A few years ago I made a replacement cover for my turntable from acrylic glass using pure DCM as a solvent. It looked nice in the beginning but after few months the net of cracks started to develop in joints. Basically the joint itself, the very thin layer of dissolved polymer, started to shrink. What did I do wrong? Can it be attributed to the quality of the material? Can adding a small amount of acrylic to the solvent prevent this? I want to redo it.
Wrong 'un.
DCM is the solvent recommended for Polycarbonate, and can be added to epoxy resin to repair Polycarbonate.
There is no such thing as acrylic glass.
Use Chloroform, with a brass/ glass syringe / artist's brush, do some scrap trials first, as just the right amount has to be applied to prevent stains.
Plastic syringes are NOT recommended, as the material can contaminate the solvent used.
You can try a simple repair, put the thing in an air circulating type oven at about 80 Celsius for two hours, then switch off heat, let fan run till 60 C.
Then let cool without power.
Should see less cracks, and at least they will not increase as time goes by.
Such ovens are common in plastic factories, and as incubating ovens in pathology labs, among other places.
DCM is the solvent recommended for Polycarbonate, and can be added to epoxy resin to repair Polycarbonate.
There is no such thing as acrylic glass.
Use Chloroform, with a brass/ glass syringe / artist's brush, do some scrap trials first, as just the right amount has to be applied to prevent stains.
Plastic syringes are NOT recommended, as the material can contaminate the solvent used.
You can try a simple repair, put the thing in an air circulating type oven at about 80 Celsius for two hours, then switch off heat, let fan run till 60 C.
Then let cool without power.
Should see less cracks, and at least they will not increase as time goes by.
Such ovens are common in plastic factories, and as incubating ovens in pathology labs, among other places.
DCM will cause disintegration of the plastic, it has started, those big marks are characteristic.
Which is why I said do a heat treatment cycle in oven.
If you do not use excess quantity of Chloroform, and work in a well ventilated area, it is safe.
Chloroform was used as an anesthetic for my tonsils surgery in 1973, I am still around....
No point in tinting.
Which is why I said do a heat treatment cycle in oven.
If you do not use excess quantity of Chloroform, and work in a well ventilated area, it is safe.
Chloroform was used as an anesthetic for my tonsils surgery in 1973, I am still around....
No point in tinting.
Make sure your supply of chloroform is fresh or has been securely stored. It degrades on exposure air forming phosgene. Which you really don't want to inhale. IIRC, in the early years of use of chloroform there were fatalities from phosgene contamination.
Not saying don't use it, just take precautions...
I buy it from a chemical supplier saying it is needed for solvent bonding.
He gives me the correct quality.
There are levels of purity and moisture content, as you pointed out.
It is a small indudtry here, medical chambers and such, and less than ten sellers, so a common item here, and I need not say much more than that.
I did omit that infirmation, my bad.
He gives me the correct quality.
There are levels of purity and moisture content, as you pointed out.
It is a small indudtry here, medical chambers and such, and less than ten sellers, so a common item here, and I need not say much more than that.
I did omit that infirmation, my bad.
And what makes you make such a strange claim ? Crazed glue joint is reacting to the PO's OCD. Tinting will hide /obscure the apparently offensive joint.. neatly.
Small to no value in having a clear as glass view of some old TT when its' not in use
I repeat here:
'DCM will cause disintegration of the plastic, it has started, those big marks are characteristic.'
No point in painting a cracked wall, as an analogy, the material is disintegrating, will become small flakes over a period of time.
It is better to make another when the old one is intact, easier to take measurements and so on.
'DCM will cause disintegration of the plastic, it has started, those big marks are characteristic.'
No point in painting a cracked wall, as an analogy, the material is disintegrating, will become small flakes over a period of time.
It is better to make another when the old one is intact, easier to take measurements and so on.
One other thing, the vapour is heavier than air so there are risks posed by buildup in unexpected places even in a ventilated room.
I'd prefer to use it in a fume cupboard that vented directly outside, well away from passers by. Otherwise be careful.
To my amazement it's available retail in the UK. But only to approved, registered companies. They carry out Id checks too.
I think you are over reacting, the amount needed to solvent bond a turntable cover will be <10 cc or so, and most will be absorbed by the sheet.
Here, it gets stifling hot, so 1400 rpm fans with scimitar blades are used for ventilation.
In your location, yes, in winter, you need to be careful.
But for 2 cc, I do not consider it a hazard, if done only occasionally.
Fire risk is there, and read up, because we forgot some things after they became habit.
Here, it gets stifling hot, so 1400 rpm fans with scimitar blades are used for ventilation.
In your location, yes, in winter, you need to be careful.
But for 2 cc, I do not consider it a hazard, if done only occasionally.
Fire risk is there, and read up, because we forgot some things after they became habit.
I did chemistry at Uni (in the 70's). Even then they were paranoid about these things. If you broke a mercury thermometer they had a technician come round with a special vacuum cleaner to try and hoover up every last globule. Anything aromatic was used in a fume cupboard. We weren't even allowed near Benzene, though one of the professors thought that was OTT. He said he and his peers used to wash their hands with the stuff
One woman did come close to blowing up the lab by trying to wash out a large round bottom flask that was stuffed with sodium wire. Not content with cold water, she was about to use hot water but the lab technician got to her just before the tap went on... She left the course after that.
I'm just cautious with all that stuff, 'harmless' or otherwise.
Benzene is a listed carcinogen in the USA.
UK, fume cupboards.
Germany, benzinmotoren means spark ignition car, it was used as fuel there.
From Quentin, Top Gear, BBC.
So an American will go into shock if he / she sees it as car fuel, and a German will have a shocked reaction if told his car fuel will cause cancer.
Opinions vary, but if someone solvent bonds a cover once in many years, not a risk.
You can also use a transparent adhesive, of the kind used to bond handles to glass doors.
Then less of an issue...
UK, fume cupboards.
Germany, benzinmotoren means spark ignition car, it was used as fuel there.
From Quentin, Top Gear, BBC.
So an American will go into shock if he / she sees it as car fuel, and a German will have a shocked reaction if told his car fuel will cause cancer.
Opinions vary, but if someone solvent bonds a cover once in many years, not a risk.
You can also use a transparent adhesive, of the kind used to bond handles to glass doors.
Then less of an issue...
There was a sodium factory here, the workers used to throw marble sized bits into a pond, they would explode.
Rejects from medical grade sodium metal production...
And a microbiologist here smells the culture samples of sick patients, he can tell the species by the smell. I think that is dangerous, he does it all the time, no issues at all. PhD., after medical school, so he is well qualified.
So I still think you are being a bit over cautious about 2 cc of CHCl3...
Moderators, your call...
Rejects from medical grade sodium metal production...
And a microbiologist here smells the culture samples of sick patients, he can tell the species by the smell. I think that is dangerous, he does it all the time, no issues at all. PhD., after medical school, so he is well qualified.
So I still think you are being a bit over cautious about 2 cc of CHCl3...
Moderators, your call...
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UK/US/German and other countries' terminology is different. What you call benzene we call benzol (C6H6). What a German calls "das Benzin" is called gasoline or simply "gas" in the US but petrol in the UK. But we used to burn petroleum in kerosene lamps, and airplanes run on "kerozin" as jet fuel.
And criminals in thrillers use a rag soaked with chloroform to quickly make their victims asleep. It must be available off the counter.
Life is not simple.
And criminals in thrillers use a rag soaked with chloroform to quickly make their victims asleep. It must be available off the counter.
Life is not simple.