Celluloid problem

[jakubko123]

Hi guys!
I wanted to fix major missing celluloid area on my accordion, so i disolved some celluloid in acetone based liquid (diluent c 6000). Everything was looking great, celluloide disolved properly so i spread it on the accordion generously and i let it sit. After some time i saw that the acetone from celluloid mixture disolved the body of the accordion which is made out of some plastic i guess, and this disolved plastic came to the surface. I tried to cut out the plastic and repeat the proces but it does not work very well and the yellow plastic keeps leaking on the surface.
Here are photos 1. First spread 2. Plastic disolved 3. I cut certain parts and put another celluloid in the gaps 4. It keeps leaking!
Another problem is that even if i put a generous amount of celuloid in the gap, after the acetone evaporate it left only very thin layer of celluloid
Please send help thank you for your tips

 

[jakubko123]

Is it bad idea to stick a raw piece of celluloid on and fill the spaces with some disolved ?

 

[Dingo40]

Welcome Jakubko!
Sorry, I don't know the answer to your excellent questions, I just wanted to bump your post.
Perhaps someone with experience will soon chime in?

 

[Ikesaccordions]

Is it bad idea to stick a raw piece of celluloid on and fill the spaces with some disolved ?

It won't work. I've tried it on small defects using fingernail polish which is about the same. The whole accordion could be re-painted like you would paint a car.

 

[Dingo40]

I have a small, black Pancordion which may have been standing too near a radiator, causing some patches of celluloid to bubble and come away.
It was repaired ( many years ago, before I got it) simply by tidying up the damaged area and painting the exposed underlying wood with a matt black paint or stain similar to "kickboard" paint used to paint the kickboards along the footing of kitchen cabinets.
It's still good, invisible from a short distance, decades later.

 

[debra]

I have successfully done celluloid repair without any of the problems you showed. The first thing you need to ensure that you use real acetone. What is sold as "diluente" (thinner) is not pure acetone. I read that in accordion production they also used a 50/50 mix of acetone and water, but no other chemicals should be in the mix.
At this point your best bet is to remove everything from that whole side of the accordion and put new celluloid on that you soften in acetone (make sure you have enough ventilation to remove the toxic fumes) and then put it on. The acetone then needs to sit and harden for at least 24 hours before you start sanding and polishing. But you probably have to do some touch-up work at the seams before sanding as well.
I find celluloid quite easy to work with, but you 1) need to treat it with just acetone, nothing else, and 2) you must avoid putting heat in it (for instance with excessive force while sanding) as it is quite flammable.

 

[Ikesaccordions]

I have successfully done celluloid repair without any of the problems you showed. The first thing you need to ensure that you use real acetone. What is sold as "diluente" (thinner) is not pure acetone. I read that in accordion production they also used a 50/50 mix of acetone and water, but no other chemicals should be in the mix.
At this point your best bet is to remove everything from that whole side of the accordion and put new celluloid on that you soften in acetone (make sure you have enough ventilation to remove the toxic fumes) and then put it on. The acetone then needs to sit and harden for at least 24 hours before you start sanding and polishing. But you probably have to do some touch-up work at the seams before sanding as well.
I find celluloid quite easy to work with, but you 1) need to treat it with just acetone, nothing else, and 2) you must avoid putting heat in it (for instance with excessive force while sanding) as it is quite flammable.

You are correct, but what the OP seems to have done is dissolve celluloid in a liquid, rather than apply a sheet of it.

 

[debra]

You are correct, but what the OP seems to have done is dissolve celluloid in a liquid, rather than apply a sheet of it.

But I have also done that. Especially for smaller repairs I have dissolved celluloid until it became a paste and smeared that out. Initially the surface is not smooth, but sanding (after it's completely dry, at least 24 hours later) took care of that. For a large area like what the OP had just softening a sheet of celluloid and then softly pressing it using a rubber roller is the better approach. The seams can be filled in with a celluloid paste. I have yet to see disastrous results like those of the OP.

