section1 Posted October 16, 2012 Report Share Posted October 16, 2012 Well this is my second post and I have another question. I applied shellac to my timber and then stained it, the stain that I have is an industrial spirit based fast drying and according to them it's dry in 15mins. I've discovered that isn't completely true so I let it dry for 24 hours before applying any lacquer. I usually spray it but this time I wanted to apply the fast drying poly semi gloss by hand rubbing it, as Marc did with the stool, I like the look of it. I mixed 50% poly and 50% methylated spirits, now you guys call that denatured alcohol but denatured containes part ethanol and part alcohol but our version contains alcohol yet they all claim it's the same and one thing so denatured and methylated are the same. To cut a long story short after applying this mixed portion onto the stained timber the stain stain was coming off the timber so much so that if I continued rubbing it I would of have gotten to bare timber. Maybe I've discovered a million dollar product but why has that happened. Has the shellac anything to do with it, is the stain a poor product or is the mixture just not designed to be put on stain. Quote Link to comment Share on other sites More sharing options...
section1 Posted October 16, 2012 Author Report Share Posted October 16, 2012 In addition to everything I have written the stain remains put if I apply Danish oil or the minwax antique oil finish, now that's what bugs me. Why does the stain come of using a polyurethane or lacquer based product and not so with the oil. I wonder if its because it's a spirit based stain. I'm off to experiement but if anyone has any ideas please let me know. Quote Link to comment Share on other sites More sharing options...
dcustoms Posted October 16, 2012 Report Share Posted October 16, 2012 I use the stains like you are talking about every day in my shop. I have never however rubbed a finish over the stain all my finishes are sprayed. With that being said Spirits or thinner will start to remove the stain after it is dry and denatured alcohol is like a universal thinner and would really take it off. Lacquer is made up of large amounts of thinner and is normally made to be sprayed on, not wiped on. Poly is also made up of a large amount of thinner(spirits i believe). When you are rubbing the finish on it is similar to taking thinner and trying to strip the stain. The other thing I just noticed in your post is that you applied shellac to the timber before the stain. It is entirely possible that the stain you are using did not stick to the shellac and is going to come off no matter what. In my experience when going over wood that is already shellacked I use gel stain or a similar product that is made to adhere and stain any surface. That would explain your results. Hope this helps, Dustin Quote Link to comment Share on other sites More sharing options...
HoboMonk Posted October 16, 2012 Report Share Posted October 16, 2012 Why would you use alcohol to dilute so-called "poly"? Quote Link to comment Share on other sites More sharing options...
Eric. Posted October 16, 2012 Report Share Posted October 16, 2012 Yeah, I see two problems right away... 1) I'm pretty sure poly is recommended to be thinned only with mineral spirits, and 2) If you use anything containing alcohol on top of shellac, the shellac is gonna come off. And if there's stain on top of the shellac, the stain is gonna come off with it. Try thinning the poly with mineral spirits instead of alcohol...I bet you have much better results. Quote Link to comment Share on other sites More sharing options...
section1 Posted October 16, 2012 Author Report Share Posted October 16, 2012 Thanks guys for your help it's tremendous, before reading this post I watched Marc's video again on finishing the stool and I realised then than I have mistaken mineral spirits with denatured alcohol. I watched so many episodes of different podcasts where they used denatured alcohol in creating shellac, that the word denatured got stuck in my head even though Marc clearly did say "mineral spirits" The unfortunate part even though we all speak English, different names for the same products are used. So mineral spirits we call mineral turps and denatured alcohol we call methylated spirits so that's where the confusion layed with me. The reason I used shellac was for the shellac to serve as a sealer so when I apply the stain it eliminates all the blotchiness and end grain darkening which it has, now you guys tell me that the stain will not stick over shellac and true enough it didn't even though I have thinned the shellac to probably a 1 pound cut or even less. Now the problem with shellac now is that I cannot find anywhere on our shelves dewaxed shellac, we do have zinseer products but they all contain wax. I bought shellac flakes orangebecause no other version is available the Feast Watson brand and I made it up myself but having asked them is this dewaxed they hadn't a clue as to what I was asking and the only reply I got was this is 100% natural. Just yesterday I received a Minwax pre stain wood conditioner which I'm now hoping will replace the shellac and allow the stain to dry Having said that I'm still faced with this new dilemna that I cannot wipe a finish over the stain other than using Danish Oil or the minwax antique oil which I imported from the U.S. none of the minwax products other than wipe on poly is available in Australia. I have read on the minwax forum that if you use a water base poly over an oil based stain that stain will rub off, but this stain that I'm using is called a craftsman dye fast drying stain which is spirits based and it's an industrial coating. It's touh dry within 5 mins and completely dry within 20 so they say. I still allow it to dry a full 24 hrs before spraying on the clear gloss. Even though I give it 24 hrs before spraying a gloss finish I did notice the stain ever so slightly shift, at first I thought the fumes were getting to me but now I realised that the stain was actually getting wet. It seems to me that I have no other option but to go back and spray the finishes which is not something I am looking forward too. Quote Link to comment Share on other sites More sharing options...
section1 Posted October 17, 2012 Author Report Share Posted October 17, 2012 Just a quick update this morning I applied the wood conditioner to a scrap of pineand then stained it, this time I allowed it to dry for only 30mins. I mixed up a small batch of fast drying poly and turps (mineral spirits) and applied it to the timber wiping very lightly. The first coat the timber absorbed it all it was touch dry within a minute of applying it. I'll give it 4hrs to dry and I'll apply a second coat, given the dusty environment we work in and not having the space and money to have a dedicated spray booth this is the only method of application I've got. Oh I did forget to mention that some of the stain did rub off on the rag but only a small portion due to the very light wipe, well fingers crossed I hope I achieve the result I'm looking for. On a last note I can't help but wonder by diluting this poly have I created a wipe on poly version. and if so how much am I really saving. Quote Link to comment Share on other sites More sharing options...
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