These are good tips for successfully packing refractors. I'd like to add a few details.
1. Make sure the inside of the refractor is well stuffed with foam or crimpled newspaper. This allows better reinforcement for the glass so an impact won't blow it in if there's open air space inside.
2. There must be a minimum of 3-4 inches from the glass to the outer surface of the box.
3. Except for inside the refractor, never use newspaper for packaging! It's a very poor cushion since newspaper can cause object to settle near the bottom of the box, and also newspaper can get hard when it settles like that.
4. Of course don't forget to write Fragile and This End Up on all sides of box in red LOL.
Hope this helps. All of the above allowed me to ship 4 Form 109 globes and 2 Form 175 refractors with great success. Form 109 globes are incredibly fragile and anything less than that could result in a nasty surprise.
Dave, the Silverliner, can make good packing suggestions.....
I've also packed glass so well that it arrived intact. The secret is this:
1:Wrap the refractor in bubble wrap
2:Make sort of a "suspension system" out of styrofoam pieces or cardboard so the refractor can "float"
3:Packing Peanuts-Lots of it.
Make sure the refractor cannot move around in the box.