I made MML the other week after years away. I'd forgotten how difficult I'd found it to melt the lithium grease using a soup warmer left over from our old restaurant. Essentially a double-boiler - on high, the water boils. Simply, it never even started melting. Pretty good fit between the insert and the warmer but perhaps there's too much heat loss. I really don't know.
I ended up putting the soup insert on a heat diffuser on the stove and even then it took significant heat output to get any action.
I kept it constantly stirring, getting into he sides and bottom-bend of the insert with a flexible silicone scraper constantly as in making custard, to avoid hotspots and localized burning. Eventually, it did melt, but there was significant smoking.
I should have chopped up the paraffin and microwax blocks. As it was, there, too, it seemed to take forever, again, seemed they needed a high heat (on the diffuser).
Finally, I took the insert of the heat for a few minutes and added in 3 lbs of yellow beeswax pastilles (I'd forgotten what they were called - granules). Solid block, returned and took off heat to get melting, with melt rate increasing as mass gave way.
My concern is that I basically fried the beeswax and rendered the lube unusable. I had no thermometer. Are there signs one has ruined the properties of the beeswax? It solidified into exactly what my memory serves as MML, at room temp.
I have a spare small microwave. Next time I think I'll just do it this way, on lower power.