Removing old or unsuccessful repairs

Repairs done by using a vinyl patch and common vinyl glue are known to be permanent. The glue is usually polyurethane filler diluted by MEK and acetone and such repairs are known to be permanent when stick together.

Even though sometimes we need to remove the patch and apply a new one. This can be due to part of the patch is starting to peel off after a few years on over exposed places because the PU glue degrades quickly or simply because we want to make the repair better.

This method can be applied on both occasions.

The main trick is to get pure MEK, Methyl eltyl ketone or butanone, cheap chemical you can buy in a model train shop or ebay.

When using a paintbrush with MEK you can start to peel off the patch with constant pouring little amount of MEK right between the patch and main material. Once the liquid MEK dilutes the closest layer of glue the patch starts to peel off with not much force needed.

After removing the whole patch you can just clean the place using ethanol or isopropylalcohol. If the remaining layer of old glue is too thick you can remove it gently by MEK too but don't expose the vinyl to MEK for too long.

MEK makes the vinyl soft and weak when touch but don't dissolves it much. When you rub vinyl with MEK you can damage the texture for example but not the whole material. So when an unwanted exposition happen just remove it gently and wait for a few hours for MEK to evaporate from the inside of the material, don't touch or rub the place until it will get the previous shape.

Warning: MEK is a pretty strong thinner so you don't need much prolonged contact with your skin until you clean it off by water..

MEK is useful chemical for other purposes also. As for model train buildings the same technique is applicable on most of those "computer's plastic" casings, for removing toner from home made pcb's etc..

Proper care of inflatable toys

Cleaning
The toy needs cleaning after each prolonged contact with our skin. Whether it is in water or at home. Use lukewarm water only and dry paper towel for regular cleaning and nanosponge for major cleaning.

Getting rid of smells
Use nanosponge and lukewarm water. It removes all the microscopic dirt on the surface of the vinyl. When using nanosponge regularly, there is absolutely no recognizable smell on exposed parts even after years of usage.

Cleaning dirty/found toy
Use natural beach, sodium percarbonate dissolved in hot water to remove all the dirt, then use water to remove the bleach. the last step is again the nanosponge to remove the smell.

Cleaning inside
When the toy needs cleaning form the inside, it is also possible. For example warm distilled water quickly removes everything water soluble with no residues and no harm to vinyl. The key is proper drying after doing this. It is simple. Hang the toy vertically with valve on the lowest place for a few hours to let all droplets to go down and out the valve. Then left the toy inflated and change the air using electric pump twice a day for about week to make sure there is no recognizable humidity in the air escaping through the valve.

Drying after mouth inflation
Mouth inflation of your favorite toy gives you an intensive impression but to do it every time is really bad for the toy. Please use hand or electric pump at least 20 times more than doing the mouth inflation and the toy will be safe. The best option is to apply the drying process above soon after the mouth inflation especially if you know the toy will sit deflated longer. Never put the toy on the sun to dry itself, it only degrades the material and printed colors.

Replasticizing
Use ATBC or other possible non-toxic plasticizer in a liquid state to apply directly on places that became rigid after prolong contact such as places where you place your face often. Also apply plasticizer along the pinched seams to prevent small cracks using paintbrush.
Use mixture of 90 % of IPA and 10 % of ATBC to apply on painted areas of the toy to prevent melting the printed color with pure ATBC. When most places of the toy needs to be replasticized, use 10ml of ATBC for 1 square meter of the vinyl from the inside of the toy. Apply it when the toy is inflated through the valve and spread the liquid to desired places. Than deflate the toy and continue spreading while rubbing the sides of the toy. Soaking takes time, at least a week for pure ATBC used inside. Unevenly spread plasticizer causes little waves on vinyl these will however disappear after a few more days when the plasticizer spreads further along the material.

Repairing
Use glue for flexible PVC only. It's cheap, easy to obtain and works perfectly. Prefer those that contain MEK, acetone and polyurethane. The glue itself has pretty low shear strength so a patch is needed every time. Use patching material with the same thickness as the toy has. Keep the application manual on the glue called a contact method. Apply the patch from the outside or inside if you like. Usually the patch needs to be 10 – 15 mm wide strip that is 10 mm longer than the tear or seam split. There is no tear or seam split the glue can't repair even when the toy needs to be completely rebuilt.