 

[Gonk]

Only certain types of plastic are dissolved / damaged by acetone, and even then, usually they only soften, rather than dissolve like this. I think this is a problem with your solvent. As Paul De Bra said, use only pure acetone. It can be found at any hardware store.

If you have more black celluloid on hand, I would suggest you sand down the damage and try again, using acetone. Apply thin layers (not generous), let them cure, and sand them with fine sandpaper wrapped around a wooden block to level areas that are getting high. Repeat this process until you have a flat black surface, then go up the grits and buff it. Buff slowly and avoid pressing hard or creating heat on the surface.

 

[32251]

Celluloid patches where you make a paste, should only be done on very small cracks or damaged areas. This is way too large an area to ever hope the paste would work. This should have been done with a sheet of celluloid. The ends could have been rubbed together with duco cement and that would have melted the ends of the celluloid together and after sanding you might not even be able to see it. This repair was never going to work. When you make the celluloid paste you use straight acetone. Btw, duco cement contains acetone, camphor and cellulose nitrate……some of which is in celluloid. I have used this glue for celluloid for decades.

 

[KiwiSqueezer]

I'm interested in where this thread is going, because I will have to face similar celluloid repairs in the future. I cannot add anthing to what has already been said about the application of sheet celluloid because I'm still trying to find out enough to have the courage to attack a large-area repair. I have some experience of working with some plastics, but not celluloid, so what follows is not the result of (bitter) experience.

The OP's concern about the plastic substrate being attacked by solvent hasn't been addressed. It seems to me that, if indeed it was the acetone in the solvent he used that attacked the substrate, it will do so again, when acetone - or acetone-based material - is used to stick down celluloid sheet. Therefore, I think there should be some attempt to make a barrier layer between substrate plastic and wherever acetone is going to be used. Whilst epoxy is slowly attacked by acetone, I'd suggest that a thin layer of epoxy, painted on the plastic, would provide a good-enough chemical barrier. Of course, one would have to ensure that none of the epoxy layer was high enough to prevent the new celluloid from lying at roughly the right level, so some additional abrasion of the substrate might be necessary. Also, it looks like the substrate surface needs to be made smooth - another job for the epoxy. I'd think that the epoxy should be scuffed up before trying to stick anything to it.

 

[Ventura]

first, KiWi is right.. have to address the vanishing accordion body issue

note: Styrofoam variants wither under acetone like the Wicked Witch of the West

on one hand *apologies to you Jakubko, but is any plastic bodied accordion
worth fixing up ? and then i have to allow that sometimes you have to work with
what you got, because that is all you got.

so if i were going to make a fix, i would remove the rest of the celluloid
from that area of the body.. the entire section bare and clean..sand it roughly, then get a
can of Automotive Body Putty (here we call it Black Magic) and mix some up
and trowel it on filling up the damaged area and adding a nice smooth
thin layer to the rest.

Body Putty sands easily and is very strong, so you can use files and
sandpaper to make it nice and flat again. This stuff sticks to anything
and cures by catalytic action. If you put it on extra thick and have a fine cheese grater,
you can smooth it down most of the way when it is still curing and somewhat soft.
You can layer this material several times if you need to.

then just paint it with a latex paint because the Volatile component of
typical spray paint can also attack Styrofoam type plastics, so i would
NOT use a solvent based paint as any overspray might attack another
section of the body

Jakubko, why did you decide to fix this accordion up in the
first place ? was it nice to play ? what brand and model was it ?
do you have other accordions available to you ?

best wishes

 

[KiwiSqueezer]

Just be careful to find out what the body filler's resin base is. Many (most?) are/were polyester resin based, and will be readily attacked by acetone.

The next question the OP must be wondering has to be 'What was used originally to stick the celluloid to the plastic casework?'. As far as I have been able to discover, softened celluloid either self-adheres to (wooden) casework, or is 'stuck' with acetone introduced between the celluloid and the casework. In the latter case, presumably it softens the undersurface of the sheet celluloid sufficiently to make the a thin layer of the surface into an adhesive paste. But then one wonders about its subsequent evaporation. Presumably celluloid is 'porous' to acetone, to some extent. Please can someone enlighten?

