Printing Parts

[Seanz0rz]

Yes, you read that correctly. The ability to print out parts. These may be parts such as clips, brackets, holders, replacement parts, and even major components in complex mechanisms.

So now that I've probably confused you even more, take a look at these links, to fill in some of the areas I won't cover:

OhmEye's Introduction and Orientation for 3D Printing with the Reprap Prusa Mendel

http://reprap.org/wiki/Main_Page

This machine is the basis of my Senior Project at Cal Poly Pomona, for my BS in Engineering Technology. That's why it's important to me.

Why is it important to you? - Because you can quickly and cheaply make prototype parts or working assemblies of things you've always wanted but no one ever made.

Here is my machine:
http://i955.photobucket.com/albums/ae38/hamiltonfabrication/IMG_3570.jpg

Total cost for all consumed materials is right around $500 dollars. Not the most inexpensive piece of kit, but well within the reach of the average hobbyist. I have about $650 into mine, because of minimum order amounts, and ordering some unnecessary parts.

As an extension to my primer on plastics, here is how this machine uses plastic filament to create complex three dimensional objects.

Plastic, most commonly ABS (previously discussed in the link above), or PLA (a newer plastic derived from bio-mass, very "green") is fed into the machine as a filament. This is most similar to weed trimmer line; although that is most often made of nylon, and unusable in this situation. This filament is fed through a mechanism that very precisely controls the amount fed. it then enters a hot end where it is melted at temperatures above 200 degrees C, or over 400 degrees F. It is then extruded through a small nozzle (Fractions of a millimeter) and is deposited as a thing line on the bed. a 3 axis machine controls precisely where this filament is deposited. Perimeters are deposited first, then filled in. this process is repeated for each layer of the part, until the top is reached.

So what can you make with this? Pretty much anything you want, as long as the plastic will stand up to whatever abuse you plan on putting it through. Obviously creating a new set of valves or a camshaft for your engine is not a possibility, nor is suspension components. However, things like clips to hold fuel and brake lines, wires, etc. brackets to mount GPS units, radios, etc. The options are limited by imagination, print area, and material performance.

So far I have designed a few household fix items, and a couple of brackets to mount my electronics on my printer

http://i955.photobucket.com/albums/ae38/hamiltonfabrication/IMG_3569.jpg

and this:

http://i955.photobucket.com/albums/ae38/hamiltonfabrication/UYLOGOkeychainsmall.jpg
http://i955.photobucket.com/albums/ae38/hamiltonfabrication/UYLOGOkeychain.jpg

Sadly, I lost the 3d files for that, but as soon as I can redraw them, I will print it. After that, we’ll see about distributing them… but that’s a topic for another thread.

Obviously I didn’t even scratch the surface of this machine and this technique of making things from plastic. The box at the bottom is for you to ask questions, so please do!

[Obi..]

I still think trying out some R/C Car parts would be cool. You could make custom a-arms, etc for the old Tamiya stuff that's no longer around.

How about some body's, like maybe a pickup or 4Runner, or would it need to be in pieces like a model so the roof could be shaped? How much finishing work does the plastic require to make it cleaner in appearance?

[troyboy162]

thats really awesome! what are you going to make in the future?

[Crinale]

These things are awesome! and to see that you can make one for ~$500 is incredible. Considering the ones my community college has (they are the cheap ones) are about $25k a piece, and the ones at Cal Poly SLO (which i believe are the same as the ones at Pomona) are about $40k each.

Shane - just some light sanding should clean up the appearance. Sean may not have his fully calibrated yet either, not sure.

[Seanz0rz]

for things like RC bodies, it would best be done in sections. my build area is approximately 200x200x100mm, or very roughly 8x8x4 inches. large overhangs are difficult but doable.

most of those parts are better made with vacuum form molding, since that produces very thin and light shells. the area where this gets real interesting is suspension parts, because you can print one, try it out, find you need a longer arm or to put the wheel center back a bit, and can print a new one in a few minutes. if you break one, just print another!

surface finish is always going to be grainy, its the nature of the process. even on this part, produced on one of the big, commercial FDM (filament deposition manufacturing) printers, you can detect each layer and how it was laid down,
http://i955.photobucket.com/albums/ae38/hamiltonfabrication/foundry%20project/IMAG0064.jpg

depending on the plastic, you can treat it with chemicals to smooth it out. if you print in ABS, you can use acetone (a solvent, link in first post for more info) to smooth it all down. otherwise, with PLA, you can use sand paper. i print with PLA because i can print it with less heat which means less warping.

my machine is not "fully calibrated" however its producing very good, usable prints. holes usually need to be drilled out to the correct size if they are to fit on something with an exact diameter. i am still dialing in my settings, and alot of prints require settings different from others. there is a pretty big learning curve for the software. but its getting better, just in the couple of months ive been in the community, it's improved so much.

my next parts? when i get my plastic order later this week, ill print a webcam mount of my own design, a spool for my plastic, and some other useful bits for my printer. after that, a few gopro mounts, a mount for my phone in the truck, and alot of house hold items.

www.thingiverse.com (http://www.thingiverse.com) has cool stuff all the time, so im sure i will print a bunch of junk i dont need just to play with the printer.

[Obi..]

LOL.. Mmmmmaaaarrrriiiiooooo??
http://www.thingiverse.com/thing:10526

[Seanz0rz]

yep, some cool stuff on there.

im in the process of designing a webcam mount, and when i print i usually stream here: RepRap - Seanz0rz (http://www.ustream.tv/channel/reprap---seanz0rz#)

its not streaming right now, but it will be at some point in the next few days, ill try to post up when i am streaming.

[RobG]

That's Cool, I found the raprap about a year ago and am thinking of doing one as a pet project at work.

