ULTRAPHOTS: STRIPPING & CLEANING



I find it most convenient to work with the instrument on the floor, on a carpeted surface, and proceed as follows (I hope to add some photographs to this section in the future):
  • Remove the lamphouse(s)
  • Remove 2 X 3 large screws from the base of the sides of casing. (Use a screwdriver with a wide enough blade not to chew the slots!)
  • Remove the lamphouse dovetail flanges from each side (2 X 6 screws) Don't lose 2 X 3 nylon spacers which can be loose!
  • Remove the illumination changing lever from the RHS: (3 black screws + 1 large central chromed bolt). Don't lose the locking washer when withdrawing the chrome bolt!
  • Remove the mirror-actuating drum (upper RHS) - 4 black bolts around its base.
  • Remove the casing by pulling it backwards and slightly upwards. It is often sealed under the rear of the photohead seating with a black bitumen-like compound. If stuck, use a short length of hardwood and a small hammer, tapping the casing at the rear edges of the lamp- and mirror-actuating drum apertures.
  • (Removal of the casing gives access to the main casting, mirrors, etc)
  • On RHS, near the rear of the casting, there is a large rectangular plate. Remove 6 large (usually tight) screws and withdraw. (The one at top left corner may pose a difficulty, since the cut-out in the frame is barely large enough to allow a really adequate screwdriver to be presented in line with the screw.) There are also 2 stout locating pins! Carefully withdraw the unit.
  • (Reveals the 2-sided, surface-aluminised mirror used to direct the light from the lamps for epi- or transillumination. Seen below is the upper surface of the auxiliary lens used to changeover from 'micro' to 'Luminar' illumination.)
  • Setting the lever to 'Micro' swings the auxiliary lens out of the way to give (tight) access to the mirror underneath, for cleaning.
  • Slide the mirror carriage forward to give full access to the upper surface of the base casting etc. Remove dust, dead invertebrates, etc., from interior (damp cloth on painted surface, vacuum cleaner then masking tape on matt black finish).
  • Clean all mirror surfaces:- Blow loose dust off but, if using a compressed gas can, do not direct the spray downwards, or from too close to the surface, for fear of chilling it. (Fit a flexible tube to the nozzle). Use fairly wet Kleenex and no manual pressure to wipe the mirrors. If a greasy film persists, it may be necessary to resort to the use of a commercial window/mirror cleaning spray. Dry with lens tissue. Use breath and more lens tissue to remove any smears. When wiping the 2 main mirrors, wear a cotton glove, otherwise sweat, etc, from the back of the hand may be transferred to the surface of the upper mirror while you are polishing the lower one. Clean the upper surface of the 'Micro - Luminar' lens in a similar fashion.
  • Reassemble in reverse order. The front edge of the casing , which fits under a lip at the rear of the cast iron 'limb', may need to be greased in order to refit it, and the wood block and hammer now used to tap the front edges of the apertures forward. Note, in particular, that the elongated corners at the bottom of the front of the casing have to slide under this lip both from behind and beneath, and are easy to buckle! (If the Ultraphot is on the floor, and there is no-one around, the quickest way of re-fitting the casing is to 'mount' the instrument from behind and, pressing its front edge under the lip, to 'nudge' it forward with short pelvic thrusts. Failure to lock the door during this operation may lead to some embarrassment.)
  • Replace the mirror-actuating drum: in order to retain the full movement of the mirror carriage, push it back to its rear stop and then rotate the drum clockwise as far as it will go, before engaging its pinion and screwing the drum to the casing.
  • During re-assembly, the only real difficulty is likely to be encountered when refitting the lever which controls the direction of the light from the lamps. For transmitted light from the RH lamp, it must 'click' into position when pointing to '4 ' and to '2' for epi-illumination. Curiously, the boss of the lever only connects with the spindle of the mechanism via a star locking washer, so the central bolt must be fully tightened - once the lever is correctly positioned - or it will slip.
  • Carefully roll the instrument onto its LHS, using a thick cushion to support the side of the casing.
  • Remove 4 rubber feet and central large headed screw. (U/p ll). The base plate cannot be withdrawn without undoing the 2 screws which attach the Luminar/micro setting lever. Beware 2 locating pins which may be loose, and slide the lever out. In the case of the U/p lll, the feet are attached to the frame itself, and the base is secured by screws at the front and rear, as well as the large central one. (When replacing this base plate, make sure that all these screws are in position before attempting to tighten any!).
  • Removal of base plate reveals the illuminated field diaphragm and two surface-aluminised mirrors which direct the light first horizontally forwards, and then upwards, during transillumination. Since they face upwards they collect a film of dust. The front mirror is particularly difficult to clean because of the condensing lens which is next to it, but my advice would be to resist any temptation to remove it!
  • The diaphragm may need oiling, if its action is stiff. In addition, the base of the U/p lll contains a set of filters, and these will need to be removed for washing. They are easily pushed out of their mounts, together with their retaining rings, by pressure applied to the back of the filters.
Good Luck!

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