Practical 3D printed parts
 

With the recent addition of 3D printers to the FIRST Choice store are team has been wondering what parts can be made more efficiently on a hobby 3D printer than traditional tools (lathe, mill, CNC mill etc)?

The only practical thing we've come up with is rough spacers, particularly ones with tapers.

Re: Practical 3D printed parts
 

3D printers are great prototyping tools. A part can be cranked out on the machine with no oversight required. Parts that may not be make the final robot can be made and tested this way.

In addition to the miscellaneous plastic parts that can be made, definitely look into resin and urethane molding, or even aluminum casting, using the 3d printer to make the mold masters or mold halves themselves. Parts of pretty significant strength can be made this way.

Re: Practical 3D printed parts
 

This is more of an FTC application but I designed and printed our flag turner on a 3d printer. I think for the majority of FRC it may not be as practical but there are possibilities.

Re: Practical 3D printed parts
 

I'm currently, with the aid of some members of 449, checking out the feasibility of printing GT2 pulleys, which would be a huge cost-saving measure and allow a lot of flexibility over COTS aluminum pulleys. I'll report back on how it goes, if you'd like.

Re: Practical 3D printed parts
 

Spacers, plastic gears, and plastic inserts to reinforce sheetmetal (see pictures linked) can be useful parts made by a 3D printer.

https://fbcdn-sphotos-d-a.akamaihd.n...71422371_n.jpg

https://fbcdn-sphotos-c-a.akamaihd.n...99420493_n.jpg

The bright orange plastic parts were 3D printed. They were used kind of like spacers between the sheet metal of the bridge appendage, to support them so they didn't cave in.

I believe 4334 3D printed some pulleys for their 2013 drivetrain, but I'm sure Joel/someone else from them can chime in.

Re: Practical 3D printed parts
 

In addition to the above suggestions, encoder and other sensor mounting brackets are another common use.

Also, remember that objects that are 3D printed via the FDM process (where ABS/PLC plastic spool is melted and extruded into the printed object) are weak in between the vertical layers. There are two ways to deal with this: 1) accept this and design/layout the parts with this in mind; or 2) design hybrid parts that use other parts or hardware to reinforce the 3D printed parts.

One final note: FDM process 3D printing is generally pretty slow. It might take 12-24 hours to print some parts. Some parts may actually be much faster to make via drill press/band saw/lathe/mill or purchase as COTS parts. Make sure you balance your resources. You don't want to design so many 3D printed parts that it takes 7 weeks to print them all. :ahh:

Re: Practical 3D printed parts
 

That's interesting, I've seen people cut HTD pulley profiles on a CNC but GT2 pulleys have curves that would be difficult to cut without a 4th (or even 5th axis). It would be interesting to know how they obtained the proprietary GT2 profile.

Re: Practical 3D printed parts
 

It looks possible to print the pulleys easily, http://www.thingiverse.com/thing:16627 but they would need to undergo some testing before use on a robot. What would help teams though is that they could print out the pulleys and use them if the part they want gets back-ordered. I am also wondering about any teams that used 3-D printing with gears for low load applications to see if they held up.

Re: Practical 3D printed parts
 

I pulled the CAD of bbman's website, with the hope that the profile is correct (or close enough to correct that it'll work, the fact that their CADs have different profiles for HTD and GT2 pulleys seems to indicate that they're not just using a single erroneous profile for all of them).

I had heard that other teams had successfully machined pulleys from CADs obtained this way, so it seems worth a shot.

If it doesn't work, I'll check out the parametric pulley link nicholsjj posted (thanks for that, by the way) - though I don't have OpenSCAD on my computer right now.

Re: Practical 3D printed parts
 

See attached picture. Material is ABS. No idea what the specs were when they were printed...whatever our sponsor had set up for whatever they had recently made.

I copied the GT2 profile off one of the websites (sdp-si maybe? it's been so long now I don't remember) and the printed pulley meshed very nicely with a GT2 belt. Just haven't had the ability to test the strength of the pulleys on a drivetrain yet. The printer I have best access to is an FDM...great insight mentioned above. For a drive pulley (off a gearbox) my plan was to mate an AM hex hub to the printed pulley (similar to what AM currently lists on their website for the 2013 chassis). I would add another circular hole pattern to drill and tap for #10-32s on the AM hub. The wheel pulleys I was planning on attached to a WCP dead axle hub. The side you can't see (resting on the table) has a bore for an R8 bearing. An R6 bearing would go in the WCP hub. No chance to test these yet to see what breaks...hopefully soon.

