Most ESCs have them right near where the power wires are, so anywhere near there is fine. You could even solder them to the actual power wires too; just strip back a tiny bit of insulation as close to the board as possible, wrap the cap's legs around each wire, and solder in place. You probably should find a way to insulate that area a little to prevent shorts. If you use a wired cap (like Novak uses), keep it as short as possible; makes no sense to use a low ESR cap if you add wire resistance.

The caps are marked with a stripe or even a - symbol on the negative lead.

the stripe is negative or positive?

The wire stripping thing is what I was thinking. Just wasnt sure if it mattered how close to the board it was.

Geez, I'm going to have to go back and re-read this whole thread. I've almost forgotten exactly why it is that we're doing all of this. Will this make things easier on the batteries?

OK, someone is going to have to post showing the most creative way of mounting these things.

ah Geez, you forgot already?! :005: You were even 'Franked' today on the phone! :005:

jhautz, yes, the white strip will be the negative lead.

A good idea of mine to mount up to 6 caps, is to tap the input leads with short run of wire, say 6cm, long enough to mount 6 caps down the length. I would strip slots in the wire insulation for each caps leads to penetrate the wire, and solder each cap into each slot in the wire. Or you could make the half the length and mount two caps per slot (one on each side). I would then shrink wrap those caps, or use the packing tape (the strong stuff with fibers in it) to secure them. You will want to mount these in a way that they WILL NOT bounce around or get physical abuse, indeed they can't handle that $HIT.

Let me know if you don't understand what I meant.

ZPB

You're talking about having two strands of wire 6cm long with caps hanging off of them and then soldering these wires to the input leads, right? If you do that, how would you keep them from bumping around. Also, if you shrink wrap them, how is the heat going to get out?

Man, if I had a strip of anodized aluminum, I'd make a cap bank and epoxy that thing to the top of the quark.

What about this...

Make a cap bank using two strips of copper. Solder that all up. Then take the bank and use some sort of electrical insulator. Maybe just a piece of themal pad and stick it to a piece of thin aluminum. I mean really thin. Thin enough to bend with your hands. What I ultimately envision is an aluminum box with the caps inside. Before you make the last fold of the box, you could wrap the ends of the box with tape and fill the whole thing with thermal epoxy, leaving the two copper tabs sticking out for soldering a piece of wire to so that you can tap into the power leads. For the epoxy, you could just use some devcon two part. When you mix it, just add a generous portion of aluminum oxide power for home made thermal epoxy. Voila, encapsulated cap bank that will shed heat.

You should try this homemade thermal compound. It's a lot cheaper than AA, but it doesn't work quite as well. It does work though. You can get the aluminum oxide powder from hobby stores that cater to rock collectors. Lapidary polish I believe it is. It's just aluminum oxide and does not conduct current nor has any capacitance. You'd be surprised at how well this stuff moves heat.

Here are some caps I just installed on a couple of ESC's. I just put 2 on each ESC. The CRT with the with Quark and the MM is going to be for an 8ight buggy. I did have a chance to run the CRT. It was running really great, but I had changed the gearing all around. I put HPI Pro diffs in front and rear and changed the center diff to 46/12. The changes were all good.

Did the caps make a difference? Was there any temperature benfits?

The Quark was running a lot cooler but I don't know if it was from the grearing changes or both. It was at least 90*F that day and the Quark was at 112* after 20 min and usually it is at 130-148*F. You can't really see it in the pics but I have the heat sink and 2 of the 40mm fans underneath the ESC. I wish I had more of a definite answer.

Btw those caps are the 270uf ones.

AAngel: That does sound like another good idea. How thin of copper were you thinking? I can't even get copper buss bar where I live, as it's a smaller town.

About the heat, with 4 extra caps on it, the heat output from each one will be much lower than the two in the Quark. Even with shrink wrap on it, it will dissipate more than enough heat. The wire would only be two pieces, + and -, all of your caps solder to this, down the length.

Since you mentioned this, I would like to see an RC car controller with a 'spilled' housing. It's like a moderately thermalling conducive plastic that is pored into an esc housing with the board, and a heatsink is sealed onto the FET's and protrude out of it, also, with 5.5mm plugs (female) sticking out of the housing. No dirt, shocks, or water can enter the thing.

That looks pretty good with the caps on the Quark there, the ones on the MM, the wires look a little small, IMO. How is your Quark mounted to your heatsink exactly?

Where did you get these caps? What brand are they? low-esr?

I looks like a person would have to solder 24 caps on a controller to get an equivalent ESR as these ultra-caps I purchased. Also, the rating on the ultra caps is at 1khz (0.0025Ohm), and the caps are rated at a standard 100khz (0.06Ohm).

