| flm maxx chassis brace | carbon fiber | ofna cd | hacker c50 10xl |
 

After many moons of researching, designing, tweaking (still tweaking actually) and waiting, I finally got the chance to start this project of mine.:yipi:

A list of ingredients:

electrics/power

Hacker C50 10XL
Quark 125B with 'custom' heatsink/mount
Dimension Engineering Sport BEC
Li-saver (Mike's version)
Airtronics steering servo (94359)
Airtronics 3ch Receiver FHSS 2.4 GHz MX-3

chassis

Custom carbon fiber upper and lower plates
FLM Aluminum bulkheads
FLM Aluminum chassis brace
Hardcore Titanium skid plates (front and back)
Unlimited Engineering monoblock chassis extension

suspension

Pro-line steering/servo saver
Pro-line suspension arms
pro-line 23mm Velocity wheels with Bow-Ties and Badlands
Unlimited Engineering shock towers
Unlimited Engineering Supermaxx shocks X 4 (blue springs in front and blacks in the rear)
40 Series USE Hot Racing hubs (23mm extension nuts)
Aluminum knuckles

drive train

OFNA modified LX one center diff with carbon fiber mounts (OFNA Spider on the way)
Unlimited Engineering diff ultralite 7.5 housing
Unlimited Engineering drive cups
Hot Bodies Lightning Hardened Differential and Pinion
HPI Savage XL center drive shafts/dogbones
MIP CVDs all around
Pro-line 23mm hex hubs
RC-Monster pinions 14, 16 and 18 (for speed runs maybe)

Okay... have a look see...

The test cuts made from PVC

http://lh6.ggpht.com/_4vPm5E8J5HA/Ss...2/DSC_0012.JPG



http://lh6.ggpht.com/_4vPm5E8J5HA/Ss...2/DSC_0013.JPG



http://lh3.ggpht.com/_4vPm5E8J5HA/Ss...2/DSC_0015.JPG


Carbon cuts... they were/are a bit rough due to the operator not setting up the router to cut through the material slowly (might have been a dull bit too)...
so it ended up with with a whole bunch of burs along the edges.:whip: The best things is, he did it for free... so I will work with it for now.


http://lh3.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0040.jpg


http://lh3.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0041.jpg


http://lh3.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0053.jpg


More to come...

More...


http://lh6.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0060.jpg

Cutting out the parts were pretty easy with a cut off wheel... kept every thing wet to reduce the dust (still used a dust mask and eye protection)

http://lh5.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0064.jpg



http://lh5.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0075.jpg

Had to remove the burs with a knife before sanding

http://lh6.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0077.jpg

The whole thing required some serious sanding (to prevent dust, i used water on the sandpaper)

http://lh5.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0035.jpg

Motor mount

http://lh4.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0037.jpg

Center diff tower upper brace

http://lh5.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0044.jpg

Center diff mounting plate

Screwing it up...

http://lh4.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0048.jpg

I thought these little 'flat-head' screws would work well for the carbon plates

http://lh4.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0052.jpg



http://lh5.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0056.jpg

This close up gives a good idea of the work needed on the edges... I'm going to hit them soon with some emery boards to reduce the distortion.

http://lh6.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0062.jpg



http://lh3.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0063.jpg



http://lh6.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0067.jpg

The 'power pack'

http://lh6.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0068.jpg

The 'power pack' mock up

http://lh5.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0070.jpg


Going to try and do some work on it tonight... Still have a long way to go before it's finished...


Alien

(Stands in amazement) Man that looks GREAT!!! Great job there!!!

Awesome work!!

very nice.

I like the center differential mount

Thanks man... I hope the end product is even better :lol:



Thanks brushlessboy... I had to modify/cut the LX one towers a bit to allow the 14/16 pinions to move close enough to the spur. The CD
will be lifted a bit, because the 52 spurs is a little too close to the chassis brace (made some spacers for that).

Alien

Wow, didn't see it earlier but those are Pro-Line Suspension arms! Nice job! I had a set of those to make my original max wider!

Instantly one of my favorite builds! Can you turn the motor mount around?

Yep!! Coming back with the old school :lol:... I found these on ebay a couple months back.

Yeah, sure... it can be rotated... the mounting plate has slots in stead of holes, so it will allow for adjustments if needed.

Alien

You've got a PM!

Hope you dont get any flex in the motor mount when you hit a hard landing.

Those arms look a heck of a lot like stockers.....what's the diff between them and traxxas fair....?

http://i110.photobucket.com/albums/n...huong/JIZZ.gif

Outstanding work.

I have been thinking about the mount flexing... I won't be doing any big jumps right now, so it should hold for a while... The Pro-line suspension came out along time ago,
and it was a good replacement for the stock arms (still is actually). where strength is concerned, I think they are just as good as the RPMs or even better (not so sure).

:lol: thanks Neil...

Nice job! I love to see the "Homemade" builds and ideas that people come up with. A part of the hobby I like probably the most. This looks like it is going to be real sweet! The flathead screws look nice. Could you recess them into carbon to sit flush or would that take too much away from the strength/integrity of the area?

