View Full Version : How to - 12s T-Rex 600 Setup On A Budget.
How many are doing the 3rd bearing upgrade as part of the 12s project. It looks like you have to buy the bearing blocks in pairs am I correct?
I'm going to add them. If they are of no use, they surely do not hurt. Just from thinking about the forces that might occur, I feel it's better to have this in place.
BPINE
12-21-2009, 09:55 AM
You have to buy the three stock plastic bearing blocks but would have two spare bearings for the metal bearing blocks.
We have seen many polls regarding the installation of a third bearing block.
Sorry to have to hash through old info but why don't you buy the metal bearing block to add as a third?
rceccleston
12-21-2009, 10:08 AM
Sorry to have to hash through old info but why don't you buy the metal bearing block to add as a third?
Because the third bearing block uses a smaller bearing.
BPINE
12-21-2009, 05:08 PM
I have been reading this thread so long I forgot to go back to the first page where all my questions have been answered, Ok now I really feel like an idiot. :o
ferret30
12-21-2009, 07:27 PM
Someone mentioned here or on another thread that if you get a Scorp 4025-630, to make sure you got a 6mm shaft rather than a 5mm. I haven't been able to find one online yet. Any leads?
thayghetucsb
12-21-2009, 10:34 PM
Someone mentioned here or on another thread that if you get a Scorp 4025-630, to make sure you got a 6mm shaft rather than a 5mm. I haven't been able to find one online yet. Any leads?
i believe whichever shop that sells 4025-630 can get u either one with 5 or 6mm shaft. you just have to ask them. if not in stock they can order for you.
Chanq
12-22-2009, 02:40 AM
Another pinion question. I to am planning to go 12S and I already have the CC85HV. My bird is V-barred and I'm looking for an headspeed around 1900 rpm. Motor will be the Scorpion 4025-630. Using the various HS calculators on the web I find that using stock gear and a 12T pinion I will get a HS around 1900 but that is at 100% throttle. Since I want to use the governor it should be 1900 at ~80% which would need a 13T pinion.
However I see most people use a 12T pinion with this setup. Is this because you guys aren't using the governor? Of course the calculators aren't spot on but they give a quite good indication of what I can expect. They don't take into account though that the bird is flybarless.
What would you do?
khermit
12-22-2009, 05:05 AM
i believe whichever shop that sells 4025-630 can get u either one with 5 or 6mm shaft. you just have to ask them. if not in stock they can order for you.
Yeah, you have to order a 6mm replacement shaft seperately. They are easy to change, just 2 screws at the bottom and tap it out.
Highly recommended to use a 6mm shaft. I have a 5mm broke on me during flight.
traeside
12-22-2009, 12:42 PM
[QUOTE=rceccleston;1725169]You'll need the Scorpion 4025-630kv as the stock Align is only rated at 6s with high amps.
Okay stupid question but in looking at the 4025-630 or any of the 4025's for that matter how do i tell that they are rated for 12S?
ferret30
12-22-2009, 01:20 PM
[QUOTE=rceccleston;1725169]You'll need the Scorpion 4025-630kv as the stock Align is only rated at 6s with high amps.
Okay stupid question but in looking at the 4025-630 or any of the 4025's for that matter how do i tell that they are rated for 12S?
I believe the 630 is the KV rating, so multiply 630 by the voltage (12 * 4.2) and you get motor RPM. Then multiply that by the pinion tooth count and divide by main gear tooth count to get headspeed.
630KV * 12S * 4.2V * (12 / 170) = 2241
Something like that. A 10S setup would require a higher KV motor, and so on.
traeside
12-22-2009, 01:21 PM
Okay i see it on Scorpion's website but why wouldn't heli direct have that on there? it appears to be the only line they left out.
traeside
12-22-2009, 01:22 PM
i would expect that answer out of you Ferret. stop trying to make me do math. LOL :YeaBaby:
rceccleston
12-22-2009, 02:35 PM
Someone mentioned here or on another thread that if you get a Scorp 4025-630, to make sure you got a 6mm shaft rather than a 5mm. I haven't been able to find one online yet. Any leads?
Typically so you could use the cheaper Align pinions.
However, it would cost more to purchase a replacement 6mm motor shaft and an Align 12/13T pinion.
rceccleston
12-22-2009, 02:52 PM
Another pinion question. I to am planning to go 12S and I already have the CC85HV. My bird is V-barred and I'm looking for an headspeed around 1900 rpm. Motor will be the Scorpion 4025-630. Using the various HS calculators on the web I find that using stock gear and a 12T pinion I will get a HS around 1900 but that is at 100% throttle. Since I want to use the governor it should be 1900 at ~80% which would need a 13T pinion.
However I see most people use a 12T pinion with this setup. Is this because you guys aren't using the governor? Of course the calculators aren't spot on but they give a quite good indication of what I can expect. They don't take into account though that the bird is flybarless.
What would you do?
