HACHI-RYOKU

[HACHI-RYOKU]

I’ll be watching this one. Good luck dude.

[HACHI-RYOKU]

greed4speed wrote:

(Sorry we got off topic ph2t)

It’s not too far off topic. Most people adding this much power are going to experience these problems. It relates.

[HACHI-RYOKU]

I would recomend something with a fat armeture, like a Plasma-Atomic or a Anima-p or Anima modified motor. Those seem to hold up better from what I’ve read. You get more surface area to pass current anyhow so a fat armeture is generally better to begin with.

[HACHI-RYOKU]

Good stuff. Is it AWD?

[HACHI-RYOKU]

That’s good info Yank. Just curious, how long of a run do you get with those batts? Are you running it hard for a long time or are you taking breaks between runs?

[HACHI-RYOKU]

Allright. I’ll stand by until you do a test run and go from there.

[HACHI-RYOKU]

Hey PH2T, has the Nelly EVO been tested in an AWD Xmod EVO with a hot motor? My Nelly EVO is getting hot. First I tried it with a Plasma-Atomic, then I switched to an Anima modified motor. With the Plasma-Atomic it got hot within 30 seconds and the motor didn’t even break a sweat. I tried lowering the gear ratio and that gave it an extra 20 seconds or so before it got hot. With the Anima modified motor it takes a few minutes to get hot and the motor actually gets a little warm too.

I’ve also put in a cf shaft, bb’s and got rid of extra plastic to lighten the car. I’m using stock aaa nimh’s. It performs great, but I definately don’t want to blow the turbo. Should it be getting this hot?

[HACHI-RYOKU]

This was over a month ago now, but I figure you still might need it or it’s good info for other people. Here’s a few pictures of a ball diff. On the end opposing the gear you have a cylinder piece with a hole in it. There is a small grub screw that goes in that hole. You slip the cylinder piece on the axle and lock it in place with the grub screw.

[HACHI-RYOKU]

It’s a small black screw that should have come with your ball diff set. You need a really small allen wrench to screw it in. It would go on the side without the gear on it. I’ll try to get some pictures of what I’m talking about because I can’t really think of the names of everything or describe it very well. It sounds like that is exactly what your problem is.

[HACHI-RYOKU]

Those are some good vids. Thanks Talldude.

[HACHI-RYOKU]

On that diff that you had, who made it? I was thinking about the little screw thing (can’t think of the name right now). If that comes loose or falls out you can get symptoms like this. It will pull to the left because the left tire is getting no power and the right tire is getting power, so it turns like it has tank steering. It will sometimes go straight, but will never stay straight for long.

I added some screw tightener/gap filler to help keep it in place. I even took it a step further and put a small dab of super glue on it. I noticed all my ball diffs having the same problem. Check that little tiny half screw.

It’s worth the effort. A ball diff is much better than a gear diff.

[HACHI-RYOKU]

Swap out the diff. It takes like two seconds. If it’s not that, then check your spider connections. You may have shorted something out.

[HACHI-RYOKU]

You guys are gonna laugh at me.

I put some fets in a Xmod evo. A stack of 2X3. I’m running a plasma-atomic with neo mags in it. The fets get hot. It doesn’t blow the fets, but at one point it melted the solder on some of the fet’s pins and it shorted out with the pin next to it when I slammed into a table leg. This was all on the output side of the 9910’s. The fets didn’t blow. They wanted to but the batteries were running out of juice and I caught the problem early. I fixed it and it’s running like it was before. It still gets hot around that area though, so I lifted the metal motor contacts that touch the top of the fets. I figured that if they are getting hot, then they’re just contributing to the problem. I also replaced the motor wire with longer and thicker wire. The area is still getting hot though. Otherwise the car is fast as hell. It’s AWD and it has the highest stock gear set.

Anybody have any essay on this? I was thinking I might need to reduce the gear ratio……maybe? Anybody else getting this problem?

I’m starting to grow tires of fet stacks. The only ones I haven’t had any problems with in a 1:28 scale car are the ones in my Gen 1. Sad, but true.

[HACHI-RYOKU]

Well, got some new fets in there. Running good again. I took a good look at my blown fets and it looks like the top fet’s pin # 2 on the fets next to the black box wasn’t touching the pin below it very well. I guess it was just sloppy soldering on my part. I picked up an $8, 15 watt iron from rat-shack, which was alot easier to work with than my 30~80 watt butane iron. I took my sweet time and made sure to get them all connected correctly. I put one on at a time and tested it with a volts meter after each one. Now it’s back in the game.

Allready broke of a little bit of the body on the front. Oh-well, what’s a good car without some battle scars, right? This is actually my beat-up body. I picked up a green Takata Dome with the set originally, but I couldn’t bring myself to beat the piss out of that one. I’ll probably do some body work to this one and give it a fresh coat of paint soon to spiff it up some.

Can’t comment enough on those Gandini foams though. Those things rock and there not even getting worn down yet. I don’t like blowing that much dough on tires, but they are worth every penny. I would recomend the soft foams in the back and the medium or hard foams in the front. It makes a little understeer, but it’s better than flipping. This setup is still better than the other tires I’ve tried. You were right PH2T, I’ll never look back. The oil shock is also a must in my opinion.

[HACHI-RYOKU]

Here’s a test you can do. It may or may not work. Touch the antenna to the metal wall and then try to control it. Sometimes this helps. If it does work, you could connect a wire to the wall and the antenna while your racing. Sounds strange, I know, but it could be easier than plastering a wall. You could also try changing the frequency, but sense it sounds like you’re running more than one car, I would assume you’ve at least tried two frequencies.

