Thread: Adventures with acetone

Some things I have learned through trial and error in the last few days.

1) A No 2 or No 3 brush is the perfect applicator. Although a cheapie with synthetic bristles is plenty good enough, no need to buy a sable brush. You can get a pack of 5 or 6 brushes for $2 without any trouble.

2) Acetone will glue together a celluloid scale that has been snapped in half (this was the error part of 'trial and error'). Careful sanding and painting will make the join hardly noticeable, but not invisible. All you have to do is lightly paint each end with acetone and gently push the ends into place and then let them sit whilst supported for 15 minutes and you will have a solid join. Solid enough to re-pin a razor within 30 minutes of joining the two halves together if you are like me and have no patience.

3) Using a brush dipped in acetone to get underneath inlays as they start to lift is a very efficient way of removing metal inlays without damaging them.

4) You can glue inlays into new celluloid scales using acetone. Firstly you clean and shape the inlay for the new scales. Then liberally paint the back of the inlay with acetone. Quickly place the inlay into position on the new scales and lightly but firmly press the inlay against the scale. Use your fingernails or toothpicks to hold the inlay in position. After about 30 seconds the acetone will have melted the celluloid around the inlay and re-set. This leaves the inlay set into the side of the scales.
I would suggest that you use masking tape to mask off the area where you want to fit the inlay.
If you goof up you can use acetone to lift off the inlay, wait for the celluloid to dry out, sand the scar back with 1500+ sandpaper and try again. It's better not to goof up, but if you do it isn't the end of the world.

Excellent post. Now I can't wait to have the opportunity to give this a test ride. I just love to find these little technical tips to add to my own bag of tricks. Thank you for the help with plastic. I'm not all that fond of that stuff but we do have to bother with it in this day and age.

Very Respectfully

Chasmo

Pauly,

Could you post some pics of he finished product, would be interested to see how it went. Thanks for posting. Look forward to some pics.

Sweet tip, thanks for sharing!

Regards
Louis.

Acetone works OK with celluloid, but it does not give a full strength solvent weld. Nor, in my opinion does it disappear cracks as well as other chemicals. I use MEK on celluloid fountain pen repairs and it is much better than Acetone. There is another solvent which does give a full strength weld, but it is not available to the general public and is exceedingly toxic to use.

I have been repairing celluloid fountain pens for 6 years and have found that cracks welded with acetone are not as strong as MEK welded joints. I very strongly suggest against using any cyanoacrylates on celluloid as they just don't have the long term holding power of a good solvent weld. Also super glues are hygroscopic and will eventually fail when subjected to water (as razors often are).

The OP's suggestions are excellent, but I would rather wait at least 24 hours (a week is better) before working on any solvent welded joint. This ensures that all solvents are flashed out of the material and the weld has properly set.

Cheers,
Sean

I've lost one inlay to a tight fitting box, so the idea of letting them cure for a week is a damn good one.

Where does one get MEK?

Originally Posted by SMG

Acetone works OK with celluloid, but it does not give a full strength solvent weld. Nor, in my opinion does it disappear cracks as well as other chemicals. I use MEK on celluloid fountain pen repairs and it is much better than Acetone. There is another solvent which does give a full strength weld, but it is not available to the general public and is exceedingly toxic to use.

I have been repairing celluloid fountain pens for 6 years and have found that cracks welded with acetone are not as strong as MEK welded joints. I very strongly suggest against using any cyanoacrylates on celluloid as they just don't have the long term holding power of a good solvent weld. Also super glues are hygroscopic and will eventually fail when subjected to water (as razors often are).

The OP's suggestions are excellent, but I would rather wait at least 24 hours (a week is better) before working on any solvent welded joint. This ensures that all solvents are flashed out of the material and the weld has properly set.

Cheers,
Sean

Sean,

Thanks for the acetone advice, much appreciated.

Originally Posted by Pauly

I've lost one inlay to a tight fitting box, so the idea of letting them cure for a week is a damn good one.

Where does one get MEK?

Not sure where you would get it in Queensland, I got mine from an old job I had where they had a large paint booth. Methyl Ethyl Ketone is MEK, its not great for you by any means, but does work wonders on celluloid and other plastics.

Try autobody paint suppliers, it is a type of paint thinner. Just make sure that you wear a respirator when handling it. While it smells very sweet, it kills brain cells rather quickly.

Cheers,
Sean

additionally, you can melt celluloid in MEK (or acetone) and paint the resultant mixture onto celluloid to build up missing pieces, torn out chunks etc.

Celluloid dents can be easily removed, but you need to know what you are doing. I remove teeth marks from celluloid pens regularly, and when I am done normally you cannot see that there were marks there to begin with. But this only works when the base material is indented, and not torn out. Removing dents in celluloid is dangerous, probably moreso than solvent welding so I would rather not describe it in too much detail here.

I have used the melted celluloid/MEK mixture to build up missing parts from pens, weld barrels together, fill in personalizations. Its pretty amazing what you can do with that stuff really.

Cheers,
Sean

I just received a pair of razors in the mail yesterday. They both need a lot of work. I was going to have to throw out a pair of scales which were in prefect condition apart from being snapped in half. I will give the acetone repair a go.