Wish this would be part of everyone's reviews. I see soany people just blindly adding weight and doing the same thing on every single truck they get and not taking into account actual physics. Great vid.
Great idea Josh. I have stuck a three gear and vanquish hurts dig in mine but yet to make sure body still fits but the VFD is even a better idea. Let us all know what u come up with. Thanks
So good. It's interesting to thing about where the CoG lands and always hard to figure out from rig to rig. And then to think about un-sprung weight and its effects on the CoG and performance.
I moved the stock shocks down to the links mounts and wider wheels and it’s a much more stable truck just doing that. Very interested in seeing what you do, I really like this rig.
It's always great to hear from Josh. I'm hoping to see you create a 3D dash and print something for that back seat area. Outside of those 2 visual issues, that vehicle is extremely impressive when scene in person, especially in that color. Takecare !
I would definitely be interested in seeing the vfd transmission swap it be cool if that's easy enough to do id love to do that as well love the cj but agree with ur statement with motor being so high.
Excellent teaching tool Josh! Thanks for taking the time to demonstrate this concept and provide clear instruction on how to improve our RC experience!
Very cool method of finding the COG. I have corner scales and use the Longacre Racing trigonometry method of finding COG. If you take one more photo with a string attached to a corner of the bumper you could also see the left right balance point. I would say this string method is good for ballpark estimates as having the shocks fully extended is going to severely throw off the COG.
Absolutely it does. But any method of bench testing will have dynamics that aren’t accurate during running so it still gives you one of the most easily repeatable tests.
@@HarleyDesignsInc Totally agree. Driving is the real proof. I have just been surprised myself by how much small changes to suspension setup can affect weight shifts.
Idea to make this easier. Hang a long second sting behind the hanging rc and line the strings up for the pic. So you have a reference line on either side.
Great video !!! I’ll be checking all mine just to see if there is a correlation between center of gravity and fun factor… I just trail run… no hills or rocks to craw here
I’ve wanted to swap a Vfd twin into my gladiator ever since I put the OD servo on my Phoenix. I love being able to trail it to the crawl spot and then flip that OD on and watch it work on some hard lines.
Interested to see what you do to this truck. I got mine a few days before Christmas. I'm probably gonna try some of your mods! Love the technical info. Keep it up!
Great video description, been trying to thing of a desk top rig to put small scale race cars and truck on for a while that would be able to do the same sort of thing, some sort of adjustable pendulum style thing is what im thinking but haven't got it figured in my head yet.
Interesting! I’ve done CG plenty of times on RC Planes and Helis, but never considered how it would be done on a car. Well, time to find out the CG of every single car I have haha
@@HarleyDesignsInc Well usually the ideal C of G range is specified by the manufacturer, measured aft of the leading edge of the wing. I usually balance the plane on my finger tips, or rig up a stand, and move the battery around until it sits level on the cg mark.
Would you look at that. It's just like full size trucks where we use cam or crankshaft as rough estimate for COG height. For anyone looking to get more precise, the KevinWilsonSBC videos are awesome.
He does make some good tech videos. However I wouldn’t say his method would be more accurate for RC. For RC we have the benefit of being able to do things much easier ways that take a lot of outside factors out of the equation.
@@HarleyDesignsInc oh its for sure more accurate. Seeing as how it's the SAE method used by plenty of engineers, chassis builders and tuners. If that additional accuracy has any use for RC, probably not.
what fun things are you cooking for this beast? I snagged one same color and now I'm wanting to make it my own. It Definity preforms better then the early bronco did out of the box. the torque twist is less.
My plan is to do a transmission swap, new wheels, tires, possibly axles, and all the electronics. So it will be a very different truck in the end I'd say.
