Can the scale stay?

[mhorowit]

4130 comes from the mill covered with a black scale.
I remove it prior to welding, but does it need to be removed prior to priming? after all, it seems to adhere quite well to the tubing - MIke

[N96337]

Re: Can the scale stay?

A black scale??? Mine's all got some corrosion preventative oil on it, but no noticeable scale. This is MIL-T-6736 seamless, normalized tubing?
At any rate, I always clean my tubing with some wax and grease remover and a scotchbrite pad just before priming (wipe off before it dries with a clean towel), because the primer needs a good clean surface to adhere to just as any other product. If it's not going to stick really well, it's going to ruin your day soon!
JH