Reassembling DA 50-200mm

Hello. Please, help! I have disassembled my DA 50-200 in order to remove dust and now I can't reassemble it. I guess there are some tricks related to the correct positioning of some parts. Does anyone can help me? Many thanks!

According to Haynes manuals reassembly is a reverse process of disassembly

Lenses are highly complex and it may well be that this one is now destined for a repair house to reassemble. I only tried this once, on a totally broken lens, and won't ever be trying it again.

Small amounts of dust in a lens won't affect performance.

threw 2 in the bin yesterday trying this trick, nothing important thank goodness

Erm - hands up all those who have not learned this lesson the hard way.

I destroyed a perfectly good Pentax FA 80-320 some years ago trying to cure 'the rattling noise' that I felt may be a screw that had become detached - although no issues in use. Wish I had put up with that rattling noise!

The bad news is - you are unlikely to be able to get it back together correctly - unless very lucky or skilful.

Best advice I can offer is put it down to experience - pick up a good used copy off ebay (they are very reasonably priced) and have your original one mounted and keep it as a reminder to yourself that dust does not matter

Carl