Dlux Sportsman build

[MRCrackhead]

I've seen this mod done before, except the ball was kept in the rod end for pivoting.

Are yours solid mounted, or is there a cut down pivot ball hiding in there?

[Erik D_lux]

Yeah, its kinda hard to see but its a ball stud that comes in the TRA1942 packs. Its just like a rod ball but you dont have to deal with the nut or anything else on top of the rod end.

Kinda sorta like these but not really. I am sure you know what I am talking about.

[MRCrackhead]

Gotcha, cool idea.

[Erik D_lux]

I had to ditch the ole "Black N Tan" knuckles". The idea behind them was great but if you want to run anything more than just the knuckle themselves, they dont work so good. I think I want a bit more weight up front any how.

With the narrow version that I am running, it recesses the hub perfectly so that the hub is just proud of the knuckle face itself. Pretty perfect if I dont say so myself!

I wanted to retain the brass slugs in the holes that I made for my knuckles but now that I had little room and no real way to attach an outer ring, I had to find another way.

When I built the V2 knuckle I really wanted to fit the Tungsten weights in there as they are a pretty cool option. They just didnt work out though because of fitment issues. I ended up buying some Tungsten putty to see how that would work out. I never did compare the brass slugs to the putty due to time restraints but now that I needed something to fill the knuckle holes, it was a great time to do so.

4 brass slugs 17g



Once you put the putty in the knuckle, there was no feasible way to simply put the putty back into your hands to see how much it weighed so I just weighed the car before and after.

-1569g for the car without putty and bucket



1606g for car with putty and bucket




So the putty came out to 37g. 20g more than Brass! Pretty cool option.

As a side note, I also cut a piece of Tunsten carbide into a slug to see how they would turn out.

14g for 2pcs, should be 28g for 4.

[Erik D_lux]

I am pretty stoked about how they turned out. Nothing to fall out, full of weight and came out pretty clean looking.

[Hittman]

Good stuff Erik. I can't wait till I get my knuckles. There are some great innovations in this thread.. I can't wait to see this rig in person.

[chris.martell]

I figured out a decent way to hold the slugs in the knuckles without the need for a ring. If you take a set screw and in the outer holes on the knuckle it will pinch the slugs in the slot. You will have to cut down a set screw for the bottom of the knuckle since the bolts are already in those hole or possibly using a longer bolt in those holes might work as well but it would have to be a very precise length to do it's job holding the lower plate and the slugs.

[chris.martell]

If you think my idea will work I'd be interested in some of those Tungsten carbide slugs or even lead slugs cause the set screw might dig in and hold them better

[WHITE-TRASH]

That upper shock mount is interesting. I'd never thought about that, I have a bunch of old kyosho or traxxas screws that mounted a tie rod. They are just a ball with a phillips head in it and a 3mm stud coming out the other end. The joys of having r/c crap from the early 80's...




I like the idea of tungsten putty too. Never knew such a thing existed, off to google I go!

[Colgout]

Erik,

Is there any way to remove the Tungsten putty once you put there?

The brass and Tungsten slug are tight fit into the holes, so it hold there by itself? That's my understanding, if you want to remove them, just push them from the inner face of the knuckle? Am I right?

I am close to getting your knuckle, if I can't get the width I want for my full width AR60 build... I just brought the wraith knuckle from you too... should have wait a bit longer...

[Erik D_lux]

Originally Posted by chris.martell

I figured out a decent way to hold the slugs in the knuckles without the need for a ring.......

Yeah, that set screw idea isnt too bad. I will have to think about it.

Another thought I had was just to put a washer or something super thin under a screw where the rings are supposed to bolt on. For our application, a bolt head is approaching too tall but you could easily shave that down almost all the way, even until there is no hex hole and then when you want to remove you could just dremel a slot in the head. There may be a better fastener out there for this too.

Originally Posted by chris.martell

If you think my idea will work I'd be interested in some of those Tungsten carbide slugs or even lead slugs cause the set screw might dig in and hold them better

The Tungsten slugs were expensive and a pain to cut. I would never personally do them again. I would do putty all day long.

Originally Posted by WHITE-TRASH

That upper shock mount is interesting. I'd never thought about that, I have a bunch of old kyosho or traxxas screws that mounted a tie rod. They are just a ball with a phillips head in it and a 3mm stud coming out the other end. The joys of having r/c crap from the early 80's...




I like the idea of tungsten putty too. Never knew such a thing existed, off to google I go!

