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OS builds an Ascender

OSRC

I wanna be Dave
Joined
Sep 1, 2011
Messages
4,420
Location
Douglassville, PA
Got mine on Thursday, it's been sitting in the box teasing for a few days. Couldn't help myself and tore into it last night after wrestling the kids into bed. :)

The build has already been covered, so didn't bother with step by step pics. Just took a few here and there when something interesting caught my eye. So far, the build has gone very smooth, and fit and finish is excellent.

Transmission is pretty basic - had to resist the urge to tear up my twin hammers and bring over the 2 speed.
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Love the axles. Lots of good ideas going on here. These little 2mm nuts that hold the diff cover on were a mother to get in with my fat fingers. Eventually, I put them on my 1.5mm driver and used that to guide them in from the back. Heaven help you if you drop one, spent 20 minutes looking for one that escaped off my workbench.
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The CVD's are nice and smooth, didn't have any of the binding issues that Harley found. I'm sure there's an easy way to get the spring retainers on, and I think it's a smoother overall design than using a setscrew (which can bind up as things wear) but I had a heck of a time getting them on. Patience ruled the day...
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Lots of nice little touches like the spacer between the bearings.
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New take on hex hub pins. Very much like this idea.
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Complete front axle. Will be doing Rich's narrowing mod later, but left them stock for now.
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Driveline done, and it was a good stopping point...bedtime.
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The CVD's are nice and smooth, didn't have any of the binding issues that Harley found. I'm sure there's an easy way to get the spring retainers on, and I think it's a smoother overall design than using a setscrew (which can bind up as things wear) but I had a heck of a time getting them on. Patience ruled the day...
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The binding was with the driveshaft not the axle shafts.
 
^^ Indeed - the front. All the CVD joints on the driveshaft and axles are the same design, all of mine were smooth. Sorry that was not clear.

Making some progress...

I like that the parts interlock - the shock towers for example key into the servo mounts and reinforce with the brace up top. Makes for a very strong and stiff chassis.
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Wire guides are all over. Nice touch
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I did have an issue with the trans mount - Wouldn't sit inside the chassis rails on one side. Had to sand it quite a bit to get it in there.

Also, Had a heck of a time with these (and had to drill out 1 side as Rich from Vaterra had mentioned - issue is fixed on newer kits). Lowers link are held in place with a single shaft, which is held in place with a set-screw. I found that using a 3mm driver to line everything up worked great, and then slid in the shaft and pushed out the driver (if that makes sense)
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When built as stock, found the front has some negative caster. Can be easily fixed by drilling some new holes. I'll adjust it when I narrow the axles.
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As nice as the K5 body is, I'm a Ford guy and had a Bronco body ready and waiting. Figured this would give me a chance to mess with the adjustable chassis and what not. Worked out pretty well! I shortened the chassis by 2 notches to accommodate the body, and then shortened the rear links by 12mm to dial in the wheelbase. Very easy to do.
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Finally starting to look like something here!
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Is this WB4 link length on WB3 chassis length? or WB3 links on WB2 chassis with the skid slid back?
 
Chassis is at 290 (WB2) to line up the bumpers, and links are at 302(WB3) to center up the wheel wells (just removed 1 of the 12mm spacers from each link out back)
 
Ready for the rocks...

Finished chassis...starting out with a 45t motor, might be a bit slow for the trails.
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Hacked up my bronco CGR body and re-used the interior
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Color came out a little darker than I'd like, but oh well. Sitting on Gmade wheels and tires, fit the wheelwells perfectly and the offset was pretty good too. Not sure on the color yet though, might look for something a little more shiny. I had to trim the bumpers on each side, and the sliders were too wide so I left them off for now. I'll fab something up later. Back looks a bit hack, will tuck the bumper in a bit later.
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Good tuck at full flex - not quite stuffed in there, but close. didn't narrow anything yet.
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Not bad for a 10 minute interior
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Finally got it dirty!! Was way off with the stock gearing/45t motor/small tires, so I was not able to give it the full trail run, but took it out for a bit after and gave it a quick shakedown. Rumming a 645MG and a 45t motor on 2S.

