Locked UP's TRX-4

[Locked Up]

Here is what I did to change the wheelbase.

First I looked at moving the rear axle in because I thought it would be easier.
My issue there is that is moves the COG towards the rear of the truck in relation to the wheelbase. I'm never a fan of doing that.
I also wasn't sure I'd be able to reuse the same body mount holes and I hate punching more holes in a body.

So I decided to look at the front.
Benefit is that you are moving the COG forward in relation to the wheelbase, which would make for optimum climbing ability.... and as you will see, I used the same body mount holes.




I started by removing the cross brace from the front shock towers then I loosened the shock towers themselves. I reinstalled the cross brace but flipped it 180*. Then I slid everything back right up against the the servo. This causes the shock towers to move back about 1/4". So, I actually let the servo be my guide on location for the shock towers.


Next I drilled some M2.5 holes through the chassis using the shock towers as my template. For the forward holes, after I punched through the chassis I kept drilling into the servo mount. Then I switched to an 3MM bit and drilled the front again, but only through the chassis, not the servo mount. That way the servo mount will act as the nut for the screw.


For the rearward holes, I tapped them to M3 thread. You could just as easily put an M3 nut back there... I just have a tap so why not.

[Locked Up]

I first made some temporary links out of bits and pieces I have here. I usually do this so I can check cycling and make sure everything is where I want it.

Once I was satisfied with the length of everything I went ahead and grabbed the stock links for modification.

The stock links are a mild steel so they are really easy to turn down and put more thread on.
I know using the lathe is cheating ... but I couldn't help myself.


All together I removed about 10mm from the front lower links.


Here is a finished one compared to my temp link.


My trick for helping myself set the lowers up evenly.


Lowers on.


Temporary upper link and the stock link.
I believe I ended up removing about 7.25mm from that one.... I think I need to take a bit more from it though.

[Locked Up]

I also removed a bit of material from the front driveshaft. Probably a few mm from each end shaft and the center portion.

Before


After




I did find some light binding at full compression.
Part of it may be the differential cable.


That does not concern me because I've already got a prototype FI Spool to go in there and then I will ditch the cable.

Then I found the real issue.... the front driveshaft is contacting the lower portion of the trans cross member.


It's hard to see, but it is why I probably need to take a few more MM off the upper link. The pinion is pointing up a hair more than before and causing the driveshaft to kiss that piece. No big deal though.

I still need to finish my trackbar and remove the all thread anyway ... it's a work in progress.

[Locked Up]

My next tweak is to add a bit more weight to the front end of the truck.

There are a lot of products for the TRX-4 already that allow you to add weight. I've seen all sorts of brass components out there but it's just not my style. I wanted something scale, SORRCA legal and did not want to bolt on a giant weight that doesn't look like a portal... I guess that is repeating myself but...

Anyway, I'm happy to unveil these right here in this thread.
Yes a product release in this thread!



What you are looking at are our Black Steel Portal Covers and Black Steel CHubs for the TRX-4.
I hope you guys like em!

Together these weight 159g... so it's a good chunk of weight, right where you want it.

[Locked Up]

Those of you with good eyes may have also noticed the front bumper mount is not a Traxxas part.

We have been working on a few items for those of you running shorter bodies and have 2 different bumper mounts available in our Shapeways store.

Yep. Shapeways.

TRX4 Short Bumper Mount 1

[svt923]

Originally Posted by Locked Up

I've already got a prototype FI Spool

This is all I came here for.

Wake me up when the phrase "TRX4 FI spools are in stock" is uttered.


I guess the other stuff is pretty nice too.

[Inspector86]

Originally Posted by Natedog

Nice job shortening the front suspension, very nice Black Steel portal covers and C-hubs to remain SORRCA legal too! Any plans for zero offset front bumper mounts?

Natedog beat me to it, but I'm also looking for a zero vertical offset TRX4 bumper mount with the standard extension. Actually, I could see a use for a zero offset in both a standard and short extension.

I also have a question about the steel parts above. You stated that together they add 159g. Is that 159g per wheel or total for the axle?

[CODYBOY]

Originally Posted by svt923

This is all I came here for.

Wake me up when the phrase "TRX4 FI spools are in stock" is uttered.


I guess the other stuff is pretty nice too.

I ordered one from RPP an hour ago. Some different weight springs also.
Ernie

[Locked Up]

Originally Posted by Inspector86

Natedog beat me to it, but I'm also looking for a zero vertical offset TRX4 bumper mount with the standard extension. Actually, I could see a use for a zero offset in both a standard and short extension.

