Traction................well lack of it really!

[vodka child]

having seen some amazing rigs that can seeming climb up 60+ degree surfaces with seemingly little or no drama I wondering what/where i'm going wrong.

I'm running a JP Customs HaVoc chassis with Losi shocks, Bully Axles, White Rover tyres, Mayhem Double Comp Phatty wheels (4 weights in the front no in the rear) For foams the rears have the dual compound pro line (standard foam centre with a memory foam exterior) and the front are the standard proline memory foam. Motors are Novak 55t with a 13t front pinion and 10 rear. There is plenty of wheel speed from the 11.1v lipo pack which is mounted up front - pics of the rig in my profile.

I've messed with shock angles, front spring rates, rear spring rates, change of king pin angle, wheel weighting and changing link positions and done this against a standard test to remove any variable -indoors on a MDF board at a set angle, then increasing the incline and comparing the changes back to back to see if they have made any improvement.

I've got a pretty good COG - the rig can go vertical on the rear wheels without tipping over, you can pick it up and place it on the two side wheels and it won't tip over.

I end up with wheels spining like mad and a near total lack of traction, slow approach, fast approach, front dig (fronts just spin up while the rears are stuck still) rear dig (rear wheels just spin up or the rig starts to want to tip over) coming to a stop then starting to crawl all have the same effect ,with lots of wheel speed but not much grip.

On more level (45 degrees or less) surfaces i'm good and have great axle articulation the thing crawls like a millipede!

Can anyone help the clueless newbie on where i'm going wrong, things that I can try (one change at a time etc), laying shocks further down, more upright, link placement, foams, weights etc. Having lots of head scratching moments!
Cheers
Darren

[scatterbrains]

side pics of your rig and top down pics would help dramatically, first thing i would try is put PL 2 stage in the front too. You may be to soft and "folding" the lugs instead of letting them work. IMO

[vodka child]

Thanks will give the PL 2 stage in the front as well, plus i'll post up pictures of the rig side and top down obviously with the shell removed.
Cheers
Darren

[Destroyer]

Are you trying to climb plain MDF? Most use belt sander strips stapled to a board or something else with actual traction.

[vodka child]

Here are a few picture from the rig:
view from the top down


view with the rig on it's right hand side


View from underneath with the rig laying upside down.


front side view from the left hand side of the rig


rear view from the side (again viewed from the left side of the rig)


Side view


Head on view


Rear on view


Front right side corner


Rear right side corner


This is an example of where i've had a nightmare. The rig gets to that position or even a little more vertical with no problems at all. but when i comes to actually climbing up the log, i just spin the wheels, weather i apply a little throttle or a lot - that just varies how much wheel spin i get, no grip from this point forward

[vodka child]

Originally Posted by Destroyer

Are you trying to climb plain MDF? Most use belt sander strips stapled to a board or something else with actual traction.

the MDF has a matt paint on it so the surface it quite rough to the touch (for office boy hands it's rough, for lumber jacks it'd be 2 ply loo roll smooth! ) It's not like belt sander abrasive but figured it would be close enough to a very smooth rock.

the log in the last picture i posted was from the area i go crawling at and i've used that for some bench mark testing and no changes have helped me get over the log, i have seen improvement on other logs and runs though.

Cheers
Darren

[jcboof]

First, Add all the weights in the front of your wheels. Then add about 2 or 3 oz more of tape weights in the wheel. Next.

PUT SOME GRIP TAPE ON YOUR VERT BOARD!! I'm sorry but a matte/satin finish paint on some MDF will not give any traction at all. In order to see what kind of vertical grade you can climb. you first need some unyielding traction. I can do about 71* on my vert board at home. Yes 71*
I doubt I could do better than 45-50* on your MDF vert board.

Next. Your log dilemma. Logs are slippery, especially with no bark on them. That would be a hard climb even with a perfect setup. Speed and front weight bias would help out greatly.

Your crawler setup looks fine. I would not worry about that.

[jcboof]

OK, scratch what I said earlier about your crawler setup.

WHAT THE HECK IS UP WITH THE REAR UPPER LINKS?????????

Normally you want your rear uppers higher than your fronts. But not high enough to mount to your shock arms.

I understand that you bent your upper links to provide some clearance. But you are SO adversely affecting the performance of your crawler by doing this. The links need to have a very SLIGHT bend to them. Any sharp and tall angles on upper links will throw geometry all off.

Make your upper rear links STRAIGHT, then put a slight bend in them but only if you have to.

[vodka child]

Originally Posted by jcboof

OK, scratch what I said earlier about your crawler setup.

WHAT THE HECK IS UP WITH THE REAR UPPER LINKS?????????

Normally you want your rear uppers higher than your fronts. But not high enough to mount to your shock arms.