@@HarleyDesignsInc make it times 2 cause ill need parts hahaha cant wait to see what ya cook up. I took it out to my spot today and was surprised it did as well as it did. I feel some heavier wheels will help but the tires werent to bad.
curious what the benefit of having the pinion/spur being on the opposite side of the motor in the VFD transmission. As far as I can tell, VP are the only ones doing this, and it can result in difficulties with motor fitment.
Simple but useful info! I wonder - if you wanted to see where the balance was left to right and front to rear, could you hang it from the end of each wheel and look at it from the bottom, then draw the lines and see where they intersect front to rear and left to right?
Man you need to have a light truck and with the Vq transmission that weights a lot u cant get that. Its for no use a 4 kg truck with low cg vs a 2 kg truck with low cg
Density of nylon is around 1.2 g/cm^3 vs the titanium which is around 4.6 g/cm^3. So Titanium would be 3-4 times heavier. Granted, you could try to use less material but in the end you would likely be quite a bit heavier.
The rollbar from the TWS VTG80 , has me thinking it would be right about the same if not less, (if in titanium). weight wise due to the amount of material that would not be used compared to the current cage. But then again, sizing of the rods might just make it the same amount... i'm thinking that i'd rather have the simple cage than the Genright style and am now im just trying to justify making a titanium cage for myself without going 4x overweight ! @@HarleyDesignsInc
Making the guess: it is in the middle of the our planet👍 Your cap Personally I don't care about COG of my rigs. The only thing I did with one of them is playing with weight bias (front/rear).
Besos, Musk, Branson... all spending hundreds of millions to get to space. Here I am, convinced Josh could get us there on a weekend with a gift card from injora and rc4wd.
Kinda defeats the purpose to spend over $5 hun plus on an Axial to tear a perfectly good 2 speed/dig transmission out of it to install a $150 dollars or more for a Vanquish transmission and files. So you gain a lil lower weight but then you lose all that up front weight over the wheels the way Axial designed it. considering the Vanquish motor is nearly a motor length behind where the axial motor sits. The Axial motor sits nearly over the front wheels, the Vanquish tranny puts the motor nearly behind the front wheels. Just not so sure the trade-off is worth the time and $$.if you want a Vanquish just buy one, if you want an Axial buy it.why destroy a perfectly good design for no real gain. To me it's a trail crawler not a comp rig. Install shorter axial shocks w/ 65wt oil and add brass down low is all it needs.
The VFD trans is a better design in terms of COG, and it's what is in most of my trucks because of it. I just want this great looking truck to perform as well as my others!
I don't buy it. - at least there's more to it than that. Weight locations are a big part of the center of gravity, which is why people remove mass from up high and add it down low with brass.
And any change made, will effect the COG and will be reflected in this test. This is just a simple method of finding exactly where the COG of an item is.
This test IS measuring the weight balance. Instead of using a fulcrum (think teeter-totter) it is measuring how mass twists around the anchor point of the string. It’s a bit like a boat sitting in water. Shift a weight left or right, forward or backward, and the boat will tilt different directions with the water line indicating the balance plane. Make any weight changes to a truck (e.g., adding brass to the front axle) and the lines projected by the string will change to indicate the new COG location. In Josh’s photos, half of the mass is always to the left of the string and half is always right of the string. The point where the lines theoretically intersect is the COG.
Wish this would be part of everyone's reviews. I see soany people just blindly adding weight and doing the same thing on every single truck they get and not taking into account actual physics.
Great vid.
I’ve been wondering how to do this. Thank you!
Happy to help!
That was the simplest way I have seen to find the COG. Thanks, always get great info from you.
Great idea Josh. I have stuck a three gear and vanquish hurts dig in mine but yet to make sure body still fits but the VFD is even a better idea. Let us all know what u come up with. Thanks
its not a better ideea, u should go with a outrunner combo and a dlux trans or a Grind trans from ProCrawler ... fhe vfd ain't sh**
Great information. Never thought of it doing it that way.