I also have a question about the steel parts above. You stated that together they add 159g. Is that 159g per wheel or total for the axle?

Will have the mounts available today as "First to try".
Renaming a few things in there to make it easier to understand (I hope)


159g per axle.
Once we finish up the knuckles everything together will be about 4.3oz per wheel ... which is right about how we like to run our trucks with wheel weights.

Originally Posted by CODYBOY

I ordered one from RPP an hour ago. Some different weight springs also.
Ernie

He is waiting for our FI spools ... which are not available on RPP yet because we have not finished them yet.

[CODYBOY]

Originally Posted by Locked Up

Will have the mounts available today as "First to try".
Renaming a few things in there to make it easier to understand (I hope)


159g per axle.
Once we finish up the knuckles everything together will be about 4.3oz per wheel ... which is right about how we like to run our trucks with wheel weights.




He is waiting for our FI spools ... which are not available on RPP yet because we have not finished them yet.

SORRY! my bad.
Ernie

[Inspector86]

Originally Posted by Natedog

I'll buy a zero vertical offset standard extension front bumper mount as soon as they are ready!

Very nice job on the black steel parts!

Patiently waiting on your awesome quality FI spools!

Just purchased two of the ZeroV 11.5H TRX4 bumper mounts. Thanks LURC!!!! Also, are you going to be offering the inner rear portals in steel as well?

[Locked Up]

Originally Posted by Inspector86

Just purchased two of the ZeroV 11.5H TRX4 bumper mounts. Thanks LURC!!!! Also, are you going to be offering the inner rear portals in steel as well?

Front knuckles will be first but it is a distinct possibility.
👍

[Locked Up]

Got some pictures from being out and about this weekend.

Not many and nothing spectacular.... but the truck handled very well and I'm really pleased with where it is headed.







And for those wondering about the ability of the DIY beadlocks ... wonder no more:

[ruinx]

This build is the schiznit Love what you are doing keep it up

[Locked Up]

I picked up a DX5R to run this truck and to replace my Futaba 4PKS.
I'm still working out how to get it all setup exactly to my liking but am pretty close.

Anyway, went out with some locals today. We didn't get the best weather but I got some decent stick time with a new radio, and a couple of glamour shots.





I really need to get around to removing those decals.


After the drive I have a "want" list for the truck.
Bumper feels HUGE. Must get something better for approach.
Need to add a servo winch.
Add a BEC because the steering servo is not cutting it as is.
If that doesn't make it loads better ... something big goes in.
I think I will narrow the sliders a hair.

I also seem to be hitting the low voltage cutoff on the ESC really, really quickly.
It's quite possible that I need fresh packs and the ESC is fine... it's just something I need to look at.

[Locked Up]

I almost forgot ...

Little video is up of me beating on the DIY beadlocks.
https://www.youtube.com/watch?v=-WTq...ature=youtu.be

[Stewdog]

Great pics, looks like fun! We have too deep of snow to run anything, for now.

What ESC are you running?

[eric113]

On the bec I suggest a bypass Holmes make one. The 3 mini servos don’t like voltage over 6.0v. Then you can set the bec at your voltage choice.

I have a cut down stock front bumper if you like to try that?

[Locked Up]

Originally Posted by Stewdog

Great pics, looks like fun! We have too deep of snow to run anything, for now.

What ESC are you running?

Stock TRX4

[Locked Up]

Because I can never leave things alone, I decided I wanted to convert the rook rack to a lower profile.
It is partly just the appearance, but mostly because I felt the SCX10 II rack was getting snagged on things left and right.

So I printed a couple of parts.
(These will be available on Our Shapeways store very soon).



Then I trimmed 5mm from the top of the roof rack.


Then I started with the sand paper to make sure I removed an even amount. Do a little at a time.


Final measurement I ended up with:


You will need to redrill holes in the rack, and I actually suggest doing that first so your drill bit doesn't walk around as much.

Going back together.


I also trimmed about 13mm off the front portion.

If you are doing this then maybe do 11mm first cut then remove more as needed.

The rack came to me imperfect, so it is a little tweaked, but I like the shorter look and I know it will work better in the field.


I also wanted to put some lights back on. Not sure if these will stay or something else will make it's way up there.




And a shot of the body on the chassis with some 1.55s.



If you want some TRX-4 1.55 info:
TRX4 - AO8™ Axle Flanges and Pins


Woohoo!