Diy Brushless Spindle

[blackburn mark]

did you put a groove in the ER collet shaft for the circlip or not?

no.... my thoughts where that the tight fit (bearings n housing) would hold it all in place, iv had no problems so far using the double row a/c... i did have an issue with one my C8 spindle bearings (cheap skate bearings/bad fit on the shaft) resonating the inner race around the shaft at certain speeds so i used a bit of epoxy on that and its been ok so far.... now i think about it i guess the bellville washers become redundant once the glue has set and when the bearings wear i might get some slop ... it may need some further thought

What RPM do you use the flycutter at?

hi adam... iv not measured rpm's for a while however im pretty sure i skim acetal at 1500rpm and aluminium at less (maybe 1000rpm) thats with a 30mm radius fly cutter

with aluminium i have to be pretty careful (light cuts) or i get resonance patterns but im pretty certain thats my gantry sides and not my spindle

i should really do a test to see how low i can take the rpm and still cut with the fly cutter but iv never seen the need as iv allways got by at those speeds

[njhussey]

Dissassembled the motor, worryingly there was no locktite on the grub screw holding the body onto the shaft....needless to say there will be when it goes on the collet :naughty:

Am ashamed to say that for the first housing I'm cheating and getting someone else to machine the housing as they have offered to do it for nothing (our local machinist we use at work) in between jobs they are currently doing...which is very nice of them. I'll use the other bits I've started to do a smaller high speed spindle for engraving

At some stage I'll re-wind it as the winding is poor and also the potting/epoxying of the magnets wasn't too clever either as some was proud and was rubbing on the armature. Still you get what you pay for so I shouldn't be too surprised I guess...

[Villacherman]

Neil,

Does the rewinding take much effort? That's to change the v/RPM?

I'm waiting to see how things go with yours to start mine, looking forward to it! :)

Adam

[njhussey]

Adam, I don't know how much effort it will take. I'll do it to tidy up the winding (see photos) as it's not very neat but will not bother at first as I want to get the spindle up and running first!

[Jonathan]

You'll find lots of info on rewinding this type of motor on the rcgroups forum. If it works fine I wouldn't worry ... but if you want to change the number of turns to get optimal kv then it's got to be the way to go.

I wouldn't say you've got what you paid for when you paid more than the going rate for that motor:

http://www.hobbyking.com/hobbyking/s...idProduct=4913

I've not had any from hobbyking with poor magnet potting...but I've only bought about 10 and not the one you got.

[njhussey]

Jonathan - Yeah you save yourself about £5 but have to wait 2 - 3 weeks, I bought mine on Thursday night and it was delivered to my works (no Sat deliveries) Monday am, you won't get that with Hobbyking One of these days I'll pluck up the courage and order something from there :tup:

Turnigy motors are good motors, I've had a few in my planks and only had a couple of issues (loose magnets and noisy bearings.)

[njhussey]

Single AC bearings finally arrived today, this is the second lot as the first lot never made it...

Run out of time to do the spindle this side of Xmas as off visiting relatives after the end of this week till the New Year!

[Villacherman]

Neil,

Sorry, I'm on lunch at work so I didn't have time to look through the thread... you are putting one bearing in front and one in back (of the housing which is out front of the motor), correct? What type of fit are looking for on 1) the shaft and 2) in the housing. Press fit I'm assuming, but roughly how much force?

I'm assuming this will cause some pre-load on the bearings... and with more interference on the fit, the more preload on the bearing.

Have a good holiday... anything I should not miss up in Newcastle? I'll be there for a couple weeks...

Adam

[njhussey]

Hi Adam, not been on here for a while as work was mad (trying to get a quote out and clear my desk) last week, 57 hour week...

I've tried the bearings on the ER16 collet shaft and they are disappointingly a loose sliding fit...will be a light press fit (heat housing first and slide the back bearing in) in the housing with Bellville washers pretensioning the inner races. Will have to locktite one bearing to the shaft and I guess leave the other a loose fit to keep the pretension? If the bearing starts skidding on the shaft (like Mark's did) then I'll have to locktite that too I guess.

I don't know Newcastle or the surrounding area, never been to that part of the country yet, so can't help you on what not to miss I'm afraid!!

Hope everyone has a Merry Christmas & a Happy New Year!

[Swarfing]

Hey guys how is this thread progressing?