SaperPL's Custom Parts

[SaperPL]

I know this is a bit of heresy, but I've seen some people using various custom parts like tyres, rims, pneumatic actuators etc.

This is my attempt at shrinking front axle suspension:

I started by shrinking 15459/31794 and 2739a

 

And then I made a liftarm with teeth to replace functionality of 6574 so it doesn't need to lay on system bricks:

 

I need to figure out some kind of neat rear axle to match this, but it feels like I won't be able to have independent rear suspension without making some over the board custom elements and I wouldn't want to go that far.

The steering arm and liftarm with gear rack can be found here: https://grabcad.com/library/lego-technic-compatible-front-axle-suspension-parts-1 (I'll try to upload it to thingiverse, someone noted it already that it's better because you don't need to log in to download).

I'm re-doing the rod as I used someone else's design from here: https://www.thingiverse.com/thing:3210100 and the connection on the ball is pretty loose.

Hopefully this is interesting :)

Edited July 31, 2021 by SaperPL
Consolidating topics on 3D printed parts

[efferman]

i like the steering rack

[Jurss]

Steering rack ir really good engineered. I like it.

But here we also see one main issue with these narrow axles - they are almost impossible to firmly connect to chassis. There then should be also some cusom, frame type part to do this.

[1974]

16 hours ago, SaperPL said:

And then I made a liftarm with teeth to replace functionality of 6574 so it doesn't need to lay on system bricks:

 

6574 does not need system bricks to work, just a flat surface

[SaperPL]

1 hour ago, 1974 said:

6574 does not need system bricks to work, just a flat surface

This is true when you are using it with longer rods, but here it means when putting this on top of a liftarm, the bals joints would be vertically offset from the plane in between the attachment points of steering arms, so this would distort the steering as being lower would mean the steering links would make wheels come inward when suspension is released and outward when suspension is pressed.

The second issue is that 6574 or even this piece would freely move on a forward axis, so while 6574 used with longer rods is okay to move a bit front to back if secured a bit from the front, for a small setup like there's no place in front of it to secure it with something blocking it off.

17 hours ago, efferman said:

i like the steering rack

 

2 hours ago, Jurss said:

Steering rack ir really good engineered. I like it.

 

Thanks!

2 hours ago, Jurss said:

 But here we also see one main issue with these narrow axles - they are almost impossible to firmly connect to chassis. There then should be also some custom, frame type part to do this.

Actually I ran out of longer axles for this build and tried to simplify it without hiding the functionality. My previous video shows how overcomplicated it could be. Anyway there is a liftarm 3L positioned vertically where you could mount a longer one or simply you could use 7L axles instead of those 5L with stops to have more connection points. but yeah, I get that, but I got used to the fact that with those small builds, you need to sometimes reinforce the frame with the body above the steering to have a solid construction.

If you have any ideas for some custom parts, you can throw those at me, I can try to figure those out for printing. Also you can use Studio's part designer to put together pieces of existing parts by importing pieces from library, shaving them off with eraser from what you don't need and putting them together into a single new part. Using eraser on some technic parts is glitchy, but you can make a point or show what you mean better with those at least.

[SaperPL]

I made a quick build from some leftovers to test it:

 

I have also created thingiverse account so you can download the custom part files to print without grabcad account.

You can find the source files from Solidworks and STL files for printing here: https://www.thingiverse.com/thing:4800409

[NoEXIST]

Very interesting parts! 

But if I did them, I would make the arms and links 1 stud longer for comfortable using in 42093 scale.

[SaperPL]

1 minute ago, NoEXIST said:

Very interesting parts! 

But if I did them, I would make the arms and links 1 stud longer for comfortable using in 42093 scale.

Thanks!

I did it this way because that's generally the scale I'm used to with my small models, but yeah, it would be cool to have this part in different sizes.

[SaperPL]

I did another custom 3d printed piece:

This is a small scale, front wheel drive GoKart build made to show off a new custom 3d printed piece that I made.

 know this is a bit weird construction for a GoKart, but it's meant to be a simple build showing off the steering hub. Also 4WD wasn't really an option without a differential between the front and rear axles as there's slight difference between front and rear axles rotation when turning that causes resistance when doing so.

You can download the STL file for print here: https://www.thingiverse.com/thing:4806746/files

Please note that with CV-joints instead of standard universal joint, the custom hub could have an axle hole, would hold the wheel more firmly and be a bit more universal. I will revisit this idea when I get some CV joints for testing.

[SaperPL]

I've got some CV-joints, but I don't really like their limited bend angle so I'm sticking to universal joints.

I've made an improved version of my the custom 3d printed hub to be used with bigger wheels:

In previous design the wheel axle was held just by universal joint which wasn't perfect. For bigger wheels, I had to improve it by adding some material to hold the axle properly. Without the rim tightly enclosing the hub, the bigger wheel will wobble a lot on the old hub.