First impression was how smooth it was. After running my "battle hardened" rigs all day, it was eerie how quiet and smooth this rolled down the trail.

Has a ton of flex, but is still pretty stable. Only rolled it once when I was trying something dumb. I thought the shock oil was going to be too heavy, but it kept things under control very well. No bouncing and very predictable.
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I noticed some torque twist for sure. I was hoping the smaller body would help, but it still jacked up the right side. Got quite a few ideas on haw to tame it down.
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Only thing I can say for sure I did not like was the caster angle. Not sure if I spoofed it up shortening the links (though the pinion angle is dead on) or what, but it's enough to hinder turning imo. Tires were all but folding over. Easy fix though given the axle design.
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Random notes:
Speaking of steering, this truck has gobs of it, and the CMS/panhard setup worked great - had no issues at all transferring the servo's torque.
Really noticed the smaller pumpkins. Running smaller tires I expected to get hung up a lot more, but I sailed over some knarly roots without a hitch.
This truck is heavier than a lot of my scalers, and that helped it to really dig in.

Overall, first impressions were excellent! Very happy with this truck!
Now time to do some mods.... :):)
 
Looking great! Can't wait to see what you come up with next. How was the wheel speed with the 45t on 2s?
 
Nice build, Bronco looks awesome. Great idea for an "instant" interior. I had the same issue with the rt side trans mount. The small diff cover nuts were a challenge, I just started a screw in the nylon end to hold it in place until I started the through cover screws.
 
Just as a follow up, finally got the caster issue fixed. CA'd the hubs in the right spot, then drilled out and used a setscrew top and bottom. Not going anywhere, and the truck turns 100% better!

Before:
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After (truck is facing the other way)
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Have you tried another motor yet? I was thinking of the 45 turn. I have the 2 peed option so that should help right? I will have essentially the same set up as you just shorter chassis.
 
Currently running the 45t and a 2 speed trans. Seems to work well together, though I might bump up to a 27t and gear down a bit
 
I almost traded this truck away (Sorry 1.55 yota, gave me too much time to reconsider)....haven't even touched it since I put the 2 speed in, and I've driven it for all of maybe 20 minutes - 10 of which was in the basement trying out different motors. I figured it was worth at least 1 trail run before I part ways with it.

Before heading out, I made a bunch of changes
  • Cut up the shock pistons for a much more active suspension - a little too much up front - oops.
  • Limited downtravel on the shocks by 10mm (!) Was way to flexy for me.
  • Relocated rear shocks to help with the torque twist
  • Mounted the battery on a frame rails
  • Added some cheapo rock sliders
  • Put the steering links back to stock - the high steer set-up I concocted was banging off the servo horn.

Took it out and put nearly 2 4000mah packs though, it did real good. REAL good. The difference from the first time I drove it was night and day. Tires broke in and finally started giving some grip. Torque twist was seriously reduced as well, and more gains to be had there I'm sure with a little link tuning. Even though this is a first gen truck I had no broken parts either. I had a backup rig on my back just in case (Twin Hammers, it was a Vaterra day), but the truck had no issues at all. A few pics from the run:

Really want to do something with the bumpers if I keep it. Front is ok, rear just looks off.
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Crawled right up there, no problem - steeper than it looks. If I got traction, I usually got up there.
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Stalking the Axials.....lol. Love this pic
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This is about it for flex now, might even limit it a bit more..not sure. Entire suspension is worlds better now that I trimmed the pistons.
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Gmade tires were OK. Did good on the rocks, but really struggled in the dirt. Better than I thought they would do though. Perfect size for this body and chassis set-up, I hate to go larger. Really noticed the smaller pumpkins too - very rarely got hung up, even with the smaller tires.
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Still not sure what to do with the rig, but feeling much better about it after this weekend. :) I am debating narrowing the axles and going to a much shorter WB...Tamiya sized.
 
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