If I apply poly in cold weather, say around forty degrees, will it just take longer to dry, or will there be other problems? How about shellac? Thanks.
Discussion Forum
Get It All!
UNLIMITED Membership is like taking a master class in woodworking for less than $10 a month.
Start Your Free TrialCategories
Discussion Forum
Digital Plans Library
Member exclusive! – Plans for everyone – from beginners to experts – right at your fingertips.
Highlights
-
Shape Your Skills
when you sign up for our emails
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. -
Shop Talk Live Podcast -
Our favorite articles and videos -
E-Learning Courses from Fine Woodworking
-
-
Replies
I was wondering the same thing. In fact I applied a stain two days ago that still hasn't dried enough for a top coat. It's been humid and rainy.. but the low temps are only in the 50's. Can only imagine how long it will take the poly to dry between coats.
bill
The rule is no finishing if the temperature of the wood, finish or environment is below 60 degrees. Below that, the chemical reaction that allows the finish to cure is inhibited. Check with the manufacturer of the finish for details. The drying time called out in the instructions is almost always based on 70 degrees and no more than 75% RH.
Build a tent from a tarp or plastic an put an electric radiate heater underneath. Be careful to keep the tent away from the heater and don't let the temperature get above about 85 degrees.
Okay, let's say you didn't know about the "no finishing under 60 degrees" rule and did it anyway, as I just did this weekend, will the stain eventually dry? Thankfully I haven't top coated yet. Thanks.
bill
Edited 11/5/2002 5:01:20 PM ET by bill
Bill,
The best thing to do is get the piece into a warm, dry environemnt immediately and wait a few days. It will probably be OK. Stain isn't that finicky. The worst you may need to do is a light sanding with your final grit and re-staining. But there probably will be no need to resort to even that.
R
Rich.. I'm working in my garage and have fans blowing across the work. Are the fans a mistake? Also, perhaps I should use a space heater to bring the temp up, eh? And as for the poly top coat.. either wait for warmer, dryer weather.. or keep the garage door closed and the heater on while I topcoat? Thanks..
bill
Bill,
Fans blowing across the work. When? Finish wet - bad - lotsa dust. Finish dry to touch - no prob.
When finishing wood, the "finishing room" needs to be warm and dry. However you accomplish that goal. Warm and dry. Warm and dry. Warm and dry. Warm and dry.
"Yer pays yer money, and yer takes yer chances."
R
Got it. Warm and dry. Thanks.
P.S. I'm in trouble
Rich.. is there any way to get dust and other stuff you can feel (that wasn't there before I stained) off the stained finish before I topcoat? The Minwax stain can says, "do not sand between coats." Thanks,
bill
Bill,
If you can feel it, you sure will see it in the final finish. It sounds like dust settled on the wet surface and is now trapped there. Minwax advises not to sand the stained surface, anticipating that the stained surface is as dust-free after staining as it should have been prior to staining. That is - ready for finish.
It sounds like you NEED to sand off the dust nibs, get the surface realy clean this time, and finish in an area that is appropriately dust-free for finishing. There is no way around this need. We all face it.
R
Thanks, Rich. I'll use a 600 wet/dry first, followed by 0000 steel wool, hoping that not too much of the stain comes off. It could actually use a bit of lightening up.. it's a red mahogany that looks very dark.
bill
Bill,
I would not use steel wool on the surface after 600 grit. You will essentially be on raw wood at that point and steel wool on wood ain't the best idea. Also, you'll have to decide if you like the "lightening" effect of the sanding. You will be removing surface stain, while leaving stain in pores and other lower spots. It may look splotchy. Not like using a lighter colored stain on fresh, unstained wood. The sanded parts of the wood may look bare and may need a reapplication of (lighter) stain.
Good luck.
Thanks, Rich, for the advice. I'm never doing ANYthing again until I ask here first. Now.. what should I do to remove those surface imperfections before the topcoat? You said remove them.. but you didn't say how, so I was just taking a WAG.
bill
As Dick said, just get it warmed up and you should be OK. Take it to another warmer room. Oil based stain isn't as finicky in regards to temperature.
Howie.. yeah, I went to HD last night and bought a small, fan forced heater and overnight things are much better. Once the stain dries completely I'm going to apply my poly topcoat in my now warm garage. Thanks to you.. and Rich.
bill
Here's a link to a thread from about a week ago, asking the very same question re: shellac and cold. Some good information:
http://forums.taunton.com/tp-knots/messages/?msg=8661.2
David
Look, I made a hat -- Where there never was a hat!
That thread seams to be about a "chair".
Dave,
I don't think that anyone can give you an absolute answer on this about the effects of cold on specific finishes.
However, I'll think that you will get a near-universal consensus that you just should not finish wood if you can't get your environment up to about 68 - 70 F. Just don't do it. The finishing step FINISHES the job. It has to be right. There's nothing about that step that should be iffy.
You will experience problems varying simply from long cure times to changes in the nature of the drying/hardening/polymerization/whatever to the point of permanent unacceptability of the finish coat(s).
R
Oops... this should work:
http://forums.taunton.com/tp-knots/messages?msg=8575.1
(I don't know how "the chair" thread showed up... I didn't even read it!)
DavidLook, I made a hat -- Where there never was a hat!
This forum post is now archived. Commenting has been disabled