make one not really hard to do iam in the proces of making one
saving for the 12inch x 12inch baader film from astronomy and telescopes ($55 Including postage)
I made a solar filter from a number 10 arc welding glass and my moon filter, it worked good enough to see the Venus transit, at least the start of it, the clouds came and spoiled the rest.
But to use just a welding filter, you would need a 15...or there abouts.
I cut a disc of cardboard, 4 inches larger than my telescope, cut multiple cuts 2 inches deep all around the edge,(to fold around the scope). And then cut an oblong hole just smaller than the filter, and stuck it on with tape.
Then I folded the cut edges around the scope and taped that on also, it worked great.
The filters are about 2 inches by 4 inches, but I had no problem with viewing.