[photo-3d] Whew! Just Completely Dis-assembed and Cleaned My Project-or-View

[aknecht@xxxxxxxxxxxxx]

I wanted to give something back to the group, in return for all the 
assistance and informative dialog that I continue to receive from 
it.  I contemplated placing this entry into the Tech3D but, there is 
really nothing technical about servicing the TDC Project-or-View.  
So, if I am wrong to place it here, please excuse me and refrain from 
flaming me.

ANOTHER TREATISE ON DISASSEMBLING, CLEANING, AND RE-ADJUSTING MOST 
MECHANISMS ON THE TDC PROJECT-OR-VIEW:

After finishing, after almost 6 hours, I disassembled the POV 
completely, cleaned all surfaces and fixed an inoperative stereo 
separation mechanism . The POV performs beautifully and is very 
bright and contrasty. If I were to do it again, it would now take me 
perhaps 2-3 hours, maybe less. Harry Poster discussed doing this at 
one time, but it's been awhile since this subject has been re-
visited. I just wanted to drop some hints for anyone doing the same 
for their POV. 

1. REMOVING THE CASE HOUSING, FAN, AND BULB HOUSING:  Turn the POV 
down on its face, while pushing the screen-like panel into the 
projector position, so it won't fall on its on when turning the POV 
over.  I am including how to remove the plastic housing, which is by 
unscrewing the two thumbscrews under sides of the housing and gently 
pulling the two halves of the plastic housing apart. And I am 
including the removal of all the screws that are in two rows, on both 
sides of the underneath, including a third bottom row, plus the two 
larger screws which hold the fan in place. CAUTION: The two screws 
holding the fan, when removed will leave the fan hanging from its 
power wires, which may or may not be frayed or delicate. Just be 
prepared to grasp it as soon as you remove the bottom plate and 
gently pull it from the rubber holder where the fan shaft connects to 
the main housing.

2. REMOVING THE POLARIZING SCREENS:  These are held in place by a 
long, hozontal pin (it looks like a metal hanger wire) which can be 
pulled out  sideways by grasping the only thing on the pin that looks 
like a handle. Pull the pin straight out from the side where the 
handle thing is. If you are looking at the back of the fan/bulb unit, 
the handle thing is on the right side. When the pin is removed, you 
can lift the polarizers straight up and out. You might have to pry 
the sides of the frame out slightly to get the polarizers out. Not 
sure if this is important, but you might want to mark or place a mark 
on the front and top side of the screen prior to or when removing it 
so that it is replaced in the same orientation.

3. REMOVING THE LENS SEPARATION MECHANISM (aka the interocular 
adjustment as on a stereo viewer). To remove the lens barrels from 
bottom/front of the POV, first unscrew the tiny screw that holds the 
focussing knob. Next, remove the E-ring from the shaft. Then, screw 
in the knob's shaft until it clears front of the POV. Use a jeweler's 
screwdriver to unscrew 4 screws underneath the lens barrel housing, 2 
of which are hiding under a spring on each side. Gently wiggle out 
the barrel lens housing until it clears the POV housing/frame.  

4. MARKING THE LENSES TO AVOID RE-FOCUSING LATER: Prior to unscrewing 
the achromats from the focussing lenses, use a white pencil or crayon 
and make a straight line mark across the lens barrel to the backlite 
lens holder. I used my wife's white finger nail pencil. The note how 
far in the lens barrel is in relation to the backlight lens holder 
(The lens holders are those 2x2 square that are surrounded by the two 
springs and belts that control the stereo lens separation housing.)
Marking the position of the lens barrels will ensure that the focus 
will not need to be re-adjusted when you re-assembly the lens barrel 
housing. If you fail to do this, you will be in a world of hurt 
attempting to re-focus the lens barrels because the fan will be in 
the way and the heat of the lamps will be hot. I heard you can use a 
flashlight in a darkened room with the fan housing attached to re-
focus. In my case, it was the stereo lens separation that was frozen 
tight. 

5. ADJUSTING THE LENS SEPARATION: Regarding the lens separation 
mechanism (aka the interocular adjustment as on a stereo viewer), 
which is controlled by the top knob on front, even with fresh grease 
the square lens barrel holders were too stiff for the dual springs to 
close in the lenses. I think the reason for that is that bakelite, 
which age, is not as stable a chemical mixture as one would think. 
Bakelite, like old plastic opthalmic eyeglass frames, are in chemical 
imbalance. The correct definition is somewhat the oposite of 
homeostasis. With age, bakelite appears to expand/contract depending 
on the environment of where it is usually stored. Therefore, I had to 
file down the sides to make the square pieces slide easily across the 
steel plate in which they reside. Not having a metal or wood file 
handy, I simply walked outside and rubbed the sides of the bakelite 
squares on my cement sidewalk, while making sure I didn't grind it 
too much. Now, the stereo lens separator contraption is very smooth. 
Warning-Grinding too much will cause the squares to have too much 
play and the springs will not be able to overcome/over compensate for 
the slippage.

6. CLEANING: You will now have complete access to adjust and clean 
the barrel lens achromats, focusing mechanism, mono-lens mechanism 
which is used for viewing non-stereo slides, and of course, the lens 
separation mechanism which is used to fuse the slide images for the 
viewer and projector so that you can get a stereo effect (aka the 
interocular adjustment as on a stereo viewer). 

You might want to use canned air (used for computers) or a camel's 
hair brush or clean small paint brush to clean out the POV, but avoid 
blowing or wiping any dust or other dirt against the lenses, because 
there is a chance of scratching, although glass lenses generally are 
scratch resistant to common dust and soft debris.

While you now have access to everything, remove all the large 
magnifying lenses in front of the projection lamps and clean them 
with a liquid lens cleaner, which is available at any camera shop or 
BestBuy. Basically, it is denatured alchohol, UNLIKE the rubbing 
alchohol used for removing nail polish or for antiseptic purposes. 
Rubbing alchohol will leave a gummy residue behind, which is not 
desired. Use a clean soft cloth or lens tissue for the lenses, even 
the barrel lenses, which you all probably already know how to do. On 
each side of the fan transformer, is a bottle-cap looking piece where 
the fan shaft goes through. You will notice a small hole on each 
piece. In this little hole, there is packing material that needs to 
have a drop of oil in order to be moist. The packing material holds 
the drop of oil to lubricate the fan shaft, which in turn, keeps the 
fan quiet. I used 3in1 oil, but most any low-viscous( light, not 
heavy and thick) lubricating oil will work.

7. RE-ASSEMBLING: This should be self-explanatory. It is basically 
reversing the above steps. Try to avoid forcing anything. If it came 
apart easily, it will go back the same. Just remember to guide the 
fan's protruding shaft back into the rubber that it attached to the 
main housing. And remember my note on placing the polarizer in the 
same orientation as it was removed. Good Luck!

Flextone


 

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