Projecting VM with a TDC 116 (part 1)

[P3D Gabriel Jacob <jacob@xxxxxxxxxxxxxx>]

Well here is the report on projecting VM reels with a TDC 116.
The projectOR was completed a few days ago as it was surprisingly
very easy to do, but didn't get a chance to test and write
up the details till now. All that is required to use the TDC 116
to project VM reels is some kind of carrier to accomodate the round
reels of the VM format. I didn't want to make a carrier from scratch
as to not re-invent the wheel.(and also because of limited hacker
skills ;-)) The carrier made to accomplish this was a cannibilized
VM viewer and then settled on a VM Super-Show projector for it's parts.

After getting the TDC projector and projecting regular Realist mounts
I noticed that there was a big gap between lamp and lens housing
that accomodates the carrier or slide changer. (the lamphousing actually
houses the lamps and condensers, while the lens housing holds the
projection lenses) It occured to me that the advance mechanism in the
VM viewer is rather slim and that if the viewer eyepiece and front
diffuser was sawed (and or grinded, sanded, dremeled or whatever) off,
what would be left would be the advance mechanism and portion of the
VM housing. This is what was used as a VM carrier for the TDC.

A portion of the housing still has to be sanded down slightly so that
there were no protrusions. Don't be concerned if part of the casing on
the VM housing gets sanded away because the re-enforcing bars or struts
inside the case will keep the mechanism integrity intact. Thus the final
thickness would be about 3/4 inch thick and fits into the spacing
between the lamp and lens housing. Note the viewer casing can be pried
apart before or after cutting and sanding to clean the plastic particles. 

After doing the above, the VM carrier was ready, or so I thought!
I put modified VM viewer which was now a carrier into the TDC. (If there
is any difficulty inserting it, just open the lamp housing momentarilly
to insert the VM carrier and/or adjust the focussing knob that moves the
whole lens housing outward) I put in a reel into the VM carrier and turned
on the TDC and noticed everything was upside down. Of course I didn't 
anticipate that the VM reels have to be put in upside down. But the question
was how? They are round! After going back to the drawing board I figured
out that if I wanted to keep the orientation of the carrier so that the reels
are fed from the top that the advance mechanism would have to be modified
so that it would advance to the upside down views only. This would
necessitate making new tabs on the advance mechanism and locking tabs in
the right positions. Since this would be rather tricky, in the meantime I
was anxious to see how all this would project. I took out the VM carrier
and reinserted it in upsidedown. (VM carrier with reel) Of course the
disadvantage here was that to change reels, one would have to take out the
carrier each time. Anyways after putting it in upside down I turned on the
projector and adjusted the knobs to superimpose the images and Eureka it
worked. 3D VM reel projection using the TDC 116!

It worked quite well projection wise but was a bit dissappointed that I would
have to re-adjust the tabs if I wanted to have the carrier right side up
so that reels could be inserted and taken out without taking the VM carrier
out each time. Back to the drawing board. (or to be continued in next post)

Gabriel






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