Can a 3d printer make this part?

[hdtvjeff]

hi,

Please look at the photo, there are two plastic pulleys from a 45 year old cassette deck.

Can a 3d printer make those pulleys?

Thanks !

[curious aardvark]

yes, easily :-)

[hdtvjeff]

Thank you, Would the quality be good? Also, can you recommend a scanner (affordable) to scan parts like these?

[hdtvjeff]

This is the printer I just got, have not even unboxed it yet; just looking for your recommendation for a scanner

[curious aardvark]

forget a scanner - learn to use digital calipers and openscad: http://www.openscad.org/

the only low budget scanners currently worth their salt are the scan-in-a-box: https://www.scaninabox.com/
and the einscan scanner: https://www.einscan.com/

But you will find that not only is it much quicker to measure and model a part from scratch, it's also a LOT more accurate.
Unless you've got $10,000 to spare - scanners just aren't as good as learning how to design parts from scratch. And it's easier than you think.

[curious aardvark]

forget a scanner - learn to use digital calipers and openscad: http://www.openscad.org/

the only low budget scanners currently worth their salt are the scan-in-a-box: https://www.scaninabox.com/
and the einscan scanner: https://www.einscan.com/
Yes that is low budget for scanners :-)

But you will find that not only is it much quicker to measure and model a part from scratch, it's also a LOT more accurate.
Unless you've got $10,000 to spare - scanners just aren't as good as learning how to design parts from scratch. And it's easier than you think.

[hdtvjeff]

Wow!

Are you saying I can make those pulleys without a scanner if I master the methods you mentioned?

Does a digital caliper take into account slight curves and rounded corners too?

As a newbie we would be talking a long time?

[fred_dot_u]

Curious Aardvark has the right idea. The amount of time involved to learn a scanning program and hardware would enable you to become a genius in so many different CAD programs. Like CA, I endorse the use of OpenSCAD, especially for something as straightforward as the pulleys you desire to duplicate.

Additionally, you'll find good support here and on the OpenSCAD forum for your project. Make a couple attempts and post your results if you don't get what you seek.

Consider especially to use parametric assignments for your build. That is, don't use:

cylinder(h = 10, d = 20);

Use instead:

center_boss_h = 10:
pulley_groove_d = 20;

cylinder(h = center_boss_h, d = pulley_groove_d);

The above method will allow you to make one change in the assignments and have the effects travel through your model construction.

[hdtvjeff]

That looks like programming; is using a 3d scanner easier in that respect?

[fred_dot_u]

Yeah, it does look like programming, but it's far easier than it looks. Using a 3D scanner means a good bit more work. I've had experience with three different versions of 3D scanners and the ones that might give you the parameters you need for a duplicate part are complex and in some cases, very finicky or very touchy in getting good results.

If you're not comfortable with a text based model creator, you may want to investigate your options with a GUI type of program. For something resembling parametric modeling, OnShape (free for hobbyists) is an easy learn. More challenging and of course, more capable would be Fusion 360 (free for hobbyists). I've had reasonable experience with both and OnShape is by far easier to learn for your objective.

Less useful for your model is a free, web-based GUI CAD program called TinkerCad. If you are careful to monitor the dimensions of the parts placement, you may get away with creating your somewhat-simple model in TinkerCad.

Stay away from SketchUp, as it is known to create non-printable models. There are work-arounds, plug-ins and perhaps some built-in 3D model utilities for SketchUp, but why go in that direction when the above programs are superior for your purpose.