I understand that you bent your upper links to provide some clearance. But you are SO adversely affecting the performance of your crawler by doing this. The links need to have a very SLIGHT bend to them. Any sharp and tall angles on upper links will throw geometry all off.

Make your upper rear links STRAIGHT, then put a slight bend in them but only if you have to.

Thanks for the feedback, i'll def give that a go, as you say the rear links have a significant bend in them, going from a high chassis mount bent down to the mount on the axle. The front links have the axle mount higher than the chassis mount so they angle down slightly from front to back if you're looking at the rig from the side. I'll straighten out the rear upper links and bring the top mounts down must lower in the chassis.

As a dumb question what is the reason for the front upper links to be lower than the upper links at the rear? i'm guessing something to do with geometry....

Cheers again for the help/hints and for taking the time to reply guys

[Duuuuuuuude]

jcboof pretty much nailed it. Plywood is slick, as are logs. I had to go buy a pack of 40 grit sandpaper for my incline board before I quit losing traction.

What is your weight balance? There is a somewhat good thread going about f/r balance points...just because you add weight doesn't mean that you're putting it in the right place.

[whoodie]

Originally Posted by jcboof

...WHAT THE HECK IS UP WITH THE REAR UPPER LINKS?????????...

This. Fix those links and try again. X2 on adding grip to the board. Approach it like you have unlimited traction, that way you can see what you rig can really do.

[oldhippie]

As said, your rear upper links are messed up. I would start with the overall weight and front to rear percentages. Get it as light as ya can with 60% of the weight on the front. Then get the springs/shocks smooth to keep the tires on the rocks without hopping and make sure nothing is binding in the suspension. The whole thing is keeping the tread in contact with the rocks.

[vodka child]

Originally Posted by Duuuuuuuude

jcboof pretty much nailed it. Plywood is slick, as are logs. I had to go buy a pack of 40 grit sandpaper for my incline board before I quit losing traction.

What is your weight balance? There is a somewhat good thread going about f/r balance points...just because you add weight doesn't mean that you're putting it in the right place.

Thanks, found the thread on weight (in the newbie forum there is a thread with a ton of links on there, awesome place to trawl through and self educate) a couple of days back and tried a few things from there. The rig roughly 65-35 front to rear biased with the only thing above the wheel line being the reciever and the small mounting plate i've made for it. Everything else inc the battery is below the top line of the wheels but with a forward bias - ESC on the rear axle, Punk DIG unit behind the centre line of the rig all else is in front.

From all the feed back there is a major issue with the rear upper links (got some delrin rod from 6mm up to 12mm so will just make some new links) will try than against the standard test to make sure i have a base line against previous tests then will nip into a UK version of Home Depot and pick up some 40grit sand paper for the vert test.

Again appreciate the replies and help.
Cheers

[wheelspinn]

try some pro line flat iron tires and proline memory foams. that and weighted rims was the combo of glory for my ax10..

[vodka child]

Originally Posted by wheelspinn

try some pro line flat iron tires and proline memory foams. that and weighted rims was the combo of glory for my ax10...Check the angle of the first couple climbs..<object width="960" height="745"><param name="movie" value="http://www.youtube.com/v/BE235Xv0C5I&hl=en_US&fs=1&color1=0x006699&color2=0 x54abd6&hd=1"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/BE235Xv0C5I&hl=en_US&fs=1&color1=0x006699&color2=0 x54abd6&hd=1" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="960" height="745"></embed></object>

Thanks man. The fronts are weighted (total weight 418g) and i've got PL oversized memory foam in the fronts and the dual compound PL foam in the rears. The HB white Rovers i've found to be the best of the tyres i've used so far (X-Locks, Comp Claws, Rock Stompers etc)

Be good to see the video, but the link above is pretty had to figure out, any chance you can just post the youtube URL straight from the youtube page?

[wheelspinn]

tried to embed it....strange.. http://www.youtube.com/watch?v=BE235Xv0C5I thats one.... http://www.youtube.com/watch?v=R2OUBmTomvI heres another but it dosnt show much climbing

[vodka child]

Here is the direct link to the first video, changed up the URL and figured it out

http://www.youtube.com/v/BE235Xv0C5I&hl=

Nice rig and some great climbing in there

[vodka child]

Quickest win was to put down some 40 grit sand paper on the vert board. Quick test before with a gauge showed 41 degrees as the most I could get, put down the 40 grit and went up to 51 degrees as a repeatable run, before a lot of wheel spin just broke traction.

The delrin rod I needed to make the links has arrived today so will make the changes to the rear upper links and then test again, record the results and then make the switch in front foams to the PL dual compound foams and try again. Thanks for the tips and help, already making progress