Here is the supercharger I would start with...
- Thread starter AlexLTDLX
- Start date
MkngStffAwesome
Active member
Awesome .. are you able to try a 1-1 gearing as well ? so 1-1 ,1-2 and 1.5 for comparison ?
I just have the 1 pulley for now. I need to make sure the belt drive will hold up. Those pullies are $30 a piece here with shipping - hard to get.
I will say that if the belt drive works, this is by far the easiest way to get electric boost. The plate is 1/4" thick aluminum, the standoffs are exactly 60mm, the two mounting studs are supposed to be m10 x 1.5 (I say "supposed to be, but metric all thread and studding is impossible to get here - 3/8" NC works in a m10 hole - it's ever so slightly smaller and the threads are almost exactly the same pitch, and I had 3/8" all thread, so that's what I used.)
I will say that if the belt drive works, this is by far the easiest way to get electric boost. The plate is 1/4" thick aluminum, the standoffs are exactly 60mm, the two mounting studs are supposed to be m10 x 1.5 (I say "supposed to be, but metric all thread and studding is impossible to get here - 3/8" NC works in a m10 hole - it's ever so slightly smaller and the threads are almost exactly the same pitch, and I had 3/8" all thread, so that's what I used.)
MkngStffAwesome
Active member
Only mounting it in two places seems a bit risky to me.. but whatever it's all interesting.
So what ratio do you have right now ?
It's really solid. Plus, that's how the belt is tensioned - actually, it's identical to the way my alternator mount on the car is (I made that too; it's been trouble free for years). I'm not even slightly concerned about that - I'm more concerned about the belt itself. Also if it needs a dynamic tensioner on the slack side.
I've probably posted this before, but my Whipple was violently chucking belts until I made a custom tensioner with ball bearing pivots, an adjustable spring and a Hyabusa steering damper filled with 50 weight oil:
Here it is with a manual tensioner - actually, this is with an Eaton/Jaguar M112 (before the Whipple) - check out the slack side of the belt:
To answer your question, right now it's a 1.22:1 ratio. 22 teeth to 18 teeth.
I've probably posted this before, but my Whipple was violently chucking belts until I made a custom tensioner with ball bearing pivots, an adjustable spring and a Hyabusa steering damper filled with 50 weight oil:
Here it is with a manual tensioner - actually, this is with an Eaton/Jaguar M112 (before the Whipple) - check out the slack side of the belt:
To answer your question, right now it's a 1.22:1 ratio. 22 teeth to 18 teeth.
I did spin up the motor with the cog belt pulley on it last night to try to get the VESC's starting smoother before trying to run the blower - frankly, it performs worse than the cheap chinese ESCs so far. And I discovered that the hole in the pulley is way off - I could literally see it wobble. I put an indicator on it and it's got like .020" runout (that's like half a millimeter to you metric guys). It doesn't sound like much, but it's enough to easily see it. I don't want to risk vibrations unnecessarily, particularly hitting some harmonic that'll destroy bearings and belts, so today I'm going chuck the pulley into the lathe and bore it out with an endmill and then a reamer to 10mm and press in a new aluminum slug, and then re-bore the hole (and of course, drill and tap the 1mm wall slug thickness for the set screw).
If I can just figure out how to chuck this thing in the lathe and still keep it all centered, we'd be golden...
If I can just figure out how to chuck this thing in the lathe and still keep it all centered, we'd be golden...
WB projects
Active member
My brother use a pulley for his electric longboard and his pulley was off center like crazy too.. look like they are cheaply made
At least I don't feel so bad by not ordering another one.
