Marui Big Bear tires - let's CAD :)

[Dadio]

Very annoying but it just happens to every one , you just don't need it near the end of a long print .

[silvertriple]

Very annoying but it just happens to every one , you just don't need it near the end of a long print .

yeah... it buggs me somehow. I believe I made a mistake with the filament : it remained on the printer since last time (before I went to vacations). The start of the print was perfect, layer adhesion was perfect, and at some point bubbles satrted to appear at each layer end or start, and tick tick at some point. As I was next to the printer I saw the nozzle was no longer delivering anything... I believe it may be a retractation issue. I may go for a temp tower and a retractation tower to check the right settings once I have unclogged the nozzle before restarting a print...

[Dadio]

I think it depends on the filament , I've had some filaments become brittle toward the end of the roll were it's a smaller radious and has to straighten to go into the printer , I've had perfect prints with this sort of filament but returned the next day to get a failed print because the filament has broken inside the Bowden tube , my printers are both direct drive but I use a reverse Bowden to the spool.

[silvertriple]

Printer is back online, and tests can resume... I reset all cura parameters to default and set a temp tower to reconfirm the temperature... Which is exactly what was set before. The retraction is now different and bubbles no more ( maybe the issue was coming from this.

Today's printing test has two objectives: confirm lettering would work. I'm printing this test in 0.2mm per layer. There should be a way to do better than this... And it should work.


Next objective is to make sure spikes can print properly as there is bridges and no support, and this will be the difficulty.

The first row of spikes seems perfect, even on the bridged part...


on the second row the overhangs are harder... A few degree of angle can change a lot. That being said: I've not done a single cooling optimisation yet on the printer and all is set to default. I have in mind he fact I want to change the extruder by a direct drive extruder and improve the cooling... But for the first test, it is not really bad.

I will print the full mould over the week-end. This is good progress and also good insights for the Big Bear mould which should be much easier to print than this one...

[Dadio]

That's a nice test print , are you going to try to make a tire with it or go straight to a higher resolution ? , you would be able to go down to 0.08mm with a stock Ender and if you really want the details like writing and spikes to look as good as possible then maybe try a 0.2mm nozzle , the print will take forever but without going to resin prints it will be as good as you can get , the other thing to do is print slow , all adds time but the finish will be better for it . Best of luck I can't wait to see how you get on , it's a real rabbit hole your diving down

[silvertriple]

Yeah, tires are kind of a black hole for me right now... I believe to get better finish, I'll have to go for a resin printer... That would be much better. I have a plan for one at some point, but it is still months from now.

In the meantime, the plan is to do testing with those prints at this stage. I tsill have some to get some furnitures : a vacuum chamber (and if possible one I can invert to pressure it to 2 bars or 30PSI), i need to check the vacuum pomp I have is able to cope with the chamber, need also to buy the Vytaflex 60 resin. But first there was this prints to do. This is removing quite a lot of my doubts already...

And it allowed me to check my model as well: Spikes fits in their hole, profile is right. Model is not bad


Somehow this shows me I'm on the right path

[silvertriple]

Launched another test after the full mould is printed, It did fail at 90%... Nozzle cogged again? No, this time it's out of filament, and the so called filament end sensor (aka microswitch) failed to detect the end of the filament... I need to find a better solution for this sensor... And resupply PLA as I just finished the last roll...
(The good thing, because there is a good thing and I like to think positive is that my printer prints overhangs better than I thought...)

[BillKrueger]

Any update on this project?

[silvertriple]

Any update on this project?

I'm still having intention to do something about this... Had to put this in sleep state as I need to order some materials and tooling to do the tests before confirming it can be done the way I think (to me this is a condition to put something on Thingiverse). I have no way to print money unfortunately and I have to prioritise base on availability and familial planning... And let's be clear : I have about 112 cars where I have the tire model and the need for real tires, and alternatives are not really suitable to me, os I have to do something, and if I succeed to do for one tire, I should be able to do the same for many...

[iiokurud]

Hi, can you send the files for the big bear tire mold to Neal at MCI? He will make the tires, I am sending him one brand new wheel right now, he either needs a perfect tire or this 3d file. Let me know and thank you.

[silvertriple]

Hi, can you send the files for the big bear tire mold to Neal at MCI? He will make the tires, I am sending him one brand new wheel right now, he either needs a perfect tire or this 3d file. Let me know and thank you.

You may tell MCI to contact me if he has any interest on this. So far, I've shared files on Thingiverse and Cults3D, and if I decide to share those files this will be on a non commercial license, which means that the only usage that can be made of those files is non commercial and for the sole purpose of the guys downloading it. And this would be the same if I decide to sell the files...

And that would be also true for MCI-Racing, unless he contacts me and I decide otherwise. I'm ready to help, but I do not want to have people doing business based on my work on my back.

And as matter of fact, I have modeled the full chassis and rims of the Big Bear and Super Wheelie as you may see in another thread... This is currently under testing, and I will decide what I do with those when I will have finished all my tests... And there is one reason I insist on the non commercial stuff : I don't sell stuff, I don't make business ofrom my hobby, but I see a lot of downloads of my files, and very very very few tips, and those don't even cover for the test prints...

[iiokurud]

Understood, thanks

[silvertriple]

Since I started the experimentation with the Flex resin printed tires, I have a big question remaining in my mind... Would it be possible to print a Big Bear tire this way...

I've opened chitubox, put the tire in (not much ways to change the orientation), added supports and looked at it:


It appears my printer's bed is way too small for this... I'll have to try the molding way...

[silvertriple]

The first product issued from this CAD thread is born...





Files are available here :
https://www.printables.com/model/478350-marui-big-bear-tire

Happy printing !

[BillKrueger]

Wow that looks amazing. Might have to pick myself up a resin printer.