When you have seen over 100.000 cameras in person and given them a new life you become somewhat of an expert at changing light seals. Be it knowing the best tools, the best foam, the right thickness, the best way to cut it and a long etc... that would make most loose interest. But still light seals are a minor repair one can do at home with little work that can breathe new life to their leaky camera.
As the last cameras made are getting past their teenage years their foam is starting to degrade leaving a mix of gunk and foam dust nobody wants on their mirrors or film. And as we can't replace all the light seals in the world on our own, we decided to source the best foam we endorse and have it available to purchase, this took us a few years and at least a few dozen different materials.
And to go with it made a video tutorial on the steps to take for changing light seals properly like we do here at the Rescue Center.
This guide will give you some insight on how to go about removing the old light seals properly, and then replacing them.
We recommend you read this entire article once over before attempting the procedure yourself, and then using this as a step by step guide.
To get started you will need…
A camera in need of light seal replacement!
Industol - A solvent for getting rid of the remnants of the old light seals
1mm - 1.5mm thick non adhesive backed open cell foam
This is for the film door light seals
3mm thick adhesive backed open cell foam or adhesive backed felt
For the back door hinge and mirror bumper (if needed)
Contact Cement (we use Kiilto Tixo although any all-purpose slow setting contact cement should do) – DO NOT USE SUPERGLUE!!!
Rotary Cutter or craft knife
Wooden skewer and lollipop(Popsicle) sticks
Kimtech / lint free tissues
A couple of syringes for delicate application of solvents and glues
Masking tape to protect the shutter
A microfibre cloth and some foam cleaner to clean the camera itself
Now that we have all the necessary materials collected we can get onto the main event!
The first thing to do is open the back and mask off the shutter, taking care not to get tape stuck to the shutter itself!
Next, using the syringe, carefully apply a sparing amount of industol to the light seals to soften them up. Wait a few moments and then start to scrape out the old light seals using a lollipop(popsicle) stick which has been cut at an angle.
Wipe the residue off the lollipop stick using a lint free tissue. Repeat this step until the all residue is cleaned away. Cue tips can be useful to clean any residue from beside the hinge of the back door. On some models the back door might be easily removable.
It is very important to thoroughly remove the residue. If the surfaces aren’t clean this may lead to the new light seals not sticking properly.
Now that the camera is clean, you can start measuring and cutting the new light seals.
Start with the lengthwise strips out of 1-1.5mm open cell foam. Measure, or estimate, the width required for the channels. Try to get it the same width or slightly wider than the channel. Then, using a ruler as a straight edge, carefully slice along the edge using a rotary cutter or craft knife. You will need two of these strips.
Using a syringe, apply the contact cement along both channels for the light seals sparingly. Take your time with this step, the contact cement won’t dry out too quickly.
Once the cement is applied, take one of the light seal strips. Starting from one edge, push the seal into place using a wooden skewer stick to help you. Once in place, use a skewer to press down on the seals to ensure they are firmly in place.
On most cameras there is a notch along the channels which detects if the back door is closed and engages the film counter. Make sure not to cover this notch with the new light seals or your frame counter will not work.
The next step is to apply the hinge light seals. Make a note of the locations of the old material as you will want to replace the new material in the exact same positions. Select the correct material depending on what was there before, usually either foam or felt.
Estimate and cut a strip to size, and apply the new material in place of the old material.
Most cameras have a mirror bumper made of the same foam as the light seals, and as such also need replacing. Use some solvent very precisely to soften the bumper foam and pull it away using some tweezers. Take care not to get any of the solvent on the focusing screen as it will damage it irreversibly. Once the old mirror bumper foam has been removed, cut a thin strip of the 2mm adhesive backed foam to size and place it where the old one was. Take a look through the viewfinder to make sure the new bumper is not obscuring your sight, and test the shutter on bulb mode to make sure the foam is catching the mirror.
Once all seals and bumpers are installed, try closing your camera. It should close nicely. If you notice that something is getting caught and stopping your camera from closing, trim it.
The next test is opening your camera. The back door should spring open. Once again, if you notice anything getting caught, trim it until it opens and closes smoothly.
Cleaning the camera 📷
After all of that work it's probably necessary to give the camera a thorough cleaning.
Before we use any wet cleaners it's a good idea to brush any dust from around the knobs and corners using a toothbrush.
Here at camera rescue we use a foam cleaner on all the external surfaces of the camera. Spray a bit out into a smaller container and then scoop some up onto the toothbrush. Gently clean all the surfaces. The leatherette usually requires some extra attention.
Take care not to get the cleaner on any optical surfaces as it will leave behind a residue.
To clean the viewfinder element and the mirror, use a cue tip and condensation from your breath to gently wipe away any dust which has settled on the surfaces. If there is any stubborn dirt on the mirror or eyepiece you can use a small bit of lighter fluid to break it up.
Hopefully now you should have a clean and light leak free camera ready for another few decades of use!