ph2t

[ph2t]

OK, I’ve had a lot of success with the Stacked Nelly turbo. I never realised so many people want to run < 20 turn motors!! You're all crazy! haha…

What I’ve found is that whilst stacking the MOSFETS on top of each other was the easy way to go, there’s a few design challenges.

1) If a MOSFET fries, it can be tricky to repair (given the stacked setup) and I may need to destroy a perfectly good MOSFET to get to the fried one.

2) Heating in the stack is additive, ie: MOSFET on top of MOSFET, not MOSFET -> air. Whilst heating isn’t a huge issue (ie: ’cause of high current rating of the turbo), some people run some crazy hot setups (3S lipo + 20turn or 2S lipo + 15 turn, etc, etc…) and I gotta account for that.

3) Stacking MOFSETs is essentially quite a messy job. Takes time to do and time to “tweak”. You need to bend MOSFET pins and the labour (from my point of view) is just too much….

4) I found on a 3S lipoly + 27 turn (plasmatomic) setup that I acutally fried one the copper tracks on the Nelly PCB!!! Yes, a solid 2-3mm copper track just fried under the current load in a 3S lipo + plasmatomic setup (in an AWD EVO running around a parking lot…).

So I’ve now just simply increased the size of the PCB and layed all the MOSFETS out flat!!! A simple change that has increased the size of the Nelly PCB, but it’s still under half the size of the V2.x .

Here’s a pic showing the changes to the PCB. The new Stacked Nelly EVO PCB is on the left, the original Nelly EVO PCB is on the RIGHT.

Notice that the high current copper tracks are a lock thicker in the new design. To do this I had to remove the motor solder pads off the end of the EVO PCB, but that’s no big a deal. As you can see this setup is really intended for all the nutter’s out there with low turn motors, lol…

Here’s another picture showing the orientation of the power wires and the typical 4 signal wires that goto the xmod/mini-z/iwaver RX PCB.

I’m still undecided on the final wiring layout. This will do for now, since I still need to cover the Nelly in the clear heatshrink that Ilike to use, so the wires need to be able to come out each side for this….I’m also experimenting with some custom heatsinks as well…

And here’s a closeup of the Stacked Nelly PCB itself…

Sweeeeeeeeet……

Operating Limits:

Max current: 30A
Max Voltage: 20V (Actual true limit dictated by RX, eg kyosho PCB 7.4V, EVO PCB 11.1V)

This has been tested on a 11.1V 3S Lipoy setup running the MinizWorkshop 15t Motor(running no load). Ran cool with no problems. I will be testing this setup in an EVO chassis soon. Just don’t have time at the moment….

Will be avilable to purchase from my site and others soon!

ph2t.

[ph2t]

OK, I’ve had a lot of success with the Stacked Nelly turbo. I never realised so many people want to run < 20 turn motors!! You're all crazy! haha…

What I’ve found is that whilst stacking the MOSFETS on top of each other was the easy way to go, there’s a few design challenges.

1) If a MOSFET fries, it can be tricky to repair (given the stacked setup) and I may need to destroy a perfectly good MOSFET to get to the fried one.

2) Heating in the stack is additive, ie: MOSFET on top of MOSFET, not MOSFET -> air. Whilst heating isn’t a huge issue (ie: ’cause of high current rating of the turbo), some people run some crazy hot setups (3S lipo + 20turn or 2S lipo + 15 turn, etc, etc…) and I gotta account for that.

3) Stacking MOFSETs is essentially quite a messy job. Takes time to do and time to “tweak”. You need to bend MOSFET pins and the labour (from my point of view) is just too much….

4) I found on a 3S lipoly + 27 turn (plasmatomic) setup that I acutally fried one the copper tracks on the Nelly PCB!!! Yes, a solid 2-3mm copper track just fried under the current load in a 3S lipo + plasmatomic setup (in an AWD EVO running around a parking lot…).

So I’ve now just simply increased the size of the PCB and layed all the MOSFETS out flat!!! A simple change that has increased the size of the Nelly PCB, but it’s still under half the size of the V2.x .

Here’s a pic showing the changes to the PCB. The new Stacked Nelly EVO PCB is on the left, the original Nelly EVO PCB is on the RIGHT.

