3D Printing A Wheel
 

1678 is doing a test run of a full-size 3D-printed wheel; you can see it at http://www.twitch.tv/frc1678. We're using the MakerBot Replicator 2 we got through Donors Choose.

We tried this last night, but the filament snapped, and somehow part of it had gotten wrapped around the drive gear. In addition, more filament was clogged up in the nozzle head. Took me about 2 hours to fix. I hope this one goes better.

Re: 3D Printing A Wheel
 

PLA wheel? Interesting. Also, how large is the wheel? Looks like a 4"

Re: 3D Printing A Wheel
 

What % infill are you using?

Re: 3D Printing A Wheel
 

2429 just got a replicator 2 as well make sure to have your filament cable loose and unconstrained. also have you changed any of the heating settings?

Re: 3D Printing A Wheel
 

I saw the head move for about five seconds and then an ad popped up... turned it off at that point.

Jason

Re: 3D Printing A Wheel
 

Yes, yes it is, and yes.

100%.

That may have been the problem. We'd printed stuff before, but I switched colors for this piece. I tried a few heat settings, but the default 230C seems to stick best.

Sorry, blame twitch. Try using Adblock?

Re: 3D Printing A Wheel
 

I'm interested that you decided to 3d print wheels at all. Is this just a test, to see what kind of quality you get? If you're seriously considering using 3d printed wheels next year, could you talk a bit about the thought that went into the decision?

Re: 3D Printing A Wheel
 

Yes, it's a test. We think it's quite possible (based off the advice of one of our mentors, who has built many 3D printers) that an extruded PLA wheel will be strong enough to endure the rigors of FRC. Our hope is to be able to cut down on manpower and machining time. We use 2-inch wide wheels with 971's tread attachment style, which take our sponsors several weeks to machine out of aluminum. In the build season, this is unacceptable, so we're trying to print them instead (using a modified design, obviously). A 1/4 scale model held my weight without cracking. If you want, I can post renders of both designs.

Re: 3D Printing A Wheel
 

what resolution did you use fine,low,standard ? also have you tried putting down the big blue piece of tape that comes with it?

Re: 3D Printing A Wheel
 

High resolution, using tape.

Re: 3D Printing A Wheel
 

When will this model (likely) be done? Will you be making more to test an actual drive train, or just the one wheel? Either way, I am interested in seeing results.

Re: 3D Printing A Wheel
 

What is your problem with Vex traction wheels, other than the attatchment method?

Re: 3D Printing A Wheel
 

are you printing the wheel solid ?

Re: 3D Printing A Wheel
 

Tomorrow evening, and we'll test this one before deciding if we want to make more.

The attachment method.

Yes.

Re: 3D Printing A Wheel
 

o.o why not polyurethane casting and using hollowed version out of wheel to use as a negative because printing four or six of those wheels (at least) is going to be expensive

my math has it at 5 cents per gram if your using makerbot pla and 1.5 cents using an amazon competitor

Re: 3D Printing A Wheel
 

That comes out to be about $40-$50 dollars for two robots' worth of wheels. Not that bad, I think.

Re: 3D Printing A Wheel
 

Interesting. I am curious to know how long it takes to print this wheel. Did you use one of the OpenSCAD parametric wheel programs available or is this your design? Any chance of sharing the STL?

Re: 3D Printing A Wheel
 

Here are some renders.

Re: 3D Printing A Wheel
 

Very good job with those ribs! Looks like a very efficient and strong use of material.

Re: 3D Printing A Wheel
 

I know what I'm doing all night.

Re: 3D Printing A Wheel
 

Looking at it right now, looks like something messed up during the print

Re: 3D Printing A Wheel
 

There was a team at North Star last year that used 3D printed wheels... I think it was 2175. They had a sponsor print them with material stronger than what you typically get for home printers, if I remember right. You should get in touch with them and see how their experience went over the season!

Re: 3D Printing A Wheel
 

I got about half a second before the add popped up. I to turn it off.
Was something wrong with YouTube that made you put the video on this site?

Re: 3D Printing A Wheel
 

It's a livestream of it printing, I would assume the team doesn't have a fancy youtube streaming account. Nearly every streaming service has a start of video ad and the ad is only a few seconds long.

Re: 3D Printing A Wheel
 

We recently printed a pulley for our (Very Altered) KOP drive train to replace a lost one. We printed it with PLA at only 55% fill. I was worried that we did not do 100% infill, but its working fine with all the abuse the freshmen and I have put on it.

When we started experimenting with our printer i was surprised at how strong pieces can be if build correctly. I guess if a wheel breaks its as easy as printing a new one overnight. If you were to go to competition with printed wheels, make sure you bring extra.

Re: 3D Printing A Wheel
 

Printer is now making a squeaking noise too. I'd go check on it if I were you.