CF doesn't do well with tapered cross cuts in it, such as you'd get with a countersunk screw. They tend to delam faster when you do that. I'm speaking from an aircraft design standpoint - but I'm sure the same applies here. Not only that, but you'd dull your countersinks so fast you'd probably spend as much on them as you did on the CF plate. That stuff is really hard on bits.

Thanks man... This is really the part of the hobby I love too... I wanted to keep the heads of the screws on top because it adds a little something to the look of the chassis.


Yep... that's correct I did a test counter sink with a spare piece of carbon and it didn't work out so well.

Continuing with the screw up process:

Got a chance last night to make some test fits with the battery/lower plate...


http://lh5.ggpht.com/_4vPm5E8J5HA/St...DSC_0036_1.jpg

Cut down to 1/4 inch, the aluminum bulk braces made very nice little stand offs for the lower plate

http://lh5.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0039.jpg



http://lh3.ggpht.com/_4vPm5E8J5HA/St...DSC_0040_1.jpg

Still using flat-heads to mount the larger carbon parts

http://lh5.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0042.jpg



http://lh3.ggpht.com/_4vPm5E8J5HA/St...DSC_0043_1.jpg



http://lh4.ggpht.com/_4vPm5E8J5HA/St...DSC_0044_1.jpg

The lower plate needs additional work... I can't access 2 of the 4 mounting for the CD (might just cut slots or big holes)

http://lh4.ggpht.com/_4vPm5E8J5HA/St...DSC_0048_1.jpg



http://lh6.ggpht.com/_4vPm5E8J5HA/St...DSC_0051_1.jpg

I need some M4 screws to make the test fit of the CD with the Savage Shafts and see what kind of adjustments I will have to make to the CD mounting plate

http://lh3.ggpht.com/_4vPm5E8J5HA/St...DSC_0049_1.jpg


More updates to follow, stay tuned :lol:

Alien

Women have retail therapy- blokes have build your own orgasm :yipi:

Are you going to run a single servo or dual for balance? You only have one in the picture.

Yeah, i'll be running one servo... The upper plate was deigned when I was still running the traxxas gear box (two speed).
When it decided to go with the CD, I kept the second mounting position... The receiver will be mounted there when I'm ready to make the final assembly.

Q. Is that a small gap I see between the upper plate and FLM braces, just in front the Monoblock?

The CD mount:

Well I did some work on the CD mount last... Had to make some cuts on the lower plat to facilitate the M4 screws that held the LX one towers to the CD mounting plate. It worked well enough not to look
like an after thought... The Savage XL center drive shafts are just perfect for this project (got them for $8.00 on ebay :lol:).

Have a look....


http://lh6.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0037.jpg



http://lh4.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0039.jpg



http://lh4.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0041.jpg

For the re-build I'm going to add some washers to the bolts going through the mounting plate and chassis brace

http://lh4.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0045.jpg

I did a little test on the motor mount to see if would have any flex... It didn't, but the OFNA CD towers did...:whip: I'm going to keep an eyes open for a pair of aluminum ones...
I have seen them before, but I can't remember where


I did a rough fitting of the electrics (please ignore the masking tape :lol:) to see if everything would work together. Wow!!! I love the hacker c50... It had so much torque when it started...
It looks good so far... No binding and no funny smells :lol:. I slapped on the bow-ties to see how it would roll... Damn... torque!! I did the test with the 18 tooth pinion and it
cogged like crazy, but when it got going... it was not easy to stop.



http://lh3.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0048.jpg



http://lh4.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0052.jpg



More to come

Hi Neil, yes there is a gap... It's on the list of things to resolve when I do the strip down and re-build... the FLM brace and Monoblock are not aligned correctly yet.

Alien

In a word; cool. :yes:

Those nimh's are just for the test right??

Thanks Neil


Ahmmmm... yeah... testing, just for testing. :lol: To be honest... they'll have to be test batts only... I got a chance to throw it on the asphalt today and it was quick,
but they just didn't provide the hacker with the punch it really needs... I'll be getting a couple of these (ZIPPY Flightmax 4000mAh 5S1P 20C) and run them in parallel.

That is freaking amazing.

Thanks man...:yipi:

Hey guys, just an update with some photos. I ran the truck last night on 16 cells with 16/52 tooth combo and it pulled smooth and hard until the Quark started having a little heat issue.
Did not realise it at first when it started cutting out on acceleration and then applying the brake, :whip: but after checking the temps... I decided to stop the run and allow it to cool off a bit...
When I re-started it, all seemed to be fine. I had assembled the ESC on the truck with out running a the heatsink that was there before, so it hod no way of cooling down... I will be fixing this tonight.

The current layout pending a heatsink and fan for the Quark:



http://lh3.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0001.jpg



http://lh6.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0004.jpg



http://lh6.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0006.jpg



http://lh6.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0008.jpg



http://lh3.ggpht.com/_4vPm5E8J5HA/St...2/DSC_0009.jpg


Stay tuned

That's very impressive to look at :yes:

I am a little curious though, why have you chosen to run 5s? With all the weight saving you've done it would still be a rippin' truck and you could use the internal bec on the quark.

