Re: Marui Samurai 4WD - Another SilverTriple's journey...
Posted: Mon Apr 03, 2023 3:15 pm
Looks great , really interested in how they grip and wear , do they feel like rubber or more like soft plastic ?
They really feel like rubber... I was not expecting a result that good, actually... The 30 seconds run on a asphalt were definitely not enough to do a single trace of wear... And it grips nicely in the living room, just like proper tires, and that actually surprised me... They are soft, you can squeeze them like hotshot tires... The wear remains the question, but material cost is about 8 euros/tire, supports included (I'll get another run of that resin, to get an additional set of Samurai and Ninja tires)... And I may not have found yet the optimal way to orient the tire for the print... I'll find a time to do a proper test (and I also modify the tires so I can make sure they seat properly in the rim - as matter of fact, I checked the original set of tires I have and they have internal diameter slightly superior to the outside diameter of the rim : with 3D printed rims and tires, this is very easy to fix, actually...)...
At 8 Euros per tire it's pretty cheap too , my printer may not have a big enough bed , the angle would need to be quite steep , I may have to create a rudimentary tire dimension model to see if I could fit one tire at a time .silvertriple wrote: ↑Mon Apr 03, 2023 3:44 pmThey really feel like rubber... I was not expecting a result that good, actually... The 30 seconds run on a asphalt were definitely not enough to do a single trace of wear... And it grips nicely in the living room, just like proper tires, and that actually surprised me... They are soft, you can squeeze them like hotshot tires... The wear remains the question, but material cost is about 8 euros/tire, supports included (I'll get another run of that resin, to get an additional set of Samurai and Ninja tires)... And I may not have found yet the optimal way to orient the tire for the print... I'll find a time to do a proper test (and I also modify the tires so I can make sure they seat properly in the rim - as matter of fact, I checked the original set of tires I have and they have internal diameter slightly superior to the outside diameter of the rim : with 3D printed rims and tires, this is very easy to fix, actually...)...
I can see you are quite tempted by the experience already![]()
Thinking about it I can just hold a tire up to the bed , looks like your printing at a 25° to 30° angle , pretty sure I'd be at 60° to 70° , at that angle it would need a lot of internal support and plenty on the treaded surface , still might be worth a try .silvertriple wrote: ↑Tue Apr 04, 2023 2:41 am I succeed to put 2 tires on the 7.6 inches of the printer screen in my case... You have to use heavy supports, and the get the tire tilted in any case. And you have to include at least a hole to avoid the suction cup effect...
if you want to know more abut the possibility you may head to thingiverse and download the tires of the Nichimo Spirit FF or the Hirobo Bearcat, and see if it enters in the bed, they are more or less the same size Samurai rear tires are OD 840x400 and fronts are OD 800x320 (it's written on it). A 2.2" standard size rear tire is about OD 880x360, I think... That may also give you some indications about the possibility to put it in the bed of your printer...
I don't have anything to be able to assess this... and it would require to get a perfect print, cleaned properly before curing (a two step bath of IPA is advised - I had only one during those first experimentations), plus removal of support being done properly (I clearly rushed this as I was not having proper tooling - I took them and removed them without any tools, just by traction)... The result is promising, but let's be clear, there is lot of post processing involved beside the printing... At least for my usage, balance won't impact (vintage fun runs more than race runs, actually
I'm not sure it is that important. I just tried with a Lipo 2S at storage tension, full throttle : no visible shake... I'm not saying there is none, but it's not visible... And the rear are from my first prints, so with the visible deformation from the suction cup effect...Frankentruck wrote: ↑Tue Apr 04, 2023 9:37 am I'm mostly curious if the wheels shake a lot if you hold it at full throttle. I can appreciate all the post processing needed and how difficult it probably is to end up with a good final result.
If your running printed wheels as well there's more potential for balance problems , I got obsessed for a while designing and 3d printing spinning tops with turbines in them , looked like UFO's , idea being that the turbine would draw air in the top and out the bottom to give an air cushion underneath to make them spin very flat and stay flat till they virtually stopped , anyway long story but FDM printing rarely gave good balance because the slicer will align the layer shift point to the least visible position usually causing a heavy spot , it's worst on cylindrical objects as it will inevitably do a circle and change layer at the same point repeatedly , to avoid this is fairly easy as most slicers have a setting to randomise the layer shift point . This effect does not exist in resin printing as the whole layer is printed simultaneously .silvertriple wrote: ↑Tue Apr 04, 2023 12:02 pmI'm not sure it is that important. I just tried with a Lipo 2S at storage tension, full throttle : no visible shake... I'm not saying there is none, but it's not visible... And the rear are from my first prints, so with the visible deformation from the suction cup effect...Frankentruck wrote: ↑Tue Apr 04, 2023 9:37 am I'm mostly curious if the wheels shake a lot if you hold it at full throttle. I can appreciate all the post processing needed and how difficult it probably is to end up with a good final result.
Edit : beside the fact it is not visible, I believe there is other things impacting more the behavior of a car than this...
I always use random for the seam, specifically for the rims...Dadio wrote: ↑Tue Apr 04, 2023 1:29 pm If your running printed wheels as well there's more potential for balance problems , I got obsessed for a while designing and 3d printing spinning tops with turbines in them , looked like UFO's , idea being that the turbine would draw air in the top and out the bottom to give an air cushion underneath to make them spin very flat and stay flat till they virtually stopped , anyway long story but FDM printing rarely gave good balance because the slicer will align the layer shift point to the least visible position usually causing a heavy spot , it's worst on cylindrical objects as it will inevitably do a circle and change layer at the same point repeatedly , to avoid this is fairly easy as most slicers have a setting to randomise the layer shift point . This effect does not exist in resin printing as the whole layer is printed simultaneously .
I was sure you would but it's worth saying for anybody else reading this as its just useful information .silvertriple wrote: ↑Tue Apr 04, 2023 2:24 pmI always use random for the seam, specifically for the rims...Dadio wrote: ↑Tue Apr 04, 2023 1:29 pm If your running printed wheels as well there's more potential for balance problems , I got obsessed for a while designing and 3d printing spinning tops with turbines in them , looked like UFO's , idea being that the turbine would draw air in the top and out the bottom to give an air cushion underneath to make them spin very flat and stay flat till they virtually stopped , anyway long story but FDM printing rarely gave good balance because the slicer will align the layer shift point to the least visible position usually causing a heavy spot , it's worst on cylindrical objects as it will inevitably do a circle and change layer at the same point repeatedly , to avoid this is fairly easy as most slicers have a setting to randomise the layer shift point . This effect does not exist in resin printing as the whole layer is printed simultaneously .