Hello Folks,
Seems to be a lot of topic drift here! As it happens, I have several 5 litre plastic containers full of BDH (that dates it, they merged with Merk twenty or thirty years ago!). It is a liquid with somewhat higher viscosity than water, so unless it is mixed with lots of solid powder it will run straight off the job. I am very dubious that such a witches brew will be anything like Trimite to sand down.
Equally all the two part body filler I have ever used is much harder work with than Trinite. The guy at Myford even let me try sanding the filled casting and it was quite amazing how easy it was to take off large quantities of material with very little effort. Filler putty is not good, you must put multiple thin layers onto the areas to be treated and wait for ever between coats,, otherwise it will never set below the surface. Even then it will shrink long term.
Sounds as though I am being finicky about this filling job. To get a good surface takes a fair amount of work and choosing the wrong filler, is not a good idea. I don't want to start all over again!
When I say that Myford's used a lot of filler, I mean that it was spread liberally all over the casting NOT just in the holes! My guess is that the surface of an ML lathe is ALL filler to maybe a depth of several millimetres!
Andrew.