Hardened alloy steel gears
6061 is the casing
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I though that current ones are 7075? Isnāt 6061 a downgrade?
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It isnāt a flat plate so the high grade material would be a waste for sure
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Wouldnāt moon drives work?
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Hm trueā¦hm Iām trying to find the most cost-effective solution though. Was going to go for belts by idlers but then this popped up at a super competitive price.
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I donāt know Kevins specific reasoning behind his design choices.
But some metals info: Thereās not really a downgrade/upgrade scenario in metal, the same way there isnāt really a downgrade upgrade between high end battery cells. Itās a best fit to the application scenario.
7075 is harder alu, so it make sense to use in something like the belt drive mounts where ridigity is important and the majority of the mount does not require machining. The thicker multi part gearbox mount doesnāt necessarily need that level of hardness and strength since there is more material present. Compared to belt mounts the gearbox is a highly machiened part. So a softer metal cuts down on machine time and cost.
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Itās also a complex shaped part, so the geometry has faces in different directions (the vertical part is connected to the sides of the casing), resisting loads in more directions, more efficiently.
A flat plate is good for resisting in plane loads but will be comparatively weak out of plane. On a flat plate mount, that means using a stiffer material is more beneficial.
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Donāt think there would be any Alu on Alu working surfaces.
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bad ass
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One thing Iāll say is 7075 is not stiffer than 6061, but it is āstifferā in that itās harder to get it to yield when it is under bending. Stiffness in belt drives is important because rigidly supported pulleys reduce skipping. Itās why bearing pulleys are good, they donāt shift around under torque
6061 is used for all the aluminum because thereās zero places where 7075 makes sense. The gearbox casing does have a lot of material. The adapter has a fillet to reduce a stress concentration.
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isnāt this almost the definition of stiffnessā¦?
My Google fu just learnt me that 7071 has almost double the yield strength of 6061
Stiffness is stress over strain. So by that definition, 7075 and 6061 will both bend the same amount under the same load, but the 7075 is more likely to bounce back to its regular shape.
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Not a chance, those wheels are too big to be ran on such a small gear drive. Bergs are the biggest wheel I allowed for. These are made for urethane mainly. One size does not fit ALL, just some.
Perfect for a street carver. Sad they came a couple months late for my metal build with @Boardnamics 220s as I originally wanted GDs on them, but not available in the market at the moment x that hanger. Well, at least we brought another alternative with the first @IDEA mounts for the BN220s. The more the better, no? Variety makes them popular.
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Why dont they fit tb 218ās. Could I sand alittle off of the 218ās. I just got done taking all the black paint off and hours polishing them.
Just buy his hangers, you wonāt regret it. My TB218 ones bent anyway lol
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My kids are all under 100lbs
Fair, but it doesnāt really make sense to try and make these support an inferior hanger with wider tolerances
Probably better off going belt drive for those builds haha or sell your stuff and upgrade to these for almost the same price lmao
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Dude! I just spent plenty more than this for my little build on whoosh mounts, BN wheel pulleys and motor pullies/idler.
Then Kevin come with these in the āI cant afford Not to buy theseā category.
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