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Can anybody tell me what the safe extremes are for temperature and humidity when spraying KTM9? I'm just completing my first SS which means I'll be spraying the finish (vs. FP) and am wondering how warm it needs to be. My spray booth is my garage with the doors open, and now that winter is nearly here, I'm wondering how warm it needs to be to spray. Also, after spraying the guitar, since KTM9 is waterbased, is it safe to bring in the basement to dry? Any other pointers about spraying KTM9 would be greatly appreciated. And yes, I know there are some great finishers here who could do the job, but I'd really like to get good at doing it myself.

Thanks!

John

I believe that can states 65F and I don't recall a mention of the RH but would assume no higher than 60%. I spray all year long, but I have a small electric Oil heater in my spray room, keeps it about 72F in the coldest conditions I run into and I have had no issues other than the cure time being extended.

As far as tips are concerned, I basically follow the Doolin schedule. Except I pore fill with Zpoxy and seal with shellac and in cooler weather make my build up slower.

Best tip I can give is I have best results by keeping my coats light and during the winter no more than 2 a day.

In the summer I can rub out in 7-10 days but in the winter I give 3 weeks or longer if damp or unusually cold.

If this is your first sprayed finish this is the wrong time of the year to attempt it if you do not have a heated spray booth and good air supply dryer. Lots of things change about the way liquids atomise when the temps are low as well as the curability of the media.

John I forget where you live but in a cold area I would wait for warm weather if you can

Yeah , I was kinda afaid of that. I'm in Indiana and my garage is nomally aound 50 degrees (humidity <30), but that oil heater idea might be enough. I don't sell any of my guitars so I might give it a go just to see what happens. Maybe I'll spray a few coats on a scrap side set and see how it goes.

I should probably take your advice and wait until sping. This is my first SS build so I really want to string it up and see how it sounds. Maybe I'll glue the bridge on so I can play it awhile and spray it in the spring. Heck, if I can FP a classical I should be able to buff out the finish of a SS with the bridge already on. Are there any other things to look out for if I attach the bridge before spraying?

Thanks fo the advice!

John