Open time of types of urushi?
Hi Guys, Ive been doing some largish surfaces. Large boxes.
I began wondering how long urushi ( ki or kurome types) can sit out while working.
My work space is generally around 18c and 55% , Im in Hawaii and thats about as low as I can get it generally. I can drop the % a little to 50~52 but then Im running the dehu the entire time the ac is fighting down the heat from the dehu. its and epic battle and electricity is 60 cents per KW....
Using ki urushi, fuki application, The surfaces are about 1m square . So they take a it of time to cover. Then by the time I get to the end of the "coat", ( 5 sides) the first side has been sitting for a few hours or more before going into the muro. Its been going fine so far. Ive been trying to only put out enough for one side at a time to keep the the urushi fresh in the bowl. I have been wondering if the laccase would be getting tired sitting out for 5 hours.
My dry times are a bit slow. The muro is set for about 22.5c and 75%, Its about as cool as I can get it. Easier to control the H%. Still a little tack after 12~18 hours, set in about 30 hours, dry to recoat in about 60 hours. Id really like to get 1 coat per day. I actually dialed back the muro from 80+% because I thought I was getting surface curing.
My coats have been as thick as possible, meaning Im wiping off with paper for all the intermediate coats and not rubbing until the paper is clean. I rub until I can no longer see streaks from the rubbing.
Theres definately a point when the ki urushi has lost all its milk and looks like a dark kurome. The turps at this point has probably evaporated out as well. And it starts to thicken a bit after about an hour or so. It seems like it dries fine still. Ive been adding a bit of fresh to it sometimes to complete a side of the box if I did not put out enough initially. Then if there is remaining from batch 1 I just add more for batch 2 and mix together then filter to keep it clean. It seems a little darker, maybe it just thicker.
What are folk's thoughts on adding more turps as the original turps evaporates off?
Scattered post, non sequitur responses welcome.