Cleaning glue residues
Drops of glue goes off using IPA when caught immediately. When it is too late use mixture of 1/3 MEK and 2/3 alcohol on a towel. The added alcohol makes the mixture less harmful to your hands Work with pure MEK carefully.

Removing unsuccessful repairs
Use mixture of 1/3 MEK and 2/3 alcohol applied to the edge of the repair using paintbrush. When it starts to peel off continue adding the mixture under the patch to make the peeling off easier. Later remove the rest glue on the toy using towel with the same mixture.

Occasionally inflated toys
Make sure the toy is clean and dry before storing it for longer time. Isolate black handles from the vinyl using towels to prevent color transfer. Fold them the way delicate printed places such as eyes are on flat surface. Avoid sharp corners by more rolling the toy instead of folding sharply. Try to fold the toy differently than previous one, don't let it to match the old folds. This prevents the classic pinched seams that tends to crack in repeatedly folded corners.

Storage
When folding the toy avoid sharp corners especially on important places such as eyes and snout of animal pool toys. Never put the toy into a cardboard box without a separator, PE foil for example. The wall of a cardboard box works like a sandpaper when the toy is moving inside the box and causes scratches and sometimes even leaks on sharp corners at the worst case. The smell transfers easily, put similar toys together. Avoid contact with aggressive materials like rubber, latex, TPE or ABS plastic, they transfer the color causing black marks or makes the vinyl brittle. Also avoid contact with printed bags, laser printed papers. Especially overplasticized IW toys dissolves and absorbs these colors very quickly, in hours.

Stable inflated toys
Use lower pressure for toys intended to stay a long time for display. Atmospheric pressure and temperature changes volume of air inside a lot. 10 hPa rise means there is 1 % of air missing inside the toy. Check atmospheric pressure forecast. Vinyl which is stressed for a long time becomes thinner the same way toys gets when heat stretched. That is because the tensile strength curve for flexible PVC is not the same for long-term stress. Avoid plastic deformation by keeping your stable inflated toys at low pressure. These standing on four legs or having long heavy tails help by adding another toy or furniture below them so they don't need to support themselves with high pressure.

Toys near water
The most significant when near water is to avoid heat stretching and fading of painted colors on direct sunlight. Inflate the toy only little when it has to be put on a sunlight without you floating on. When you're floating on the toy is cooled by the water and the temperature inside is much lower compared to when the toy sits on water or worse out of water alone. When you go out of the water take the toy with you to the shadow place. It is ok for the toy to look deflated when you go out of the water. The vinyl will contract quickly and the air temperature and pressure will rise in a minute and your toy will look fully inflated again. Never inflate the toy when you went out of the water realizing the toy is deflated, let the vinyl contract itself and the air to heat up again. Sit next to the toy and put your hand on supplying the missing air volume for a minute until your dragon will hold the head up again.

Toys in winter time:
Older phthalate toys were more tolerant toward low temperatures than today's ones which can suffer seam splits when inflated and loaded below 15°C. On the contrary InflatableWorld.de toys for example can withstand freezing temperatures with no troubles because of their thin vinyl and it's unusual flexibility.

How to get
nanosponge – households stores, sometimes called Magic Eraser
natural bleach, sodium percarbonate – BIO/ECO natural stores, it is used as a nature friendly washing powder.
IPA, ethanol – hardware stores
MEK – model train shops, it is used as a base for their glue
ATBC – Use Sculpey Clay Softener or ask your friend at chemistry lab or university to buy it for you or ask Chinese factories for low amounts or samples.

Never give up
Always try to sell the toy you no longer want to anyone else to give the toy a new home. Most of them will become expensive collectibles doesn't matter the condition in a few years after the end of production.

81 years of nessies, the most beautiful creatures!

A short video

Someone asked me to make a short video showing the plasticized vinyl with ATBC soaked inside.
http://www.youtube.com/watch?v=q6WoiNANBO4

Winter Nessie

Modrá nessie s ručně pletenou nebelvírskou šálou kolem krku. Chtěl jsem pro ni něco ze světa HP, který mám tolik rád, ale investice do filmových replik mě moc nelákají, tak jsem místo toho koupil klubíčka. Bylo to docela dost práce vzhledem k tomu, že jsem nikdy dřív nepletl, ale byla to svým způsobem hezká práce. I dvoumetrová šála však kolem jejího krku vypadá krátká.