Notice that the high current copper tracks are a lock thicker in the new design. To do this I had to remove the motor solder pads off the end of the EVO PCB, but that’s no big a deal. As you can see this setup is really intended for all the nutter’s out there with low turn motors, lol…

Here’s another picture showing the orientation of the power wires and the typical 4 signal wires that goto the xmod/mini-z/iwaver RX PCB.

I’m still undecided on the final wiring layout. This will do for now, since I still need to cover the Nelly in the clear heatshrink that Ilike to use, so the wires need to be able to come out each side for this….I’m also experimenting with some custom heatsinks as well…

And here’s a closeup of the Stacked Nelly PCB itself…

Sweeeeeeeeet……

Operating Limits:

Max current: 30A
Max Voltage: 20V (Actual true limit dictated by RX, eg kyosho PCB 7.4V, EVO PCB 11.1V)

This has been tested on a 11.1V 3S Lipoy setup running the MinizWorkshop 15t Motor(running no load). Ran cool with no problems. I will be testing this setup in an EVO chassis soon. Just don’t have time at the moment….

Will be avilable to purchase from my site and others soon!

ph2t.

[ph2t]

nerd…….

[ph2t]

@kero, mine broke in the same place!!! And broke the other day again too! That’s a good tip I will do.

@tada, if you’re racing the AWD outside on concrete then I strongly suggest the cambered knuckles for your next purchase. At least the 3.0 Deg ones.

Also look at wider offset wheels. I use 1.5 on teh front and 3.0 on teh rear.

The camber and the offsets made my AWD usable on concrete. I highly suggest those upgrades mate. Oh and of course a nelly or a spider and a pn SABER motor…..

You can get the spider turbo and the pn saber motor from the ausmicro shop. http://shop.ausmicro.net 🙂 See my sig if you want to get a nelly.

ph2t.

[ph2t]

Motor specs are Large comm, silver comm (on one of them) and really big armatures. Like so big you need to trim the endbell back a bit so it doesn’t rub, lol….

On another note, I’m testing a new version of my Delxue turbo. this version is now using the smaller MOSFET drivers and also a REALLY SMALL SOT-23 5V regulator….. lol….

The 5V reg is very small and also doesn’t have the largest current drain limit so I don’t know long term if I’ll stay with this type or not. I just love the fact that it’s soo bloody small now.

Check out the size of Nelly Deluxe against it’s “competitor” lol…. the v2 by atomicmods.

Just a bit of a size difference! lol

Anyways, teh proof is in the pudding so I gots to test this before I go any futher.

more updates soon….

ph2t.

[ph2t]

1) do both front wheels spin equally?

2) remove the OL diff and inspect it, the gear diff may have crap in it causing it to not transfer the power equall between left and right rear wheels.

3) do the wheels wobble? this can cause the symptoms you describe

ph2t.

[ph2t]

Interesting stuff Merc, it’s great to see you posted some pics mate.

That brushless motor, got any more info on it? What’s the shaft dia?
Gots me interested……

ph2t.

[ph2t]

Unfortunately Graham, the crystals won’t reponsed to a continuity test as you’d like them two. They appear as an open circuit for DC current tests….

You’re best bet is to just get another pair.

In the world of RC, crystals are like Pet Hamsters…..don’t get too attached to them, lol…..

ph2t.

[ph2t]

I’ve had this before with some handwounds mate. What I think is happening is that one of the three commutator lugs (where the armature wire wraps around) isn’t conducting to the wire.

Use a multimeter to check that you have a connection. You can do this by checking for a short between each commutator segment. There should always be a short between each adjacent segment…

Also, remove the neo magnets and brushes and see if the comm spins freely in the bb can. MAybe it’s binding somewhere? Posssbly from not being true or pressure on the comm from being too long for the can? Possible but not probable…..

cheers,

ph2t.

[ph2t]

lol, a bit risky but cool!

but yeah, as kero said! VIDEO!

[ph2t]

lol, good stuff mate!

