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Diana and Clone Shutter Service

Written by Michael Barnes

Friday, 28 September 2007

First thoughts

Most Diana shutters seem to work quite well, but there can be the odd one that is "sticky", or where the apertures are either hard to select, or change of their own free will. I recently bought a Stellar clone that had a sticky shutter - well, it wasn't just sticky, it was completely out of whack! This set me to thinking about whether it would be possible to service the shutter. I knew from dropping my Diana that the lens barrel can be removed from the camera body (!), but that this does not provide access to the shutter mechanism. I decided to take a calculated risk and open it up to find out how the shutter works.

What follows will allow you to get at the workings of your shutter, but please bear in mind there is a level of calculated risk involved in doing what I did. The plastic on these cameras is ABS (Acylonitrile Butadiene Styrene) which is easy to mould, but fairly cheap and cheerful and becomes increasingly brittle with age. Since any camera from the Great Wall factory must now be in excess of 20 years old, I must stress that you follow these instructions at your own risk - neither www.toycamera.com nor the writer will accept any responsibility if you manage to destroy your camera.

Where to Start?

The first thing I always do to any new Diana is give it a good clean, particularly if I intend to take the lens barrel apart, as I don't want any external dirt getting where it is not wanted. I have found the best product for this to be one of those spray-on foaming cleansers sold for use on computer terminals. This will safely remove years of grease and grime without damaging the plastic. For parts where moisture is not a problem - the camera back and lens hood, I normally use the foam and a soft toothbrush, then follow up with a rinse under the tap. This leaves these parts looking like new. I would not suggest that you run the whole camera under the tap - you really do not want to get water in the shutter! However, a careful spray with foam and a wipe down with a damp cloth will do wonders.

If you have scratches in the plastic parts, I find an automotive cleaner/polish works very well to bring back the sparkle (I use Mer, which is made in Germany and widely available in Europe). I have even used this to remove light scratches from the plastic lenses, but this could result in even wierder focussing results (do this at your own risk, etc).

Ok, so now we have a clean camera to work on - you did remember to remove the film, didn't you?

Easy shutter service (the WD-40 method)

I suppose I should tell you that it may not be necessary to dismantle the camera to fix a sticky shutter. Conventional wisdom at Toycamera.com is that you can apply a small amount of WD-40 to the shutter to provide lubrication and ease the pivot pin. This is very good advice, providing you do not over-apply the WD-40, or it will run right through the shutter mechanism and get all over the inside of the camera, back of the lens, etc. To try this method, you need to get a small amount of WD-40 onto the shutter and allow it to work it's magic. I can suggest two ways of doing this - looking at figure 1, you need to get the lubrication between the moving shutter and the static shutter plate.

Figure 1

If you still have the little tube that came with the can, you can give the shortest possible squirt onto the shutter. The risk here is that you apply too much and it goes everywhere, ensure you blot the inside of the camera with some tissue before you put it away. To avoid over lubing, you can squirt some of the fluid into a small container (eg a 35mm film can), then use a fine screwdriver, cocktail stick, etc to deliver a couple of drops (no more) onto the shutter. Give 5 to 10 minutes or so to penetrate, then operate the shutter - if it now works, you have avoided the need to dismantle the camera!

More demanding cases

If the easy service does not do the trick, or you have another problem that you need to solve, then you may need to take things apart. OK, big breath, screw up you courage and assemble a few basic tools - Aerosol blaster (Kleene Air, or similar) slim, wide screwdriver or blunt knife, small jeweller's screwdriver, ABS glue (this needs to be one that will weld the plastic - the sort used for Airfix plastic models or uPVC drainpipes, if you can get it Methyl Ethyl Ketone (MEK) is very good as it works very quickly and leaves no mess) and, possibly cyanoacrylate glue.

I have worked on original build and clone cameras and there seems to be one significant difference (apart from quality) in the build of the lens barrel. This is around the lever that select the B or I shutter setting. On original build cameras this is in the same plane as the shutter release and aperture control. On all the clones I have seen, the B / I lever is at a slightly different position radially around the barrel, but also at a different level (usually nearer the camera body). This is the first point of entry if you want to get at the shutter. If you look at figures 2 & 3 you can see the original build layout, with the point at which you can start to split the lens barrel - figure 4 shows the clone B /I lever.

Figure 2:

Figure 3:

Figure 4

Removing the lens mount

Now - working gently, and always starting at the B / I lever position (don't ask me why, but it always seesm to be the best option - probably to do with the glue pattern), gently insert your wide, slim scredriver or a blunt knife balde and GENTLY start to prise the top part of the lens barrel away from the part nearest the camera body. Once you feel a slight movement, try one of the other lever positions in the same way, then move on to the third. This is the most tricky part of the whole operation - sometimes, particularly with clones, the whole thing will part with very little effort and no damage. Other times, mostly with original build, this will be quite a difficult thing to achieve. Just remember - be gentle and progressive with your application of leverage - don't force it, or it will break (more of which later).

Once you have the lens mount away from the barrel, you can see the shutter mechanism - figure 5 is original build, clones have their levers in different positions, but you should get the general idea.

Figure 5

Remove the aperture control plate

Remove the aperture control plate by gently pulling the pivot pin out of the plastic, just grab the lever around the pin and pull - the fit of these varies greatly, most are only a push-fit. Original build tends to be better made in this area, with a solid aluminium pivot pin, while clones have a hollow one. The plate on my clone had not even been painted matt black, but it is now - figure 6 is original, figure 7 typical clone.

