Well SLOW far so good. The filament is actually printing, and looks to be doing so quite well.
Print head 240 C, bed 60C, print speed started at 15, and upped it to 20mm/sec. The print time is still going to be 5 hours, but we'll see what the end result looks like.
Almost 7 hours later and I am absolutely delighted. The print went fine if a little slowly but no printing hassles at all. gentlemen I am pleased to present a Diamond T tyre
The support stuff came off but put up a game fight.
the tyre is flexible, I could probably have cut the infill to 10%
So it is possible to print tyres in flexible PLA with an excellent finish, if slightly glossy. I think a slight rub down with fine sandpaper would fix that.
Top job Alwyn, you are a braver man than I, lol. I am assuming that the extruder handled the filament ok. I am also thinking that printing hollow tyres would see the job done in a couple of hours?
Hi Rob, I did consider that, but I didn't want to risk a 'floppy tyre. There is only 20% fill in the tyre so its mostly fresh air, I think printing a support structure would actually have taken longer. Anyway having proved the concept and confirmed the CR10 can handle the filament, I'm now going to search for some cheaper filament so I can experiment with print speed and other parameters.
At least we now know it's doable and produces a good result, from now on we are no longer constrained by tyre availability for our builds.
Having reviewed the print parameters there are a few ways I could have cut print time. I had set top/bottom and skin thickness to 1mm where I think .8mm would have been fine, infill was 20% which could have been 10%, and I'm pretty sure that a print speed of 20mm/second would have worked. I'll only know when I get more material and do some testing. I rea?ly just wanted to test the concept which was successful, the rest is down to fine tuning and pushing the printer and material boundaries until the print fails.
You may already be doing it, but under 'Experimental' in Cura there is an option to Hollow Out Objects. This replaces infill with support material, so uses less filament.
I have been looking at the cost of flexible filament...it's not cheap is it!
No the prices are not cheap but if you look on amazon there is a product called real filament at £24 a reel that looks reasonable and says it will work with Bowden tube. I don't think any of these materials are really flexible as in rubber-like, but they should be better than classic pla.
I discovered that the 'flexible' PLA is not flexible enough to stretch over the hub, so I had to take off the back flange, which I can always glue back on, however I think I will try the moulding process next to see if I can get a decent rubber tyre which will solve the problem. The alternative is to modufy the tyre print to create a hollow tyre which should hopefully then stretch over the hub. There's always a solution if you keep looking.