I know what you mean about the 010’s drivetrain pushing the health of the anima…. I’ve now got a 36t pattern wind motor going in my 010, lots of torque and all I need to do is gear it up to get the speed. It runs at a good temp too! Put about 4-5 packs through it and so far no issues.

flashsp-2 over at xmoding.com built it for me, he’s in the USMC, stationed in japan, does great work at very good prices.

Given the drivetrain load, I really think 36-37 turns motors are at home on the AWD chassis….

ph2t.

[ph2t]

note to self, learn how to drift first before making a vid……

🙂

[ph2t]

There’s an issue with bearings when you build a chassis from the ground up like this.

the 4 differential bearings don’t come with any of the stock parts. You have to source them yourself.

I got the dimensions from the ma-010 data sheet, they’re:

Quote:

ID (d) (mm) : 6.000
OD (D) (mm) : 10.000
Width (B) (mm) : 3.000

So I got some ceramic ABEC quality ones:

http://www.smallparts.com.au/cgi-bin/store/item_info.pl?product=MR106A-ZZS-CB-AF12&alphafile=B=post

Just got them in today. Cost my just under $30USD for four. Yeah, not cheap! But when you look at it, the ATOMIC bearing set costs $37, and you still dont get the 4 diff bearings.

http://www.egrracing.com/mart/product_info.php?cPath=21_82&products_id=776

In fact, it’s quite hard to find the bearings in a full set (inc the 4 diff bb’s).

The official kyosho bearing set doesn’t come with them.

Neither does the PN racing set:

http://www.rckenon.com/public_html/shop2/catalog/product_info.php?products_id=1048

Nor these ones from rcstation.com

http://www.rcstation.com/eshop/catalog/advanced_search_result.php?keywords=bearing&categories_id=342&inc_subcat=1&manufacturers_id=&pfrom=&pto=&dfrom=&dto=&x=0&y=0

So if you wanna build from the gound up these diff bearings need to be sourced from somewhere.

Thankfully you don’t need to buy ceramic bearings like me, you can get them from toyeast for a little of $3 for 5, lol…

http://www.toyeast.com/v3/pdtdetail.asp?pdt_id=A01401037

Can’t wait to try them out….

ph2t.

[ph2t]

Does a bear shit in the woods???? Who’s planning it? Are there any contacts? what’s the timeline??

ph2t,.

[ph2t]

Got my HUDY truer in now and finally did my first set of trued foams….

Check the gallery here:

http://www.ausmicro.com/forum/vbpicgallery.php?do=view&g=42

Just waiting on some more foams from that site I linked earlier. At the moment I only have this set of gandini’s, nothing else 🙁

The challange now is to make an adapter for AWD rims……

ph2t.

[ph2t]

lol, how do you find that setup mate? Did you have any issues with the ATOMIC ball diff?

ph2t.

[ph2t]

Final crap load of ma-010 parts came in redcetly! yeaaaaaaaaah!

Building my own ma-010 from the ground up, staying kyosho in some key areas. I got burnt bad by Pn Racing / ATOMIC part mismatches the first time I got an ma-010 (to the point where I sold it).

This time, things are different. There’s only pics going up , but I’ll detail the parts list soon.

Some highlights….

Kyosho front one-way diff….

ATOMIC ball diff (rear)

KPGC Skyline (Kyosho autoscale model, the painted version of Faze’s)

No guts in it yet, just a rolling chassis. that should be sorted by the weekend. Got a nice, fatty comm, 36t pattern wind flashsp-2 special going in this!

credit cards are good! 🙂

ph2t.

[ph2t]

well, it works!!!! decided to call this one “Nelly Pro”, lol……

Initial testing on the bench shows the newer design to work well. I tested on 4 cells and 2S li-ion (7.2V) and both configs worked a treak.

I’m quite happy with this. It’s a HUGE leap in size savings for nelly, just look at the following pics….

See the new nelly PCB on left vs. nelly deluxe PCB on the right. Some things to note, the one of the left does NOt have the 5V regulator circuit. But still, it’s not hard to figure out that even adding that the area saved is still huge!

