Bl Cen matrix build - Page 3 - RC-Monster Forums

jhautz · 09.27.2008, 01:52 PM

Just a little bit on out outside edge of the cup to make the ring gear fit over it. I actually think I just did it with some sandpaper. It didnt take much at all.

I have a brand new Kyosho center dif here with a 50T gear on it. (It think its a kyosho anyway) Not sure where I got it but it doesnt look like it has ever been used and I have no use for it at this point. PM me if you want it. Not sure if a 50T will work for you or not. But it should drop right into the cen if I rmember right. I'll let you have it very reasonably if you can use it.

lincpimp · 09.27.2008, 01:55 PM

Century make a 9t pinion, but only good for a plastic spur.

BL_RV0 · 09.27.2008, 01:57 PM

Novak also makes a 9t gear:
http://www.shopatron.com/product/part_number=5109/135.0

brushlessboy16 · 09.27.2008, 02:02 PM

Quote:

Originally Posted by jhautz

Just a little bit on out outside edge of the cup to make the ring gear fit over it. I actually think I just did it with some sandpaper. It didnt take much at all.

I have a brand new Kyosho center dif here with a 50T gear on it. (It think its a kyosho anyway) Not sure where I got it but it doesnt look like it has ever been used and I have no use for it at this point. PM me if you want it. Not sure if a 50T will work for you or not. But it should drop right into the cen if I rmember right. I'll let you have it very reasonably if you can use it.

hmmm makes it alot easier and give me more room for gearing, i think ill take it :D

Quote:

Originally Posted by lincpimp

Century make a 9t pinion, but only good for a plastic spur.

what happens if i use metal to metal?

i know that duratrax makes a spiral cut gearset for the raze (very stong i know from expireince) that might fit for diffs

jhautz · 09.27.2008, 02:07 PM

I wonder how that novak 9T ould hold up on steel. I tend to have more issues with steel gears hat are smalle rthan 13T. Even the hardened pinions smaller than that against steel whear out quicker. The angle of the teeth on that small of a gear is the problem.

BB: If you not sure the 66T spur with the 9T pinion will fit on the motor mount you can email mike. Basically you need it to have a minimum of 40mm from the center of the diff bearing seat to the center of the motor shaft in it farthest out positin to get that gearing to work.

Not sure if it will. I think Mike usually designs them to work with the standard gear for the buggy (46T in this case) and the biggest poinion he makes (25T). That would require a minimum of 37.5mm center to center to work. He might put a little extra in there for safety so its possible it might work. Email him and see what he says.

brushlessboy16 · 09.27.2008, 02:12 PM

ughh 66/13 comes to 41.5mm lol just my luck

jhautz · 09.27.2008, 02:20 PM

Are you sure you are using the right front/rear diff ratio? I thought that the Truggy came with 38/11 diff gears on the Cen. The RTR Cen buggy comnes with the 26/9 gears and the pro buggy came with the 38/11 gears, but I thought all of the truggies came with 38/11 which changes your gearing picture quite a bit.

Double check the actual ratio you have. I could be wrong, but mine came with the 38/11 (3.455 ratio) if I remember right.

Quote:

Originally Posted by brushlessboy16

replied :D

Differential Ratio: 2.8888888888888888888889
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 66
Pinion Tooth Count: 13
Total Voltage: 18.5
Motor KV: 2200
Tire Diameter (inches): 5.65
Tire Ballooning (inches): .15
Motor Current Draw: 80
Motor coil Ω: 0.006
Spur/Pinion Ratio: 5.08 : 1
Total Ratio: 14.66667 : 1
Tire Circumference (inches): 18.69 inches (474.79 mm)
Total Motor Speed: 39644 RPM
Vehicle Speed: 47.85 mph (76.86 km/h)
Estimated Adjusted Speed: 45 mph (72 km/h) - 6% loss
Effective KV Value: 2142.92
KT constant: 0.61 oz-in/A
Motor Torque: 0.26 ft-lbs
Final Torque: 3.76 ft-lbs
Final Power: 1480 watts (2 HP)

thats with the stock diffs and spur.
needs a 13t pinion for 45mph. thats doable/

here is with 46t spur
Differential Ratio: 2.8888888888888888888889
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 46
Pinion Tooth Count: 9
Total Voltage: 18.5
Motor KV: 2200
Tire Diameter (inches): 5.65
Tire Ballooning (inches): .15
Motor Current Draw: 80
Motor coil Ω: 0.006
Spur/Pinion Ratio: 5.11 : 1
Total Ratio: 14.76543 : 1
Tire Circumference (inches): 18.69 inches (474.79 mm)
Total Motor Speed: 39644 RPM
Vehicle Speed: 47.53 mph (76.34 km/h)
Estimated Adjusted Speed: 45 mph (72 km/h) - 6% loss
Effective KV Value: 2142.92
KT constant: 0.61 oz-in/A
Motor Torque: 0.26 ft-lbs
Final Torque: 3.78 ft-lbs
Final Power: 1480 watts (2 HP)

would need a 9t for that, pretty sure no one makes a 9t lol

brushlessboy16 · 09.27.2008, 02:22 PM

i just checked tower, says the truggy is 9/26

jhautz · 09.27.2008, 02:24 PM

OK then. I'm probably just not rtemebering right anymore. I'm working from memory here and its not what it used to be. lol

brushlessboy16 · 09.27.2008, 02:29 PM

confirmation, just looked in the matrix assembly manual, it is 9/26

JThiessen · 08:19 PM

Quote:

Originally Posted by brushlessboy16

we do i just wouldnt think that lexan would be structurally sound..

plus i don think any place around here carries lexan

Its plenty strong - just a little on the heavy side. Any Lowes or Homedepot will carry it, and most hobby shops have smaller pieces. Another place to try is one of your local home window dealers. Call around and see if they have any scraps you can dig through - they might let you have it for free.

brushlessboy16 · 09.27.2008, 09:48 PM

i think i have some in the garage, is it possible to fuse the corners somehow?

i remember my grandpa doing it, something with laquer thinner or acetate that fuses them together...

brushlessboy16 · 09.27.2008, 10:10 PM

Well guys im possibly out for the night.. Just got back from a party, ended up playing manhunt, ran head to read with my friend mike (eovnu87435ds) both of us at full speed, my forehead to his temple.

I blacked out, his temple is swollen..

it was all in good fun- im going to go to sleep

brushlessboy16 · 09.28.2008, 10:19 PM

whew, rough night but im back.

I think im going to have a shot at fabricating my own components.

motor mount will be out of 2x2x 1/8th aluminum angle, and battery tray will be from 1/8th kydex plastic, going to try to make a die out of wood to use as a form.

and use another peice of wood as the die to form it.

is aluminum sturdy enough to tap into, or should i use a nut and bolt

lincpimp · 09.28.2008, 11:27 PM

Quote:

Originally Posted by brushlessboy16

whew, rough night but im back.

I think im going to have a shot at fabricating my own components.

motor mount will be out of 2x2x 1/8th aluminum angle, and battery tray will be from 1/8th kydex plastic, going to try to make a die out of wood to use as a form.

and use another peice of wood as the die to form it.

is aluminum sturdy enough to tap into, or should i use a nut and bolt

1/8 al is a bit thin. Go up to 1/4 or 5-6mm. Then you can drill and tap the edges. Kydex makes great trays. I like to use the velcro strap and cut slots in the sides to thread it thru.