Aluminum A-arms

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LMAO! I know it's just going to cause hinge pin and hinge pin blocks to break. I've pulled the pillow ball out of the front lower a-arm twice so far.
 
kurtblastoff said:
Is anybody running Aluminum a-arms on there kagama 6s?
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On a 1/8th scale rig, it's rarely (if ever) a good idea to use alloy arms. They're significantly heavier and don't flex enough compared to composite nylon. When aluminium alloy flexes too much (past the elastic limit) it stays bent. Obviously bending it back to shape causes permanent damage and weakness to the part.

The unsprung weight is increased, which noticeably reduces suspension response performance.

Alloy makes excellent diff housings, hubs, hexes, shock towers, primarily because these are areas where flex is not desired and where heat build up can be dissipated without the components going soft.

The use of alloy arms make more sense on larger, heavier rigs - 1/5th scale or larger rigs can trade heavier components in exchange for greater rigidity and precision.

At any scale, lightness has a quality in of itself. 👍
 
kurtblastoff said:
LMAO! I know it's just going to cause hinge pin and hinge pin blocks to break. I've pulled the pillow ball out of the front lower a-arm twice so far.
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Just replace arm with stock one threads must be stripped if pillowball keeps pulling out. But if you really want to go metal these Kronos metal arms would fit.

I just found this on AliExpress: ￡13.87 | Metal Front and Rear Suspension Arm Set For 1/8 Team Corally Kronos RC Car Upgrades Parts Accessories
https://a.aliexpress.com/_EwwqodQ
 
What the heck you doing to that poor Kagama that its ripping out the pillow ball :ROFLMAO:.
 
:ROFLMAO: running her hard! I also ripped out the rear hinge pin. They are to short at 68mm. I see they sell 70mm. They move back and forth 3mm that's to much play.
 
What would be nice is plastic arms with pressed in precision brass bushings for the hinge pins and threaded brass inserts for the balls. That would give you everything you want from an aluminum arm without any of the drawbacks.

EDIT and maybe replace the standard 4mm upper shank bolts with precision machined shoulder bolts.
 
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Atomic Skull said:
What would be nice is plastic arms with pressed in precision brass bushings for the hinge pins and threaded brass inserts for the balls. That would give you everything you want from an aluminum arm without any of the drawbacks.

EDIT and maybe replace the standard 4mm upper shank bolts with precision machined shoulder bolts.
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My Baja has bushes for the suspension arm pivot pins. It helps reduce slop.

I think with our 1/8th rig designs, especially RTR, such fancy stuff would push the price way up.

But the front upper arms on the Kronos/Kagama have a tendency to develop slop, which also affects the caster angle. Bushes here would be super helpful.
 
kurtblastoff said:
That would dialed!
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Zero slop on my beloved Baja! 🤩

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It's a badass rig.

However, our 4S and 6S rigs would smoke it in any type of race. 🤭

Nevertheless, it is still the most challenging/ satisfying to drive. Brilliant buggy.

Fun fact: the Baja 5B was designed by Akira Kogawa, the Kyosho designer that created the legendary Ultima. The likeness is unmistakable.

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Same lines, similar cutouts in the original Baja 5B chassis.

And yes - there are some alloy arms on my Baja because the ball joints are more precise and the arms themselves are more rigid.

Overall, my Baja is lighter due to significant amounts of Carbon Fibre used. These particular wheels and tyres are very, very heavy though.
 
Horatio said:
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My Baja has bushes for the suspension arm pivot pins. It helps reduce slop.

I think with our 1/8th rig designs, especially RTR, such fancy stuff would push the price way up.

But the front upper arms on the Kronos/Kagama have a tendency to develop slop, which also affects the caster angle. Bushes here would be super helpful.
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That's why it would be an upgrade, or you could just get the bushings from Mcmaster Carr or JLC Mechatronic Parts or wherever, ream the holes and press them in yourself. I think most threaded inserts might not work with the existing arms, not enough plastic there but maybe a thinsert would be small enough. You can for sure put EZ-press thread inserts in other places like the M4 holes on the front of the steering plate for the upper hinge bolts, plenty of meat there to ream it out to 5.5mm and press in an M4 insert. The inserts are split lenghtwise and have a diamond tooth pattern on the outside, when they are installed they get compressed and when the screw is threaded in it forces the teeth into the plastic and also provides some thread interferance that somwhat mimics how a hole in plastic grabs the screw and prevents it from backing out. You also don't need special equipment to install them a vice, arbor press or a rubber hammer can work. Even a C-clamp if you get a little creative.
 
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