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I put a lot of efforts to make this easy to use and print, with a few modifications in the parts to remove the supports requirement during the print. At the end, I had only one part where it was still required. I included some material to be removed post print to avoid supports. I also included small bridges around the holes which required to print in air to avoid the need for support (again).


I put some printed bearings in the print plate, just in case people do not want to use ball bearings (6807RS - 35x47x7) when they print anything else than TPU.


I also tried to be as clear as possible on the requirements of 2 M3 nuts (maker's supply don't have it at this stage) before starting the print as the print is paused when the 2 nuts are to be inserted.


I actually checked it worked like a charm, the 0.4mm thickness at that position is easy to cut with a hobby knife.



Everything is now in order. The slot to fix the holder is slightly tilted so even with a full spool, it is kept horizontal.



The position of the spool is very convenient now for a direct feed from the spool.


TPU prints may start, very soon, and those parts are on makerworld.
makerworld.com/...els/800143

That was a fun project

My daughter want a phone case (she tends to abuse of them )


It's good time to start a first TPU test, with a 95A shore TPU. It's from Sunlu. It is the typical TPU you would find almost everywhere. I can print it on the X1C from the external spool holder with the Generic TPU profile without any modifications. It's not fully dry so the print is running directly from the dryer, and as matter of fact, the position from entry of the PTFE tube is not practical in this case... I applied glue on the plate to ease the realease (TPU adheres well on beds, and with PEI, removal can damage PEI coating).
The print should take about 2 hours and a quarter, I'll update later.

Print was almost flawless... I'm saying almost as the slicer is possibly a little bit optimistic on the bridge length as the volume button opening had some defects... It doesn't generate any supports there, I guess I should have paint them.


That said, the result is good once I cleaned the bridge defect.



And for those asking how I did, the stl is a plain one, I just used infill pattern with 0 bottom and top layers to get this result... And while I think about this, it may be a way to make a nice thin flexible mesh to make very scale windows

I really enter now in the TPU testing, really...

Some test with TPU 95A : infill pattern impact (there is a file were someone did exactly this on Makerworld, I decided to use it). At the end I can tell than grid, cubic or anyother relying on parallel lines are not what we want for TPU. Honeycomb infill, on the other side seem to be the perfect candidate for bumpers as it is strong in all direction, while still allowing for some flexibility. Gyroid maybe ok for tires in 95A TPU from what I could see from this test.


Based on this I proceeded in a second test which aims to approach what we would see witha tire printed in TPU 95A. I used 2 top and bottom layers, and gyroid infill  3% - 24% by 3% increment. The result is that it maybe fine without side walls, but with the sine walls, the side walls are too strong so it doesn't behave at all like a tire... So this confirms more or less what I had in mind with all my previous TPU and Foaming TPU tests.

Next in line, I have a roll of Recreus Filaflex 60A. it's not TPU but TPE. The filament is highly flexible and it is difficult to load due to the friction in the PTFE tube (no way to go thru the tube - this confirms the upper mount is absolutely required for this type of filament). At the end I did a cold pull with PETG to remove anything from the hot end before loading it, and then I loaded it from the upper mount (the shorter tube is allowing it to load, with a little bit of persuasion - I suspect that it would not have worked if I did not cold pull before.
Recreus has made a profile for the filament and it is available on makerworld. I downloaded it, and use it with my test model.

One thing I can already say while a long print is in progress is that when there is accumulation of material, this doesn't behave like the TPU : the material bonds together and it seems that it remains flexible. For tires this might be exactly what we are looking for... Anyway, first test print is in progress...

The print is over...
youtube.com/sho..._VFixwj2dM

The result is really encouraging, and this means we may have another solution than Resin to print tires, because at the end it feels like the rubber of a tire...

Prints are helping in many areas unrelated to RC... The winter is the period we do what we call "raclette" with melted cheese... There is a tool for this, and everytime I used it in the past, I complained about the nuts : in the kitchen, you rarely have a wrench at hand, and tighten nut by hand is not practical.
I augmented the tool with nut knobs...


The print is again relying on a pause to insert nuts in th knobs...
makerworld.com/...els/817791
 

I have a few tools used for modelism only, and they maybe very practical on the field. I decided to create a box for that... I include the Arrowmax drill press and some other motor more suitable for rotary sanding, and as well a small vice.


To close the lid and maintained it closed, I opted for a small mecanism relying on a printed in place knob with inserted nuts during a print pause.

The drawing is upside down, and you may note how the hole is bridged in order to avoid requirement for any supports.

And it works perfectly once the knobs are free...

I had this idea since a few months...


The Filaflex 60A is very difficult to print for this, and way too flexible for this. So this idea was put in the corner after the first attempt to print a tire halve (unsuccessful cause of some retractation issues, but enough to see that it would not work).

I decided to retry with TPE filament. I got some eSun TPE 83A. I dried it and run it from the dryer. I may have to recalibrate this filament properly and to  rework the settings completely for it, but it printed with stringing... But at least it would allow me to validate the concept...



I glued the halves using the jig to center the halves and some ca glue (thin and flex, that I use normally to glue tires on rims).





Result is a tire, which can be still optimized on the printing side. Walls are like an original Hunter tire and too thick for this filement. But it kind of work, even if on the too hard range...
I will need to find a lower shore TPE filament...

The more it goes, the more I want to open new possibilities... I took benefit of the fablab to recently experience Laser cutting and carving, and CNC machining with a big CNC router, and I cut a few fiber glass parts for RC...


It is not as difficult to set it right and to take benfit of it, and clearly, I want more possibilities... I've already mentioned the Carvera in this thread, and it looks really interesting. They got one in the fablab, I saw what they are doing with it, and it goes clearly in the direction of what I want to do with a CNC Mill. And while the Carvera with its tool changer is a bit too high in price for what I'm ready to go for, the new Carvera Air is quite similar without the tool changer, and it maybe very well what I can consider in terms of tooling. I'm considering pulling the trigger on it, as it would open quite a lot of possibilities, while for bigger requirements, I could still use the CNC router at the Fablab... I may very well have to change the tittle of this thread at some point . 

And yes, I have many ideas to use a CNC mill in mind:
- bodyshell mold (aluminium)
- tire mold (aluminium)
- gears (delrin, aluminium)
- shafts (steel)
- chassis parts (fiberglass, carbon fiber)
- ...

A CNC available at home and the tools available at the fablab should allow for quite a nice set of things : there is quite a few tool I can actually have access to at the fablab (vacforming machine, injection press, hydraulic press, laser cutting and laser carving, ...)

Chassis stand would be great.
One of my dislikes of putting something under the chassis, is the wheels hangs down.
If they pick up suspension arms so wheels sit normal in wheelarch, that would be ideal.
I`m sure you can figure something out.
Possible with slots so they will fit together without screws..