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Control Arm question

AKfreak

150cc
I think I know the answer, but I wanted to ask anyways. On a servo control arm, what is the benefit of a 3mm tapped hole vs a 4/40. Is it so you can screw in a standard 3mm ball end for a control rod? I have a chance to get a good deal on a set with 4/40 holes. I know a standard bolt and swivel joint will work.

Before I make my decision, I just wanted to ask you guys, Thanks Akf
 

gyro

GSN Contributor
All bias to your deal aside, I think they are made in 4-40 and M3 because that's the two sizes used on most kits. I don't think there is advantage or disadvantage either way.

I suppose the disadvantage would be if your ball link is 4-40, and your horns are M3, as the M3 bolt won't fit through the 4-40 ball link. However, a 4-40 will fit through the hole on a M3 ball link as it's factionally smaller.
 

AKfreak

150cc
Ok, that sounds about like I understand it. I just remember reading somewhere that on the 83" MXS I need to use M3 to use the parts in the hardware package. I am still trying to verify this. I wish I could be certain. I have a drawer full of odds and end parts that didn't work.
 

hone

150cc
Ok, that sounds about like I understand it. I just remember reading somewhere that on the 83" MXS I need to use M3 to use the parts in the hardware package. I am still trying to verify this. I wish I could be certain. I have a drawer full of odds and end parts that didn't work.

The MXS does use M3 hardware(ball links, nuts, and bolts). I used spot on rc arms which are available in M3.

If you use arms tapped for 4-40 hardware you can either retap the arm or just replace the M3 bolts with 4-40 bolts and deal with the slop it creates with the M3 ball link(you change out the ball links to 4-40 also to avoid slop)
 

AKfreak

150cc
Yeah I was told a cashier will clamp it down, but I think I'll just order some ball bearing 4/40 ball ends and thread the m3 rods into them on the servo ends. I got a good deal on 7 swb arms that I'll be be able to use on my 35% project later on, foe the MSX, I will make them work. Thanks for taking time to respond to this post. AKf
 
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