Cutting a motor commutator & motor tweaks

[4xFord]

Originally Posted by The Violator

It's clear brushless is superior in almost every way. The pro4 motors proved that lots of power can be had in a small package. The only issue I see is drag brake. Without a substantial improvement in brushless drag brake I think we are pissing up a flag pole.

Outrunner drag break can't be touched.

EDIT: Actually, homes hold on the BRXL is about the same with brushed 540's.

[JohnRobHolmes]

Originally Posted by binaryterror

I want to get back into cutting, but sold my good lathe years back and this Trinity one I kept (I have no idea why) is impossible to cut with....looks like I'm off to ebay for some deals.

You checked the condition of your bit? Sounds like it is chipped or dulled.

Originally Posted by 4xFord

I have a question.

So, what brush setup is ideal for higher voltage? I would assume a stand up, because less chance of arking the comm, is this correct?

Standup to reduce the commutation duration to reduce arcing. You also get lower amp density along the leading edge. Round brushes do even better, it is a nice sinusoidal ramp up of current. Heavy springs keep arcing to a minimum too.

Originally Posted by The Violator

It's clear brushless is superior in almost every way. The pro4 motors proved that lots of power can be had in a small package. The only issue I see is drag brake. Without a substantial improvement in brushless drag brake I think we are pissing up a flag pole.

Outrunners kill it on drag! Just wait until I get the Holmes Hold on a BL ESC...

Originally Posted by 4xFord

Oh yes, 3 new ones for $25 shipped!

Killer deal!! I wonder how many of us are scouring ebay for old parts? I picked up a nice old motor lot for $50, and it came with a Hudy lathe!

[TEDROCKZ]

Originally Posted by JohnRobHolmes

I wonder how many of us are scouring ebay for old parts? I picked up a nice old motor lot for $50, and it came with a Hudy lathe!

X2 I was thinking last night about how many of us on here are probably bidding against each other

[Cordwood]

Originally Posted by JohnRobHolmes

Killer deal!! I wonder how many of us are scouring ebay for old parts? I picked up a nice old motor lot for $50, and it came with a Hudy lathe!

Damn, I have a bunch of saved ebay searches set up that prompts me when new stuff pops up and I never even saw that one.

Originally Posted by TEDROCKZ

X2 I was thinking last night about how many of us on here are probably bidding against each other

No kidding. I got outbid last minute the other night on something and I thought to myself, "I wonder which one of those f'ers in the comm thread outbid me!!"

[schiesz]

Originally Posted by JohnRobHolmes

I picked up a nice old motor lot for $50, and it came with a Hudy lathe!

That's the killer deal! I've been trying to find a decent Hudy to try my hand at this, and all the ones I find are starting around twice that price.

[JohnRobHolmes]

I won't tell yall how much I paid for the motor lot plus Motor master then, lol! I did proceed to kill the motor master within about 10 motors though. Had a lead slip off a motor and it shorted the FET inside. Back then they didn't have current limiting built into those sorts of things.


I'll post up when I get around to tearing the thing apart and replacing the FET. I have a bunch of the same TO-220 legged fets here from building ebike controllers to my specs.

[Cordwood]

Originally Posted by JohnRobHolmes

I won't tell yall how much I paid for the motor lot plus Motor master then, lol! I did proceed to kill the motor master within about 10 motors though. Had a lead slip off a motor and it shorted the FET inside. Back then they didn't have current limiting built into those sorts of things.


I'll post up when I get around to tearing the thing apart and replacing the FET. I have a bunch of the same TO-220 legged fets here from building ebike controllers to my specs.

Awe shucks, you could of offered to fix mine when that happened to me doing your timing advance by amp draw method. Cost me 63 bucks through hobbico to get it fixed

[EddieO]

Hudy Lathes can be tougher to find good deals on, because they can easily be converted to a slot car lathe....slot car guys will be using brushed motors till the end of time.......so the lathes are not as easy to find cheap. The orion, reedy, trinity, etc are ALL capable lathes. Don't get caught up on having to use a Hudy......I only use mine to cut mini motors. If anything you should be caught up getting a fantom....there is a reason I have 6+ of them.

I've been saying all along there is TONS of good stuff out there. RC racers don't throw stuff away, just gets put in the closet.......they will give it away for nothing to another hobbyist before throwing it away. It's much cheaper to buy a set of arms and get them rebuilt than a whole set of motors.........4xfords deal is a great example......basically $15 for a pair of motors, $60 for some armatures.......$75 bucks and done!

Round brushes with heavy springs would probably have the ability to handle more voltage the best. Your big issues with voltage is brush bounce, along withDetonationof the comm. Round brushes counter act this the detonation, while stiff springs help the brush bounce....if I was to pick, I would say the v2 brushes do a better job of it than anything out there.

I might get bored to day after orders are done(yeah, EddieO works on saturday too).......post up a pic of tool, see if anyone can guess what it is......maybe a prize to the winner?

Later EddieO

[Hulksta]

As Eddie said the fantom is the one to chase, it's very sturdy you could droop it and still cut a perfect comm, others you would need to check its true still

[Cordwood]

Originally Posted by EddieO

I might get bored to day after orders are done(yeah, EddieO works on saturday too).......post up a pic of tool, see if anyone can guess what it is......maybe a prize to the winner?

Later EddieO

Waiting.....

[EddieO]

Any idea what is? What it was for? How much it cost?

There was only ever three of these made......



Some brood fluids to first person to get first two questions right

Later EddieO

[TEDROCKZ]

Stack and comm jig!!!!!! used to align comms

[EddieO]

Right on A....not for B....well I guess sorta could be used in that.

Later EddieO

[Cordwood]

Change the alignment, to cheat in stock class

[EddieO]

So cynical! No, no cheating by brood...we didn't have to cheat to win....that was the OTHER teams.

Later EddieO

Originally Posted by Cordwood

Change the alignment, to cheat in stock class

[Cordwood]

I'm stumped if it didn't check or change the alignment.

It's probably some of the internal parts to your jigatron-2000 penis pump...

[EddieO]

Well there ya go, you answered it without even realizing it...

It was used to check the comm timing. We never used it to adjust it really though, as it was too delicate and expensive for something like that. Stock motors often had comm timing all over the map, so when you buy 3 handouts.........times 10 racers, it was much easier to figure out which arms would be better than the other using simple tests (those sometimes arms defied logic).

Only 3 were ever made, one for his son, a national champ......he made one for me and one for Scott Ernst, who runs a lot of races as a tech tool.....they were EDM cut.....cost, $400.

Later EddieO

[Cordwood]

Looks like a handy little tool.

[EddieO]

It was very handy back in the day.....

I use it now during the matching process....getting stuff as identical as possible prior to building them makes the motors pretty much in sync once they are built...

Later EddieO

[JohnRobHolmes]

Originally Posted by Cordwood

Awe shucks, you could of offered to fix mine when that happened to me doing your timing advance by amp draw method. Cost me 63 bucks through hobbico to get it fixed

I wasn't aware I missed a chance for an offer Using the amp draw method does have the ability to kill parts if the timing gets way off. What happened, did the endbell slip?

Originally Posted by EddieO

Any idea what is? What it was for? How much it cost?

There was only ever three of these made......


Later EddieO

Cool little tool! I bet it really helps spot the differences between arms. Cut for 7.5mm arms?