Re: Practical 3D printed parts
 

Art's First point is probably one of the most important things to keep in mind while printing parts. Depending on the exact geometry of the part, printing in the strongest orientation (the layers do not want to pull apart from one another) is not always the orientation that will most accurately produce the part. There are some interesting ways around this, either splitting the part into multiple parts where each sub-part is optimized for geometry or strength, or as Art said, you can make a hybrid part where some other component reinforces the weakened area.

I used your method exactly in Decemeber-ish of last year to make a prototype pulley (ignore the versa keys...) and the profile was pretty darn close to perfect.

https://db.tt/WT0HnkDQ

https://db.tt/Wd92gCkg

From what I saw, the printer ran a few thousandths over while making the teeth, so if I were to make that exact pulley again, I'd probably remove a couple thou from the tooth profile and see if it cleans up with tooth engagement at all. All in all, wasn't a bad final product, IIRC, the teeth being a touch big was only noticeable once the belt wrapped more than 120* or so.

Also, as far as I can remember, the pulley was surprisingly strong, we clamped the belt in a vise and beat the pulley up a bit and there was little to no permanent damage. It's worth noting that the pulley was printed from Ultem (polyethermide) which is something like 2.5-2.75 times stronger than ABS in the same machine. Odds are, ABS should hold up just fine, but if I were using ABS, I'd make sure that at least one wheel was directly driven from the transmission or something.

While we're on the subject, here's a picture of one of the larger print runs done for last season's robot:

https://db.tt/tqhDMaaS

If I remember correctly, that build took somewhere around 11 Hours to print from beginning to end, including warm up time. Starting from the left most side:

-(4) parts with rectangular holes were servo brackets that were printed a touch too thin to hold up to handling before the servo was mounted,

-(2) spacers to offset a sprocket from our shoulder joint - they had the standard 1.875" hole circle printed into them, along with a 1.125" OD protrusion on one side to pilot into a bearing bore, and on the other there was a 1.125" ID bearing bore to hold an FR8 Bearing,

-The large clam-shaped parts on the right side were a spacer for our shoulder's pivot. There were (6) Hexagonal pockets printed into the spacer to hold 10-32 threaded inserts along with some neat cutaway geometry to allow #25 chain runs through the pivot to our climber. I stood on one of the shoulder spacers to see what would happen, and it didn't move a bit.

Also, here's one of the encoder mounts made over last season - initially, this was the 'standard' mount used on both our drive and shoulder although the shoulder's final encoder configuration was a bit more complicated (cooler) than this: https://db.tt/kJqK0kE3

Re: Practical 3D printed parts
 

We have a uPrint SE that we love to prototype parts with and we made some spacers that we used on our 2013 robot. Some of the things that we made were custom shaft attachments/couplings for the window motors.

This year we are working on our 6 wheel tank drive with 5mm HTD belts. We were looking at using the VEX Versa Hubs with the 42 tooth HTD pulley from Andy Mark. We decided to combine both parts and we now have an integrated pulley with hex drive that attaches to the VEX traction wheels. We are pretty excited about it but we will continue to test for strength.

We spent a lot of time researching how to create the actual 5mm HTD profile for the pulley and it took a few attempts to get it right but this 42 tooth profile is perfect now.


I see no reason why these will not be on our actual robot this upcoming season.

Re: Practical 3D printed parts
 

Great thread, thanks for starting it!

Re: Practical 3D printed parts
 

Here are a few ideas of what we have printed over the past couple seasons:

-Our 2012 shooter wheel was custom molded to give us the exact shape/diameter we wanted on a wheel with almost all of its mass on the outside rim. To make this wheel we 3D printed a mold, machined a hub, and poured the urethane around the mold. Oh yeah, and we embossed '125' in the wheel, because why not? (See attached images)


-Also in 2012, we 3D printed components to center the ball as it went up our lift into the shooter wheel. This ensured we caught the ball in the same place on the wheel each time.

-Again in 2012 we printed a gearbox to power our intake/elevator. It utilized 2 FP motors and the first 2 gear stages of the plastic FP gearbox. We ran through 2 quick iterations of the gearbox, and it worked flawlessly all season.

-This past year we printed 'cable guides' to mount over the pulleys on our lift. This prevented the sailing line we used to lift our elevator from jumping off the pulleys themselves. Again a couple iterations of these and they worked flawlessly all season.


