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Old 12-27-2020, 01:28 AM   #21
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Default Project PrerunnerR

Unfortunately none of your pictures are working.

I put together a custom cage and I hot glued it to make sure it fit and was all squared up then popped the joints off one at a time and used E6000/Shoe Goo. I don’t think CA glue will work. Obviously screws are your best bet, but Shoe Goo/E6000 works great also. I know it’s different, but I tried using multiple different epoxies including a few from JB Weld on a lexan body and none of them worked.


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Last edited by ScaleLifeNewbie; 12-27-2020 at 01:35 AM.
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Old 12-27-2020, 02:22 AM   #22
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I’ll just post the pics here I guess


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Old 12-27-2020, 02:23 AM   #23
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I’m not going to be touching lexan , so JB weLd might work, but I’ll do some research first
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Old 12-27-2020, 07:18 PM   #24
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Well i just accidentally put a drill bit through the side of my finger, so I'm probably going to take some time off from this project.
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Old 12-27-2020, 07:46 PM   #25
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Default Project PrerunnerR

Ouch! Sorry to hear that, hopefully it wasn’t too bad.

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Old 12-27-2020, 09:40 PM   #26
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Ouch! Sorry to hear that, hopefully it wasn’t too bad.

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It was mildly bad, went through the side of the tip of my index finger. Thankfully it missed the bone

Despite my injury, I'm still finding myself drawn to this project. I'm gonna take a break from the fabrication and focus more on performance.

SCX10ii shocks are notoriously bad and leaky, but I'll be stuck with them for a month or two before I get the Traxxas Long arm shocks. Unfortunately, bypass shocks don exist in the RC world, so I've improvised. The seals on the cap of the SCX shocks seem fine, and shouldn't leak, so I've mounted my shocks in reverse.

I was going to go oil-less, but it just bounces too much, 20wt makes them too stiff. But due to the pistons being on the top of the shock (they've mounted upside-down), if my shocks are half full, the first 1/2 would act as oil-less, and the second half would be affected by the oil, this kinda makes it a makeshift bypass shock of sorts. The shocks are around 3/4 filled with 60wt and a little bit of 7k diff oil mixed in, so the shocks can still move quickly when riding small whoops while having enough dampening for the bigger jumps.
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Old 12-28-2020, 04:28 PM   #27
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, bypass shocks don exist in the RC world, so I've improvised.
There's a few guys 3d printing sleeves that slide over a standard coilover shock body to add external bypass tubes (non functioning of course) you'll see a lot of them for the Traxxas UDR. I bought a set of them on 100mm shocks from the classifieds here on RCC.

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Old 01-12-2021, 09:18 PM   #28
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I’ve done some more work on the cage, finally got the wheelbase figured out, ended up having to readjust the rear links because the trailing arms didn’t work. Are use some clear plastic to mount truly arms which look strange, but I’ll replace them with something more l permanent

For the cage assembly I decided to use screws because JB Weld didn’t hold very well there are still some glue pieces but most of it is screwed together with M2 and m3

I just ordered the Element IFS kit and a cheap Amazon sway bar, but put some wheels on it and the torque twist was way too much, which probably has a lot to do with the oilers shocks, but they won’t hold oil anyways.

I’ll get better shocks soon, but IFS and body first
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Old 01-13-2021, 07:52 AM   #29
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Right on, senor!!! How rigid is the chassis? Sucks to drill your finger, as it does cutting them using the cordless Portaband to cut steel rod or tube. Great progress. Figure out how to get some Yeti rear length shocks on the back for your bypasses, 1:1 are about 4 feet long, 4" diameter. Shapeways had the 3 tube bypass sleeves for Bomber shocks for what its worth. You are talking UDR shocks, 5-3/8 long if I recall correctly, perhaps a little long for the scale of your build??? Keep up the good work,
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Old 01-13-2021, 11:03 AM   #30
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Right on, senor!!! How rigid is the chassis? Sucks to drill your finger, as it does cutting them using the cordless Portaband to cut steel rod or tube. Great progress. Figure out how to get some Yeti rear length shocks on the back for your bypasses, 1:1 are about 4 feet long, 4" diameter. Shapeways had the 3 tube bypass sleeves for Bomber shocks for what its worth. You are talking UDR shocks, 5-3/8 long if I recall correctly, perhaps a little long for the scale of your build??? Keep up the good work,
It's actually stronger than I thought, I can lift the entire thing with any one section of tubing.

