This is particularly effective for small parts. My son does a lot of this kind of work now as he runs the prototyping division of a plastics company...but those molds are intended for injection molding machines which require the efforts of a tool maker/mold maker to clean up. As I said, the ultimate finish achievable is NOT completely smooth...so if the end part is to be smooth, you need to sand or blast a bit.
 

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A Steamed Elder
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"Greg's right...there's a lot of cleanup of the CAD files to make the machines work right in producing the desired part or assembly."

The CAD files, more precisely the solid model files need to be "water-tight" to work as desired. NO FLAWS in the solid model. This is an "inside baseball" term that most CAD users will understand.
 

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This company sells N and Z (my other scale) buildings and vehicles http://www.makemymodel.c...trong>




I think this is the stuff that is cured by UV, and of course it's not the structural stuff as shown in the video.

The small size of the buildings and vehicles makes the rough surface a bit harder to see.

Regards, Greg
 

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Bob Hartfords C&S/RGS 1:20.3 bettendorf trucks were done completly from 3d solid models and were drawn in Solidworks from the Prototype drawings for the most part. parts were only thicked to meet the minimum wall thickness stds of the printer. expensive process, but you can take some materials direct to rubber molds and then make all you want. I worked with Bob on this and had a bunch of my own parts done this way. iT beets the **** out of making brass masters to scale.

Al P.
 

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Check this 3D printer out, it’s relatively cheap. I have a Thing-O-Matic on order, been watching this one evolve the GEN 4 interface controller board and Mark 6 Extruder is currently offered with the kit..

http://www.youtube.com/results?search_query=makerbot+3d+printer&aq=f

Michael
 

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A while back I watched a series in Discovery Channel (I believe) called, "The Next 50 Years." One episode was on medicine. The forecast was that they will use similar technology to "print" you a new heart, lung, kidney... whatever, based upon a scan of your own organ and using your own cells. According to the show (and this was a few years back), they can already "print" living beating heart cells on a medium. Amazing!!!
 

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Discussion Starter #13
They are doing this now a news story showed growing a windpipe/partial throat, and was implanted, and the patient has experienced a new life over what he had before! Regal
 

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They are doing this now a news story showed growing a windpipe/partial throat, and was implantedI believe that's something different. I've seen where they grow cartilage parts such as ear structures on a mouse's back (the windpipe is partially made of cartilage). That's not the same thing as creating a complete living organ via a 3D printer though.
 

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I don't know if it was the same person you are thinking of Regal, but I did see a show about a woman in Spain who had her windpipe replaced with a new one. In the show they took a windpipe from a cadaver and then dissolved the original cells out of it leaving behind the protein superstructure. Then the woman's own cells were fed into the empty superstructure where they grew into the spaces left by the old cells. Then it was transplanted into her with no possibility of rejection because the windpipe has her own cells in it. Very cool stuff. They also talked about building the protein superstructures using 3D printers, but they are not quite able to get the details that are needed yet.
 

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Posted By Pete Thornton on 11 Jul 2011 12:31 PM
I talked to Bob Hartford at Hartford Products the other day about some castings, and he mentioned that he has a local 3-D printer shop available, and they can produce masters from a 3-D CAD image. He has 2 produced and uses one to make a mould for the brass or whitemetal casting.

Seems like a pretty neat technology.
How much does this service run Pete?
 

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Been keeping an interested eye on the developments on the 3-D printer field
; giving some thought to maybe attempting one of the kits.
At this stage, the technology's about where owning a home computer was @ 1978; & at the other end of the room from my modern PC (64-bit AMD 2.2 GHz dual-core CPU, 1.5 TB RAID 0 storage, Win 7 Pro 64 bit), sits my first computer
- a SouthWest Technical Products Corp 6800 kit, @ 1978 vintage.
(Mototola M6800 8-bit CPU @ 1 MHz., 16K ram (originally only 4K!
), NO disk drive (300 baud audio cassette interface - even an 8" floppy drive cost @ $600
back then!). I've been an "early adopter"
of new technologies in the past - oh, almost forgot the 20-pound VHS separate camera / recorder rig sitting in a cabinet behind me!


Tom
 

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in responce to how much this sevice costs, there are a lot of factors involved. do you have a 3d model in one of the nessasary formats to convert? if not you will have to spend money to have some one create one. depending on the complexity of the part and the completeness of the documentation from which to create the model you are looking at $35-50 an hour to have it done profesionally. most simple parts with good documentation will be done in an hour or so. the model is then scaled to the apropriate scale 1:20.3,1:29 etc and then it needs to be examined for wall thickness. right now the normal min wall is about .015 inch. only then can the file be put in the *.stl format to send to the 3d printer. this cost is affected by the amount of resin by volume, the number of copies to be made, how many other parts you are doing at the same time. they typically run only your parts in a batch so the cost is prorated by the machines time to create your part. making multiple copies of the same part and running all your parts at the same time greatly reduces the per part cost. another consideration at the design phase is how your part can be best placed in the rubber mold. keep in mind the the rubber mold process may consume your 3d part from the standpoint that it is often broken getting it out of the mold. the mold however can then be used to produce the final parts you need.

as you see there are many factors involved and can only be priced on an individual basis based on the parts geomety.

Hope this helps

Al P.
 
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