I have a quick question about the weapon assembly. The Oilite sleeve bearing y'all list in the parts is only rated for ~370 lbs at 120 rpm, but it looks like y'all are running it much faster than its rating. Is it not a bit risky to put a bunch of lateral force on a bushing that's spinning way faster than it's rated to? On a related note, how many rpm would you be willing to put on that bearing? Thanks a million for your videos! I love them all and they're super helpful. I always get excited when I see y'all have posted.
Glad to hear you like the uploads! There are a few reasons that bearing was chosen. In the previous versions of Vortex a needle roller bearing was used, but due to the nature of these bearings, they tend to have a lot of "slop" or "play" meaning the shell could wobble after a big hit causing instability. We made the decision to switch to bushings since they can have much tighter tolerances due to the lack of moving parts; that's when we tried the sleeve bearing. The main concern with sleeve bearings of this type is too much sustained load. Those ratings are meant to keep the bearing from heating up and experiencing excessive wear. When not actively hitting something, the shell experiences very little radial load, only the axial load of spinning up. While the shell may experience very large loads when hitting something, this tends to be a very quick action and doesn't generate too much heat to be a problem. The other thing is that combat robots tend to have a very low service life of parts, wear on the bearing isn't a huge concern since matches tend to be only a few minutes in length and parts tend to only be used until they are too damaged or destroyed. If this part saw use for many consecutive hours, the load ratings would be more of a concern. Overall, for this application, I've been very happy with the sleeve bearings and I'm comfortable running them at very high rpms (5000+) as long as they are checked periodically to make sure there isn't excessive friction or wear. I hope that answered your questions. Edit: One more thing. The size bearing we are using is 1/2" ID 3/4" OD x 1" Length, which is actually rated for 1000lbs at 120rpm. This is due to its larger size, so it can dissipate heat and spread the load more evenly. The cone-shaped piece that helps retain the bushing is actually just 3D printed PLA, and the bushing never got hot enough to even weaken that part.
@@BlackLightningRobotics Thank you for your detailed reply! I'm new to building so I have to reach out to learn these things. One more question: are those plastic washers under and over the shell something along the same lines? Oil-impregnated UHMW or something?
@@Mintie7 That's great! We love to hear about new people getting interested in what we do. We actually just use a combination of steel and Nylon washers. UHMW is self-lubricating and can be used with great success. We, however, chose to use regular Nylon washers because they are cheaper and much easier to get; they can often be found at local hardware stores. We figured they would be easier to get spares if the ones on the bot failed, that being said, we haven't had any fail yet.
The Phillips hardware is largely due to its availability. In the part of the US where we are located, it way easier to get Phillips than hex or other options.
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Great design brilliant full body spinner
Looks awesome! Look forward to seeing how this bot evolves. Would you be able to post a parts list sometime? That'd be amazing!
Thanks! That's definitely something we can work on! We'll let you know here if we do end up posting one.
@@BlackLightningRobotics Sounds great, thanks!
@@thegreatstapley We just posted a link to the parts list in the description. I hope that helps!
Very cool!
Probably a dumb question, but, why do you use a belt drive instead of a direct drive?
i loved it
I have a quick question about the weapon assembly. The Oilite sleeve bearing y'all list in the parts is only rated for ~370 lbs at 120 rpm, but it looks like y'all are running it much faster than its rating. Is it not a bit risky to put a bunch of lateral force on a bushing that's spinning way faster than it's rated to? On a related note, how many rpm would you be willing to put on that bearing?
Thanks a million for your videos! I love them all and they're super helpful. I always get excited when I see y'all have posted.
Glad to hear you like the uploads! There are a few reasons that bearing was chosen. In the previous versions of Vortex a needle roller bearing was used, but due to the nature of these bearings, they tend to have a lot of "slop" or "play" meaning the shell could wobble after a big hit causing instability. We made the decision to switch to bushings since they can have much tighter tolerances due to the lack of moving parts; that's when we tried the sleeve bearing. The main concern with sleeve bearings of this type is too much sustained load. Those ratings are meant to keep the bearing from heating up and experiencing excessive wear. When not actively hitting something, the shell experiences very little radial load, only the axial load of spinning up. While the shell may experience very large loads when hitting something, this tends to be a very quick action and doesn't generate too much heat to be a problem. The other thing is that combat robots tend to have a very low service life of parts, wear on the bearing isn't a huge concern since matches tend to be only a few minutes in length and parts tend to only be used until they are too damaged or destroyed. If this part saw use for many consecutive hours, the load ratings would be more of a concern. Overall, for this application, I've been very happy with the sleeve bearings and I'm comfortable running them at very high rpms (5000+) as long as they are checked periodically to make sure there isn't excessive friction or wear. I hope that answered your questions.
Edit: One more thing. The size bearing we are using is 1/2" ID 3/4" OD x 1" Length, which is actually rated for 1000lbs at 120rpm. This is due to its larger size, so it can dissipate heat and spread the load more evenly. The cone-shaped piece that helps retain the bushing is actually just 3D printed PLA, and the bushing never got hot enough to even weaken that part.
@@BlackLightningRobotics Thank you for your detailed reply! I'm new to building so I have to reach out to learn these things.
One more question: are those plastic washers under and over the shell something along the same lines? Oil-impregnated UHMW or something?
@@Mintie7 That's great! We love to hear about new people getting interested in what we do. We actually just use a combination of steel and Nylon washers. UHMW is self-lubricating and can be used with great success. We, however, chose to use regular Nylon washers because they are cheaper and much easier to get; they can often be found at local hardware stores. We figured they would be easier to get spares if the ones on the bot failed, that being said, we haven't had any fail yet.
I run a 3HP motor 6000rpm to a 4lb, 14" bar on a 15lb bot. The same 1/2" bushing survives 12-15 fights so far
How much does a beauty such as this cost to build? I love full body spinners!
For even more bigger hits make one contact point you could, to not make it unbalanced add weight from inside the shell
Full body spinners are harder to kill but they usually die due to breakdowns or heavy impact to the inside from impacts
nice
Is your motor basically running your shell 1:1 belt wise or is there a gear ratio difference?
You should REALLY consider switching away from phillips drive. The bot looks great, good luck!
The Phillips hardware is largely due to its availability. In the part of the US where we are located, it way easier to get Phillips than hex or other options.
Curious, how much does it cost to build a bot like this?
Can you make a full tutoriAl on a full body spinner or any robot
is there any way to get design or buy design?
sir i want some help......please sir help me......it's urgent can u help me?plz reply