There are so many applications for 3D printing in FRC. We've been using printed parts for years, and we're always finding new applications. Keep your eyes open and dont be afraid to try something out (just make sure you give yourself enough time to implement a backup plan if something goes awry).

-Brando

Re: Practical 3D printed parts
 

Brandon,

I'd really be interested in more details of the urethane pouring process and pictures of the mold, as this is something I've never done. Your finished product looks good. I'm also interested in seeing the 3D printed FP gearbox if you have a picture.

Thanks.

Re: Practical 3D printed parts
 

I've got plenty of pictures back on my home PC- I'll circle back tonight and post them.

-Brando

Re: Practical 3D printed parts
 

Just in this one picture there are many 3D printed parts:
- wheels on end of arm that set floor height.
- bearing blocks on active leading edge (inside wheels)
- finger grippers on 3/8" round, keyed shaft
- crowned flat belt pulley on keyed 3/8" shaft (under flat belt)
- finger grippers on 1/2" hex shaft
- bearing blocks on main arm pivot
- drivetrain gearbox dust covers (near side yellow, far side purple)
- camera/light ring mount (purple, on underside of shooter)

We're to the point now where we'll make just about any nonstructural part with the 3D printer rather than spending fab time to make it. Thus far, we haven't broken any plastic parts. The bearing blocks were an experiment to see if semi structural parts could hold up if made beefy. These have lasted through two off-season competitions and at least half a dozen demos.

Re: Practical 3D printed parts
 

What material do you use?

Re: Practical 3D printed parts
 

Here's a project my senior students worked on. I don't have access to the printed part (at school right now and I'm home), but the second one fit extremely well to a VEX Versa hub. The original intent was for our 6 WD test bot and the driven wheels would used this design. Last year's bot used an 8" drive wheel and 6" driven wheels, but we used chain drive. This year we want to use belt drive and we couldn't find the tooth ratio we wanted so we started to draw this in Inventor. The tooth profile wasn't too hard to get, but the hard part was getting the right diameter for the circular pattern of the tooth to work out in Inventor and in real life. So, this one is 39 tooth to match the Andymark double pulley, so if we use this design, wheel sizes will be common. But I'd like to cheat the driven ones to be smaller to increase the wheelbase of the bot. Therefore we redraw it with the right tooth ratio and off we go. The problem will be getting a smaller tooth profile to fit with the part. If we keep the 39 tooth drive with a 6" wheel, we need a 26 tooth driven for a 4" wheel. Not sure how that 26 tooth will match up with the Vex Versa Hub Pattern. But in the classroom that becomes an absolutely great design exercise to go through!

BTW, Project Geometry is your very good friend in Inventor. Just make sure you have the parts in an assembly, constrained correctly, and then you can modify the part you are working on to match very, very well with the mating part.

Re: Practical 3D printed parts
 

ABS is a very nice plastic and is very strong. After 3D printing technology improves enough, it will be feasible to start producing things like pulleys and other highly used parts. Pulleys should already be an easy one to 3D print as long as you use an aluminum or steel axle because the load is distributed throughout, reducing the stress on the plastic!

I have gotten many things printed in ABS. They are very strong, and lightweight and take compression forces quite well, as long as there is no sheer or bending force on it. My Stirling Engine crankshaft broke because of the high sheer force I accidentally placed on piece, when removing the building material. I should have used an abrasive instead, to get rid of the black building material.

Our school has either 2 or 3 of those Dimension 1200ES printers! Out of that, we use only one!

Re: Practical 3D printed parts
 

Lots of good examples out there. I am impressed with everything Triple Helix has done with the parts.

Last year we had only started getting into printing. On the robot we printed a couple of things. One was some bushing which fit inside the outer tube of our lift and let the inner tube slide up easily. We also, printer out our gyro holder and some thin flexible fingers for our shooter to help keep the frisbees aligned.

Oh, and we printed out a bunch a little key chain wrenches to hand out.

This year we are looking for opportunities. I can certainly see some manipulator parts depending on the game this year.

For FTC we have a couple of teams already doing some things. One team CAD'd and printed flippers to pull the blocks into their bot. We also had some of the old clip style samanthas so one of the kids found a CAD of the back and we added some bolt down tabs. (Pic attached)

We also started experimenting with plastic parts with hole textrix hole patterns. Specifically to get different heights through different thicknesses (pic attached).

