Or at least I assume so. I've managed to strip the threads on 2 separate sets of cranks.
Screw the pedals all the way in (not cross threaded) with fingers, nip up nicely with spanner, hit a few drops and hey presto, the pedal is on a wonk and your brand new cranks have a dead thread.

How am I managing this? Is there any sort of a fix for stripped threads 'cos I cant afford any new cranks. At all.

Never had that happened to me in 17 years of biking – piccy/ crank type/ peddal type?

ive done it twice, both occasions cause by the pedal not being nipped up.

crap crank?
are you a bit of a more robust gent, and landing heavily?

could look at a crank with a steel insert in the pedal threads?

you can fix it, but it involves a helicoil (20 quid ish?) and its debatbale whether they are not as strong as the original thread (im sure someone suggested they may be stonger?)

Is there any sort of a fix for stripped threads 'cos I cant afford any new cranks. At all.

You might be able to get an engineering company to Helicoil them but will cost you as much as some second hand cranks off Ebay i would have thought

I had it happen once from overtightening the pedals.

My advice is to buy ones with steel inserts which do at least last much longer.

could it be the worn or poor quality thread on the pedals themselves? I have a crankset that will only accept my V12's due to similar threading issues.

Pedal axles bent?

What kind of cranks are they? I've had problems with XT cranks – the pedal thread seems to be an insert in the (hollow) crank arm, and it's possible to break them loose (did one set after 1.5 weeks riding in Whistler, the other after catching a pedal at 25+mph on the Mega).

I now use SLX cranks (double and bash version) which have a steel insert on my beefy bikes.