The whole business of working with celluloid seems fraught with hazard. I'm just hoping that I can find out enough to reassure me that ordinary mortals can effect satisfactory repairs...

As an aside... In the 'good old days', it was fun to work with Perspex (acrylic), solvent-welding it together with chloroform. Nowadays, I expect that if you were to go into a chemist and ask for chloroform, you'd get a very funny look. Methyl ethyl ketone (MEK) is an excellent solvent for polystyrene (and other) plastic, and is/was extensively used by the plastic model makers. I went to a local paint and printing ink makers, some time ago, on a recommendation, and innocently asked for a small quantity. The reaction of the staff was bizzarre. It was as if I had done something seriously immoral. I put on my best innocent, befuddled, harmless old man act, and finally persuaded the staff that I just wanted it to repair a broken plastic component in some scientific apparatus - which was the truth. They were mollified. Apparently, it's used in the manufacture of illegal substances. I was presented with a small bottle. No payment was accepted, because they were, apparently, not allowed to sell the stuff to the public. I offered to donate a few $$ to their coffee fund, but that was graciously refused. I think they just wanted me out of the place, presto. I have since discovered that the primer, used before the solvent adhesive, for PVC pipe welding (as in home plumbing) is essentially methyl ethyl ketone. You can buy it without restriction. The world has gone mad...

Incidentally, I think that MEK works well on celluloid, but haven't tried it. It's more volatile than chloroform, which may be an advantage in some applications.

 

[32251]

Just be careful to find out what the body filler's resin base is. Many (most?) are/were polyester resin based, and will be readily attacked by acetone.

The next question the OP must be wondering has to be 'What was used originally to stick the celluloid to the plastic casework?'. As far as I have been able to discover, softened celluloid either self-adheres to (wooden) casework, or is 'stuck' with acetone introduced between the celluloid and the casework. In the latter case, presumably it softens the undersurface of the sheet celluloid sufficiently to make the a thin layer of the surface into an adhesive paste. But then one wonders about its subsequent evaporation. Presumably celluloid is 'porous' to acetone, to some extent. Please can someone enlighten?

The whole business of working with celluloid seems fraught with hazard. I'm just hoping that I can find out enough to reassure me that ordinary mortals can effect satisfactory repairs...

As an aside... In the 'good old days', it was fun to work with Perspex (acrylic), solvent-welding it together with chloroform. Nowadays, I expect that if you were to go into a chemist and ask for chloroform, you'd get a very funny look. Methyl ethyl ketone (MEK) is an excellent solvent for polystyrene (and other) plastic, and is/was extensively used by the plastic model makers. I went to a local paint and printing ink makers, some time ago, on a recommendation, and innocently asked for a small quantity. The reaction of the staff was bizzarre. It was as if I had done something seriously immoral. I put on my best innocent, befuddled, harmless old man act, and finally persuaded the staff that I just wanted it to repair a broken plastic component in some scientific apparatus - which was the truth. They were mollified. Apparently, it's used in the manufacture of illegal substances. I was presented with a small bottle. No payment was accepted, because they were, apparently, not allowed to sell the stuff to the public. I offered to donate a few $$ to their coffee fund, but that was graciously refused. I think they just wanted me out of the place, presto. I have since discovered that the primer, used before the solvent adhesive, for PVC pipe welding (as in home plumbing) is essentially methyl ethyl ketone. You can buy it without restriction. The world has gone mad...

Incidentally, I think that MEK works well on celluloid, but haven't tried it. It's more volatile than chloroform, which may be an advantage in some applications.

Think about it. Celluloid was originally glued to the substrate. That means that the glue used only provided enough melting together of the two to adhere it. The celluloid paste was too concentrated for the substrate. A layer of glue will not destroy the substrate. It will just melt the two together. A thin layer of glue with medium.clamp pressure will work. Just be aware that the celluloid layer will show any imperfections in the substrate it’s glued to. I recommend doing a small test area first. If it works then sand it level before application of the larger area.