You'll appreciate this - I figured out how to chuck the pulley in the lathe, spent a good 10-15 minutes indicating it in to less than a thou, drilled/reamed out the hole perfectly straight to 10mm, made one ever so slightly tapered press fit aluminum plug - about .001" taper for 2 inches - and the first plug was undersized (even though it was actually a little over 10mm). So I made a second, slightly larger plug. (BTW, I spent forever tweaking the tailstock for the itty bitty taper). That one seems to be perfect. It went in the freezer, the pulley went in the air fryer (don't judge me), and got them out, put some loctite 638 on it... and the bastard plug got stuck 1/8" from going all the way in. So then I was hurrying to clear the path to the hydraulic press (there's an antique desk from my dad's house from when he passed away a bit over a year ago in front of the press), and I pressed the ever loving snot out of that thing. You can see how the plug mushroomed under the force of the hydraulic press:
Then I chucked it back in the lathe, indicated it perfectly a second time (also took forever), drilled it out, and ran the 8mm reamer through it and... chips loaded up in one flute of the reamer and I ended up with a tapered hole that was 8.46mm on one end and 8mm on the other. Dammit. I put it on the motor anyway, and it's about the same as it was before all this.
I'm going to have to back out to the garage to do it all over again... argh. I'm gonna chalk this up to a lesson on how to use reamers properly...
You'll appreciate this - I figured out how to chuck the pulley in the lathe, spent a good 10-15 minutes indicating it in to less than a thou, drilled/reamed out the hole perfectly straight to 10mm, made one ever so slightly tapered press fit aluminum plug - about .001" taper for 2 inches - and the first plug was undersized (even though it was actually a little over 10mm). So I made a second, slightly larger plug. (BTW, I spent forever tweaking the tailstock for the itty bitty taper). That one seems to be perfect. It went in the freezer, the pulley went in the air fryer (don't judge me), and got them out, put some loctite 638 on it... and the bastard plug got stuck 1/8" from going all the way in. So then I was hurrying to clear the path to the hydraulic press (there's an antique desk from my dad's house from when he passed away a bit over a year ago in front of the press), and I pressed the ever loving snot out of that thing. You can see how the plug mushroomed under the force of the hydraulic press:
Then I chucked it back in the lathe, indicated it perfectly a second time (also took forever), drilled it out, and ran the 8mm reamer through it and... chips loaded up in one flute of the reamer and I ended up with a tapered hole that was 8.46mm on one end and 8mm on the other. Dammit. I put it on the motor anyway, and it's about the same as it was before all this.
I'm going to have to back out to the garage to do it all over again... argh. I'm gonna chalk this up to a lesson on how to use reamers properly...
only thing I am not so comfortable with are the 6 (not 4?!?) wimpy m4 screws holding the motor ... quite some weight hanging there when the motor is horizontal. Some bumps later ... gulp.
For the long run some additional clamp around the motor body might be indicated ... (yeah I know small steps, feasibility first!)
For the long run some additional clamp around the motor body might be indicated ... (yeah I know small steps, feasibility first!)
MkngStffAwesome
Active member
yeah i know what yo mean the TP like min only has 4 m3 screws ultimately holding it together lol
Don't underestimate the strength of bolts. Consider this: you can pull an iron-headed/iron intake big block Ford with the massive C6 transmission bolted to it safely using only the 4 carb bolts. A single 12.9 M4 screw has a proof load of over 1,900 lbs - or 864 kg. 6 of them are more than adequate. The aluminum they're threaded into is the weakest link, but even that's way more than enough.
Kinda surprising to think about, frankly.
Kinda surprising to think about, frankly.
oh ... in the RC world those overbuilt/expensive brackets are very common.
MGM is e.g. having this one:
LMT motor mount
The easiest way to mount your motor to your RC car. This motor mounts first the most of the 1/5 RC motors.
www.mgm-controllers.com
made me a bit nervous, LOL
and as you said it is the aluminum casing of the motor where I am concerned about regardless of the hardness of the bolts you picked with the limited thread engagement to the base plate (the motor base plate is bolted with some "unknown" bolts to the main cylinder as well) ... and the leverage of the motor weight when mounted horizontally.
Probably I have too much time thinking (so overthinking) ... need to just put my shit together soon.
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@AlexLTDLX ... quick question:
Are you getting the sensored version of the LMT30100?
I have the feeling the VESC will work better with a 2 pole motor like the LMT ... and the sensors (if sensored) most likely will help a lot with syncing the motor in low(er) throttle positions.
Are you getting the sensored version of the LMT30100?
I have the feeling the VESC will work better with a 2 pole motor like the LMT ... and the sensors (if sensored) most likely will help a lot with syncing the motor in low(er) throttle positions.