My original plan was to get 110mm TRX4 extended shocks on all 4 corners, but with the element IFS, I may or may not be able to fit the longer shocks in on the front.

The problem with the shocks is that the Proline cage takes up a lot of the possible shock mounting positions, which really sucks. I don't want to cut it, but I might have to. The yeti shocks sound reaaally nice, but I'll have to find a way to mount it, and not have it be completely overpriced.

I found a full set of UDR shocks (the entire set, including the ones without springs) for 60 dollars, not sure if I should get those. They'll be really nice but the springs are probably way to hard.
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Old 01-14-2021, 07:38 AM   #31
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UDR shocks are waaaay to big for your rig, with springs for a 13 lb truck. I saw your Powerstroke thread, and would add that shock placement can change the spring rate. ideally, when fully compressed, the shock wants to be 90* to the trailing arm, making the linear spring progressive. The more "off 90" the shock is, a stiffer spring is required to do get the same spring rate. Harder to tune the shocks than the 90* program, especially in the 1:1 world. I'm not sure if you are worried about wheel travel, but scaling your pic with the rear arms, you appear to be about 1.8:1, so measure the shock stroke and multiply 1.8 and that is what you get. 36" is the standard in the real world, so get somewhere around 3-1/2" and you're golden.
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Old 01-14-2021, 11:33 AM   #32
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Originally Posted by MAC FAB View Post
and would add that shock placement can change the spring rate..
No..thats impossible ...the springrate is always the same
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Old 01-14-2021, 11:50 AM   #33
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I think I'll go with yeti shocks for the rear. I'm putting my battery under the cage at the back, and with the added weight of 2 spare tires it should balance out.
I'll be mounting them at around 70*, I don't need perfect shock tuning or wheel travel, but I'd like it to work well

I'm not very good with suspension geometry, what do you mean by 1.8:1?

The Powerstoke XT has a extended length of 128mm and a fully compressed length of 86.7mm, which means around 41mm of travel which is around 1.6 inches of travel.

By 3-3.5 inches, do you mean overall shock length?
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Old 01-14-2021, 12:08 PM   #34
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No..thats impossible ...the springrate is always the same

Based on the rest of his comments I think he meant shock placement (angle) changes spring rate requirements. Not actual spring rate.

Keep reading to: "The more "off 90" the shock is, a stiffer spring is required to do get the same spring rate."
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Old 01-14-2021, 12:11 PM   #35
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Based on the rest of his comments I think he meant shock placement (angle) changes spring rate requirements. Not actual spring rate.

Keep reading to: "The more "off 90" the shock is, a stiffer spring is required to do get the same spring rate."
Yep, the more horizontal the shock is, the softer it is.
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Old 01-14-2021, 01:28 PM   #36
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Thanks everyone for spring clarification. Yes, the springrate is what it is, doesn't change unless it is a progressive spring-who uses those, anyhow on a go fast rig? I magnified your pic this time to see the center of the rear axle and measure to the center of the chassis rod end, new, less impressive numbers. Here is the math: divide the overall (axle to chassis rod end) length measured by the chassis rod end to shock mount location and you get a leverage ratio, which is actually 1.5:1. So, magnified for easy measurements, I get 6" overall divided by the 4" to the shock measurement from the chassis rod end. Multiply the number you just got (1.5) by the shock stroke value (41mm) and you get wheel travel. 2-9/16" is what I see now, where the shock is sitting. Move it forward to get more travel, probably requiring a stiffer spring as well because of the increased leverage. Next hole closer gets you 2-3/4", and the closest is half way, doubling the shock stroke to 82mm, 3-1/4". A stiffer spring is required to keep the same ride as the starting location now. As for the 3-1/2" number, that is scaling 1:1 stuff, 36" of wheel travel at 1/10 scale. Being this is a 1.9 rig, I think hitting close to 3" of usable wheel travel hits the numbers. What does the front cycle? Finally, you will need to pick either scale OR performance, you don't get the best of both in a smaller rig. You can either look the part or drive the part. 60/40 weight bias is perfect, it will jump flat. Finally, what kind of speed are you looking to see with this truck?
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Old 01-14-2021, 02:05 PM   #37
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Yep, the more horizontal the shock is, the softer it is.