Thanks for postings this, I might be hitting you up for some help if I ever get around to starting one.

[Seanz0rz]

yep, i offer all the help i can. if you need a set of printed parts, let me know and ill see if i can print up a set for you.

[Crinale]

How strong of plastic are the parts that you make? like how much stress can they handle without breaking?

[mastacox]

Pretty cool stuff, my work has a couple different kinds of these machines. I would be interested in building my own one of these, but I think I'm spoiled by what I see and do at work... The $250,000 laser sintering machine is just awesome!

..."FDM" usually means "Fused Deposition Modeling" by the way :P

[Obi..]

:P What about KMFDM? ;) J/K..Stop mentioning the sintering machines, I miss that stuff, they're so fun to use and we made some pretty sweet snowboard bases with them.

[Seanz0rz]

..."FDM" usually means "Fused Deposition Modeling" by the way :P


lol my bad. thats what i get for staring at filament all day long...

as for strength, it depends largely on how the part is printed. what is the infill ratio (infill of parts is usually quite a bit less than the perimeter), how hot was the part printed (did each layer stick well to the one before it), which direction was it printed in, etc, etc, etc. tons of variables.

so far i broke one part i printed. it was still hot and had stuck to the bed more than it should have. when i went to pry it off i snapped it.

tensile strength for PLA should be around 15ksi, less than half the range for aluminum i believe. you would have to take into account the less than 100% density of most printed objects (you could certainly print one 100% dense, but it would be expensive and time consuming)

PLA is harder than ABS. PLA is much more likely to hold its shape until failure where as ABS will bend until it fails (that area that turns white when you bend something to its breaking point, much like bending a soft cookie, it will deform until it falls apart) each material has its uses. i print with pla because i dont need a heated bed to reduce warping, and because of the lack of toxic fumes.

[some_odd_girl]

Awesome! I've seen these things on tv, pretty sweet that you've made one!!

[Seanz0rz]

http://www.thingiverse.com/thing:10219

im printing that RIGHT NOW!!!! come watch... http://www.ustream.tv/channel/reprap---seanz0rz#

[mastacox]

lol my bad. thats what i get for staring at filament all day long...

Well, I was technically being a PITA... Fused Deposition Modeling is a trademark of Stratasys. Reprap calls it "Fused Filament Fabrication" or other similar names to avoid copyright infringement. :roll:

On another note, another cool design is the MakerBot:
http://store.makerbot.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/t/h/thing-o-matic_product_800.jpg

They're significantly more expensive (around $1000-1200, unless you find a used one), but the print quality is impressive for the price. I could totally see printing useful-around-the-home-or-auto parts using your machine or this one.

It's only a matter of time until Toys-R-Us goes 100% on-line and you print the toys you buy right in your home office!

[Obi..]

Question here, can you "re-energise a part that is near a failure point, say like hitting the whitened area of an abs section with a heat gun?

~used to do this with the front section of my Tamiya Blackfoot after a frontal crash into a curb, heat up the section with a heat gun so the front frame bracket would last longer.

[Seanz0rz]

i suppose that might work, although there is a finite limit to the number of heat cycles, especially if reaching the melting point.

still streaming: RepRap - Seanz0rz (http://www.ustream.tv/channel/reprap---seanz0rz#)

[Obi..]

Is it done yet?

Is it done yet?

Is it done yet?

Is it done yet?

Is it done yet?

Is it done yet?

Is it done yet?

Is it done yet?

;) Gotta goto bed to goto a job I hate in 6 hours..please post finished pics since I'll have to miss out on the making of it.

[Seanz0rz]

yep ill post finished pics of it. ill be stopping after this print for the night. dont trust it enough to let it run unattended (im watching the live cast in another room though!)

still streaming at 1:14PM PDT...

[Seanz0rz]

so more on the spool later...

here it is!!!!!
http://i955.photobucket.com/albums/ae38/hamiltonfabrication/IMG_3573.jpg

top covered in silver sharpie to highlight better:
http://i955.photobucket.com/albums/ae38/hamiltonfabrication/IMG_3574.jpg

now, its far far from perfect. i would use colored plastic for this instead of clearish, it will look sooo much better, and i need to dial in some settings a bit more, but at least this time it didnt print mirrored!

[Seanz0rz]

streaming again at RepRap - Seanz0rz (http://www.ustream.tv/channel/reprap---seanz0rz#)

its sort of YOTDA related...

[some_odd_girl]

What is it? This is different than the kind of 3D printer I've seen before...

[Seanz0rz]

http://www.thingiverse.com/thing:10650

[Crinale]

How strong of plastic are the parts that you make? like how much stress can they handle without breaking?
still curious on this..

[Seanz0rz]

kevin, i dont have any way to test parts at home. maybe when i get back to school ill ask to do some tests.

so far, once they are cooled, they are incredibly strong. even the few thin and light pieces ive made are very very robust.

here is the approx. 2" size keychain:

http://i955.photobucket.com/albums/ae38/hamiltonfabrication/IMG_3575.jpg


ill have a chat with a few of the admins and see where they want to go from here...

[some_odd_girl]

Ooooooh, YODA. Haha, I get it now. The keychain is cool.

[Seanz0rz]

not sure what happened to the pictures above, ill look into it.

so an update:

ive designed and printed my first really functional thing:
http://www.thingiverse.com/thing:14620

it is a smart phone holder, attaches to my Go Pro suction cup, so i can use my android smartphone as a gps in the truck. all the buttons and ports are accessible and it fits snugly.

some mounts are 60 or so dollars, so ive really saved myself a bit of coin with this one.


in other news, senior project is in full swing, ill post more about it when it comes time to build. basically a plastic recycler/extruder that can be built at home by the average hobbyist.