Proxxon 38544 Longneck Angle Grinder LHW/E by Proxxon

Q: Is this variable speed.

Yes it is, but it also the first feature to fail, at least in my shop. I don't know why this otherwise good and useful tool should have a badly placed set of controls and fragile variable speed feature, but it does.

Q: What size is the grinding disc?

It uses 2inch discs same as the King Arthur's Merlin 2. The Proxxon seems less prone to over heating than the Merlin II.

Q: Mine burnt up after 18 months, now what? sol?? get another??

I have purchased too many of these. The same or similar experience as yours. These are for ultra-light use. To the point that, in my opinion, they are not useful. I will not buy another. I have tried to use them for smoothing hand carved bowls, small to medium. They overheat very quickly. Can only be used for a few minutes at a time. Way overpriced for their durability.