I swapped a vfd into my 10.3 gladiator. Made a world of difference
Great demonstration Harley!!! I just picked my CJ7 today. This will help with mods!!! Thanks man!!!!🤘🤘🤘
His real name is Matt 😂
@@redndeyes 🤣🤣🤣 I know but I always call him Harley or that dude with the beard
Stubby revolver and am32 esc. Fixed the motor problem!
That definitely would help, but it's still weight up high, relocating everything and combining the efforts will make it even better.
Hop on that vfd conversion....you'll be a God amongst men. My CJ is waiting, my VFD is waiting and the WORLD is waiting!!!!!
Great video Josh. Given me a lot of information to apply to my six crawlers. Thanks!
So good. It's interesting to thing about where the CoG lands and always hard to figure out from rig to rig. And then to think about un-sprung weight and its effects on the CoG and performance.
Nice to have this properly explained for once, great video, thanks, Josh!
COG is not what I thought you were talking about based on the intro... Nice vid...never thought of that method before.
I moved the stock shocks down to the links mounts and wider wheels and it’s a much more stable truck just doing that. Very interested in seeing what you do, I really like this rig.
It's always great to hear from Josh. I'm hoping to see you create a 3D dash and print something for that back seat area. Outside of those 2 visual issues, that vehicle is extremely impressive when scene in person, especially in that color. Takecare !
I would definitely be interested in seeing the vfd transmission swap it be cool if that's easy enough to do id love to do that as well love the cj but agree with ur statement with motor being so high.
I am really looking forward to watching this build series!
Excellent teaching tool Josh! Thanks for taking the time to demonstrate this concept and provide clear instruction on how to improve our RC experience!
Quick, easy method! Not exact but then, close enough. Thanks! 👍
What a great little lesson. Thanks for sharing this little bit of knowledge with us. 🙏👍.
Very cool method of finding the COG. I have corner scales and use the Longacre Racing trigonometry method of finding COG. If you take one more photo with a string attached to a corner of the bumper you could also see the left right balance point. I would say this string method is good for ballpark estimates as having the shocks fully extended is going to severely throw off the COG.
Absolutely it does. But any method of bench testing will have dynamics that aren’t accurate during running so it still gives you one of the most easily repeatable tests.
@@HarleyDesignsInc Totally agree. Driving is the real proof. I have just been surprised myself by how much small changes to suspension setup can affect weight shifts.
This gave me flashbacks of my vehicle dynamics class in college! 😂
Yes please follow-up with this.
Awesome and easy. You Joshed this one. Now I can't wait to check the COG on all my trucks. Thank you.
Idea to make this easier. Hang a long second sting behind the hanging rc and line the strings up for the pic. So you have a reference line on either side.
So simple and very helpful. Thanks. 👍
Awesome vid Josh...will tune in
I would love to see the video when you install the vfd in! Definitely think I want to do that to my early bronco!!
Good idea on the video. It would make a good series.
Great video !!! I’ll be checking all mine just to see if there is a correlation between center of gravity and fun factor… I just trail run… no hills or rocks to craw here
I’ve wanted to swap a Vfd twin into my gladiator ever since I put the OD servo on my Phoenix. I love being able to trail it to the crawl spot and then flip that OD on and watch it work on some hard lines.
Great video. Probably would have been to expand and show knowing where that point is will allow you to see when you vehicle is about to roll over.
I'd guess 2. We'll I was wrong, thanks for sharing this information.
Interested to see what you do to this truck. I got mine a few days before Christmas. I'm probably gonna try some of your mods! Love the technical info. Keep it up!
On my full size Jeep TJ it would be #2 because of the engine location. On the Axial I'd say #3
Guess I’ll be dangling my trucks with strings for the next 3 hours
😂😂❤
I love that CJ, sadly I can't do an RTR, monetarily it makes no sense to me. I will wait for the body to be sold separately and then build it my way.
Thanks for another great video. Good information.