 

[Ventura]

amd what would you suggest to fill the eaten away area ?

we have no real clue what kind of plastic this beast is, we only
know it isn't very stable under acetone stress at all

who knows what their original process was, or how they accomplished it,
are we even sure the original finished surface IS cellulose ? maybe it is some other type
of plastic stuff too. How was the body originally formed ? roto mold ?
poured ? pressed ? machined out of a big block of plastic ?

the keybed looks evacuated too, i can't see any structure in the pics
at all.. looks almost like he put a new piece of plywood in for the keybase
but where is the rake the pivot rod goes through ?
all i see is a bit of leftover felt..

i still say use Bondo.. dat shit sticks to everything with a deathgrip..
i have even patched spalls on my concrete driveway with it..

i feel trying to continue with normal and typical accordion repair methods
and materials will just make things worse..

we really need to hear more from the OP

 

[32251]

amd what would you suggest to fill the eaten away area ?

I would use a black auto bumper repair kit for plastic bumpers. It’s probably just some kind of two part epoxy. Takes paint nicely, or the black color might blend in fine when sanded and buffed.

i still say use Bondo.. dat shit sticks to everything with a deathgrip..
i have even patched spalls on my concrete driveway with it..

I had a sitar that the gourd was eaten up by insects. Bondo worked a miracle.

 

[JKJ]

I agree with the suggestion to consider a body putty or filler such as Bondo or similar. These can stick to nearly any clean surface and can easily be sanded, smoothed, primed and painted. They are primarily a resin which is mixed to a hardener, a type of epoxy. Some also contain fillers such as fiber (glass), metal powders, and ceramics. You can find a lot of info on the web or just stop into your friendly local automobile body repair place and ask for advice. (A good auto-parts store that caters to the professionals might provide good advice on which product to use. Different types are for different repairs, for example some are flexible, not needed for the accordion surface shown. I’d probably choose one with a relatively long workingtime. Here is one instructive resource page that came up in a quick search:

https://www.autobodytoolmart.com/bo...und the damaged area,, wet, or humid surfaces.

The stuff will generally stick to anything but it must be clean and dry. Hard to tell from the photos but if there is any loose substance from the dissolved plastic, it might be best to use something like a narrow woodworking chisel and cut down to a solid surface. Sand to roughen, then perhaps use a sharp cabinet scraper to flatten the surface before applying and smoothing the filler.

After the filler has hardened, smoothed, and sanded to a fine grit it can be primed and painted. With proper prep, paint, and polish I think the result could look just like the undisturbed celluloid surfaces on the rest of the accordion. (If nervous about tackling this you might look for an experienced automobile body repair person to do the repair after work hours - might take a few days to achieve a professional mirror finish on the afffected section. Good auto people are experts on making things look perfect).

As well as repairs, body fillers like these are often used in some unusual products. For example, I have a Kubota excavator that has what looks like a smooth steel wrap-around rear “bumper” which is really a large and incredibly heavy solid cast iron counterweight! The surface of cast iron is by nature is often quite rough and coarse and that’s obvious when looking at it from the inside the engine compartment. However, as delivered new, the outside surface of the casting was beautifully shaped and smooth, painted to match some of the other forged and machined steel parts on the equipment. In heavy use around large rocks I often beat up the machine and scraped the surface of the counterweight in one place, through the paint and down to the cast iron surface - this revealed over 1/8” thick layer of bondo-type filler which had been smoothed, sanded, and painted to look like smooth steel. (Quite easy to fix such a cosmetic gouge if I were so inclined. But I don’t care much - I didn’t buy the machine to prissy around in the yard and keep polished to impress the neighbors. )

Just for fun, here’s a photo of one of the rocks I dug up with the little excavator. My son is standing near it for scale. That rock was sticking up about 6” too high for the way I wanted to shape the ground there behind the house.. It took a while but in the end, hydraulic power prevailed and the thing is out of there. No way I oould lift the thing but I pried it out of the hole with the skedsteer. Anyone want a big rock? Bring a big trailer.