As another poster commented layer separation can be a problem. For other projects at home (like the robot hand I posted earlier on another thread) I have used acetone painting and acetone vapor baths (safety is a huge consideration). Other than that though ABS is very strong. Even with 20% honeycomb in-fill and 3 shells the parts I have printed are very strong. Just look at how well the 3d printed extruder gears on RepRaps hold up. The one on my Prusa I2 has thousands of hours on it.

The other issue mentioned is print time. I have had parts take 6-8 hours to print (parts of the robot forearm) and an hour or so is not un-heard of and you will have failed prints usually after half the print. If you have other CAM capabilities (CNC mill, laser cutter, etc.) they can be much more efficient. And yes the commercial printers generally can be run faster than the RepRaps we use but for complex prints.

The other big limitation is build area. The printers we use have an effective build area of 180mm x 180mm x 170 mm. So you may need to cad bigger things as separate parts that can be joined. ABS glues very well with Acetone and bolts are easy.

I really look forward to seeing what neat ideas teams come up with. I hope to see more threads like this one. Maybe, we should look at tagging FRC and FTC parts when posted on Thingiverse or having a standard thread hear on CD so folks can always see what is new.

Re: Practical 3D printed parts
 

Cool stuff. Can you post some close ups and/or STLs of these parts?

Oh, and what kind of printer do you guys have?

Re: Practical 3D printed parts
 

Hi! I'm from FIRST team 3824, and we have been working with Oak Ridge National Laboratory for the past four years. Two years ago, we had the very first all-printed robot. Last year, we had a printed robot with carbon fiber. We definitely have benifitted from the use of 3D printing, and we are partnering with 3D Systems on the development of a new website for FIRST. It will have the ability to upload and download parts designed specifically for the kit of parts. This will enable us to help new teams take advantage of the technology and also share models.

Another use of these printers is fundraising. You can make and sell trinkets, keychains, cell phone covers, etc. to make money for your team. I believe this will be the most useful tool your team will ever have. You can make customized cell phone covers for a few dollars and sell them for $20 to $30! Last year we helped make Frisbees to give out at Nationals and the Smoky Mountain Regional (SMR). I'll start uploading pictures to get teams thinking.

We even have a tagline that is 3D printed which says "Made in America" in Chinese. So, be creative in how you use the printers beyond just making parts for your robot

Re: Practical 3D printed parts
 

Here's an example of a printed belt pulley that interfaces with an AndyMark shaft hub. This will let you make any sized belt pulley. We will start uploading these models to 3D Systems' FIRST website.

Re: Practical 3D printed parts
 

Here's an example with some printed brackets connected by carbon fiber rods. We used this on our robot last year.

Re: Practical 3D printed parts
 

Here is a picture of our printed robot from last year.

Re: Practical 3D printed parts
 

Here is our printed robot from two years ago also

Re: Practical 3D printed parts
 

Our printer was really useful this year.
Attachment 15476
The banebots motor mount was 3d printed, the pulley that is on the banebots motor was 3d printed (it fits over the gear on that motor), the pulley on the shooter wheel was 3d printed, and the shooter wheel itself was 3d printed. We had made some shooter wheels out of HDPE, but as they were cut they would warp because of internal stresses from the manufacturing of the plastic. The 3d printed wheels were perfectly balanced and improved our accuracy.

The 3d printed big pulley was printed in 12 hours because we didn't want to wait for the order to come in. The little pulley was the most useful because of the gear-shaped hole in the back. Originally, we tried "modifying" the 4:1 P60 gearbox to become 1:1, but it was inefficient. The 3d printed pulley let us interface directly with no transmission relatively easily.

Re: Practical 3D printed parts
 

Are these parts printed in Ultem? Looks like you had some serious access to a Fortus machine!

-Brando

Re: Practical 3D printed parts
 

Yes they are! We have the privelege to work with Oak Ridge National Laboratory, so we have the ability to print with Fortuses. We allow teams in the area to print things as well, so we're not selfish with this technology. It is always better to have more collaboration with other teams.

Re: Practical 3D printed parts
 

Our team only used a few 3d parts this year:

The first part that we made was a cover for the leads on a Banebot RS775 motor. The way we had attached the motors the leads were just sitting out in the open, and they could have been easily damaged. So we created this piece that we zip-tied onto the motor that covered the leads.

The second part was a little box that attached to the top of our 8 slot cRIO that we could attach the digital sidecar to. We had seen another team do something like this, and we implemented it to save space. It is actually 5 separate pieces, the large box in the center where the sidecar is actually bolted to, and the 4 legs that are press fit into the sides of the box and cRIO. If we ever need to remove it from the cRIO, we simply remove the legs and it comes off easily.

