Hot Mop.

Apart from the obvious, (hard to work with, wasteful, etc) what are the detriments of hot mopping with Type IV asphalt that is below reccomended temp? Is it bad for the roof? Are you supplying an inferior product?>>>

If it's not equiviscous then by definition it will not spread well or penetrate the perforations well. Too thick makes a lumpety bumpety finished product and an unstable membrane. A too high goo to ply ratio is a bad thing in all walks of life. Things start sliding around later. (imho)>>>

You know the world is turning upside down when we have roofers that know the definitions of words like occlude and equiviscous and Presidents that struggle to know the definitions of words like tax and is.>>>

it,s just fun to yell HOT....>>>

I love the smell of pre-flashed pitch in the morning...... fact is.....asphalt that is mopped when not hot enough is hard work, and applies very thick, and asphalt that is too hot.... well, you'll be spending more time hoping that there's no fire. 400 degree asphalt is perfect for mopping between felts for adequate felt/ asphalt combination. too cold.....too thick...too hot, too thin.... simple as that......test cut forensics can determine asphalt temperatures based on thickness between plies.

>>>

welp, 400 is a tad too cold for me. You would have to be on a straight go and constantly replacing it with fresh hot to come out well at 400 degrees. 450 minimum imo. This is for hand-mopping; I know nothing about temps on machines. If you pump hot out of the kettle at 400, you cannot put the mop down for anything or the next time you pull it out of the cart you have glop. Once it sits at 400 it seems to crave the three hundreds. Anything in the threes, even the high threes, does not fly unless you are mopping insul down; gotta have sludge for that biz. Or maybe graveling something in.>>>

Hey Jeff, "... before it was hot enough to pump (carried it up the ladder one bucket at a time..."

You can pull out hot that is plenty hot from the center before the pump is thawed out enough to pump. Everything in your bucket could very well be at EVT and more before the kettle is. A bit dangerous extracting it though.>>>

The minimum temp is around 300.Plies won't stick goodtogether.The asphalt will be too thick and will crack and aligorate faster down the road.>>>

EVT is 525. Flashpoint around 550. We got ranges here down to 300?? Mopping at less than 5 would set me on the kettle mans ass as it is....>>>

Duplicate post.>>>

Having a proper evt is just one part of the equation for a successful application. Have you ever had to deal w/ "Summer" felts, when the manufacturers applies talc to the felts to keep them from sticking. Happened to us years ago when using Phillip Carey materials, and the hot stuff just floats negating any adherence between the plies. Their tech people came out to the job, to check and report the problem. Here it is 47 years later and still haven t heard - glad I didn t hold my breath.>>>

Back in the days we kept the kettle hot at around 560-580.By the time the asphalt was pumped and ready to be applied the temp would drop to around 500.>>>

http://www.owenscorning.com/trumbull/resources/downloads/temp_and_viscosity.pdf

"... In most instances, specimens prepared at application temperature at or above the EVT produced the more uniform interply mopping weights when compared to the specimens prepared at lower application temperatures. Machine application at temperatures below the EVT becomes irratic and difficult."

>>>

I neglected to state that virtually all my experience has been with Type3 asphalt. (That article is pretty interesting in its own right. A lot of people have put a lot of effort into this industry. Almost exhausting just to contemplate how much effort.)>>>

Well that's odd :huh: Yesterday I posted that I had printed out the info and made binders for the shop, thanking egg for the info..... and it has dissapeared. yeah I noticed most of the tests pertain to type III also but the comparisons should be close enough.

500F in the bucket and I'll mop for you all year. Problem I find is that most kettlemen dont know what it looks or smells like when it's reaching EVT and the small range before kaboom.