Diy Brushless Spindle

[njhussey]

i could have sworn i sent you some

B***er...can't remember getting any...I did move house back in March tho so maybe they're there?

[blackburn mark]

i think they where sent in may... PM sent

[njhussey]

PM replied to Mark.....

I've got 150 off P188207 Belleville Washers coming early next week so think I should have enough for this and any other spindle I might be wanting to do :D

[m.marino]

Question to you guys is how well do the DC motors handle heat when running at different RPM's? Also would setting up a PID type closed loop controller work with a DC motor? Looking at options with one of the other members and a DC brush-less motor is looking like the best option for providing the need power and from the looks of it the needed RPM's as well. Has anyone though of side mounting the motor and connecting it via belts to the spindle (possibly using a key way to help lock the pulleys to their spindles). This would some variance in torque and from what I can see would really make the spindle have a rather wide range of uses.

Just asking as kicking around ideas and designs and these are points that have run across. Anyone happen to know a source for variable speed AC motors in the 1.5kw range that don't cost the moon or come from questionable quality control?

Michael

[Jonathan]

I'm not sure if you're referring to the motors discussed in this thread, which are brushless AC motors, or normal DC motors? Either way a PID control algorithm can be used to improve the performance. A DC-servo motor is just the motor with encoder and PID control for position and speed.

[blackburn mark]

Question to you guys is how well do the DC motors handle heat when running at different RPM's?

I’v had no issues with motor heat... i could confidently push my spindles much harder if I needed to.
Where i do have concerns is the ESP (speed controller) they do get hot... iv not blown one yet but i bought a spare because i thought i might with the amount of heat they push out (no problems though so far) at £20 (ish) its silly not to have a spare.

with a 12v 350w power supply the majority of my spindles are vastly under the “claimed” potential and iv not once thought I needed more power/torque… im sure our honorable speed freak friend Jonathan would want more speed n torque (you would need the extra speed if you wish to cut wood…I’m cutting plastic 90% of the time, I don’t cut any wood at all)

if your cutting wood and alli/plastics its worth weighing up if making two spindles is easier than dealing with pulleys on one ?

[njhussey]

Most model ESCs are mounted where there us some airflow (the ones I have in my planes all have air ducts directing air onto them and the one on my Trex 500 heli is on the side so in the downdraught) so I'll be putting a 24V fan by mine for cooling.



Belleville washers arrived today but just back in from a weekend away so will be tomorrow before I complete the spindle now :)

[Jonathan]

Most model ESCs are mounted where there us some airflow (the ones I have in my planes all have air ducts directing air onto them and the one on my Trex 500 heli is on the side so in the downdraught) so I'll be putting a 24V fan by mine for cooling.

A fan does make a big difference to the ESC (not ESP! ) temperature - I put fans on the ESC(s) in my model car for the same reason. A lot of model car ESCs include fans now since the airflow tends to be poor in that application.
Bit off topic, but is that a genuine T-rex or did you get a cheap copy? I got the latter, but can't say I've used it much yet as I always seem to have other things to do...

How much did all those springs cost?

[njhussey]

It's a genuine Trex 700 nitro, don't think HK do a copy....yet ;)

The main reason I've not got further with this project is I've probably spent 2.5k on helis in the last 18 months to the exclusion of everything else!

They cost £15 + the dreaded and P&P so I think approx £25 in total...still got about 130 left :)

[njhussey]

Bit off topic, but is that a genuine T-rex or did you get a cheap copy?

Just realised I'd said I had a Trex 500 in my text....yeah it's a genuine one...my Avatar is the 700...I did buy a HK450 but it's a bit like buying a router made from MDF with unsupported rails lol