Got a 3D printer on the way, got a design question

[JDM74]

So I'm using AutoCAD to try and design a relocated battery tray for the HPI venture. I have a question regarding stress concentrations and using fillets in the corners and such. I've done some searching and haven't found exactly what I need.

Do you guys that have done a lot of design work and printed stuff from your printer/shapeways usually put fillets on all your corners? how important is it to prevent cracking/stress concentrations, etc.

I'm a mechanical engineer by trade but not a design engineer. I do a lot of testing of heavy machinery on board Navy ships so my design engineering skills are rusty, haha. I know it is important in the 1:1 world where things are cut from a block of material, but not sure how much of that translates to and additive process such as 3D printing in the world of toy trucks. I feel like a fillet on a part that is 2 mm wide gets lost in the resolution of the printer.

[k7zpj]

Originally Posted by JDM74

So I'm using AutoCAD to try and design a relocated battery tray for the HPI venture. I have a question regarding stress concentrations and using fillets in the corners and such. I've done some searching and haven't found exactly what I need.

Do you guys that have done a lot of design work and printed stuff from your printer/shapeways usually put fillets on all your corners? how important is it to prevent cracking/stress concentrations, etc.

I'm a mechanical engineer by trade but not a design engineer. I do a lot of testing of heavy machinery on board Navy ships so my design engineering skills are rusty, haha. I know it is important in the 1:1 world where things are cut from a block of material, but not sure how much of that translates to and additive process such as 3D printing in the world of toy trucks. I feel like a fillet on a part that is 2 mm wide gets lost in the resolution of the printer.

I use fillets on the parts that I print with my 3d printer to minimize damage to the sharp edges of the print.

With the slicing software I use, you get the best results when the radius of the fillet is a multiple of the nozzle diameter. For example if you have a 0.5 nozzle then a 2mm fillet works.

[mikemcE]

Another variable is your filament choice. ABS or PETG or ????



Hang up and Drive

[Robbob]

Originally Posted by JDM74

So I'm using AutoCAD to try and design a relocated battery tray for the HPI venture. I have a question regarding stress concentrations and using fillets in the corners and such. I've done some searching and haven't found exactly what I need.

Do you guys that have done a lot of design work and printed stuff from your printer/shapeways usually put fillets on all your corners? how important is it to prevent cracking/stress concentrations, etc.

I'm a mechanical engineer by trade but not a design engineer. I do a lot of testing of heavy machinery on board Navy ships so my design engineering skills are rusty, haha. I know it is important in the 1:1 world where things are cut from a block of material, but not sure how much of that translates to and additive process such as 3D printing in the world of toy trucks. I feel like a fillet on a part that is 2 mm wide gets lost in the resolution of the printer.

How much stress is a battery tray gonna take really? Its a stationary part that just holds a lipo, my opinion would be fillets to clean up appearance.

Other then that I design my stuff as if I were making it on my machine. Fillets are for strength and appearance for me, I totally dislike sharp corners for some odd reason.

If I think it needs strength then I just increase the fill %. The outside is only as strong as the inside is my theory. Plus if you're waiting 2 hours for a job to print then waiting a little longer for more internal strength wont kill ya.

[5bites]

I say use fillets every chance you get. As was mentioned before you sometimes have to do some planning regarding nozzle size, layer height, whether supports might be necessary etc. If for any reason it makes a part look more finished.

[5bites]

I’m curious why you chose AutoCAD?

[JDM74]

Because I already have it and I know it.

[BigSki]

When I'm using solidworks for designing RC parts, I use fillets for appearance and also if it's a part that I'll use to make a 2 piece mold for making resin copies, the fillets allow for easier removal of the part from the molds.

[Robbob]

Originally Posted by JDM74

Because I already have it and I know it.

I use Autocad for everything I do thats 2D, I could never grasp the feel and controls of using it for 3D.

I installed Inventor and I love it for my printed stuff. Had to update to 2018 inventor after using 2012 for the last 3 years . I was nervous and scared because 2015 sucked for me, I didnt like the controls or interface setup at all on it. 2018 though is perfect and smooth, couple things changed as far as where to click now but very easy.

Just food for thought in case you wanna try something different.