Great video description, been trying to thing of a desk top rig to put small scale race cars and truck on for a while that would be able to do the same sort of thing, some sort of adjustable pendulum style thing is what im thinking but haven't got it figured in my head yet.
Interesting! I’ve done CG plenty of times on RC Planes and Helis, but never considered how it would be done on a car. Well, time to find out the CG of every single car I have haha
I'd like to hear how you prefer to do it on planes, something I've never done except in video games :)
@@HarleyDesignsInc Well usually the ideal C of G range is specified by the manufacturer, measured aft of the leading edge of the wing. I usually balance the plane on my finger tips, or rig up a stand, and move the battery around until it sits level on the cg mark.
Ok this helps lot and I understand the concept lot better definitely need to do this to my scx24
Would you look at that. It's just like full size trucks where we use cam or crankshaft as rough estimate for COG height. For anyone looking to get more precise, the KevinWilsonSBC videos are awesome.
He does make some good tech videos. However I wouldn’t say his method would be more accurate for RC. For RC we have the benefit of being able to do things much easier ways that take a lot of outside factors out of the equation.
@@HarleyDesignsInc oh its for sure more accurate. Seeing as how it's the SAE method used by plenty of engineers, chassis builders and tuners. If that additional accuracy has any use for RC, probably not.
That was actually very helpful thank you.
Great knowledge and information.
Like button engaged man, good stuff.
what fun things are you cooking for this beast? I snagged one same color and now I'm wanting to make it my own. It Definity preforms better then the early bronco did out of the box. the torque twist is less.
My plan is to do a transmission swap, new wheels, tires, possibly axles, and all the electronics. So it will be a very different truck in the end I'd say.
@@HarleyDesignsInc make it times 2 cause ill need parts hahaha cant wait to see what ya cook up. I took it out to my spot today and was surprised it did as well as it did. I feel some heavier wheels will help but the tires werent to bad.
Definitely quick and easy
Very well done video
Thanks, I definitely learned something new!
I’m going to say it’s going to be 1 or 4 I’m leaning more towards 4 but I’m not sure where the battery sits on these but I’ll go with #4 for COG
Wow informative and entertaining? Starting 2024 off strong!
Awesome stuff
“We all know what it is, but do you actually know how to find it?” For a split second I forgot this was an RC video 😭
Unfortunately I won't be very helpful with any other sort of videos! :)
Got your attention didn’t he? Lol
Great video Josh
The cog has gota be 1 😂 this is how I find my cog on my rigs and works pretty well🤙🏽
curious what the benefit of having the pinion/spur being on the opposite side of the motor in the VFD transmission. As far as I can tell, VP are the only ones doing this, and it can result in difficulties with motor fitment.
Guessing it's 1.
Womp womp!
This is a super cool trick, never heard of it.
Anybody make a brass battery cover plate? Looking to lower the cg on my DX3 transmitter! 😂
This is gonna be good 👍
One newbie question. Do the link geometry or suspension geometry change the COG?
by adding the battery pack to the side doesn't that now throw off the weight balance side to side?
Did you try any truck in 3/4 points and see if it’s close?
Simple but useful info!
I wonder - if you wanted to see where the balance was left to right and front to rear, could you hang it from the end of each wheel and look at it from the bottom, then draw the lines and see where they intersect front to rear and left to right?
Yes thats exactly correct. Its the same method but in a different plane.
Very cool stuff
RC4WD for the win
Man you need to have a light truck and with the Vq transmission that weights a lot u cant get that. Its for no use a 4 kg truck with low cg vs a 2 kg truck with low cg
Would a titanium roll cage weigh less than the plastic?
Density of nylon is around 1.2 g/cm^3 vs the titanium which is around 4.6 g/cm^3. So Titanium would be 3-4 times heavier. Granted, you could try to use less material but in the end you would likely be quite a bit heavier.
