sokey70

Awesome, will you let me know how the skids turn out? If all is well I would pay you to cut me a set too. So are you gonna try the M10 setup or go with the mono-shock?

subcaptian

M10. Just need to find dampeners now. My schedule is try to get the blueprints on Autocad today, cut tomorrow. The shop teacher said the amount of aluminum I need is so small he'll just give it to me.

sokey70

That is awesome, post how it goes! I teach 6th grade and I was thinking about how you're using a local school - I figured I fwill just check with the high school's in my district and see if one of them has a mill or something. The CADs are done for the larger Polaris, any chance you can post or email the smaller ones for the Rev? That would save me a drawing

subcaptian

Well, I'm not quite using the high school, I'm a student. The shop teacher happens to like me.

sokey70

Either way you scored. LMK how it goes.

TechyJoe

Here's a few pics of the mockup suspension I started a few months ago. I re-arranged the main shock to the position you see now. It could still use a small front suspension shock.

It's not the cleanest since I created it with cardboard and popsicle sticks.

subcaptian

Reverse shocks? That might work since I can't find any shocks small enough.

sokey70

Joe, what shocks do you have on the front and what is that rear one? Or how long is the rear one?

TechyJoe

Subcaptain
One of the main reasons and benefits for the mockup was to try various shock positions. The position depicted seems to works the best for this type of suspension. I may still fool with this some until I find the best working system - so far this is it.

Sokey70
The two types of shocks are posted on page 3. They are both Duratrax. The shorter rear one is 2.8" and the fronts are 3.1".

sokey70

Techyjoe - thanks for the info. After lookign back over it and readign again, you say the 3 point pivoting system is better in the rear than the 2 point of the picture that i posted? I am trying to keep as sismple as possible yet effective and worth doing.

TechyJoe

I hate to drone on with a long blog but , what I found with the mock up 2 point system is that the suspension tends to "swing" towards the back and that tightens the track against all of the wheels which limits movement/travel and places more stress on the motor and drive train. The 3 point system tends to give more up and down as apposed to a swing. More testing on wheel tension/binding still needs to be done.

I recommend you guys mock something up as well. Just a side note: the reason I stopped working on all of this is because it was becoming very time consuming and quite the pain in the ass and I wanted to complete some work on my other existing snowmobiles and vehicles (I have a surprise - snow secret weapon in the works as well).

In all, I'm NOT totally convinced that building a custom suspension will buy you any more then using the existing one I show where I replace the tension spring (shock) with an oil filled dampener. This is because this model is very small and movement is limited by space.

Another thing you will find is that snow tends to collect/clog inside the suspension which also starts to bind things up - this happens on all suspension, including real sleds. The enclosed-ness of the stock suspension tends to reduce this unwanted collection of packed snow.

But, I don't want to stop you guys from continuing your work because this is valuable research and I'm very interested in this. I will also continue to work on this as time permits.

subcaptian

Well, if you want to know for sure, look at jazzka's arctic cat. He put better suspension on, and it works great.

TechyJoe

Some pics of my latest revision which includes:

1) New oil filled front shocks
2) New custom light weight foam rider
3) New rear anti tip-over bars
4) New Integy clip on brushless motor fan
5) New more powerful Traxxas Velineon water proof ESC

TechyJoe

Some comparison between 1/6th and 1/8th scale

Apples and oranges when it comes to suspension and track. It should become obvious that the 1/6th (larger snowmobile) and its suspension will handle the snow way better then the 1/8th.

sokey70

Any updates on your sleds? I decided to go with a rear suspension like Hurricanefibers [link]http://s229.photobucket.com/albums/ee186/hurricane-fibers/bigred/[/link] and this one on Youtube [link]http://www.youtube.com/watch?v=GbL52yINdgs&feature=BFa&list=PLA9A520391D1FDE35&lf=mh_lolz[/link] at about 1:30. I have the hweels being cut/machined right now and hope to have them soon. I just drove this thing for the first time (never had teh desire because I knew it would be pitiful) and it was horrible, the track slipped so bad. My main concern with rear suspension is to get it tighter and more grip on teh drive wheel. I also purchased some extra tracks since they are in stock from Interactive Toy [link]http://www.interactivetoy.com/parts/index.php?cPath=16_23&osCsid=8d3091652bebde24e4d2f588e4d18abe[/link]. Anyway, I will start a new thread for mine when I get the wheels and stuff. Thought I would post a pic of my 3 sleds I am working on, Polaris Fusion, Ski Doo MXZ, Rev XP - the size difference is huge between all three!

Post any updates guys!

TechyJoe

Sokey70

To reduce the track slipping on the MXZ, you need to flip around the main drive wheels. You'll need to cut some of the axle off one of the drive wheels to make this work.

See the pictures below:

TechyJoe

Sokey70
Here's what I did for the Rev XP. This stopped all slipping:

This picture only shows 4 metal tabs on the main drive wheel but I added all eight tabs to make it work really good.

us66rc

For the spring build?

Brushlessed

My Feedback: (2)

I was looking back through the pages and you were on the topic of sinking into the snow. I have two different sleds (real) and one Modded new bright one, http://www.rcgroups.com/forums/showthread.php?t=1411010 and to make it dig less, making the lugs smaller will not help. IT will reeduce traction, obvioulsly, but bigger lugs help you "get out of the hole" (thats the term we use when we are snowmobileing) faster.  Smaller lugs make you sit there and spin longer and, therefore, dig a bigger hole, which is harder to get out of. I wouldn't be concerened, I'd just leave them alone. I am thinging of putting studs on the track, though. But then, If I don't want them in there, I don't have another option. I might look around on ebay to see if I can get another track so I can have a studded and non studded.
If you can get the tunnel lower to the ground it will be more stable.
Alex

subcaptian

Well, after a long anticipated wait, I bring you all the finished products! One motor mount and two slides for the rear suspension, all 1/8th inch aluminum.

subcaptian

Hey guys, another update; today I'm going to try and have holes cut for the shock mounts and the bolts to hold the slides together. I'm not sure if he's gonna let me because I haven't done my safety tests for this semester yet.

sokey70

Nice, lucky you. I have my custom wheels being cut right now and then it's on to rear suspension! Techyjoe - do you think that a 380 would be too small for this sled? Is that the actual size of the stock can or more like 480? I don't have a 380 to compare and I would prefer a brushless 380 for size it you think it will have enough beef to power it.

subcaptian

Be like me; use a 540! The power to weight ratio still wont be high enough...

TechyJoe

Yes, 380 is too small. I used a 480 brushless (26mm) 400watt 2300kv motor (If I did this over I'd try to get a 3000kv motor).

The 540 will definitely be better and give you way more power and speed. It will also require you to build a custom drive train and motor mount. If you go this route, I'd go with a 3000-3300kv brushless motor.

subcaptian

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