Re: 3D Printing A Wheel
 

Well, that blows. Looks like I'll be contacting MakerBot support.

Re: 3D Printing A Wheel
 

230 C is on the hot side for PLA. I am typically printing around 195 C. If it get's too hot it can burn and cause jams in the head as well. 230C is in the ABS material range.

If you need a hot layer to stick, set your slicer to put the first two layers down hot, then have it dial the temp back to what will still flow well at a lower temp. Or under your printer control you can pull the temp back as it is running unless the g-code has a temp setting at every layer.

For a stronger material nylon can be extruded as well, but requires a pretty hot temp to do so. Not all printers are up to that level of heat.

Randy

Re: 3D Printing A Wheel
 

It's not a video, it's a livestream. Twitch is the best place to do livestreaming for free and nearly all free livestreaming sites put a short ad at the beginning of the stream the first time you open it. They need to pay for the site somehow, not everything is charity.

Re: 3D Printing A Wheel
 

I don't know what caused this, but I do know what problems this caused. The piece of the wheel that got knocked off also dislocated the tube that routes air from a fan to the nozzle. Without this air flow, the nozzle overheated. This afternoon, I found the ceramic insulation surrounding the nozzle burnt off, and the kapton tape that held on the insulation melted to the nozzle. I'll be having some fun over break...

Re: 3D Printing A Wheel
 

We observed a similar issue with some of the Makerbot 2X's that the university's engineering program got about a week ago. One of the nozzles clogged, and the printer just kept going. It ended up "printing" in the air about 4-6 inches above the model when we stopped it.

Also, we've noticed a few of the prints have had peeling issues (where the model comes up off the kapton tape). While it hasn't affected the stuff we've been printing (more printer parts), it's something that shouldn't be happening. Have you guys been seeing anything similar?

Re: 3D Printing A Wheel
 

The Kapton Tape MELTED to the nozzle? I thought they used it because it does not melt. (Control F "melting")

Thats crazy scary.

Re: 3D Printing A Wheel
 

Your post encourages me, actually. I assumed that the brownish color of the melted-on plastic meant that it was the kapton. We were using white filament, but maybe some just got on there long enough to burn brown. Most of the kapton-insulation layer sloughed off when I touched it, so I can't be sure.

Re: 3D Printing A Wheel
 

I'm not sure if this is the cure-all, but we've found that EVERY time we start a print we Windex the platform and wipe it dry. Also make sure that the plexi cover is in place. The slightest of convection currents wreaks havoc on the prints and can cause them to release.

Re: 3D Printing A Wheel
 

Yes, white filament can burn brown. The tape wont burn (although I haven't used tape in months, as I use Aquanet on a glass plate instead).

I rarely find myself using .1 mm heights even when needing high precision prints. Usually 0.2 mm does the trick, or 0.15mm at the minimum. 230C should be fine

Recommend rafting to help the prints stick, if that was your issue. Also, you can try playing around with the custom slicer settings (edit profile) to change the thickness and print speed of the raft itself. Thicker base layers help it stick more!

I recently had the plastic fan part fail as well, it can be epoxied back together but Makerbot will send you a new one for free. Just MAKE SURE when you re-assemble, the duct is at least a few mm above the extruder nozzle tip. Sometimes outer parts of the print will warp upwards if building an overhang and that's what hits the duct.
Also, get used to taking the extruder apart and putting it back together. That's a standard maintenance task anyway which should be done weekly. After some practice, I get the stepper motor teeth opened, cleaned, and closed in under 5 minutes.

Re: 3D Printing A Wheel
 

Oh sorry -- I had to look at your failed print more closely. Is that a single wheel that failed or a second next to it?
I saw you have rafting, but the model itself may have had an issue during compile.

I highly recommend you ALWAYS run your stl outputs through Netfabb before printing them, to avoid such errors.
http://cloud.netfabb.com/

the other possible issue is you could have been "air printing" a couple layers before filamenet continued to extrude -- thats a matter of extruder motor gear cleanliness and ensuring there's enough load on the spring-loaded drive block.

Re: 3D Printing A Wheel
 

I'm intrigued...what does this process do? I have been exporting my files as .stl from Solidworks, and using the Makerware software to put them onto the sd card. What change does the netfabb site make to the files?

Re: 3D Printing A Wheel
 

It finds "holes" in the model that end up confusing slicers, sometimes to the point where they will not print in that location at all or even worse, start printing all future layers offset from where they are supposed to be. I can show you several examples of this if interested.
Netfabb replaces those holes with real triangle geometry and "unifies" the mesh.

I will say that the majority of my errors from original drawings come as a result of merged parts (via assembly, output as an .stl for single print), or for unusual geometry particularly from splines, and most especially when I export from Autodesk Inventor (for some reason). I recently switched to Solidworks and have had little issue yet, but I still run everything through netfabb and the program reports on its findings.