No. The shock isn't softer. The greater the spring angle the stiffer the spring has to be to support the same weight.



Semantics, yes...but not the same.
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Old 01-14-2021, 02:09 PM   #38
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No. The shock isn't softer. The greater the spring angle the stiffer the spring has to be to support the same weight.



Semantics, yes...but not the same.
"Softer"

Look at my TRX4 for example, after I relocated the rear shocks, the whole rear end was "softer" and allowed for more flex. We are saying the same exact thing, just a different way
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Old 01-14-2021, 02:18 PM   #39
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"Softer"

Look at my TRX4 for example, after I relocated the rear shocks, the whole rear end was "softer" and allowed for more flex. We are saying the same exact thing, just a different way
Not going to highjack this thread, but no we aren't. Read this:


https://www.onallcylinders.com/2017/...unted-springs/

Edit - may help if I say I am talking about cause, not effect. I'm aware angling a shock makes the truck feel 'softer', nobody is debating that. The conversation started with what causes that, not what happens when you do it.

Last edited by Phildirt; 01-14-2021 at 02:25 PM.
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Old 01-14-2021, 03:11 PM   #40
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Originally Posted by MAC FAB View Post
Thanks everyone for spring clarification. Yes, the springrate is what it is, doesn't change unless it is a progressive spring-who uses those, anyhow on a go fast rig? I magnified your pic this time to see the center of the rear axle and measure to the center of the chassis rod end, new, less impressive numbers. Here is the math: divide the overall (axle to chassis rod end) length measured by the chassis rod end to shock mount location and you get a leverage ratio, which is actually 1.5:1. So, magnified for easy measurements, I get 6" overall divided by the 4" to the shock measurement from the chassis rod end. Multiply the number you just got (1.5) by the shock stroke value (41mm) and you get wheel travel. 2-9/16" is what I see now, where the shock is sitting. Move it forward to get more travel, probably requiring a stiffer spring as well because of the increased leverage. Next hole closer gets you 2-3/4", and the closest is half way, doubling the shock stroke to 82mm, 3-1/4". A stiffer spring is required to keep the same ride as the starting location now. As for the 3-1/2" number, that is scaling 1:1 stuff, 36" of wheel travel at 1/10 scale. Being this is a 1.9 rig, I think hitting close to 3" of usable wheel travel hits the numbers. What does the front cycle? Finally, you will need to pick either scale OR performance, you don't get the best of both in a smaller rig. You can either look the part or drive the part. 60/40 weight bias is perfect, it will jump flat. Finally, what kind of speed are you looking to see with this truck?

Ah thanks, I got it.


I'm going to put a TRX4 transmission in later, not a priority right now, but in the near future. I've got a axe system in there right now.
I'm going for 20mph, 25mph at most (locked diffs and speed do not mix)
But most of the running's probably going to be at 15 or so mph.

I'm thinking 10wt oil for the rear, maybe 15, and ill see how the front handles with no weight oil (although I feel like heavier oil up front would be better?)

I've also ordered a cheap amazon sway bar that's STIFF, which is what I need.
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