Quark regenesis! - RC-Monster Forums

zeropointbug · **Quark regenesis! -** 06.23.2009, 12:01 AM

Hey guys.

Now I know lot's of you won't care, or some of you don't even know what a Quark is, or just forgot... but I thought I would post this anyways.

My Quark has been pretty good up until now, started glitching and cogging, and shutting down with my new 35C lipos when on the brakes for the first 5 minutes of running. I have a race weekend this weekend, so I thought I would do an overhaul of the Revo to make it 'race ready'. Opened up the Quark, and damn, the two caps inside the thing, the leads were simply melted off, so they were useless... only the outer two caps soldered to the batt leads were still good. Not good. Anyways, I thought I would do a few other things to make it race worthy. Enjoy.

zeropointbug · 06.23.2009, 12:03 AM

some more pics

zeropointbug · 12:29 AM

and an arse end pic

Wires are all 10awg... kinda ran into trouble with the input leads as it was pushing against the case, so I had to grind away a section so it would sit properly. Cap bank is made up of 6 35v/330uF low esr caps, the same cap bank from the "FrankenQuark". I also used thermal adhesive on the heat spreader as you can see.

BrianG · 06.23.2009, 12:14 AM

lol, some of us "old timers" love our Quarks! :P

zeropointbug · 06.23.2009, 12:26 AM

Yup, I like the Quark... I will buy a MMM when it dies, although it may never die now.

Also Brian, I meant to put this in 'Brushless' board, you can move it if you want, no big deal though.

MTBikerTim · 06.23.2009, 12:29 AM

Do you just plug the battery in then unplug it and go race?

zeropointbug · 06.23.2009, 12:31 AM

haha, not quite, I only get 2 minutes of runtime off the cap bank, so not enough to finish a race...

06.23.2009, 12:45 AM

Thats sweet. It really gets 2 min of runtime from the caps?

MetalMan · 06.23.2009, 12:50 AM

If those caps don't do the trick, then sadly nothing will

zeropointbug · 06.23.2009, 01:27 AM

hehe, well let's hope, I don't want to be racing the nitro guys (and they are all nitro heads) and have the Quark do it's stupid shutdown thing...

It happens for the first 5 minutes of the pack roughly... when going at a decent speed, use even a bit of brakes, teh Quark just shuts down control, no brakes, no throttle, no nothing, at least for about 10 seconds of fiddling with the throttle/brakes trigger. I'll have to test it out, if it still does it, I will have to use partially charged packs, 4.0v/cell charge?

I am currently running around finding parts like angle the make a mounting bracket for the RC-monster heatsink it will be thermal adhesived to (is that a word?) I'll have more pics in a bit.

cheers

BrianG · 06.23.2009, 01:31 AM

What you describe sounds EXACTLY like what was happening to me with my Quark for a little while. Turned out the UBEC I was using (a cheapie $5 Chinese one) was the culprit; it was cutting out causing the ESC to "reboot" because of receiver signal loss. Replaced with a DimensionEngineering BEC and has been fine ever since. And this was all with 4s lipo.

zeropointbug · 06.23.2009, 02:31 AM

I'm using a PRO-BEC that S&T sent me the last time they replaced my Quark. Has worked perfect for 2 years now... I'll see what happens, I have an unknown BEC, and a Ultimate BEC I could try as well.

Okay, as I was typing this, I checked the BEC, one of the wires is brocken off... but it's the orange lead, which is not a power lead, and doesn't matter does it Brian?

BrianG · 06.23.2009, 09:56 AM

No, the orange lead won't matter as it is the signal wire, which is not used.

florianz · 06.23.2009, 02:14 PM

hi,

good idea to add some more caps than usual. I have modded some chinese-plane-esc which I have used for my buggy conversion (the last two died because of water, but performed well...). I have at least doubled the capacaty of the caps, I changed the original ones by more and bigger caps. Size DOES matter

I just can say that the throttle is very smooth, and the esc doesn't get hot. Not even once it cogged. sure, brake's crap.

I have read a couple of times that more caps can help to keep the esc cool and prevent cogging; Schulze recommend for their esc to add caps in some cases.

Do you feel a difference now?

florian

zeropointbug · 06.23.2009, 02:39 PM

Florianz, yes, caps make a difference, but it's not the size that counts, it's the low esr (equivalent series resistance) values that help the esc. That's why I have the cap bank right inside the case, soldered directly onto the board with a heavy buss bar. I would love to have some solid polymer caps to use on it, very low esr and small, and very durable.

My last Quark I modified, HERE, worked wonderfully, rarely cogged even geared to the moon, and ran super cold (most likely due to the heatsink it sat on, which actually increased to value of copper world wide when I put it in there, lol). It was too heavy, and was eventually killed because of physical damage from a hard crash.