Re: Practical 3D printed parts
 

Sweet! It is always awesome to see someone using this technology to creatively and efficiently solve a solution. Hopefully next season you can find more ways to implement this technology into your robot!

Re: Practical 3D printed parts
 

Standard ABS filament for a Makerbot 3D printer.

OWilliamson, do you have the link to the part for the sidecar mount or where I can find it?

Re: Practical 3D printed parts
 

[quote=Gregor;1305458] The bright orange plastic parts were 3D printed. They were used kind of like spacers between the sheet metal of the bridge appendage, to support them so they didn't cave in.

Re: Practical 3D printed parts
 

After the CAD team is done, print out the robot, give a copy to each mentor and put one copy on a bookshelf to remember the year! :D

Re: Practical 3D printed parts
 

Linking Team Titanium's brilliant CRio protector here...

http://www.chiefdelphi.com/forums/sh...d.php?t=125265

http://www.thingiverse.com/thing:233663

...and adding our own Jaguar Stacker:

http://www.thingiverse.com/thing:237012



We will probably change to Talons sometime - but we still have such a large stock of Jags, and get two more each year, who knows when that will be?

Re: Practical 3D printed parts
 

I have tried to tag everything on Thingiverse that is for FRC with FIRST Robotics and FRC. We have printed our Versa Gearbox motor mounts on a solid abs setting, and they have worked so far.

Re: Practical 3D printed parts
 

We like to use 3d printing for prototyping and replacing/modifying COTS plastic parts. We are currently using 3d printed parts to interface with colson wheels, as thicker versa hubs, spacers, and as a replacement for the battery mounting bracket. In the past we have printed pulleys, wheel inserts, and even 80-20 end caps.

Re: Practical 3D printed parts
 

We made a load of hex spacers yesterday for use on our competition robot.

Re: Practical 3D printed parts
 

So far, about half of our practice bot is made of printed parts, mostly because we needed more stuff from vex pro than we could reasonably get in time. Nearly all our gussets, some of our HTD pulleys, and our battery box. Of course, the competition bot won't have all this stuff (though the box will probably stay), but it made our build much quicker and more economical.

Re: Practical 3D printed parts
 

Re: Practical 3D printed parts
 

We print out battery holders. They have our logos on them and they have strain reliefs for the wires. Plus, it makes them way easier to hold and are plenty strong.

Re: Practical 3D printed parts
 

Could you upload an example image of the CAD or of a real life example? That sounds like an interesting use of a printer.

Re: Practical 3D printed parts
 

I tried looking for a picture, but I couldn't find one. I'll post a picture of one tonight or tomorrow, as well as maybe the STL file

Re: Practical 3D printed parts
 

We've printed a few things that have come in handy.

First, we printed some brackets designed to hold 4 pneumatic storage tanks on the robot. It was a pretty nice solution overall, and allowed us to stack them much easier than we otherwise would have been able to (half hour to design, then a day worth of printing instead of several hours of manual work to make something similar by hand).

Then one of our students came up with a design for a winch that really looks awesome. We used a winch last year as well, but that was all hand made and had issues occasionally where the strap would jump off and get tangled. I plan to get some pictures of that setup and the new setup for this year to show a comparison - your mind might be blown at how big a difference it is, and again it saves work hours on the robot! The winch last year, for all its simplicity, took a long time to actually get together. This year, all the complexity is designed in half an hour and printed!

Re: Practical 3D printed parts
 

We used ours to print shaft collars... lots and lots of shaft collars... :)

Re: Practical 3D printed parts
 

Us, too. Delicious, lightweight, very very purple hex shaft collars!

Re: Practical 3D printed parts
 

We're printing a radio / camera / sensor tower that mounts onto the corner of our drive frame. We will still probably protect this with an overall polycarbonate shroud once everything is on the robot.

Re: Practical 3D printed parts
 

11's kids printed off what they're calling "Talon Towers," just a simple way to stack Talons for some space savings.

https://www.facebook.com/photo.php?f...type=1&theater

http://i.imgur.com/LfiXK5t.jpg

Re: Practical 3D printed parts
 

Slightly off topic, but I had one of our electronics guys ask me about how well that would work without fans. Have you run that setup (or similar) before, and if so, id you notice a performance difference between the Talons with fans or Talons without fans?

(I'm not an electronics guy, so I'm just repeating his questions).