As far as plaster, in theory it would help. Insulating metal reduces the metals ability to recieve a signal. So, if you covered the wall with plaster, it would let more of the signal go to the car. The problem is that that’s alot of metal and covering it may not solve the problem completely. Covering the wall with rubber could be an option if you want to get crazy with it. Not sure where to start when it comes to covering a wall with rubber though. Is there anything else that is close by that may be interfering with transmitions? Power line right above the shed? Tons of electronics in the shed?

A few other things you could try; Bending the antenna on the car at different angles. Standing at different positions in the shed. Checking the car’s antenna conection to the PCB of the car. Changing the car’s antenna to something else like a solid piece of copper wire (gold wire might be an option too. Not completely sure on that one. The basic idea would be to use a metal that could pic up the signal better than the iron.). If the shed’ds not that big, you could tear it down and put a wooden one up instead.

Not sure which one of these ideas would work the best. Transmition problems can be very unique sometimes.

[HACHI-RYOKU]

They”re a few mm away from the batts. Maybe I”ll wire it or just get an external board.

I’m also kinda wondering if there is a different problem. Most of the wires close to the fets melted a little. I’m wondering if some wires melted together and shorted. I still need to give it a thorough inspection.

Edited by – HACHI-RYOKU on 12 January 2006 14:37:23

[HACHI-RYOKU]

Blew those damn fets today after running it pretty hard for about 1 1/2 hours. The forward fets are crispy critters now. I think the fets are in a bad position. They are too close to the batteries and closed in. They can’t be getting good airflow or anything there. Heat probably builds up easily. Anybody have their PCB’s positioned differently to offer a better position for the fets. Probably should have given them a rest.

Thankfully, it looks like everything else is ok.

Oh, on a side note. The gandinis are awesome. The iwaver ball diff and the oil shocks are very good too.

[HACHI-RYOKU]

Interesting. I wonder if the aerodynamics of it help out.

[HACHI-RYOKU]

The carbon center shaft isn’t gripping the forward pinion well enough. Just a guess. I doubt it’s the motor.

[HACHI-RYOKU]

The carbon center shaft isn’t gripping the forward pinion well enough. Just a guess. I doubt it’s the motor.

[HACHI-RYOKU]

Gandini soft foams, ball diff, bearings and oil shock already ordered. That, and some fets for the Xmod Evo. All from Ausmicro.

A9 tooth pinion is considered low right? It’s the largest stock, but I’ve seen larger.

Antenna straightened. I was enjoying the sweapt look.

You’re not kidding about the ‘real 1:28 scale racer’. I had planned on getting a mini-z first, but a sale on Gen1 Xmods ($25) made me get one of them first. Then I had to wait cause I knew my wife was gonna get me one for Xmas. She also picked me up a Xmod EVO. So now I’ve got one of each. The mini-z blows the Xmods away in speed and control. It’s on a completely different level.

Thanx for the tips. I’ll be doing most of my racing on a waxed clinic floor. Pretty smooth surface. I’m hoping the gandini soft foams will work well on that. I picked up some GPM rubber tires because they were easily attainable. The GPM tires blow nuts. Their 8 degs areabout as stickyas the stock mini-z tires. In fact, I picked up some 8, 15 and 35 degs. They were all pretty much the same. I’ll be using this a little on the road. Mostly for testing purposes. And I would like to take it down to the LHS were they race on Sat. The track there is carpet with a huge straight away. Not a small track. It was made for 1/10. Requires foams though.

[HACHI-RYOKU]

Got it all worked out……..I think.

I’m running a plasma-atomic with neo mags in it. The speed of this thing is rediculous. This is my first mini-z. I was already impressed by it’s performance stock. Now with the 2X3 stack of 7317’s and the plasma-atomic, I’m floored. I use to be so proud of being able to get my gen 1 Xmod to keep pace with my near stock Xmod EVO. Now I don’t know if I’ll ever buy another Xmod.

Anyway, I did have a bit of a problem. While I was running it (for about 5 minutes), it seemed to get a mind of it’s own and ran into a curb. After that it wouldn’t respond. So, I shut it all off and pulled out the batteries. Checked everything inside, but it was all OK. I put the batteries back in and the motor started going while the car was turned off but the fets weren’t getting warm. So, I checked it all again, but everything was fine. Fets and all. I took a break, came back after a bit, put some fresh batteries in and it returned to normal. No problems. I suspect some radio interference, but am not certain as that would not explain the motor running while the car was turned off. I’m kinda clueless to what happened, but I am still enjoying the car. Nothing else has gone wrong.

Anyhow, here’s some pics of the PCB and the car;

[HACHI-RYOKU]

Thanx RC. The input is very much appreciated and makes sence. Been kinda busy with work and the wife. I will get this hooked up soon and let you know.

[HACHI-RYOKU]

Looks good dude. I like the hood. I would get a thin guitar string for the antenna. That would make it more invisible. Plus the range would be better.

[HACHI-RYOKU]

Nice find dude. The lipoly batts look a little overpriced, but everything else is priced ok, so I have a feeling the lipoly batts may be priced right. I use Kokam 145mah lipoly. I rememnber peying alot less for them, but it all depends on the output of those EZ batts. Those look like they would fit better. But the Kokam charger was much cheaper also. I think it was about $60. I’m speaking in US dollars and I got them at “homefly”. You might have troubles trying to get them outside the US from this company. Looks like a good on-line store you found. I’ll probably pick some stuff up from them.

As far as I know, the higher resistance a motor has, the faster it will go. Unfortunately I don’t know the resistance of bit motors, so I have nothing to compare the numbers to.

I say get some of those lipolys and try them out. They can’t be slower than nicads and they’ll almost definately weigh less.

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