Removing sticky goo from exterior of old Sigma lenses - help

I took a chance and bought - sight unseen, yes I know - an old 35mm camera complete with three lenses and a not too shabby kit bag.
On a budget, any one of the lenses would have cost what I paid for the lot so, I thought, well worth the punt.
The glass on all three is bright and clear and has cleaned up a treat in seconds but, and it's a bit of a monster of a BUT, in varying degrees all three have very sticky, goo like exteriors, nasty to touch and leaves your finger tips tacky and blackened. One is now completely unusable following efforts to clean it.
A gentle rub with cotton buds has proven that nail varnish remover (NOT my idea), light fluid and a can of something which claims to remove chewing gum, grease, glue, your skin, hair and teeth have all failed - actually, maybe it does as I've no hair, recently lost a toe nail and the teeth aren't too good either so there's some doubt as to whether or not that stuff works in that way or not. I've tried the local chemists for IPA and got snarled at with a "What?" and even after translation got sent off brusquely to try the hardware shop who had never heard of it or contact cleaner either.....hmm.
Anyway, my wife, armed with a tea towel and her nail varnish remover has, so far, potentially wrecked the one I actually did want (Sigma 75-210), leaving it stuck on full extension and with most of it's legends wiped away. I daren't close it back down for fear of the goo getting where it shouldn't.
So, before I buy IPA online or just toss the lot, anyone have a clue what might work?
Thanks for any help.
On a budget, any one of the lenses would have cost what I paid for the lot so, I thought, well worth the punt.
The glass on all three is bright and clear and has cleaned up a treat in seconds but, and it's a bit of a monster of a BUT, in varying degrees all three have very sticky, goo like exteriors, nasty to touch and leaves your finger tips tacky and blackened. One is now completely unusable following efforts to clean it.
A gentle rub with cotton buds has proven that nail varnish remover (NOT my idea), light fluid and a can of something which claims to remove chewing gum, grease, glue, your skin, hair and teeth have all failed - actually, maybe it does as I've no hair, recently lost a toe nail and the teeth aren't too good either so there's some doubt as to whether or not that stuff works in that way or not. I've tried the local chemists for IPA and got snarled at with a "What?" and even after translation got sent off brusquely to try the hardware shop who had never heard of it or contact cleaner either.....hmm.
Anyway, my wife, armed with a tea towel and her nail varnish remover has, so far, potentially wrecked the one I actually did want (Sigma 75-210), leaving it stuck on full extension and with most of it's legends wiped away. I daren't close it back down for fear of the goo getting where it shouldn't.
So, before I buy IPA online or just toss the lot, anyone have a clue what might work?
Thanks for any help.

I had a similar problem with old film EOS550 camera exterior. Methylated spirit did the job. You put a dab of it on a cloth and change the spot on the camera/lens and cloth frequently. Now it's just hard smooth plastic - pleasure to touch. Unfortunately, the lens with nail polish in it is most likely a write-off, sorry for the brutal truth.

I assume that the goo is the old rubber from the zoom/focus rings breaking down.
If that is the case then nothing you use will work long term.
Try removing them from the 'ruined' lens and cleaning the barrel with your meths/IPA. If that works then get some of the light seal rubber for old film cameras (it comes in sheets you cut to size and ir readily available of fleabay) and use that to replace the old rubber.
If that is the case then nothing you use will work long term.
Try removing them from the 'ruined' lens and cleaning the barrel with your meths/IPA. If that works then get some of the light seal rubber for old film cameras (it comes in sheets you cut to size and ir readily available of fleabay) and use that to replace the old rubber.

Again, many thanks for the suggestions. Despite my best efforts and a few protestations, we didn't go anywhere near a likely source for either IPA or meths, unbelievable! Maybe, with luck and a following wind - rain tomorrow - I can manage a sideways shift over the coming weekend. Not too certain about stripping the things to replace rubber rings, I can barely see to type this! I'll let you know. Respect, Tony

The problem is that the rubberised coating is breaking down and there is really not a lot you can do to stop it. Using a sprit of some kind will only improve it but will not cure it. I have this on a pair of good binoculars and its also happening on my Microsoft Video Cam, I have tried almost everything but in the end it still comes back.........

Bleh! Waste of money then, poo
Still, the camera bag is much better than the old one and I might be able to salvage the least gooey of the three. Shame, the cost of a good condition 70-210 is more than I've already laid out (sigh) another one of those "lessons" learned they're always banging on about. Back to the 'bay and I'll steer clear of the other source from now on. Now to give the piggy bank another shake, sure I heard something rattle in it the other day.
Thanks all - although I still haven't gotten hold of any IPA, if it's cheap enough I might yet give it a try. See what despair..ation can do?

Still, the camera bag is much better than the old one and I might be able to salvage the least gooey of the three. Shame, the cost of a good condition 70-210 is more than I've already laid out (sigh) another one of those "lessons" learned they're always banging on about. Back to the 'bay and I'll steer clear of the other source from now on. Now to give the piggy bank another shake, sure I heard something rattle in it the other day.
Thanks all - although I still haven't gotten hold of any IPA, if it's cheap enough I might yet give it a try. See what despair..ation can do?

White spirit might work. We have some Kef speakers and the top had a rubberised coating, which over the years had gone sticky & looked horrible. After looking on various forums, someone suggested white spirit, so we tried that, the rubber coating came right off, leaving a lovely shiny painted metal surface.

I had to order Iso wotsit alcohol online in the end and it arrived this morning. A quick wipe with a micro cloth proves this to be THE STUFF and the 70-210 is now almost entirely gunge free. It'll need further, more delicate work, but it can be saved. So that's good. The other two are only minor problems and should clean up just fine.
kaybee was also correct, the focus rings on this first lens are breaking down - or at least one of them is. No time now, but I'll try and see if I can find a strip down guide for it, nothing obvious on the body itself with a quick peruse.
Many, many thanks for the answers, and yes, I've promised myself to be content with what I have and to stop looking at "bargains". Although there is a pristine Minolta going for just £50........
kaybee was also correct, the focus rings on this first lens are breaking down - or at least one of them is. No time now, but I'll try and see if I can find a strip down guide for it, nothing obvious on the body itself with a quick peruse.
Many, many thanks for the answers, and yes, I've promised myself to be content with what I have and to stop looking at "bargains". Although there is a pristine Minolta going for just £50........