The ball studs come in packs of tra1942 which I would assume many have sitting around.

I think I may have even of bought the "expensive" putty. I think you can get Tungsten powder even cheaper and mix it with epoxy to make your own and save a couple bucks.

Originally Posted by Colgout

Erik,

Is there any way to remove the Tungsten putty once you put there?

The brass and Tungsten slug are tight fit into the holes, so it hold there by itself? That's my understanding, if you want to remove them, just push them from the inner face of the knuckle? Am I right?

I am close to getting your knuckle, if I can't get the width I want for my full width AR60 build... I just brought the wraith knuckle from you too... should have wait a bit longer...

My plan is to simply drill the putty out if I ever want to. Should be super simple.

The slugs that I provide are NOT a tight fit. They are loose so that there is never a chance of the tarnishing and getting stuck in there. The intention was to have a brass ring go over the top of them and hold the slugs in, which is not a problem except for this super narrow version where the wheel hub is far recessed into the knuckle itself.

Sucky you just bought the knuckles. Once people start adding up the price of a knuckle and then knuckle weights along with not having any of the benefits of my knuckles, it will start to make sense to everybody.

[WAM]

Just tryin' to be helpful here, not a wet blanket.

Densities:

Tungsten .681 lbs/cu-in
Brass .304
Lead .409

Tungsten Putty: .361 (density from internet source)

IE, the putty is less dense than lead, and close to half that of tungsten.
DIY from powder and epoxy is even less. Been there done that.

[Curcal]

Is that a brass version of your bully style hub? Nice!

[Erik D_lux]

Originally Posted by WAM

Just tryin' to be helpful here, not a wet blanket.

Densities:

Tungsten .681 lbs/cu-in
Brass .304
Lead .409

Tungsten Putty: .361 (density from internet source)

IE, the putty is less dense than lead, and close to half that of tungsten.
DIY from powder and epoxy is even less. Been there done that.

Interesting. Looks like I wouldnt buy that Tungsten putty. The stuff I got came in really close to pure Tungsten it looks like. Wonder how they did that?

Originally Posted by Curcal

Is that a brass version of your bully style hub? Nice!

Yeah, a bit more weight

[Erik D_lux]

Originally Posted by WAM

Just tryin' to be helpful here, not a wet blanket.

Densities:

Tungsten .681 lbs/cu-in
Brass .304
Lead .409

Tungsten Putty: .361 (density from internet source)

IE, the putty is less dense than lead, and close to half that of tungsten.
DIY from powder and epoxy is even less. Been there done that.

Shoot! I just caught the error.

I forgot to double the weight of the brass since there are 8 holes, 4 per side. So it's actually 34 g brass vs 37 g putty

I will be keeping it in since it's heavier and stays in. I will be going back to Tungsten on the berg though.

Good catch. Thanks!

[WAM]

I've been curious if I could melt a little lead and then mix a bunch of tungsten powder into it. The lead would kind of glue it together. If you could get a lot of powder in the mix it would be way denser than the putty.

[Erik D_lux]

Yeah, something like that could be way cool! I have some chunks of lead here, maybe I will try.

My first thought is that I wonder if the lead would take it. When I melt lead it builds into that bubble, like a surfactant and I wonder if you could burst that bubble or just mix?

[SkaldidDog]

Originally Posted by Erik D_lux

The Tungsten slugs were expensive and a pain to cut. I would never personally do them again. I would do putty all day long.

Yep. About $10 a linear inch for W rod and I needed a $100 diamond wet saw blade and essentially liquid nitrogen to make the cut/snap on target. HUGE pain. Never doing that again.

J

[WAM]

Fortunately the Pinewood Derby sites offer tungsten in a number of shapes and sizes. I bought a few bags of tiny cubes I'm going to use to make up some under-axle knuckle weights, Lego-style. I'm hoping to use CA to assemble the shape I want and then encapsulate the assembly in epoxy to keep it from "shedding".

[Erik D_lux]

Some small updates.... mostly just to show some small changes and easier ways to work with my products that I have found.

First, I have found that I like very little horizontal separation in the front uppers at the axle, so I have left everything the same as I am totally happy with it. In the rear, I wanted to mess around with getting a bit more as it seems that the little horizontal separation really likes to control the car (torque twist). So, the easy fix was to move the rod ball from one side to the other on one rod end and then add another. Hard to explain so here is a picture. Its a great tuning option and I think most may like it.