Re: Practical 3D printed parts
 

We printed several hex shaft couplers for the roller intake. Some of them broke, so we made more with tighter tolerances, more flexible material (Nylon) and higher infill. We'll see if the new ones break. We'll move to aluminum eventually, maybe.

We've made several encoder mounts, one of which I posted to CD. The rest could be acquired COTS if desired.

Some of the ideas we've had would require a non-linear profile for a roller to roll through as the launcher did its thing, and we'll 3D print them of the linear concepts ever get around to working at all.

LOTS and LOTS and LOTS of hex spacers for the roller intake.

Thought about making a clevis that would rotate a pneumatic cylinder 90 degrees on the tail so it rotates properly while also re-orienting the ports, but found a simpler solution with angle aluminum. For the roller intake, of course. (Can you tell that I led the roller intake subteam? :D)

Will poke at making pneumatic storage tank mounts since they tuck away nicely at a spot between the rollers (when they're down) and the frame.

Re: Practical 3D printed parts
 

I've heard 0 issues about Talons, regardless of them having fans or not. I don't think our students are concerned, but we will keep an eye out for any issues.

Re: Practical 3D printed parts
 

We ran stacks of 3 talons without fans last year on a 6 cim drivetrain through 3 competitions and eliminations at all of them with minimal time between matches with no issues.

Re: Practical 3D printed parts
 

Our team did this as well -- and it is part of what allows to raise the flag so quickly-- < 1 sec. Can you post a picture of yours?

Re: Practical 3D printed parts
 

Does anybody have a bracket or mount design for a mini-cim? We have a MakerBot 3d printer and would like to print out brackets (for a mock up testing base) for the cims.

Re: Practical 3D printed parts
 

Not exactly sure if this is what you want, but Andymark sells a bracket that mounts CIMs and mini-CIMs.

Re: Practical 3D printed parts
 

we would like to use the 3D printer because this is only a mock up. this will not go on the actual robot.

Re: Practical 3D printed parts
 

How durable are 3D printed parts? Our team doesn't use them.

Durability of 3d prints, as with most materials:

When designed correctly, they can be infinitely durable.

When designed incorrectly, they will fail immediately.


Comparatively, usually less than a comparable machined nylon part.

Re: Practical 3D printed parts
 

You can download the step file from Andymark to get all of the layout and make any modifications you want and create your .stl file from there to print them. If you leave them thin they will most likely have a lot less stability than their metal counterparts.

Re: Practical 3D printed parts
 

We printed a wheel to fit inside a roller mechanism that has an opening for 3/8" hex shaft. Added our logo and some FIRST decorations just because we could.

Re: Practical 3D printed parts
 

Our team has 3d printed VEXpro Gussets for our Versaframe. These have proven to be incredibly useful for prototyping and have held together our robot very well. With shortages of materials and unreliable shipping time, the gussets we printed have made a great substitution for the VEXpro ones. Only problem is that the holes are always a little bit too small but drilling them out is no problem.

Here: Attachment 16029 You can see some of the gussets we have are non 3d printed for extra support but the colored ones we printed on our Makerbot.

Re: Practical 3D printed parts
 

As promised, our winches.

This year's winch utilizes 3D printing pretty heavily - the spool is printed, as is the webbing guide. This let us quickly and easily put everything into a small package for use on the robot.

Last year's winch was all hand-made. First, we had to cut the sides for the spool. Then we had to get them bolted together and into some shaft collars to make them stay in place. Then we had to improvise a guide to try to keep the webbing straight... and it ended up occasionally getting off the spool and all tangled up.

Re: Practical 3D printed parts
 

The yellow one is last year's and the purple one is this year's new, more beefy, battery handle

We are still working on the printing. We are trying to make it more easy to print

Re: Practical 3D printed parts
 

That's great! I thought of making something similar for our batteries a few weeks ago, but there is no room for them on our robot...

Re: Practical 3D printed parts
 

How do you put it on and take it off the battery? If I'm interpreting what I see correctly, it looks like you need a screwdriver (and likely a nontrivial amount of time).

Re: Practical 3D printed parts
 

Yes, that is correct. Its not to hard to get it on, and it helps save your hand and makes it easier to carry the batter with, let's say, the driver controller::safety:: :rolleyes:

I will try and get the stl Out asap

Re: Practical 3D printed parts
 

Meaning it stays attached to the battery at all times, I guess. Very cool.

Also battery-related, I wish I had the 3D model for this.

