Just finished my first restore with great success!

I was mildly familiar with the celluloid material and got some good results from shaping it. In a day or two, my package from Masecraft should arrive and I'll start on a set of horn scales next. The question that I have is can someone tell me the difference in workability between the two materials? What things are the same, what's different, what type of pitfalls should I look out for?

I also might try my hand at doming my washers a bit for this next job and picked up a doming set from HF in preparation. With so many options, which one do you guys use for doming? Wouldn't a domed washer tend to dig into the scale material a bit?

Thanks!