ED painting on Spa frames

[fastpedaller]

This is the explanation of the frame painting on Spa's website:-

All Spa Cycles branded frame and forks are ED Coated.
(ED stands for Electrophoretic Deposition. For steel frame bicycles, what this means is that the conductive steel frame and fork are placed in an liquid that has paint particles suspended in it. The bath is put under the influence of an electric field, and the paint particles are attracted to the charged frame and fork. The particles are fused to the frame and fork in a perfectly uniform thickness. The thickness of the coating can be adjusted based on the strength of the electric field.

Have the Spa frames only recently received this treatment? maybe 531Colin may know?
My Tourer frame is 5 years old, and the inside of the tubes isn't painted , although I've squirted in a wax preservative
When I first saw an earlier note about ED painting I wondered if the process was one I'd heard of years ago, being a small electric charge to the frame and the opposite to the spray gun being used, in order to minimise paint loss due to overspray? But it would seem not.

[LittleGreyCat]

Have you considered they may have put plugs in the openings to stop paint getting inside the frame?
Interested in the answer as well.

[fastpedaller]

Have you considered they may have put plugs in the openings to stop paint getting inside the frame?
Interested in the answer as well.

wouldn't it be beneficial to have the frame painted inside though?

[landsurfer]

Have you considered they may have put plugs in the openings to stop paint getting inside the frame?
Interested in the answer as well.

wouldn't it be beneficial to have the frame painted inside though?

Double the paint area .. double the cost .. is the reality ....

[LittleGreyCat]

Have you considered they may have put plugs in the openings to stop paint getting inside the frame?
Interested in the answer as well.

wouldn't it be beneficial to have the frame painted inside though?

No reason not to do it with other painting methods if there was a clear benefit.
Spray painting probably wouldn't get paint inside.
Any form of dipping would, assuming that the holes weren't plugged.

If there was a real benefit then plug the frame, pour some paint through a hole, plug that then shake the frame about a bit, then drain.

[PH]

I think it’s a new process, or for some reason has become more common. I don’t think the Spa frames have always had it.
Thorn frames also come like this, which only started a few years ago. And I’ve noticed it mentioned from a couple of others.
Shouldn’t be hard to spot if your frame has been done, just take the seat post out and shine a light down.
Whatever it is, it’s tough stuff, I’ve scraped the paint on my Thorn and it hasn’t gone through the black layer.