It can be made up to some degree in diameter. But you have plenty more space for a bigger motor. That’s a pretty small motor.
the benefit of doing it with the sk3 original motor from the es thread is it has bearings supporting on both sides of the can while almost every other outrunner isn’t. you could just have it float out there unsupported and hope it doesn’t hit anything and get dented and done. or press in a bearing housing has been done a couple times ive seen
Well i’m currently looking at custom bldc motor makers i’m going to try and get some quotes, and i’m also looking at very high end RC motors that would blow the sk3 out of the water, and I think I’ve found some really good options there. My main thing is I want top quality, and I don’t think that those motors at about $90 are that high in quality, which just makes me all the more irritated because I was so heart set on getting a 4WD setup from Carvon cause I thought they were built from scratch and high quality. I understand that just cause there repurposed airplane motors doesn’t mean there bad, but at the cost they are just for one, not even figuring bulk, I just don’t see how the motors on their own are selling for $600 and $700… If I can get some custom ones made that have as much torque and top speed and are top quality, thats definitely the way i’m going to go, and who knows, if there a good enough price, i’ll maybe try and sell em. Well see…
There is a lot of CNC machining involved. CNC machining is expensive and takes a lot of time. It’s not just slapping parts together with crazy glue
1 Like
I realize that, but its just the truck hanger. That can’t cost more than… I dunno $50 done in bulk. Maybe $75 max?
Well I suspect I’ll find out soon enough what these kinds of costs are, I’m in the beginning talks with companies about building my own high end, purpose built motors, and possibly a finished board… well see. I’ve always wanted to do a kickstarter. I hope I hear some good news from one of the many companies i’ve contacted.
I already see a design fault using fully threaded axles. You’ll have to use partially for just tightening.
why don’t you like fully threaded axles?!
Have you ever had anything machined???
CNC trucks cost between $100-200 each in bulk. The cost of materials alone for CNC trucks is probably $50-75, plus machine time and remember technicians are also not free.
Throw in a pair of $90 motors, the cost of machining truck adapters, wheel adapters and other random parts. The cost is easily $400, them being sold at $600 for duals is not that crazy.
1 Like
I have no problem using fully thread axles. However, it’s an engineering thing you won’t ever see a dynamic load use threaded axles for the wheels. Thre real technical answers are you need to take into account the material’s ultimate tensile strength and yield strength under dynamic and static loads. Shear strength is more critical in what you are doing. There isn’t a specific value for this, but a simple calculation gives an approximation versus FEA analysis. There’s a few post of axles sheering off from using hub motors. I can’t remember who posted them.
First off, I never said anything about fully threaded axles so I’m confused where you got that assumption, and secondly, yes they cost that much, but for the whole truck or truck set! This is just one part of the hanger. It’s not even the whole thing, just the very center. The rest is the 12mm axle. That’s what I’ve read it only comes with, if I’m wrong, then ok a full truck is worth $100, but if it’s just that part of the hanger, no way.
Still trying to figure out where fully threaded axles ever came up…? I certainly wouldn’t think to use them in the first place.
$31 (plus shipping) for a 1x3x3 in block of 5052-H32 block of aluminum
$8 for 12 mm Shaft
And all the time machining the aluminum, making keyways, and keys. Tons of time…
So at least 100 bux for just a hanger and this is only if everything goes to plan… Which it won’t!
Also, $90 per motor is what we pay. I’m sure when your ordering in bulk that goes down to like $75 or so. So 2*$75 (motors) + ($50-$75, hanger) =, $200-$225 plus a bit for labor, though these are coming from China, so that labor is way less than what we’re used to. I’d be extremely surprised if they were over $300 a set, so yes I do think that $600-$700(the XL is just the 6374 sk3 at 149kv rewound to wye termination dropping it to 85kv but it’s only a few extra dollars at cost per unit for us, again, not at bulk, so that price is even more upsetting) has got to be a considerable markup. Similar to battery packs that cost about $300 in parts, but are sold for 1.5x more at like $750 or more. I’m all for making a profit when work is done and time is spent and the parts cost money, but let’s be reasonable.
You mentioned you’d need to save a while to buy a pair of Carvons yet you are speaking of buying in bulk. How can u be in a poaotion to buy in bulk if buying a single pair of Carvons requires savings?
1 Like
So your saying almost every hanger that is CNC’d has an issue where it doesn’t go to plan? That’s insane! If that was actually happening, whoever is in charge of the CNC work would be fired if there was that kind of constant error. Also, isn’t it possible to program a CNC to do shapes without constant supervision? I may be wrong in that thought, but it seems that there are many programs that can run a 3-d schematic.
That was if I came to some agreement with a company to manufacture them I’d try to do a Kickstarter campaign.
1 Like
Assuming they wouldn’t do just 4, but would have a minimum order quantity.
1 Like
Also I feel like this point has gotten lost, but I still think Carvon’s are great, but after learning more about them I just have an issue with the pricing. I feel for that kind of money we should be getting the very highest in quality motor, not the repurposed sk3, which though is still good, I just don’t see it being reasonable for a pair of them bought in bulk along with the hanger which I’m sure is high quality (though I’ve heard multiple issues of the axle snapping) to cost so much. That’s all…
If you have a cnc machine I say go for it
Yeah that’s exactly what I was saying
On other note i wasn’t talking amount cncing. But a manual mill. I gave my first hanger a shot for my diy direct drives about a month ago. Learned a lot and am going to try again. If I had the money to cnc I would but still that would take multiple attempts and time to get right.
1 Like
Fair enough, but wouldn’t the difference between a MANUAL mill vs a CNC running some auto cad type program produce much different results consistently speaking. I mean one is manual, the other is running off a program which I’m sure they’ve worked out to produce exactly the same part in the exact specifications they want each time…