With 12s Turnigy 3000Mah 30/40c packs (http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9489&aff=97114), at 100% throttle on 12T, my headspeed peaks at 2150rpm in fixed end points.
Personally, I run in fixed end points as there is minimal bogging on 12s, no aggressive amp peaks resulting in longer flight times.
Due to the 5% tolerances in manufactures kv ratings, the Castle Creations software typically results in over gearing and less efficient.
To achieve optimal gearing in gov mode, it is recommendable to taco the head speed at 75% / 85% throttle and change gearing for desired head speed.
rceccleston
12-22-2009, 02:53 PM
Yeah, you have to order a 6mm replacement shaft seperately. They are easy to change, just 2 screws at the bottom and tap it out.
Highly recommended to use a 6mm shaft. I have a 5mm broke on me during flight.
Still using the original 5mm shaft with nearly 200 flights. :YeaBaby:
rceccleston
12-22-2009, 02:54 PM
[QUOTE=rceccleston;1725169]You'll need the Scorpion 4025-630kv as the stock Align is only rated at 6s with high amps.
Okay stupid question but in looking at the 4025-630 or any of the 4025's for that matter how do i tell that they are rated for 12S?
Scorpions website. (http://www.scorpionsystem.com/catalog/motors/hk40_kits/compare/?p4=203&p5=200&p6=204&p7=237)
rceccleston
12-22-2009, 02:57 PM
[quote=traeside;1727928]
I believe the 630 is the KV rating, so multiply 630 by the voltage (12 * 4.2) and you get motor RPM. Then multiply that by the pinion tooth count and divide by main gear tooth count to get headspeed.
630KV * 12S * 4.2V * (12 / 170) = 2241
Something like that. A 10S setup would require a higher KV motor, and so on.
I believe manufactures have a 5% tolerance on their kv ratings.
rceccleston
12-22-2009, 02:58 PM
Okay i see it on Scorpion's website but why wouldn't heli direct have that on there? it appears to be the only line they left out.
Scorpion added this information to their website within the past 6 months.
ferret30
12-22-2009, 03:00 PM
[quote=ferret30;1728006]
I believe manufactures have a 5% tolerance on their kv ratings.
Good point. I just wanted to show the connection between the 630 number and how that makes it suitable for a 12s setup.
rceccleston
12-22-2009, 03:22 PM
[quote=rceccleston;1728196]
Good point. I just wanted to show the connection between the 630 number and how that makes it suitable for a 12s setup.
Can't fault your theory.
ferret30
12-22-2009, 04:19 PM
Can't fault your theory.
I know there's something missing since it doesn't really match up with the headspeed calcs I've used, but I guess it's okay for rough estimation of the right KV value. The good calcs probably use a lower per cell voltage than I did too (12V?). Maybe I'll go look and see if I can find an actual non-pulled-from-thin-air formula somewhere. :)
rceccleston
12-22-2009, 04:27 PM
I know there's something missing since it doesn't really match up with the headspeed calcs I've used, but I guess it's okay for rough estimation of the right KV value. The good calcs probably use a lower per cell voltage than I did too (12V?). Maybe I'll go look and see if I can find an actual non-pulled-from-thin-air formula somewhere. :)
Readyheli's headspeed calculator (http://www.readyheli.com/Online_Headspeed_Calculator_s/81.htm) isn't too bad.
ferret30
12-22-2009, 04:39 PM
Readyheli's headspeed calculator (http://www.readyheli.com/Online_Headspeed_Calculator_s/81.htm) isn't too bad.
That's the one I was using to sanity check my work. Here we go:
Estimate Head Speed = (Motor kv * Battery Voltage /(Main Gear /Teeth of Pinion)) * Efficiency Rate
So I was leaving off the efficiency rate...
dfrazier
12-22-2009, 04:43 PM
[quote=traeside;1727928]
I believe the 630 is the KV rating, so multiply 630 by the voltage (12 * 4.2) and you get motor RPM. Then multiply that by the pinion tooth count and divide by main gear tooth count to get headspeed.
630KV * 12S * 4.2V * (12 / 170) = 2241
Something like that. A 10S setup would require a higher KV motor, and so on.
If I am not mistaken the kV of a motor is rated at no load. It will be a little lower rpm when under a load.
adroc3905
12-22-2009, 06:21 PM
Couple of quick questions....BTW very informative thread. :thumbup:
Any thoughts on where I can purchase the nylon bolts used on the LG?
I have the Futaba S9252 servos on cyclic. Since the speed and torque are lower, compared to the DS610's, will I still be ok for moderate 3D?
Is the stock Scorp motor bullets that come installed on the 4025-630 sufficient for the CC85 HV connection?
Is 12T sufficient or is 13T better? I want someting I can grow into rather than upgrade later.
When you speak of firmware v2.16, is this something that is on the CC program link disc?
Sorry for all the questions but I want to make sure I build it right the first time.
Thanks in advance.