Re: Practical 3D printed parts
 

Please make sure you note: Per R5, a handle like that is not considered part of your battery assembly, and must be included in your robot weight in all configurations used. Personally, I think it's a great idea to have a good way to carry the battery, but if you leave the handle on the battery when it's in the robot, it becomes difficult for inspectors to handle something like that within the rules as they are written. If that's the intent, I would recommend asking how it should be handled (pun not intended) on the Q&A.

Re: Practical 3D printed parts
 

This year 4183 has had access to an laser cutter that is housed in the same work space as us, and it has been extremely useful. This year instead of ordering our gussets and waiting for a week before they come in and we decide we need something different, we have been able to make plywood gussets in minutes and immediately attach them. We have our practice bot held together by these plywood gussets.

Re: Practical 3D printed parts
 

Not very practical (yet!?), but 1678 tested out some 3D printed wheels this off season.
See here.

Re: Practical 3D printed parts
 

This year, the Battery Mounting Kit http://www.andymark.com/product-p/am-0477.htm was not included in the KOP and I wanted to print one. Before I spend time measuring it and drawing it in CAD (no CAD file on andymark's site) I wanted to see if anyone else had already created it and would be willing to share? Any help would be greatly appreciated!

Re: Practical 3D printed parts
 

You can still find this item in the PTC 2013 Ultimate Ascent Kit of Parts.

I converted it to .stl the other day, I'll see if I can find it.

Edit: Here is the .stl file.

Re: Practical 3D printed parts
 

We made modular, stackable towers for our victors, with integrated pwm clips and zip-tie/strain relief holes.

Just got the first few assembled and thus far we're quite happy with them!

Re: Practical 3D printed parts
 

We made a battery mount that is the same dimensions as the Andymark one. The model is designed for 3d printing and is very durable, it can hold 10lbs no problem. The STL is here and the Solidworks part is here

Here an example printed in Stratasys VeroRigid plastic. You should have no problem with other plastics though.

Re: Practical 3D printed parts
 

We use our 3D Printer for both our FRC team, along with the the FTC Team. Right now though, the FTC bot has more 3d prints than the FRC bot does.

Just seems easier to use it for an FTC bot then a FRC bot.

Re: Practical 3D printed parts
 

Parts made so far with the 3D printer for use on our final robot:

- Battery Mount
- Camera Mount
- Drive mount with bearing that holds our wheel + gearbox together (not load bearing)
- Custom boxes to hold gyro, other sensors, beaglebone controller
- Custom-angle brackets
- Hub for the Denso window motor

Planned usage of more custom parts:
- Wire harnessing
- Control System shielding
- Possibly pneumatic system mounting

Can post photos if interested

Re: Practical 3D printed parts
 

I'm sharing three of 222's currently 3D printed parts on our 2014 robot that I feel will benefit other teams at this time.

A zip folder has been attached to this post and contains .stl, .ipt, and .stp file formats for each part. Two of the parts (.ipt format) have team #'s suppressed. If you want to add your own just unsuppress the text and modify as desired.

1: Nasson pressure switch mount.

Mount the mount as desired using the two holes. Once mounted clip in the switch. For extra security secure switch and wiring with ziptie.


2: VexPro 1x2" extrusion end cap.


3: Clippard air tank to VexPro 3 CIM ball shifter mount.

Mount two of these to the top of the 3 CIM ball shifters using 1/4-20 bolts. Insert tanks. Zipties may be used around the tanks to keep them from slipping back through the mounts easily.


For those wondering all of these parts were printed on Stratasys FDM 3D printers in ABS.

Re: Practical 3D printed parts
 

I can attest to the strength of well designed PLA printed parts.

Team 801's prototyping division has made entire gearboxes before (with the exception of the gears, axels, and bearings) using a Replicator 2 at 20% infill. As far as I'm aware, we have yet to break any of our casings or mounts despite the 2 months of testing we out them through. Also, Children of the Swamp 3D printed their wheel mounts last year and I don't think they broke any mounts all season.

Re: Practical 3D printed parts
 

I finally got around to uploading our Victor tower. Here it is:

http://www.thingiverse.com/thing:242644

Re: Practical 3D printed parts
 

so spce is very limited on our robot this year for electronics. Saddly, we never purchased a 4 port cRIO so we are still stuck with same old long one. So to save space on the electonics, we are mounting our side car on top of the open ports on the cRIO. A 3D printed mount was created to hold in place on the cRIO. The part wasnt printed on a maker bot but on a larger, industrial printer.

