Summit based fpv torsion crawler

[mulepic]

Hi All,
The summit is an awesome trail truck and driving it fpv is amazing. But for fpv I wanted it to crawl better so I made it into a super crawler. The key was keeping the weight down b/c I was going to be adding the fpv gear. So I decided to use a simple and light torsion chassis using 2" angle aluminum. With this final set up the truck crawls extremely well now. I'll add more details later.



Lots of clearance:

[Decible142]

Looks cool. Can't wait to see some more. Any vids yet?

[mulepic]

Here are some details.
-Final rtr weight is 10lbs, each front tire has 8oz of lead.
-48p 90T spur 12T pinion. I'm using a robinson pinion and a gear from servocity. I would like a longer pinion b/c I don't have 100% engagement.
-Final drive ration is 115:1 in low and 38:1 in high (if my math is correct)
-Video camera and transmitter are powerd by a separate 500mah 3s lipo
-Car is powered by a 3300mah 2s lipo
-I have a lva on the camera lipo and lost rc alarm on the transmitter.
-The pan servo for the camera has been modified for 360 degree rotation
-Now using the Imex rubicon which appear to be better than the LST tires but I need to do more testing

Here are some pictures of the front and rear steering setup along with how I locked out the suspension arms by pinning them to the bulkhead.

[scootertrash]

That' look's pretty good there brotha'.

[mulepic]

Here's a little video of it: http://www.youtube.com/watch?v=FyjYprbg8nU It's my first one so go easy on my I still need to work out the video so it's clearer. My next video will of better terrain and more interesting.

At the end of the video I put it in high gear and do a lap around the yard. Even though the car is very slow, w/ FPV it seems much faster. As FPV you have to pretty much re-learn how to crawl.

[scootertrash]

One of our club's member's now has a mini' cam mounted apond his rig' - and I fixing to get myself one of those keychain size mini' cam soon as well - they seem to work great' - are add some more fun to driving in fpv' mode as well' - Scoot'er.

[boldercrawler]

That's a great start mulepic, a lot easier to watch than a faster rc truck. I like how you can pan around and look at the rear wheels when your in the rocks.

Nigel

[johnnyh66]

Hey Mulepic, did you start w/a stock Summit or just buy the trans?
If stock, are you using the stock Titan 775 Summit motor?
What did the stock Summit weigh vs. the new set up?

I know you changed the gear ratio from the stock 70:1/25:1.
It would have moved faster in high as stock right? Was there a reason for down gearing it? I can see the reason for the low gear going from 70:1 to 115:1.

Sorry for all the questions but I would really like to give something like this a go.
I'm really interested in mixing the stock high ratio 25:1 (or faster) and your super low 125:1... seems the best of both worlds!

[mulepic]

I've actually never bought a stock summit but I pieced together 2 of them. But I did buy a slayer, and that's how it started. I converted the slayer to a summit by buying the summit drivetrain and suspension pieces. The summit pieces I used for this build are: 6 half shafts, diffs, bulkheads, suspension arms, pushrods, tierods, tranny, motor plate, and a few misc. pieces. You could save money by using the slayer bulkheads and diffs and jb weld the diffs so they are locked.

The gearing is limited by the tranny, it offers a 3:1 low:high ratio so I used the largest spur and smallest pinion I could find b/c I'm using a smaller 540 (novak ballistic 21.5T) sized motor for a large crawler with large tires. So you'll need to find the ratio that works for you. With a larger motor you could use higher gearing. When using FPV the car is extremely fast for crawling.

[dbrad]

Awesome. I've been waiting for someone to do this.

After seeing all of the e-maxxes that have been turned into crawlers by cannibalizing the chassis and locking the axles, I thought the summit would be even better.

Can we see some more pics of the chassis and how it connects to the axles?

I'm looking forward to seeing how this works out for you.

[norbyx]

I just don't get it... why would you compleately change the car.... for that matter just get some clod axles and do yourself the stick crawler you wanted. I might be wrong in thinking that every crawler has it's sience and I think that the summit is good just the way it is... If a want a more capable crawler I just get something else... I might be wrong. But considering also the value of a summit you can for sure sell it and get what you want, and by making this mod I doubt that It would keep it's value...

[mulepic]

Originally Posted by norbyx

I just don't get it... why would you compleately change the car.... for that matter just get some clod axles and do yourself the stick crawler you wanted. I might be wrong in thinking that every crawler has it's sience and I think that the summit is good just the way it is... If a want a more capable crawler I just get something else... I might be wrong. But considering also the value of a summit you can for sure sell it and get what you want, and by making this mod I doubt that It would keep it's value...

I was interested in FPV. I tried it with the summit in stock form and it's really only useful in low gear. FPV rock crawling is cool and the summit is a good platform but it doesn't rock crawl very well. So I found myself having to retrieve the truck all the time. Now that it rock crawls much much better, FPV rock crawling with it is totally fun.

[beauregard]

Very cool.. Any actual driving video from the FPV downlink?

I've done lots of Aerial FPV.. But now want to do the FPV crawling..

[raginglizzard]

thats sick looking!!!! dare to be different!

[Liighthead]

nice, only thing i would chance is put the FPV camera in the middle more. i think it would be much easyer to drive
and maby forward more? so in middle..

idk just a thought would love a FPV :/
and like on the edge of buying a summit.. but yeah carnt make up my mind atm lol