New SlipPlate Dag on a 12LP4

[Eric H]

This is my first attempt to re-dag a tube using SlipPlate and it looks excellent if I do say so myself.

Years ago I was actually able to buy a spray can of Dag and this stuff seem to pretty much look and apply exactly the same.

I probably coulda made the anode circle a little bit smaller but what the heck.

For the anode circle I laid down several strips of Masking tape on a cutting board, slightly overlapping each strip.
I drew a circle using a drinking cup, then I marked the center of the circle by eyeballing it, after that I peeled up the tape and cut out the circle with scissors, then I applied it to the CRT lining up the center marking with the anode connector.

[jeyurkon]

Looks great!

You've convinced me. That's what I'll use on the 12LP4 in the Philco that's peeling.

Did you use the SlipPlate that comes in a spray can?

John

[Eric H]

Originally Posted by jeyurkon

Looks great!

You've convinced me. That's what I'll use on the 12LP4 in the Philco that's peeling.

Did you use the SlipPlate that comes in a spray can?

John

Yes but there's more than one type.
I used Graingers# 1WVK7
The Slip Plate# is 33203G
http://www.grainger.com/Grainger/items/1WVK7


The other types are just lubricant's as far as I can tell and don't go on like Paint.

[M3-SRT8]

Got a Can of SlipPlate sitting on My Desk. Plus, I have a can of Aquadag coming in.

I've got a couple of 10BP$'s to do. I'll do one of each.

LJB

[kx250rider]

That looks totally original!!!!

One point; I didn't read in the Grainger item page that it's conductive... This is very important, as the grounded dag coating acts as the high voltage filter capacitor for the anode. If you don't have dag (conductive), you'd have to install a 500pF doorknob cap under the 1B3, as they always did in metal tube sets.

Charles

[Eric H]

Charles, someone else originally did the research on Slip Plate and I recall they did test it for conductivity.

[dreyfoos]

Here you go Eric. You're probably referring to a post I made re SlipPlate to the original AK thread entitled: "Outer coating on 10BP4 peeling." Earlier in that thread, I posted resistance measurements. BTW, your masking job looks factory to me. I do my circles with some contact paper that the 99cent store sells.


Later in the thread, I posted these capacitance figures:

My Sylvania Characteristics of Cathode Ray Tubes from 1959 shows a coating capacitance of 500 uuf min. to 2500 uuf max. for a 10BP4. It wants 750 – 3000 for a 12LP4.

I got out the old Heathkit IT-11 cap checker. I measured from the 2nd anode button to the outer coating of my freshly Slip-Plate coated neckless (thanks to UPS) 10BP4

The reading was 900 uuf.

The reading on my new RCA 12KP4 is 1100. The Sylvania reference is 500 – 2500 for the 12KP4.

How thick is the Slip-Plate coating that I sprayed on? It was enough so that I could no longer see the glass underneath.

Roger

[Eric H]

Thank you Roger, I couldn't recall who first mentioned it.

I wonder if the capacitance goes up with a thicker coating?
I put on about two heavy coats, in this case I don't think the set even needs the Dag but it looks so much nicer with it on there.