Anyone with CNC machines knowledge?
I might be able to buy this machine from China:
Within my country it is almost imposible to buy a cnc machine for iron, hardened steel and hard aluminum for your home. This is just an opportunity, but I do not know the quality of the machine or the manufacturer. This works with Mach 3 cnc program. I will really appreciate anyones thoughts. I was thinking of servo motors, and 4th Axis…
For a Chinese machine, that looks pretty good. Linear rails and ballscrews on all axes, decent travel, and way covers to keep chips and dirt out of the motion hardware. Of course the devil is in the details - Whether it’s all straight, flat and square to itself in all axes is the big question, as well as how feasible it would be to tram it in or adjust it if it isn’t.
Thanks for the reply, I am afraid of that, ask around here, some guys said Mach 3 software will compensate that issue if it does not vibrate…Hope so…Thanks again
I’ve always heard the adage of “Treat a chinese machine as an 80% kit” - 80% of the work is already done, but it’s on you to go through it and find all the little things that are wrong/missing and fix/adjust them.
You can make a cheap Chinese lathe (for example) into a pretty good lathe, but it won’t be out of the box, that’s why they’re cheap.
See if you can play with the maximum and minimum switching frequency in BLDC
As an experiment, if I wanted that, and I do love motor noise, than I would first try lowering the maximum switching frequency.
Yes…people in my country buy drill and milling cheap Chinese machines, put some motors and software, then use it …but they are not really precise…Also really expensive…I think I might try…it is that or never know here…
Well, I think you’ll have at least a bit of an advantage due to the ballscrews and linear rails - as long as the frame isn’t twisted or warped, that should get you started pretty well in terms of precision.
Definitely check the machine with an indicator and/or a square, straight edge, etc before you accept it. If it’s crap, send it back and get a refund.
Yes, I’ll do that, thank you, appreciate your help
I have such a specific problem Im not entirely sure anyone can help and its not even a sizeable issue until it becomes one but my e-switch built into my maytech 4.20 VESC seems always closed regardless of whether the switch is depressed or not, thinking the ground for the switch is shorting with main battery negative if anyone thinks that would emulate the closed loop.
The primary failure mode of those FETs is to fail closed – which manifests itself as an “always-on” condition. This might not be your problem, but it’s probable.
You could just use a loop key 
Oh I do use a loopkey, was just wondering if it was something I fucked up or just something that happens.
Thank you!
Pretty sure the answer is no. From what I can find searching on these they run on 12V power and just trigger a relay to allow the current for the starter to flow and looking at the wires and connector just guessing can’t put that many amps through a thin wire like that without having it melt on you.
Edit I guess if the question is can you use this as a “button” in place of an LED switch or the like then the answer might be yes but definitely no to directly having the power flow through that switch.
@wafflejock Through my searches, I read about high current ignition switches (for systems without relays/solenoids) but couldn’t find any. Wires can always be changed but I’m pretty sure the circuit inside the switch would melt
Yeah I picked up one for cutting off power on boats that I think was rated high enough but it was/is massive so I never tried putting it on the board, probably should have checked the dimensions before I ordered it was this one:
thing is huge though and yah never installed or tested because is just too crazy looking and massive (this coming from a person with brick lipos on the board and a hole drilled in the nose for locking up)
Edit have heard of others using breakers I think since they can handle high current depending on the type of breaker and aren’t quite as big as the one I linked but still very bulky, personally just unplug my lipos or used a loop key built into a case in the past.
been thinking of a mtb build with 9’’ tires. I want a second pair of wheels for road use and much better range. Is there a big difference between Gummies 125mm and Haggy 147mm wheels? I prefer pneumatics and haggy having the smallest diameter should be great for range but is the range really better with gummies? not interested in tb 110 because i want an AT gear drive
I’m sifting through spare parts and realized I have an old Wowgo 10s2p Samsung 22p pack and a set of hubs. 10 amps per motor does not seem like enough but I guess it worked before when it was a pre-built.
I wonder what kind of performance I’ll get out of it. Doesn’t 20 total amps seem too low for anything, or am I just privileged with 80+ on my custom boards?
The answer as always is it depends, only way to know what you’re actually drawing on a given setup is to slap some bluetooth telemetry on there and see for yourself… that or just limit your amps on one of your higher powered setups and see how much of a difference it makes in acceleration.
Generally low battery current will not affect your starting and low speed torque and acceleration much (0-5 MPH let’s say) but your torque/acceleration will taper off more steeply as your speed increases, when compared to a higher battery current.
As long as there’s enough power to overcome drag you’ll still reach the same top speed, but it’ll take longer.
