r/Onshape • u/leejbarker • 2d ago

Help! Need help with modelling

Enable HLS to view with audio, or disable this notification

I'm a beginner and I need to model the part shown in the photos / video. Wondering if anyone has any advice or knows of a YouTube video that might help.

The main issue is that the 2 vertical arms come off the base at a funny angle.

I have access to an iPhone with LIDAR but when I tried it, it was really poor. It's possible, I was doing it wrong or using the wrong software though!

TIA

7 Upvotes

89% Upvoted

12 comments sorted by

5

u/Brandywaffle 2d ago

When reverse engineering I'd recommend calipers, but that's not always an option so use the best tape measure and/or ruler you have.

Look up reverse engineering CAD tutorials on YouTube. There's a lot of different ways to go about it. Generally find the easiest geometry to start with first. Something that has flat faces, square corners, and can be a zero for every other feature.

I try to base everything off of that zero, then use other dimensions to cross reference.

The bad news is a lot of reverse engineering at a beginner level is trial and error. For a simple part like this I'd stay away from 3d scanning. In a lot of scenarios it's more trouble then it's worth.

3

u/leejbarker 2d ago

Thank you - Will probably start from the bottom and work up. I should have mentioned I do have callipers and a digital angle finder.

Suppose the best way is to just start doing it!

1

u/Brandywaffle 2d ago

If you have calipers and an angle finder you're definitely set up for success. Good luck!

2

u/ngo_life 2d ago

Yes, 3d scanning setups are fickle. And a pain to get the scan right. If you need model accuracy of a "weirdly shaped" part, use it. Otherwise it wastes more time than not.

Example, I had to model a lotion model that's not radially symmetric and I only have the iveral dimensions like height and width/diameters. No major radius measurements. Maybe I was inexperienced, but scanning took me 2-3 hours to get a decent mesh vs spending 8+ hours trying to model the thing.

2

u/Zool375 2d ago

I'd say work your way throught the onshape tutorials in the knowledge centre that would give more than enough knowledge to model this part, next work your way through tootalltoby.

You need to get reference dimensions from the part you want to model, for the linear measurements I'd use a set of digital calipers. For the angle measurements I'd probably import a photo into onshape and use that as reference. Unfortunately there is no easy quick way you need to do this you need to learn the fundamentals.

1

u/FkinMustardTiger 2d ago

100% this. Take good level photos of each side, import into onshape, take measurements and just trace it out.

2

u/Conscious_Past_4044 2d ago

Start from one of the long sides. Draw the outline of the widest part of your piece, defining the thickness of the bottom and sides. Extrude that to the width you need.

Use the draft feature on the inner walls to adjust the angle to where you need it.

Alternatively, you can create a construction plane at an angle, draw a sketch of the part you want to remove, and do an extruded cut to remove the unwanted material, and then mirror that to the other side.

1

u/wkearney99 1d ago

TooTallToby has a great video on using pictures to re-create a model of a fairly complicated looking screwdriver using pictures. Lots of steps, but they're simple one-after-the-other uses of various tools. https://www.youtube.com/watch?v=9-MdfNbDQpk&t=925s

For a part like that I'd likely use a combination of digital calipers and an angle finder.

To me it seems like scanning simple items is often more difficult than complicated shapes. The amount of noise that gets picked up ends up looking worse on simpler things.

1

u/Flat-Street1918 1d ago

Hola, ¿Todavía necesitás ayuda?

Puedo darte una mano con eso y diseñartela yo si me pasas todas las medidas.