Figure 6- click to enlarge

Figure 7 - click to enlarge

If your aperture plate is sloppy and won't hold a setting, there are two possible causes - one is the quality of the pivot - if the pin is loose in its plastic support you may need to use a thick cyano glue when you put it all back together; the other is the small pip at the end of the lever. If the pivot is OK, simply bend the pip up (towrds the lens) a little before reassembly - this should improve things. If you look at the back of the lens mount, see figure 8, you can see the 3 little grooves that the pip sits in to hold the selected aperture. It is unlikely that these will be completely worn away, but they could be less well defined than they were 25 years ago - this is where bending the pip toward the grooves helps.

Figure 8- click to enlarge

Lens mount - dissassembly

Staying with the back of the lens mount, you should see a rounded notch at the edge of the iris - if you intend to remove the iris to clean the inside of your lens, make sure you mark where this is - it has to be returned to its original position or the apertures will not select correctly.

If you want to get at the back of the lens for cleaning, or you need to glue your lens back in (yes, they do fall out on some cameras!), take your fine jeweller's screwdriver and carefully work it around the iris, starting at that notch, until the iris comes away from the lens mount - figure 9.

Figure 9

You can now clean the lens, or whatever. If your lens actually screws all the way out of the lens mount when you focus on close objects, you may be able to work out where to glue a small piece of plastic to prevent this (fortunately, I have not had this problem), alternattively, you could place a short length of thick rubber band in the thread and then rplace the lens, this will help to keep the lens in place.

When you have finished working on this section, remember to glue the iris back in place with two small drops of glue (the size of a pin-head), making sure the notch is in the correct position and put this aside to set.

The Shutter

Now, moving back to the main body of the camera, we can see the shutter in all its glory (!). I have found that original build tends to have a round hole in the moving shutter plate (it's partially hidden under the release lever here), but that clones have an elongated hole - look carefully at figure 11 and you will see it in the upper left quadrant of the round shutter plate. Before doing anything else, i would suggest a short, gentle blast of air from your aerosol camera blaster, or a light dust round with a soft artist's brush - this will remove any loose debris from the relatively delicate shutter.

Figure 10

Figure 11

The question of shutter speed is an interesting one - rather like Holga's, I don't think any two Dianas will have exactly the same shutter speed. The actual exposure is governed by the size of the hole in the shutter and the strength of the shutter spring. While it may be feasible to change the shutter spring, it is not a practical suggestion to start changing the size or shape of the hole in the shutter.

You will see that the shutter springs are different from original build to clone - thus there is little possibility of interchangeability of parts or, to put it another way, you probably won't be able to fix your broken Diana spring with one from a clone. It may just be possible to use the spring from a Holga on an original Diana, but I have not tried it. In extreme cases you may be reduced to making a new spring if the original has rusted through (which seems entirely possible given the age of these cameras). If you want to try this, you will need to make up a small jig using a piece of wood. You need to drive in nails of the correct diameter and in the correct positions, around which to wind a length of wire (experimentation is the order of the day - just remember to allow some pre-load in the spring).

The only wire to use is Piano Wire, which should be available from any model shop that sells real flying model airplanes, however, getting the right guage could be difficult. I have not measured the wire on my cameras, but it looks to be of the order of 0.25mm (0.012", or so), this is around 30SWG or 0010 AWG. I suppose you could also find an old piano....

The return spring is only there to make sure the shutter release returns to its starting position, it has no effect on shutter speed, BUT, if it is weak, you can just get light leaks as the lever returns. This is more of a problem on clones where the slot in the shutter is longer. I make sure that I release the shutter quickly on the up-strole to avoid any unwanted light reaching the film.

Shutter Lubrication

Looking again at figures 10 and 11, the points to lubricate with WD-40 are the shutter pivot and the release pivot - again using a fine screwdriver, apply one or two drops only to these points. Wait a short while then start operating the shutter, you should find that it eases quite quickly and becomes much more even and consistent. You may also like to apply one drop of lube to each end of the shutter spring, just to reduce friction a little.

I would suggest that you do not lube the speed selector ( the B / I lever) - mine is loose and the last thing I need is to make it easier to select B by mistake! I have yet to find a reliable way of tightening a loose selector - you can wind a length of dressmaker's cotton tightly around the post (under its head), but this did not last too long for me.
Reassembly

This is quite straightforward - first put the aperture plate in postion with its pin in the plastic pivot. This is the only area where I would even consider cyano glue - if you pivot is cracked, like mine, use a little gel cyano to keep the pin in place. Make sure you put a tiny amount of the glue in the hole, not on the pin and work the lever a few times to ensure it is free - if you get this wrong you will only have one aperture!

Next work out which way the lens mount fits on the barrel - with clones this is easy, thanks to the castellation at the B / I lever. Once you are sure you have it right put three small blobs of ABS glue inside the flange of the lense mount where it fits over the barrel - then put the parts together and hold them together until the glue bonds (about 5 minutes) you can use a weight, provinding it sits squarely on the lens mount. While it is setting, clean off any excess glue that has squeezed out of the joint - see figure 12 which shows my Diana - you can see that the lens mount did not separate completely cleanly from the barrel, but at least it gave me a datum point for reassembly. Don't be tempted to glue all the way around the barrel for two reasons - it will run everywhere and eat into the plasic with disastrous results, and, you won't be able to do this all over again in another 20 years!

Figure 12- click to enlarge

Final thoughts

Having found out how these things come apart by accidentally dropping mine, I also found out that the film spool arms can come out of position too! In figure 15 you can see where I had to glue a small piece of plastic from a cassette box to repair the lug that keeps the arm in place. If you need to do this, just make sure that you don't glue the lug to the camera body - put some tinfoil between the lug and the body until the glue is set.

Epilogue

Hopefully, all went well and you now have a clean Diana with a super-slick shutter that works like it should. If you have any problems, feel free to contact me through the Toycamera forum and I will try to help. The "before" and "after" condition of my clone can be seen in figures 13 and 14 - with a little care, you should be able to achieve similar results.