You can download the STL file for print here: https://www.thingiverse.com/thing:4859345/files

[SaperPL]

 

I'm consolidating my 3D printing topics in this one to keep track of it. Future releases will go into this one.

On 5/19/2021 at 5:42 PM, SaperPL said:

You can download the STL files for print here: https://www.thingiverse.com/thing:4863373

On 7/23/2021 at 8:39 PM, SaperPL said:

I really don't like how Lego is making medium sized Technic rims, so I tried designing my own rim.

STL files for printing: https://www.thingiverse.com/thing:4915002 (still not finalised design though)

 

 

On 7/26/2021 at 9:04 AM, SaperPL said:

I printed the arms yesterday but it took me some time to make the video:

Files for printing, including new version of the wheels: https://www.thingiverse.com/thing:4916659

There are also studio files with sockets setup for testing in studio.

If you have any ideas on parts that could be designed or simply have a problem that could be solved with custom part, let me know here, I might be interested in designing it.

[SaperPL]

STL files for printing:

https://www.thingiverse.com/thing:5102079

[2GodBDGlory]

That looks quite useful! I suppose it would be possible to make a similar one that would have the axle on one side and a standard Lego half with the axle hole on the other?

[SaperPL]

6 minutes ago, 2GodBDGlory said:

That looks quite useful! I suppose it would be possible to make a similar one that would have the axle on one side and a standard Lego half with the axle hole on the other?

Sure, but you're kind of getting into CV-joint territory with this, except CV joint has terrible angle of operation.

[Slinger]

Maybe it's wrong to revive this old thread, but I need to ask you something: how do you make such smooth prints?

I find your designs really inspiring and would love to try doing these kinds of parts myself. From what I've read you're printing with PLA. What kind of processing do you do afterwards? Sandpaper?

[SaperPL]

7 minutes ago, Slinger said:

Maybe it's wrong to revive this old thread, but I need to ask you something: how do you make such smooth prints?

I find your designs really inspiring and would love to try doing these kinds of parts myself. From what I've read you're printing with PLA. What kind of processing do you do afterwards? Sandpaper?

I print them at pedantic resolution meaning 0.12mm layer thickness. Apart from that it's just orienting parts for printing in a way that is optimal for print, but it's case by case.

[Slinger]

Oh, wow! That is really motivating. I didn't think 3D printing had reached this level of precision. You are using an Ender 3 v2, right?

Thanks a lot for replying! :)

[SaperPL]

4 minutes ago, Slinger said:

Oh, wow! That is really motivating. I didn't think 3D printing had reached this level of precision. You are using an Ender 3 v2, right?

Yes, it's that one, it's pretty stock printer, but I've got a BL touch sensor added to it now. The print takes more time when you make the precision like this, but if you're making small parts that are critical for some mechanisms that you make just few of them, then it's worth it taking an hour or two to print those.

I think that there is a newer version of Ender that has quite a lot of improvements btw

[gyenesvi]

Indeed, your prints seem to be the best quality out there that I've seen so far!

On 11/7/2021 at 6:54 PM, SaperPL said:

STL files for printing:

https://www.thingiverse.com/thing:5102079

That U-joint is a really handy part, I have just been wondering recently how good it would be if something like it existed..

On 7/31/2021 at 11:27 PM, SaperPL said:

If you have any ideas on parts that could be designed or simply have a problem that could be solved with custom part, let me know here, I might be interested in designing it.

Pity I haven't seen this before, I'd have a few ideas :) For example, the male part of the new CV joint with an axle instead of an axle hole. I believe it's not possible to make it with 2L axle, as the U-joint you did, because the ball needs a 1.5L space to articulate properly, but it would still be useful with a 1.5L axle. For example, it could be used to make a 5L double CV joint (currently 6L is the shortest possible), or a 7L sliding version coupled with the 5L sliding male part.

Here are a bunch of renders of my custom part designs in Studio Part Designer, that include some connectors for mounting the planetary hub into smaller builds, thin L-shaped liftarms/frames, etc that I find would be really useful general parts.

https://bricksafe.com/pages/gyenesvi/custom-parts

Wonder if you find some of them printable.

My latest idea was to see if the existing portal hub could be enhanced in terms of steering pivot. I believe a redesign like this would be possible (with smoother joining of curves), retaining much of the flexibility of the existing one, but allowing it to fit into deeper rims (like that of the Land Rover), and moving the pivot point of the U-joint 2 studs closer to the wheel (it would also require a narrower inner rotating piece that holds the wheel with 3 pins). I guess this is far from being easily printable :)

[SaperPL]

I'm thinking of printing a custom, medium-sized (8 teeth - between small 6 teeth and large 10 teeth) sprocket for my Sherman tank. Printing one right now, if the test print is successful, I can share the file.

Is there anything that would make sense to add to a sprocket like this? It's 1 stud wide so it's not going to obstruct anything like the smaller one but it also has those pin sockets around the axle socket, so you can potentially add something to it.