[JDM74]

Well the printer is up and running after some annoying inaccurate user's manual. I had to chat with a tech guy so he could explain how it really works as apposed to the crappy manual. I'm printing some robot that came with the Cura software that came with the machine. I've been able to import stuff from AutoCAD and coverted it in Cura to a working file so....I guess it's time to learn...

[BigSki]

Originally Posted by JDM74

I've been able to import stuff from AutoCAD and coverted it in Cura to a working file so....I guess it's time to learn...

Your printer doesn't use a .stl file for 3D printing?

Never mind, I gargled it after I made the post. I'm not on top of the tech curve in regards to the different softwares to convert .stl files into a tool path for printing. I'm curious to see a pic of a printed part.

[Phuckstick]

No need for fillets on a battery tray. Will just take up space

Sent from my VS985 4G using Tapatalk

[5bites]

Originally Posted by Robbob

I use Autocad for everything I do thats 2D, I could never grasp the feel and controls of using it for 3D.

That’s why I asked too. 2d is ok. It’s still not as refined as I’d like it. We use mastercam at work and it has me completely spoiled. The extreme cost keeps it from being an option at home. Ive used pretty much all the free stuff. I recently tried viacad 2d/3d and it didn’t make me want to stab my laptop. It’s around $70 so I’m considering it.

[Robbob]

Originally Posted by 5bites

That’s why I asked too. 2d is ok. It’s still not as refined as I’d like it. We use mastercam at work and it has me completely spoiled. The extreme cost keeps it from being an option at home. Ive used pretty much all the free stuff. I recently tried viacad 2d/3d and it didn’t make me want to stab my laptop. It’s around $70 so I’m considering it.

Ive heard mastercam was good but never tried it .... I got lucky with Autocad and 3yr license's so I just keep that going.

[5bites]

It really probably just what a guy is used to is what is best. Tons of people talk about how great fusion 360 is. I personally hate it. It just doesn’t flow well for me. I just need to stay on it and it alone. Mastercam though is laid out well and is just simple to use. It’s also around $10k lol

[k7zpj]

Originally Posted by JDM74

Well the printer is up and running after some annoying inaccurate user's manual. I had to chat with a tech guy so he could explain how it really works as apposed to the crappy manual. I'm printing some robot that came with the Cura software that came with the machine. I've been able to import stuff from AutoCAD and coverted it in Cura to a working file so....I guess it's time to learn...

Practice make perfect with 3D printing. When I first started out I tried printing parts/models and didn't really get the results I wanted.

I got help from a pro who suggested that I practice printing the 3DBenchy model and calibration cubes until I could print them correctly without problems.

This article has information on troubleshooting 3D prints has information on the 3DBenchy model and calibration cubes.

https://all3dp.com/1/common-3d-print...rinter-issues/

This is good video on the 5 most common 3D printing mistakes.
https://youtu.be/aWg1nG2AbA8?list=PL...9toqq8EAfhiOOL

The bottom line is to practice and learn until you get really good looking prints.

[JatoTheRipper]

For those that need better engineering software AutoCAD Fusion360 is free for hobbyists. I hate it because I'm used to SolidWorks which I've used for the last 10 years. I used SolidWorks at home to design my stuff.

[5bites]

And while you’re printing benchies do them in all different colors so you have an awesome collection lol

[k7zpj]

Originally Posted by 5bites

It really probably just what a guy is used to is what is best. Tons of people talk about how great fusion 360 is. I personally hate it. It just doesn’t flow well for me. I just need to stay on it and it alone. Mastercam though is laid out well and is just simple to use. It’s also around $10k lol

Fusion 360 has a learning curve and requires you to get into a different mindset on how visualize 3D bodies. Once you really get how it works it is very powerful.

I ended up taking a classes from http://www.desktopmakes.com. That really improved my mastery of Fusion 360 and the advanced features of Fusion360.

If money wasn't an object I would use Solid Works but that is way out of my budget.

[5bites]

Originally Posted by JatoTheRipper

For those that need better engineering software AutoCAD Fusion360 is free for hobbyists. I hate it because I'm used to SolidWorks which I've used for the last 10 years. I used SolidWorks at home to design my stuff.

Glad to hear I’m not the only one.

I reeeeeally want to try solidworks but it’s not exactly cheap either. I have heard there are discounts available though.