In the pic below, I’m comparing other versions of my nelly turbo.

from left -> right:

nelly EVO (aka, nelly v1.2, basic external MOSFET h-bridge)
nelly v1.4 (updated version of v1.3, MOSFET driver on n-chan MOSFETS only)
nelly pro (just made it tonight! MOSFET drivers on all MOSFETS)

So you can see that even with the increase in MOSFET drivers on nelly pro, the amount of room it takes up is comparable with my older nelly v1.3 version which used the larger SO-8 packaged MOSFET driver…..

Here’s a picture of where I typically mount my nelly turbos. As you can see the space is good!

Even though this nelly doesn’t have the 5V regulator circuit, it has the same benchmark setting performance as my premium nelly deluxe model. Just without the 5V regulator circuit. The space savings over nelly delxue are up to 40% – 50%!!!!

I’m really happy with this and the 8-MSOP packages on the MOSFET drivers weren’t hard to solder either, you just need to have a few tricks up your sleeve……

more to come when I test the bugger….

ph2t.

[ph2t]

well, it works!!!! decided to call this one “Nelly Pro”, lol……

Initial testing on the bench shows the newer design to work well. I tested on 4 cells and 2S li-ion (7.2V) and both configs worked a treak.

I’m quite happy with this. It’s a HUGE leap in size savings for nelly, just look at the following pics….

See the new nelly PCB on left vs. nelly deluxe PCB on the right. Some things to note, the one of the left does NOt have the 5V regulator circuit. But still, it’s not hard to figure out that even adding that the area saved is still huge!

In the pic below, I’m comparing other versions of my nelly turbo.

from left -> right:

nelly EVO (aka, nelly v1.2, basic external MOSFET h-bridge)
nelly v1.4 (updated version of v1.3, MOSFET driver on n-chan MOSFETS only)
nelly pro (just made it tonight! MOSFET drivers on all MOSFETS)

So you can see that even with the increase in MOSFET drivers on nelly pro, the amount of room it takes up is comparable with my older nelly v1.3 version which used the larger SO-8 packaged MOSFET driver…..

Here’s a picture of where I typically mount my nelly turbos. As you can see the space is good!

Even though this nelly doesn’t have the 5V regulator circuit, it has the same benchmark setting performance as my premium nelly deluxe model. Just without the 5V regulator circuit. The space savings over nelly delxue are up to 40% – 50%!!!!

I’m really happy with this and the 8-MSOP packages on the MOSFET drivers weren’t hard to solder either, you just need to have a few tricks up your sleeve……

more to come when I test the bugger….

ph2t.

[ph2t]

Dunno if it’s smart or not but I’ve been investigating smaller mosfet driver IC’s. These are in a package type that are bloody small. Try 8-MSOP and 8-TSSOP out on for size, lol….

The 8-MSOP is the smallest one on the right, foreground. The largest one there is the typical SO-8 package that I’ve been getting my MOSFET drivers in. The 8-TSSOP is the one on the left, foreground.

Why do this? Just part of the fun and challenges of getting nelly small as possible. I only use MOSFET drivers now in my deluxe version. But I’m thinking of doing a purist sorta design just for mr02/ma-010 which is where it’s at in 1:28 land these days….

I’m trying out UCC27324DGN and TPS2812PWR, both from Texas Instruments, http://www.ti.com. I just got my samples in a few days ago so I’m itching to try them out! Their specs are similar to the ones I currently use and they have comparable operating voltage ranges as well.

The challenge of soldering these parts to the PCB is huge! I’ve done it before years ago on my knight rider lights circuit for Bits, it’s tricky to solder these SOP packages by hand but it can be done! If you’re crazy enough! lol….

Working on the pcb design now, trying to incorporate newer things that I’ve learn’t about PCB making along the way….

cool!

ph2t.

[ph2t]

very nice and clean install ken!

ph2t.

[ph2t]

Is it just me or did the cover sustain a bit of fet fri-age? lol….

http://www.ausmicro.com/forum/attachment.php?attachmentid=156&d=1146472154

ph2t.

[ph2t]

lol, those 7317’s must be like candy…… 🙂

[ph2t]

nah, put in an order about 3 weeks ago for 200 and got them in 7 days…. maybe a particular component shortage? If you need a batch of n’s or p’s due to already commited orders, lol…. let me know , I can send you some up……

[ph2t]

no worries 🙂 lets us know what you find.

ph2t.

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