I couldn't justify spending money on a solar filter which would hardly ever get used so I decided to have a go at making one. I purchased a cheap empty filter frame on eBay and some solar filter sheet on Amazon. The problem I had was the solar filter sheet is extremely thin and the retaining ring of the filter frame would not tighten down enough to grip the solar filter sheet. I therefore had to cut a ring from thin card to take up the slack... anyway it work great.