# Helmsman Spar Urethane.... When does the STANK go away?!



## ubermick (Feb 5, 2013)

Jebus. So I finished my first "ambitious" project, an astronomy eyepiece case. I based the design off a commercial wooden case, and since they use Helmsman Spar Urethane to finish their cases, I followed their lead and used it on mine.

While I'm certainly not a fan of the stuff now (hindsight being 20/20), I'm now somewhat married to it since the inside and outside was finished with it, and there's no getting it off. The last coat was applied Saturday, and on Sunday I moved the case outside to air out (we've been getting unseasonably warm weather of late, so it's been clear with temps in the mid 60s/low 70s all week) and moving it back inside at sundown. Five days of that, though, and the finish still absolutely reeks.

Since this case will hold pushing $1,000 worth of sensitive coated optics, it's unusable as long as this is going on. So anyone got any advice to speed up the destankification process? Is this something that needs patience, or am I potentially screwed?


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## Loren (May 30, 2008)

It may take a month or so to cure, but it will. Spar
varnish cures by oxidation, not by drying, so make
sure air circulates. Cabinets finished inside with
varnishes can take months to cure inside if there
is a closed door inhibiting air flow.


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## wapakfred (Jul 29, 2011)

I would be willing to bet the inside of that case is going to smell for a really long time. Like Loren said, it takes reacting with the air….if that will be unacceptable, I'd say you may be potentially screwed. When ever you finish an interior surface and you don't want an odor problem, try using shellac, lacquer, or a waterborne finish.


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## ubermick (Feb 5, 2013)

Crap on a cracker, that's what I was suspecting. But yeah, since I lined the bottom and lid of the case with velvet, I can't just strip it off and refinish. Looks like this thing is going to be staying outside for a few more weeks…


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## JoeinGa (Nov 26, 2012)

Maybe you could find some of that "stuff" that absorbs odors … Kinda like the stuff that sucks up moisture. If you could buy that stuff in say a quart or 1/2 gallon size you might could close it up in the case and let it do it's thing?


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## JoeinGa (Nov 26, 2012)

ORRrrrrr, how many of those Dr Scholl's ODER EATERS for shoes would it take ?


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## BillWhite (Jul 23, 2007)

Dry vs: cure. Herein lies the quandry.
You'll just have to wait it out.
Bill


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## ubermick (Feb 5, 2013)

Yep, looks like that's the only option. It's downstairs with a fan blowing on it, and a dehumidifier in the room (not that this will do any good for oil, it's just there in general), and hopefully it'll get sorted.


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## SCOTSMAN (Aug 1, 2008)

The stenkee hum will go sooner rather than later open it up to the elements and let the air circulate and it will be a good stout strong finish in the end.Alistair


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## ClintSearl (Dec 8, 2011)

I feel your pain, but it's a great argument for limiting the use of spar varnish to spars, unless the box is gonna be lashed to the yardarm. Nyuk Nyuk


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## ubermick (Feb 5, 2013)

Yarrr, it no be exposed to the harsh elements, mateys. But yep, hindsight being what it is, I'll never use this

```
#$#
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 again. Two weeks now, with one week of it opened up completely in front of a fan running 24/7, and opening the case if it's been closed for 15 minutes smells like opening a fresh can o' urethane. Staaaaaanky.


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## verdesardog (Apr 2, 2011)

Use spar varnish for outside pieces only… guess you learned a valuable lesson


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## Tennessee (Jul 8, 2011)

I have a small curing oven heated by light bulbs. It holds one guitar body or about three small projects. It has an air flow passive vent system and with about two days with the oven at the usual 92' temp, urethane stank goes away. For you, maybe direct sunlight with a small fan?


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## gfadvm (Jan 13, 2011)

I'll bet a coat of shellac on the inside of that caser will stop the smell instantly!


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## Bocum (Jul 15, 2020)

Hi Ubermick, I know it's been over 7 years, but has the smell ever gone away ? Reason I am asking is that I used this product for the entire basement at my cottage, and the smell is just horrific.


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## Unknowncraftsman (Jun 23, 2013)

Why would you use a oil based product indoors. Start scraping wear a P100 mask. With a organic vapor cartridge 
Even the water based stuff isn't that great indoor on a large scale but at least it will dry in a your lifetime.
Good Luck


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## Bocum (Jul 15, 2020)

Well, here is the specific problem I tried to address - small walkout basement (500 sqft) at the cottage in north Ontario that i rebuilt using plywood sheets on walls and ceiling. Humidity levels in the summer are very high, thus frequent mold problems, therefore I wanted to protect the plywood with something strong. The ventilation is poor, I have to add. It sounds like I may have to take all that plywood out and install new one. What would you suggest to use if I was to start from scratch ?


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## John Smith_inFL (Dec 15, 2017)

another new member posted here after he varnished the inside 
of his newly made sauna with Helmsman Spar and it is totally unusable.
as far as I know, he never came back with a resolution of the problem.

the list of reasons NOT to use Helmsman Spar is growing, and growing, and growing.

.


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## AlaskaGuy (Jan 29, 2012)

Old thread but maybe it will save somebody

Even if it doesn't stink Helmsman Spar has a bad reputation among the pros.

https://www.woodweb.com/forum_fdse_files/finishing/794926.html


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## wapakfred (Jul 29, 2011)

Helmsman stinks for a large variety of reasons…and most of them aren't even related to the smell.


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## ibewjon (Oct 2, 2010)

I used oil base varathane on all my floors, no problems. Maybe a week, all smell gone. I never use water base because it does nothing for looks. I want the look of oil base.


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