Help me assemble my eyepieces!

[rohitroxkp7]

I have a Celestron travel scope 70 telescope and two eyepieces of 10mm and 20 mm each. I disassembled them to clean the lenses, following which I forgot the order in which I had removed them.

Please help me put it back :'(

[jambouk]

Oh dear.

We have a tendency to fiddle with things when there is no need. I am more guilty of this than most.* You seldom need to take anything apart in astronomy to clean it.

Show us a picture of what you have and label them in a way that someone can give you meaningful instructions on how to reassemble it all.

James

* I really should have been a surgeon.

[Louis D]

Here is a diagram of common, simple eyepiece types.

Most likely, it's either a Kellner or Plossl-like.  The diagram shows the eye lens on the right and the field lens facing the telescope on the left.  A good rule of thumb is that convex surfaces generally face inward.  If you look at the edge of each lens, you should be able to tell if it is a singlet or doublet pretty easily by the presence or absence of a line.  If it is Plossl-like, it's probably a symmetric achromatic pair (like the lower left corner one) so it doesn't matter which doublet goes where, only that the curved surfaces face each other.  There will probably also be a spacer ring between the lens groups.

One tip to ease reassembly is to lower the barrel over the stacked lenses because they can tip and jam if you drop them into the upturned barrel.