CT 100 Plastic Yoke Cover Problem

[peverett]

Ohydrofarted has a very good article on his website. I have been making somewhat crude yoke covers using the same styrene plastic(They may be cride, but they do work). As I do not have access to a lathe(nor room to put one), I have been using hole cutters. This works, but the sizes you can get are limited. It is also harder to make perfect circles with the drill hanging, etc.

A couple of things-my yoke covers are for B&W sets and have centering rings. These have to be accounted for in making the portion of the yoke cover that is clamped to the CRT to hold the yoke straight. Luckily, in two of the cases, (an Admiral and RCA), spring clamps for holding these on the cover were still in the set. The issue is making sure the centering rings can still be adjusted on your new cover.

One of the yoke covers I re-built was made of two types of plastic, the celluloid that falls apart and a center section made of a later plastic that has held up fine for 50 years(the TV is an 1963 RCA). This made the centering ring issue easier as the rings were mounted on the good plastic.

[tubesrule]

Pete,
If the pristine cover is available for reproduction, I could ask Ed (the guy who I had reproduce the VT71 and TRK12 masks and makes all the knobs and stuff) to reproduce them.

Any idea how many he would need to make and at what price? I know he is extremely busy but I'm sure he wouldn't mind adding more stuff to the list

Darryl

[Pete Deksnis]

Originally Posted by tubesrule

Pete,
If the pristine cover is available for reproduction, I could ask Ed (the guy who I had reproduce the VT71 and TRK12 masks and makes all the knobs and stuff) to reproduce them.

Any idea how many he would need to make and at what price? I know he is extremely busy but I'm sure he wouldn't mind adding more stuff to the list

Darryl

Darryl,

Sounds like a great idea. Based on known CT-100 sets of 164 minus 1 (the known pristine set), the Merrill customer base is 163. Add the remaining about 64 15GP22-based sets on the ETF 'Surviving Early Color Set Database' for a total customer base of 227. If we assume about 2 percent participation, about five clone covers might sell initially. Would a run of say 10 make a viable project?

Pete

[Steve D.]

I would be interested. I forget how the cover is attached to the yoke. And my poor back prevents me from moving my CT-100 to look. Can the old cover simply be removed from the yoke and a new repo be attached? I assume the repo cover would have a longer life than the original RCA cover. Of course the set would be unplugged during this procedure.

-Steve D.

[tubesrule]

I sent the link for this thread to Ed so hopefully he will give us his opinion after reading through it.

Darryl

[blacksmith]

Hi folks,
I could probably make the part in question if I had access to a good original. There wouldn't be any damage or changes to the original in the process of making a mold.

I would have to know the temperatures the plastic part might reach in use. Maybe someone with an infrared heat sensor could take a temp reading of the part on a set that has been working for a few hours.

[Pete Deksnis]

Originally Posted by blacksmith

Hi folks,
I could probably make the part in question if I had access to a good original. There wouldn't be any damage or changes to the original in the process of making a mold.

I would have to know the temperatures the plastic part might reach in use. Maybe someone with an infrared heat sensor could take a temp reading of the part on a set that has been working for a few hours.

Ed

Upon closer inspection, the lower half of the cover has some warping. Due I suspect to stress rather than deterioration of the plastic. Since the two notched-out areas are identical on each half of the cover, the stable half describes the whole. Perhaps that is enough for a cloning?

Can someone with a 15GP22 set make the temperature measurement if/when it becomes necessary? I do not have an IR thermometer.

Pete

[Pete Deksnis]

Originally Posted by Steve D.

I would be interested. I forget how the cover is attached to the yoke. And my poor back prevents me from moving my CT-100 to look. Can the old cover simply be removed from the yoke and a new repo be attached? I assume the repo cover would have a longer life than the original RCA cover. Of course the set would be unplugged during this procedure.

-Steve D.

Steve

It snaps in place. Two small square cutouts -- one just above my index finger-- mate with dimples on the yoke body. There are also two half-moon cutouts that match similar shapes on the yoke body to pass the yoke wiring.

Pete

[Steve D.]

Originally Posted by Pete Deksnis

Steve

It snaps in place. Two small square cutouts -- one just above my index finger-- mate with dimples on the yoke body. There are also two half-moon cutouts that match similar shapes on the yoke body to pass the yoke wiring.

Pete

Thanks Pete.

-Steve D.