BrianG, or anyone: Do you know how this will compare? At the different frequencies?

hi like i said #7 before.
just use 470uF/35V u-Low esr cap x 4(P) to soldered power-line.

it's will pretty cool esc, i am try long time.


By the way, something my experience,
you maybe need re-soldered quark power-line wire and motor line wire,
better need use PB-free solder with silver 6% or more and 220c temperatue up good solder.
it make sure your quark has hi-temp do not melt your junction.
this my experience..
hope this help.

zpb, I want to use strips that are thick enough to be rigid. I want to mount (epoxy) the bank to the side of the case and bend the strips down to meet directly with the power leads to be soldered. I'll then put a coating of liquid electrical tape on the exposed connections. I'm going to try to find some copper strips. If I find myself in a pinch, I'll just go to the hardware store and buy a length of copper pipe and cut strips out of it. I don't know much about metallurgy, so I'll take a quick resistance reading with my Fluke before I go soldering stuff to the pipe strips.

As for the caps, personally, I have no idea what will be the best, but I know what I'll be using.

andy, thanks for the info. I'm glad to know that the addition of the caps does indeed help to keep the esc cooler. I've been using silver bearing roisin core solder for a long time now. I got it at Radio Shack and is supposed to be for electronics. I like it because it makes a strong mechanical bond. I've actually repaired copper and brass parts withit and it holds very well. Much better than epoxy.

Cooler running, yes, i DO recall someone saying that? Do you remember who that was? :005: :005:

Have you seen the Mtroniks brushless ESCs? Those have the FETs mounted to the aluminum body/frame of the ESC, which also acts as a heatsink. There are solder posts (instead of your idea of using plugs). It is sealed in a semi-translucent epoxy filler-type stuff.

All of the caps are spoken for.

http://www.mtroniks.net/images/LgImages/GENtruck.jpg
I looked at the truck combo package when I got the Hvmaxx, but for the price the spec wasnt all that amazing:-
£199.99 for esc & motor- thats $400, I could buy the quark 125b & a good XL motor for less. Though it does look impressive in the videos:-

http://www.mtroniks.net/downloads.asp

I only I had known about RC-monster back then......

Oh yah, I forgot about that controller. That thing is well built IMO. Only if the Quark were built that way, along with usb programmability, and 6s capable, then it would be the dream controller.

Starluck RC used to carry the Mtroniks Truck ESC for something like $165 (that's when I bought mine). For that price, it's not too bad.

They can still be had for that price on ebay.

Would this ESC be recommended, or is it somewhat outdated?

Nevermind... just realized that it is only rated to 4s. :019:

Its still the only brushless ESC that advertises itself as "waterproof". I had one for a time that I used as a winter snow bashing esc. Actually didn't use it much though. Turns out when there is snow on the ground...its dang cold outside:019: and that kinda takes the fun out of it.:005:

It was solid for 12 cells and a 9L that I used it with. I never thermalled it (of course it was 20 degreees F outside :p ) Even had lipo cut off for up to 4s. Not really that bad, just not enough voltage and current handling for my tastes.

There were quite a few of those that smoked on 1/8 scale stuff though. Mine smoked. I think I also heard of issues with Mtronics and ubec's. The pro version was pretty good in the rustler we had. No problems there.

These are the caps I bought: http://www.digikey.com/scripts/DkSea...983-ND&Site=US

My Quark is thermal epoxied onto the heat sink which is mounted on the bottom of the top plate. There is a space cut out of the top plate for the Quark. Here are some pics. I need to straighten up some wires. Fans kept blowing out on me. Now that I that fixed I should clean up my wires.

I don't think that those are low esr. The only low esr caps that I could find on digikey's site wouldn't suit this application, unless I just missed them.

Dang, I think your right. I didn't look close enough when I bought them. Spent some time looking for the right ones this morning and they seem to be hard to find. I have found some others, but if I get 10 the price is almost as much as the 200 piece ones on ebay. Those seem to be a good size as well. 10 x 20mm. Some of the others are huge.

My wife's cat barfed all over my Gen Pro I have in the Rustler and it still runs great. Doesn't smell good, but it runs.

Would you be suprised to learn that heating cat puke to 150F still smells no matter how well you try and wash it off?:020:

Ewww. Too much information! lol

Yeah, because I had looked and looked on Digikey for hours, and could not find any low-esr caps, a few, but they were surface mount type, no good here.

Even if they are not low-esr, they will still do 'something', but nothing like low-esr types, or at least what low-esr are capable of.

Finnster: Yes, too much information! :002: :eek:

Yes, cats do have a tendancy to be sick just where you dont want them to; even if you pick them up and put them in the kitchen to be puke up a hairball they will still run into the livingroom and make a mess on the carpet. Cant say the goldfish give me that trouble though....

