Anyone own a 3D printer?

[njmr2fan]

My boys dragged home a beat to hell Go Kart 2 summers ago. Its the first vehicle their restoring on their own. They're 8&9 so I still think they're off to a good start even though its their 3rd summer. I need a simple plastic part printed that I can't find anywhere. Thought maybe someone here could help. If my Dad still had his machine shop he could have made me a dozen of these out of aluminum within an hour...

 

[Beachbummer]

I have one. You may find https://www.3dhubs.com/ will find someone locally that's a pro...and it's pretty cheap. My printer is pretty small, so I may or may not be able to print it. Do you have a design of the part? Maybe someone already made it? thingiverse.com ?

 

[Bluewater272]

I have one, depending on the specs and what you need it to stand up to, I may or may not be able to help.


www.shapeways.com is another good place to look, can even have things printed in metal.

 

[Wisefam22]

Whst you need, I got buddy who can print about anything. Well his brother, I think he started using some type of carbon mix in his.

 

[njmr2fan]

Let me snap a photo of the part tomorrow and show how its used. It's a simple plastic cap with that surrounds the "roll cage" bars and has a saddle washer concave shaped washer on one side. Here's a good idea of what it looks like.

The bottom side of this photo would be where the 7/8" tube would fit in about a half inch deep. The whole piece is about 1" tall. If someone can print it, Ill send them a clean one to scan and pay for the work.

 

[haknslash]

I can print it with our Formlabs SLA printer. Will the part be subject to load and if so how much?

 

[njmr2fan]

Its less structural and more a stabilizing part for the intersection of the piping. If they roll the thing over they'll all snap, every single one of them. I believe they just tidy up the connection and feed the bolt straight from the outside of the pipe to the inner welded nut inside the connecting pipe. If they were longer, and the pipes they connected to were stronger, then I would say that they added structural integrity.

 

[njmr2fan]

Maybe this will help for now. The top "roll bars" are made of thin wall 7/8" OD tubing. It connects to the frame in about 6 places. That's where all these plastic saddle washer tubes are used. The real connection between the pipes is a grade 10.9 M8x1.25 bolt.

 

[2kwik4u]

If it's cosmetic then a FormLabs part will do you fine. If it's structural at any level you'll want to move to a better quality parts. I've worked with SLA, and FDM machines quite a bit at my last job. We were building Aerospace components and needed to iterate through a design quickly, as well as create "non-traditional" geometries that can't be machined in a mill/lathe (small internal passages, etc). Spent a LOT of time both designing and creating those parts.

https://www.protolabs.com/
https://www.3dsystems.com/quickparts
https://www.plethora.com/
https://www.xometry.com/

Any of those places will take your model and quote you a single piece CNC'd part. Probably best for anything structural on the roll cage of your boys go cart. If it's just decorative, or shielding from hardware, then a traditional (FDM) style part will probably work, and the other guys links above will get you there.

I've been talking about getting a 3D printer for awhile for the house, but haven't pulled the trigger yet. Just can't quite justify the time/money expense for something I wouldn't use that often.

 

[RedBarron55]

Buy a piece of PVC pipe the OD you need and drill it apart with a hole saw the diameter of the tube you are connecting to and then fill with JB Weld to gain strength.
You could mold a bolt in it to provide bolting or drill a hole after the JB weld cures.
You could also mold in a short piece of steel tubing that you could thread internally if you wanted.

 

[haknslash]

I wouldn’t say a Formlabs SLA printer is only good for cosmetic parts. It all depends on the material and where the stresses will be applied as well as orientation settings in the software. I’ve used the Form1+ for many prototype parts over the years. It’s not going to be as strong as printing carbon fiber and nylon like from a Markforged printer but it doesn’t sound like this part sees a lot of force. If it did it wouldn’t be made of plastic to begin with and if the roll cage did rely on plastic components then you have bigger issues to worry about lol.

Here’s some videos where I test standard resins with their “tough” resin which incorporates some elastic properties before breaking. It’s not as brittle or hard as other resins.

 

[0627Devildog]

I love this freaking forum. . . . . That is all.

 

[njmr2fan]

@0627Devildog , I have to agree. The stuff I learn here goes way beyond boating. At times I feel like Jetboaters.net is a "Life forum" where we all just happen to have 1 of the same hobbies!

 

[2kwik4u]

I wouldn’t say a Formlabs SLA printer is only good for cosmetic parts. It all depends on the material and where the stresses will be applied as well as orientation settings in the software. I’ve used the Form1+ for many prototype parts over the years. It’s not going to be as strong as printing carbon fiber and nylon like from a Markforged printer but it doesn’t sound like this part sees a lot of force. If it did it wouldn’t be made of plastic to begin with and if the roll cage did rely on plastic components then you have bigger issues to worry about lol.

Here’s some videos where I test standard resins with their “tough” resin which incorporates some elastic properties before breaking. It’s not as brittle or hard as other resins.

They must have changed the formulation and process a bit since I used them (about a year ago now). I was using a Form 1+, and most of our parts were made with the standard clear resin. They were VERY brittle parts. Every time, without fail we would break one or two of them, often just getting them off the machine. We had to be super careful putting tapped holes in them as well, as that would typically create stress risers near the edge, and chip the surface the hole went through, even when in the middle of the part.

Here are some Form1 parts I made about 3 years ago. These held up well, but you can see the sections are really thick and it used a LOT of resin to make. The clear bottle has some internal channels that fluid was pumped through, and you can see how the peristaltic pump on the back interfaced between the bottle and the stand. That portion of the design held up well, the small passages were nicely done as well, but some of the other areas showed cracking after limited use and had to be reprinted with revised geometry.



We never really got into optimizing the printing setup though, as typically the projects had enough budget to go to a higher end printer (Protolabs, 3dSsytems, etc) once we proved the concept would work. Their printers had much better resolution, as well as mechanical properties.

 

[haknslash]

Yes the standard material is a harder, more brittle material. I typically only use it for light use and proof of concept of the part to pass it along to departments for visual aid. They love the clear printed parts lol.

I use the Tough material anytime I’m going to need mechanical performance from the printed part. I print my parts with holes and threads already made do that I don’t risk breaking them in the machine shop. I’m also trying to acquire a Markforged Mark 2 printer so that we can make more robust mechanical parts using their Onyx (nylon and micro carbon fiber) material along with their other fiberglass, Kevlar and carbon fiber materials. Not a bad price at all on the MarkForged these days and the test prints we’ve had made with Onyx were incredibly strong!!! I bought the Form 1+ when they came out and it’s been working great for us considering the desktop price and resolution you get from an SLA printer. I tried to get us an industrial level / professional Objet or Stratysis printer a few years ago but I could never get upper brass to commit to six figures at the time.

 

[chess]

if you want a 3d capitals logo just tell me @veedubtek and I can send one free of charge

 

[haknslash]

It’s been a busy week but finally getting time to print the parts for @njmr2fan . Should be done with them in a few hours and then I’ll ship them tomorrow.

 

[2kwik4u]

Inventor user eh?

I'm currently sitting in software training for NASTRAN IN-CAD.......we're evaluating it as an alternative to ANSYS.....so far.....meh.

 

[Beachbummer]

That was a resin print? Interesting....

 

[haknslash]

Parts out of the printer with their support structure based still intact. I have not dipped them in IPA yet to rinse tinge excess resin off them so that’s why they look like they have slime lol. I leave those attached until I’m finished with UV post curing.