Q- Do your flat head screws sit flush? In some of the pics it looks as though they may not be. It could be an optical illusion - or, I thought maybe those screws have a small radius on the inside corner that may be riding on your holes and slots (as in the motor mount).

Thanks man... I often just sit and stare at it too in amazement :lol:.... hmm... I choose 5s because I knew that's what the quark could really handle realistically...
Also, I saw a vid on youtube of a 10xl running 5s (can't find it again though) and it was moving quite nicely around the track... I have seen other 5s setups with similar KVs
getting really good results. I'm not sure what kind of performance I would get from 4s.... Maybe I'll try a 12 cell pack to see how it rolls and give you some feedback.

From the speed calculator:

5s with 14 pinion

Differential Ratio: 4.3
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 52
Pinion Tooth Count: 14
Total Voltage: 18.5
Motor KV: 1624
Tire Diameter (inches): 5.65
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor Coil Resistance: 0
Spur/Pinion Ratio: 3.71 : 1
Total Ratio: 15.97143 : 1
Tire Circumference (inches): 17.75 inches (450.85 mm)
Rollout: 1.11:1
Total Motor Speed: 30044 RPM
Vehicle Speed: 31.62 mph (50.79 km/h)
Effective KV Value: 1624
KT constant: 0.83 oz-in/A

5s with 16 pinion

Differential Ratio: 4.3
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 52
Pinion Tooth Count: 16
Total Voltage: 18.5
Motor KV: 1624
Tire Diameter (inches): 5.65
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor Coil Resistance: 0
Spur/Pinion Ratio: 3.25 : 1
Total Ratio: 13.975 : 1
Tire Circumference (inches): 17.75 inches (450.85 mm)
Rollout: 1.27:1
Total Motor Speed: 30044 RPM
Vehicle Speed: 36.14 mph (58.05 km/h)
Effective KV Value: 1624
KT constant: 0.83 oz-in/A

4s with 14 pinion

Differential Ratio: 4.3
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 52
Pinion Tooth Count: 16
Total Voltage: 14.8
Motor KV: 1624
Tire Diameter (inches): 5.65
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor Coil Resistance: 0
Spur/Pinion Ratio: 3.25 : 1
Total Ratio: 13.975 : 1
Tire Circumference (inches): 17.75 inches (450.85 mm)
Rollout: 1.27:1
Total Motor Speed: 24035.2 RPM
Vehicle Speed: 28.91 mph (46.44 km/h) :whip:(not very impressive)
Effective KV Value: 1624
KT constant: 0.83 oz-in/A


Yes they do... the little corner are sitting in the holes and the heads are flush with the surface of the carbon (the holes are just over 3mm).

Thanks, I didn't know that about CF.

Beautiful work man. Side note- whenever I countersink CF it works fine, is it possible that your countersink bit is dull?

Thanks man... regarding countersinks... I believe the problem I had was that the wrong tools were used to make the countersinks...
A drill bit just doesn't 'cut' it... and I didn't have access to a countersink tool at the time. Recently though, I did find that an abrasive
Dremel tool worked very well... It didn't cut into the carbon, but in stead, it grinds the material away smoothly and reduces the chances of delamination.

You need to make the $7 investment into a countersink bit then :lol:

http://www.dynenco.net/countersink_f...ountersink.jpg

yeah... I guess so:lol:, but I really prefer to stick with the abrasive tool for now.

It continues... I built a little bracket for the heatsink to be bolted to that would fit on the upper plate that didn't appear too intrusive on the design...

... have a look see...


http://lh6.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0194.jpg




http://lh6.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0197.jpg



http://lh4.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0198.jpg



http://lh5.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0201.jpg



http://lh4.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0203.jpg



http://lh3.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0207.jpg



http://lh6.ggpht.com/_4vPm5E8J5HA/Su...2/DSC_0209.jpg



I took the truck to my office parking lot yesterday to put it through passes... I loved the way it performed... it was well balanced and stable despite the surface being wet from a down poor.
I did most of the testing with 16 cells and 14/52 setup... The center diff worked well in keeping the front end on the ground... It just pulled hard through out the rpms until the 14 pinion gave in...
The motor mount screws were loose, so the meshing got messed up. I changed it out for a 16 and tested it on 5s... All I can say is... :surprised:WOW!!! The hacker came alive...
Keeping the front wheels on the ground was no longer easy (BTW I am using 50K in the center diff). Needless to say, the front tyres are ballooning like crazy now...

Despite all the fun, I'm still a little concerned about the temps... the motor went to the high 160s and esc was floating around 135/140... I might be going back to the 14 pinion
(need to order new ones) to lower the temps on the esc and add a little fan on the motor to try and keep it cooler.



More to come... I hope.

Maybe some thermal grease between the esc and heatsink?

If 14t is good, but 16t awesome, maybe try a 15t- split the difference as it were? Sounds like its working awesomely either way :yes:

Hey Neil, I'll get some thermal grease this weekend to see what kind of a difference it will make. Yep:yes:, the 15 pinion will be a good choice too... I'll send Mike my order later today.