Ive always heard that if you paint a driveshaft, it will throw off the balance. Ive never had the opportunity to test the theory, so Im not sure its valid. My friend said I was crazy and that a few ounces of paint wont do anything. So is it esentially an automotive version of an old wives tale?
Yes, it is. Look at it from a physics point of view: putting the same amount of paint 360 from front to rear the paint is at zero balance and only the driveshaft weights will be in play. I've never heard of paint becoming an issue, even when uneven, or for that matter, material loss through corrosion. Devon
if the paint is even that is if you had more in one section or another due to a low spot pit over spray etc in theory it could..........but your talking less then a gram i cant see it being anything noticeable. i cant see paint adding more than 2 ounces even at all. the whole idea it would harm is a stupid concept really. in fact a so called perfect balanced drive shaft will be off a few grams.
If we were talking about a shaft that sees 10K rpm and upward for the length we're discussing, coating distribution might be more important, but I think it's moot in the case of our cars. Devon
It does make sense. I guess that even if you applied more paint on one side than the other, the net difference would probably only be a 1/2 ounce or so if that.
In my 70 Riv - Painted both pieces and no issues, no vibrations, no funny noises.o No: I even drive it hard from time to time, engine sees maybe 5500 RPM...not sure exactly what the drive shaft sees?
Not too tough to figure out. Divide your rpm by trans gear ratio. For a TH400 trans with zero converter loss, at 5500 rpm in first, your driveshaft is at 2200 rpm. In second, it's at 3620 rpm. If you can get to third gear at 5500 rpm, the driveshaft is at 5500 rpm too. Devon
Jason, your all wrong my friend, it's not the black paint that causes the imbalance, it's the stripes, if you paint them wrong it causes the driveshaft to twist improperly :moonu:
You'd have to gob an awful lot of paint on the driveshaft to make it out of balance. The paint is only going to be a few thousandths of an inch thick. You could wrap it with plastic wrap- that's about how much paint you're going to add. A 12-oz rattle can is mostly propellant and solvents. I'd say that amount of unbalance is in the milligrams in this case. Paint away!
Whatever you do, don't paint it like a barber pole - the spiral and differing weights of the three pigments can cause a "whirl mode" that can cause loss of the rear tire air valve caps. :grin:
Yeah I have painted three with no issues. I bet you could even powder coat it if you want to get crazy!!!
I just had my cv joint rebuilt last year on my 64 Cat, and he painted both pieces and balanced it:TU: w/o any vibration etc. got rid of my clicking I had. Old wives tale
I have a moly driveshaft in the race car and I sprayed it eith clear engine paint years ago with no trouble.
Factory did not paint it. I wouldn't . Easiest thing to do, is have it dipped to remove the rust. Then a few minutes with 0000 Steel wool and it will look like new. You can use dry coat, ect to prevent from ever rusting again. Then apply your identification stripes. OR you can send it to Quanta, but it's expensive and will take a little time. http://www.gastanks.com/DRIVESHAFT/products/733/ DL
We do a lot of custom driveshaft work, and the shop that cuts them for us paints them whatever color we want them to be. I have NEVER had an issue with it throwing off balance, just by the physics of it, it would not make sense for it to mess it up. The driveshaft is covered completely, so the "weight" of the paint is disbursed as evenly as if it wasn't on there to begin with.
old wives' tale. a couple of years ago, i derusted my driveshaft & painted it. no problem and it looks great. i have not as yet painted the two stripes.
Only if you paint it any way other than like a barber pole :Brow: That being said, I've gotten and painted plenty of drive shaft's black and on the same note have had and seen plenty of them covered with a fair thickness of grease and road grim.
I recently had my drive shaft rebuilt with new joints and tube. It came back to me painted black. Got scratched on the way home, so I sanded and painted again. Compared to before the new tube, my vibrations were gone, totally smooth
No No No.. You have to paint it while it's installed and spinning for proper paint distribution.. Something close to 60 MPH like we used to balance tires.. Then slow it down to put the final stripes on there..