Do they make a hollow titanium tube? Maybe that would also cut down on weight if building cage out of hollow tubing
Thats not been something I have been able to find. I have looked for it for sure, although I bet 3/16 titanium tubing would be wild expensive!
The rollbar from the TWS VTG80 , has me thinking it would be right about the same if not less, (if in titanium). weight wise due to the amount of material that would not be used compared to the current cage. But then again, sizing of the rods might just make it the same amount... i'm thinking that i'd rather have the simple cage than the Genright style and am now im just trying to justify making a titanium cage for myself without going 4x overweight ! @@HarleyDesignsInc
Thanks josh.....
Making the guess: it is in the middle of the our planet👍 Your cap
Personally I don't care about COG of my rigs. The only thing I did with one of them is playing with weight bias (front/rear).
👍👍
👍💪🤸♀️🤺🧨💯
3 is my guess
only 4:14 in and my guess is 4!
Besos, Musk, Branson... all spending hundreds of millions to get to space. Here I am, convinced Josh could get us there on a weekend with a gift card from injora and rc4wd.
Now I know how to find the center of gravity, kind of,,,
Do you know how to find the center of the underneath of your truck? Drop a Wrench😉
My Dad never told me where it was. It just guessed😂
Anything is better than that axial transmission.. so changing is a win-win, but why wasre time on an axial? Lmbo jj
Fix your suspensions in drive-position with some tape. This will help to find the real COG
Absolutely would find a more at rest location, although that changes constantly while driving as well so a pinpoint COG is only for reference.
That's for real. Good point of view.
This sounds like learning nerd!
I likey!!!
I thought you were gonna talk about something else us guys are always trying to find. 😅
1
I think I failed math lol
gonna say 4
Kinda defeats the purpose to spend over $5 hun plus on an Axial to tear a perfectly good 2 speed/dig transmission out of it to install a $150 dollars or more for a Vanquish transmission and files. So you gain a lil lower weight but then you lose all that up front weight over the wheels the way Axial designed it. considering the Vanquish motor is nearly a motor length behind where the axial motor sits. The Axial motor sits nearly over the front wheels, the Vanquish tranny puts the motor nearly behind the front wheels. Just not so sure the trade-off is worth the time and $$.if you want a Vanquish just buy one, if you want an Axial buy it.why destroy a perfectly good design for no real gain. To me it's a trail crawler not a comp rig. Install shorter axial shocks w/ 65wt oil and add brass down low is all it needs.
4
🧨🤺🤸♀️💪👍💯😁
first
no one cares
I kinda do im like 50ith I lost count if I were in the first 5 or 6 at least then I'd be good 👍
Good info, but kinda feels like a Vanquish commercial, lol
The VFD trans is a better design in terms of COG, and it's what is in most of my trucks because of it. I just want this great looking truck to perform as well as my others!
@@HarleyDesignsInc fair enough
Thats an axis of gravity, use the Z axis to determine the centre point. A third line will determine the Z axis.
That’s why I specified it’s in one plane.
I don't buy it. - at least there's more to it than that. Weight locations are a big part of the center of gravity, which is why people remove mass from up high and add it down low with brass.
And any change made, will effect the COG and will be reflected in this test. This is just a simple method of finding exactly where the COG of an item is.
This test IS measuring the weight balance. Instead of using a fulcrum (think teeter-totter) it is measuring how mass twists around the anchor point of the string. It’s a bit like a boat sitting in water. Shift a weight left or right, forward or backward, and the boat will tilt different directions with the water line indicating the balance plane. Make any weight changes to a truck (e.g., adding brass to the front axle) and the lines projected by the string will change to indicate the new COG location. In Josh’s photos, half of the mass is always to the left of the string and half is always right of the string. The point where the lines theoretically intersect is the COG.
3
One newbie question. Do the link geometry or suspension geometry change the COG?
It doesn't change the COG. But it works in correlation to the COG to determine the antisquat values and how the truck handles in general of course.
4
3
4