ph2t
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dave, you’re correct, the longest RM is still shorter than the MM.
you putting that SLR on a MM chassis? I’m keen to hear how it handles.
the mclaren F1 shell (which I got in this MM RTR) is a great shell for racing, sits low and doesn’t detract from the handling.
The supra is good too. So far it is handling well inside. The real test is outside, but I’m waiting for my concrete to dry after a day and a half of continous bloody rain!!! arghhh!!!!
here’s some closer shots of the rear wheel wells, sorry about the bluryness.
ph2t.
Update time in nelly land….
Ok, first off the bat is my supplier issue. They’ve now finally gotten back to me with a date of two weeks. I was hoping the parts would be in stock by now so I could fullfill my backorders…. It looks to be early Feb now before production starts up again
:evil:.On another note my investigation into an all n-chan MOSFET h-bridge has been succesfull! :smiley16:. Using the MAX628CSA chip I can now drive n-chan MOSFETS where p-chan MOSFETS used to be. The bottom line is that n-chan MOSFETS offer lower on resistances than their p-chan counterparts….
Since I’ve not had parts in stock I’ve done a test rig using some beefy, low ohmage MOSFETs that I’ve reserved for another (large scale :smiley2:) project. The principles are the same though.
Check it out, say hello to Nelly big fella. haha…
This one is going into porkhunt’s MicroRS4 this weekend to beef up a crappy RX/ESC combo unit that is overheating….With a (datasheet) limit of 80A I see this one handling all the 1:18 micro motors out there, no sweat. Testing will prove it, but I beleive it will be OK.
not too shabby….expect v1.4 in the shop soon!:p
ph2t.
and the saga continues…….
Since I’ve now got the servo down pat I decided to tackle the rest of the setup.
Due to space issue you can’t leave the crystal in the default location, it needs to be moved. Most xmod/iwaver conversion just solder the crystal in and then bend it at right angles to make the space. I wanted to be able to change the crystal still so I came up with the following setup:
I then drilled a hole in the crystal plug and “impaled” it on top of a the plastic that comes up from the bottom of the chassis, neat as! lol….
I also, cut out two other parts of the chassis to help guide the iWaver PCB to where I wanted it to go.
To mount the servo I butched a piece off the original plastic and screwed it in it’s original place.
I also put a bit of sponge spacer in the front bracket to help maintain a healthy level of pressure to keep the servo from going anywhere.
Here’s the setup, all rigged up and ready to be finallised..
Have a look at the setup, nice and neat! you wouldn’t tell the difference! lol…
So far, initial tests have shown that she goes very well. I’ve still got many things to do to this setup including a better motor, nelly turbo, li-poly’s, and other goodies shown below!!!
More to come!!
ph2t.
I think I’ve got it now…
I replaced the steering motor with an original TOMY BCG 1.6 Motor.
I’ve noticed a couple of things with this change.
1) In combination with the changed capacitor, I now get servo travel to the full extents of its movement.
2) Before, turning to one side wasn’t as quick/easy as turning the other way. Also returning to centre position was quicker one way than the other. After swapping the motor out to the 1.6 it is now quick and even return on both sides! A lot better!
Now to go mount the bugger…..
ph2t.
hate to get this thread back onto topic but……
Well I’ve done some futher testing to increase the steering throw, so far I’ve not had the greatest luck. I’ve been able to increase the throw by about %20 each way but still it’s not enough to get all the way to the extents of the servo.
What I have found is that on the IW02 pcb the capacitor that effects this steering throw is located in red in the picture below.
The stock value is written on the cap as 684, this is 0.68uF. The value i’ve settled on for the moment is 0.33uF, that’s the cap you see in the pic. If you were to look at the stock cap it is black and slightly bigger than the one in the pic.
After some testing I’ve found that too low a value, ie: < 0.2uF and the steering servo goes to the left and can't be corrected even if you adjust the trimmer pot on the RX PCB or the steering trimmer on the TX.
Too high a value, ie: > 1uF and the steering servo goes all the way to the right with the same issues with trimmer pot correction.
So in the end I think that I’m going to have to have to substitute a spare steering pot from an iwaver into the xmod servo. I dunno yet, I’m going to try adding a resistor in with the xmod pot to see if that helps.
I wanna get this nutted down before I go futher. Betty.k has told me that the whilst the steering ain’t the tightest, it’s enough for the templestowe track. hmm…….. 🙂
more to come….
ph2t.
Edited by – ph2t on 02 January 2005 14:49:14