Re: Practical 3D printed parts
 

We have printed a lot of 3d components for our bot so far, but one stands out as the coolest...
Here's a teaser of our coolest 3d printed part...

See if you can guess what it is!

Re: Practical 3D printed parts
 

Our team made a small 3d printed cam with a half inch hex center. We plan on using this to hit a limit switch once per revolution to tell us when our catapult has reset.

Re: Practical 3D printed parts
 

Our current list of 3D printed parts include:
Spacers
2x1 End Caps
Catapult limit switch cam
E4P encoder mounts for WCP single speed shifters.
Camera Mount
Attempted fix to our button maker.

We are really liking the capability to make odd parts quickly and efficiently.

Re: Practical 3D printed parts
 

Could someone post a picture of a 3d printed camera mount? Just looking for ideas.
Thanks

Re: Practical 3D printed parts
 

Here's another part.

A VexPro 3 stage gear cover. It helps with safety and keeping the grease where it should be... It also keeps the electronics guys happy! :D





File is attached below in the .ipt, .stp, and .stl format.

You may need to change the design or length of the legs to account for your drive chain or belt. Also you can adjust the clips so they actually clip onto the rods if you wish, but it can be secured fine with a ziptie.

Re: Practical 3D printed parts
 

The 3D modeling isn't the best on this one. Also it hasn't been fully printed yet to confirm fitment. There is a 90% chance you will want to change the design anyway. It is designed for the Axis M1013.

The intent is to slide the camera in from the top and secure it using the rear integrated screw to pinch the plastic housings together with a nut.

I've attached a .stp and .ipt for you.

Re: Practical 3D printed parts
 

This one is a bit complicated, the programming team requested the ability to rotate the camera 31 degrees to the right and left of center depending on which auto program we ran.

The part that holds the camera and blue part are 3D printed, the rest is common hardware except for a rather interesting part. http://screencloud.net/v/tAqD
http://screencloud.net/v/5Jhe

The small piece of what looks like threaded rod embedded in the clear part that holds the camera is a spring plunger. The blue block is bolted to the robot and has 3 indents in it, one for -31deg, one for looking forward and one for +31deg, as you rotate the mount about 4 inch 10-32 the spring plungers snap into the indents locking it in place.

Re: Practical 3D printed parts
 

Seriously, when it comes to mounting encoders, using 3D printed parts saved a lot of time and effort. Another useful application is to cover print a part that can press into and cover the open end of conduit or other metal tubing.

Re: Practical 3D printed parts
 

We designed and 3D printed a part to mount encoders, too!
It made mounting magnetic encoders in several places on the robot a lot quicker and easier.

Re: Practical 3D printed parts
 

If you look up my username on Thingiverse, you will find a 1/2 inch hex shaft-to-arm attacher that we used for a while.

Here's the link: http://www.thingiverse.com/thing:254208

Re: Practical 3D printed parts
 

Here is ours. A simple angle bracket to hold the camera. Another part to hold light rings.

Re: Practical 3D printed parts
 

Sure they're practical. We've been using 3D printed wheels since 2010.

Re: Practical 3D printed parts
 

All of our 3D printed parts can be found on thingiverse in our 2014 collection: https://www.thingiverse.com/team2177/collections/2014

We have 4 distinct parts for this year:
Battery plugs
These have "Charged" and "Not Charged" on them, allowing you to have plugs in every battery while still indicating the state of the battery. Bonus points: Print the "Charged" in one color and the "Not Charged" in another!

Pneumatic storage tank holder
Designed to hold 4 tanks in a square pattern, can also be adapted to hold 2 stacked.

Ball Roller
We designed a roller for a 1/2" hex shaft. It has a curved surface to match the ball, and is 12" long (printed in 3 segments). Please note - you'll want to put something on it, like spray rubber, to aid in traction with the ball!

Winch spool
We're using a winch to pull our catapult down, utilizing 1" webbing. The spool prints in two parts, is designed for a 1/2" hex shaft, and has recessed 1/4" holes to secure everything together. It also comes with a guide that fits over the spool (with clearance holes for the 1/2" hex shaft) and helps ensure the webbing gets placed on the spool to avoid tangles. Obviously, it has a lot of compression force on the winch when it works, so we recommend using 100% infill!

Re: Practical 3D printed parts
 

Re: Practical 3D printed parts
 

-Our "teeth" on our arms
-Encoder mounts
-The bushings on our clutch-winch
-Our control board: http://www.chiefdelphi.com/forums/sh...66#post1349166