VESC - Land of 1,000,000 choices

That is true. Dollar for dollar, it's pretty tough to beat, which is why I want to get it to work with the cheaper setup. It's fine if you don't mind playing around for a while. I also think it'll get better/more evolved on the software side, particularly with regards to the motor id stuff and hopefully to automate certain settings. For example, when doing initial setup, it could ask you, "what kind of eRPM are you trying to reach?" and then automatically raise the frequency if needed.
 
Well guys, I dunno. I tried it again today and I couldn't get it to repeat. No matter what I tried today, I just can't get above 110,000 eRPM without current spikes anymore. I'll see what they say on the VESC forum and from Frank directly. I'll keep you updated. I think I've wasted too much time with this, and I'm going to start work on the Sledgehammer, while I wait.
 
@AlexLTDLX
"The only difference is I charged the batteries - took them from 59 volts to 62 volts"

So maybe there are voltage spikes that you can't see within the app causing problems..
If you just move the terminal on the batteries one cell over you could nock off 3 ish volts.. it would be interesting to see if the problem goes away again.

Then if dropping the voltage helps. Then that raises the question of what happens if you drop another sell ..maybe that's all part of the problem (voltage).. I know the mosfets say 75v .. but you'd never expect them to work with a 75v input voltage
 
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I've already started work last night on the Sledgehammer. I've invested too much time into trying to make this work. I think in order to make the VESC play nice at high speeds, you'd need a motor with fewer poles - like a 4 or 2 pole motor. Maybe they'll come up with a firmware update or something in the (hopefully near) future that will make this work better, or maybe I'll switch to a sensored motor with fewer poles, assuming I can find one for a reasonable price (LMT stuff is great, but the shipping time and cost as well as overall cost is a bit painful).

Honestly, just watching my youtube earnings dwindle while posting a bunch of "trying to make it work" videos is a motivating factor too.
 
Update - also posted in the P2 thread - I decided to try a different motor. Going with a Castle Creations sensored 4 pole unit. Let's see if that helps.
 
Update - also posted in the P2 thread - I decided to try a different motor. Going with a Castle Creations sensored 4 pole unit. Let's see if that helps.
Interesting Alex. Can't wait to see the data.

Sorry guys I have been missing in action. Been working on some clients projects. Should be full tilt back my CTS build in about a month or so. Also I have purchased all new tools. Move to all Milwaukee cordless stuff. Buying a CNC also. And looking for nice mini lathe to machine small parts also, any recommendations?

Just don't like waiting for parts when i could make them myself.
 
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I understand that. In my opinion a lathe is more useful than a mill. With the right tool post attachment, you can do a number of milling operations on a lathe. I have a Harbor Freight lathe - the one that was a step up from their mini lathe, but they don't appear to sell it anymore (8x12, iirc). The cast/machined parts on it are ok; the motor plate arrived really bent and it was missing a shoulder bolt for one of the handwheels - that's the first part I made on it. It doesn't have variable speed (except by adjusting belts). That's one thing I'd love on it. It would also be nice if it had a carriage lock and a quick lock for the tailstock. Those things are modifiable, though. Be prepared to spend another $600-$1,000 on tooling; though obviously you won't need to all at once. Once it's all dialed in, it's actually pretty good - you can easily hit accuracies of .0005" on it. From an "unfixable - that's just the way it is" perspective, the leadscrew for the carriage is what it is. Since it serves the purposes of cutting threads as well as carriage movement, it doesn't get particularly fine; but that's not that much of an issue. If you want a finer finish than you can achieve with the leadscrew, you can always move the carriage by hand, or simply polish the part with some emery cloth - which is common practice anyway. But I've found that for almost everything, it's not necessary. Having reverse is nice too (not all lathes have reverse).

Ideally, you'd want a lathe large enough to turn brake rotors on. But I quickly discovered going much over an 8" swing starts to get really expensive (and heavy) really fast. If I could've found a good condition vintage american made lathe for a good price (like a South Bend or similar), I would've bought it. Perhaps not surprisingly, machine tools around DC are not plentiful. So it is what it is. Overall, for what I've been able to do with it over the years, it's more than paid for itself, and the ability to quickly make small parts (fittings, washers, custom bolts, standoffs, motor mounts, event making a custom tool or two) is irreplaceable. I use both my mill and my lathe with about the same frequency, but about half the mill work could be done on a decent drill press and/or the lathe.

Here she is, in situ:
Lathe.jpg

In fact, in the last couple of days, I've been using it quite a bit late at night. I made standoffs for the LMT motor support out of an old weedwhacker shaft tube with some slip fit and loctited plugs at the end for centering and structure - that keeps the weight way down and drilling a hole that long through solid stock is possible, but a pain in the butt:
Standoffs.jpg

I also had to make thread adapters for the stand offs; the threads in the blower case are a really odd size (esp. considering everything else on the blower is SAE; these holes were metric). I can guarantee that nobody on earth stocks M12 x 1.75 to 5/16" UNC thread adapters:

ThreadAdapters.jpg
 
FWIW, chinese tooling, esp. carbide stuff, is hit and miss. And none of it is as good as the real stuff. I found a set of Sandvik inserts that just happen to fit about half my tool holders as new old stock on ebay for a fraction of the new cost - they put chinese carbide inserts to shame. Plus they last a lot longer. On the flip side, I did just pick up a boring bar set for a bit over $30 (I needed a 7mm boring bar to machine the impact socket for the hex drive 10mm bore - impact sockets are made from some really tough steel that immediately kills HSS tooling), and those inserts cut through the socket like butter. But none of the other chinese carbide inserts are great. They're ok, but not great.
 
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