JKJ

 

[Dingo40]

or just stop into your friendly local automobile body repair place and ask for advice.

Or...just get them to do the whole job?
(I've had our local body shop respray some vintage metal children's furniture: well worth it!)

 

[Dingo40]

Just for fun, here’s a photo of one of the rocks I dug up with the little excavator.

Good thing it didn't turn out like this one!

Google Image Result for https://t3.ftcdn.net/jpg/03/12/66/94/360_F_312669404_VgQ6iCrYetDDmoG0wEq0uIWFAVyqrosC.jpg

 

[Tom]

I agree with the suggestion to consider a body putty or filler such as Bondo or similar. These can stick to nearly any clean surface and can easily be sanded, smoothed, primed and painted. They are primarily a resin which is mixed to a hardener, a type of epoxy. Some also contain fillers such as fiber (glass), metal powders, and ceramics. You can find a lot of info on the web or just stop into your friendly local automobile body repair place and ask for advice. (A good auto-parts store that caters to the professionals might provide good advice on which product to use. Different types are for different repairs, for example some are flexible, not needed for the accordion surface shown. I’d probably choose one with a relatively long workingtime. Here is one instructive resource page that came up in a quick search:

https://www.autobodytoolmart.com/body-filler-howto#:~:text=Paint around the damaged area,, wet, or humid surfaces.

The stuff will generally stick to anything but it must be clean and dry. Hard to tell from the photos but if there is any loose substance from the dissolved plastic, it might be best to use something like a narrow woodworking chisel and cut down to a solid surface. Sand to roughen, then perhaps use a sharp cabinet scraper to flatten the surface before applying and smoothing the filler.

After the filler has hardened, smoothed, and sanded to a fine grit it can be primed and painted. With proper prep, paint, and polish I think the result could look just like the undisturbed celluloid surfaces on the rest of the accordion. (If nervous about tackling this you might look for an experienced automobile body repair person to do the repair after work hours - might take a few days to achieve a professional mirror finish on the afffected section. Good auto people are experts on making things look perfect).

As well as repairs, body fillers like these are often used in some unusual products. For example, I have a Kubota excavator that has what looks like a smooth steel wrap-around rear “bumper” which is really a large and incredibly heavy solid cast iron counterweight! The surface of cast iron is by nature is often quite rough and coarse and that’s obvious when looking at it from the inside the engine compartment. However, as delivered new, the outside surface of the casting was beautifully shaped and smooth, painted to match some of the other forged and machined steel parts on the equipment. In heavy use around large rocks I often beat up the machine and scraped the surface of the counterweight in one place, through the paint and down to the cast iron surface - this revealed over 1/8” thick layer of bondo-type filler which had been smoothed, sanded, and painted to look like smooth steel. (Quite easy to fix such a cosmetic gouge if I were so inclined. But I don’t care much - I didn’t buy the machine to prissy around in the yard and keep polished to impress the neighbors. )

Just for fun, here’s a photo of one of the rocks I dug up with the little excavator. My son is standing near it for scale. That rock was sticking up about 6” too high for the way I wanted to shape the ground there behind the house.. It took a while but in the end, hydraulic power prevailed and the thing is out of there. No way I oould lift the thing but I pried it out of the hole with the skedsteer. Anyone want a big rock? Bring a big trailer.

JKJ

Nice rock! I’ll trade you a B Griff for it, but you gotta deliver. I had similar fun putting in my yard here, but none that big. We have granitic and gneiss erratics over limestone bedrock, some as large as yours. I’ve got limestone rocks that big where the bedrock rises to the surface. Big business a few years ago when all the retired dentists had to buy new riprap when the lake rose. I think the erratics have a tremolo of about 25 cents when in cassotto. Very Scottish.