What size hardware do you use for your chassis and link?

[Bmr4life]

I plan on ordering a ton of screws from McMaster, but need help deciding what size. M3 is what comes on a lot of vehicles, but since it will be mostly custom, I can always go with another size.

Do you recommend I stick with M3, or try M4, M5, 4-40, 6-32, etc?

The screws will be for making link ends, chassis braces, etc.

Thank you

[STJ7780]

I use mostly 4-40 becasue it is cheap and easy to come by. If you need something in a hurry you can usually get it at home depot or lowes where the metric stuff is a little harder to come by locally.
Steve

[vw_thing]

M3 and 4-40 will fit all standard pivot balls, shock mounts, etc.. I use 4-40, just because my metric tap set doesn't go down that far. You will find all sorts of uses for matching nuts. Non-locking is the best choice so they can be welded/brazed to your chassis. For links, you really won't be getting to the strength limits of 4-40, but you can upgrade to 6-32 if you feel like it. Not a bad idea on larger crawlers for the scale size.

My advice.. get a box of 4-40 screws and nuts. Buy them longer than you think you will need anywhere on the build and use a pair of electricians pliers to cut them. Get one good (cobalt or ti-nitride, Craftsman Professional works perfectly) 3/32 drill bit and 4-40 tap. With that setup you can put a screw in anything from soft plastic to hardened axle shafts (I've done both).

[Bmr4life]

Thanks for the replies, you answered my questions perfectly. I was going to ask if 4-40 will fit into 3mm pivot balls, but you already answered that.

Awesome.

I just learned McMasterCarr is about 40 miles from my house so I plan on doing one big drive by one of these upcoming weekends.

[crawl rookie]

3mm for the chassis and mounting the links on the chassis, 4mm in my rod ends

[mrpink]

4-40 will not fit into ALL pivot balls. Go with M3, you will thank me. Stainless steel, lock washers, lock nuts, regular washers, regular nuts. Button head is a must. A good set that will last you a lifetime should cost no more than $30, I think that is what I spent on mine from a local hardware distributor.

X2 on getting a good tap, this is where you need to spend a little money.

For link hardware, I use 8-32 all thread with revo link ends, steel brake line sleeved. BOMB PROOF to say the least. Upper links I will use 6-32 and carbon fiber sleeving, they do not take as much abuse.

M3.

p!nK