Cant wait to see how peoples rigs perform post 'upgrade'. Im thinking that in order to get reliable results for comparison (without caps / with caps), that something like a steady run up and down for 10-15 minutes should be done. Measure temps, run time, capacity remaining in batts etc using an eagletree and ICE charger or whatever- plot some graphs with the data. Then solder on the caps, and repeat the test, driving up and down in the same manner. Plot the results again and compare them to the original set; if all goes according to plan then you should get some pleasing results. The key is obviously to minimise the variables as much as possible in order to conduct both tests in the same way, as far as is possible/ practical.

That really would not be reliable and/or useful, as there are too many variables (including driving).

You really have to do it by feel, and general eagletree results... the average voltage might be a little higher, but the main results will occur inside the controller, FET switching efficiency, and cooler running (apparently), and more reliable running.

I have my hopes mainly for cooler running, and more reliable, which matters most.

Yeah, the scientific approach would be to run a before and after test with consistent runs. That is going to be hard to do.

I say just run it like normal and see how it does. And even though it doesn't offer a tangible performance difference, you can at least be secure in your mind that the existing caps aren't being worked as hard.

Exactly.

That's really my motivation for adding the caps. Cooler running and less stress.

They didn't come in today. I was hoping that they would, as my Quark came in today and I threw it into my 8ight truck. I also bought a small sheet of copper from my LHS. When the caps get here, I'm going to get on making my add on cap bank; after I pack some up for shipping that is.

zero, I wonder if your Quark will be up to snuff after adding more caps, in spite of one of the internal caps having blown.

I sent mine off to S&T, they said they would just replace it, no questions. The electrolyte would have damaged the board, as well as when there are no caps, there would have been damage done to the board.

I have a really good plan for a custom Quark case, I just need the distance from bottom FET surface to top FET surface. It will be about 1cm wider than the stock case though.

It will not need adhesive either, just regular thermal compound, which is nice.

Is this the PIC?

http://nexusracing.net/images/articl...NovakCap_1.jpg

I just bought a 200 pack of these as well. I definitely don't need 200. I'd hate to see them go to waste so if anyone else wants any PM or email me.

http://cgi.ebay.com/200-Nichicon-35V...QQcmdZViewItem

lol, pretty soon the manufacturer making those caps is gonna start wondering what all the demand is about! :)

I wonder what would happen if you put all 200 on 1 ESC. The more the merrier right!

I was about to slit my wrists. I wanted something better and more efficient so I ordered a Compro ($200+). That was defective, so it's on its way to the Czech Rep. Since I couldn't wait, I ordered a Quark. I got it yesterday. I was so excited that I wired it up and took it for a run. My first impression was, "man this is smooth." I ran it for a few minutes, then shut it down to go fix dinner for the kid. After dinner I came back out to run it, and what do you know...cogging. I knew it couldn't be the controller, so I removed the connectors and hardwired everything. It ran great for about two minutes, then more cogging. I desoldered and resoldered everything, still cogging. I call Quark and they say that there was a batch of controllers that had bad caps in them. I have to send it in. What are the odds that I could spend almost $600 on controllers and have nothing to run my 5S packs with? That's just my luck. Now I have two controller in the mail.

So...anyway, the caps came in today. They were waiting for me when I got home. I used some 1/8" copper round stock and put it in a vice and flattened it. I cut two strips and soldered four caps to the strips and then made a channel out of copper sheet and then embedded the cap bank in epoxy that I mixed with aluminum oxide powder. I didn't do anything fancy with the bank. I just cut away some of the insulation at the front of the power leads and soldered the cap bank in using some 12 gauge wire. Not pretty, but effective.

Some pics...

http://i154.photobucket.com/albums/s...r/DSCF0257.jpg

http://i154.photobucket.com/albums/s...r/DSCF0259.jpg

http://i154.photobucket.com/albums/s...r/DSCF0258.jpg

I took it out to the track to try to break it, so I ran for about 40 minutes. It was geared 11/44, which I don't think is undergeared, since I usually run 12/46 with the 8XL in a truck and 14/46 in a buggy.

After running and only giving the truck a break long enough to change battery packs, get this...motor temp 218...esc temp 110. The battery was so cool that I didn't even temp it.

I'm not willing to swear that the caps made that much of a difference, but I had some really cool running tonight. At this point, I may have to sell both the Compro and the Quark when they get back. I'm assuming that I'm going to get new units back. The Mamba Max was running way to good. When I say there was zero cogging, I mean exactly that. No cogging at all.

As far as "the more the merrier goes," it's looking like four is merry enough for the MM.

BTW, I did try the cap bank on the Quark, it didn't help. There's something really wrong with that thing.

I have the caps divided up and will ship them tomorrow. You guys should have them by Monday or Tuesday.