View Full Version : Canned Shellac confusion
Tegmark
11th December 2014, 07:03 PM
I'm using the Zinsser brand here.
Do you find sand paper gets clogged so easy & you go through a huge amount?
I still don't really know if this canned finish is designed for an off brush or spray finish to look anygood?
So far after 4-5 coats it doesn't look very glossy & reflective.
Or is this really for cutting & polish? Going from fine compound to finer with a pro buffer.
ubeaut
12th December 2014, 12:13 AM
Probably for French Polishing or brushing with a really good brush.
If you haven't used shellac before it might be a good idea to seek out some help with thinning and application. Most people use it straight from the can and end up in strife if they don't have a clue. It most likely needs to be thinned before use. Zinsser's is a USA product so you might also need to consider that it is may be coming from US and that it has a reasonably short shelf life when premixed.
I don't know if Zinsser mix theirs here in Australia even if they do it's a good idea to find out when it was mixed and what the useby date is (was).
It isn't like brushing on a coat of polyurethane or acrylic paint it needs a little bit of expertise, especially on a large surface.
We have a book called "A polishers Handbook (http://www.ubeaut.com.au/book.html)" which is designed to help out first time users of shellac.
There are a couple of copies left in captivity but once they're gone there won't be any more available until maybe mid Feb 2015. We are in the middle of a rewrite and the way I'm going it may not get to the printers until late January.
Hope this is of some help.
Cheers - Neil :U
PS Apologies for the blatant advert.
Goggomobile
12th December 2014, 07:33 AM
I just brought a copy of Neil's Polishers Handbook from Carrolls in Victoria.
I dont know Neil nor do I work for any suppliers .. I'm a shed toiler in sunny Qld.
I highly recommend a copy.
Why ? I'm a toiler, have young kids, busy job, busy life ... I've mucked around for years with all sorts of coatings and finishes. Plenty of blues and the odd success. I really never knew why some things worked and some didn't. The book clears up a lot of this confusion.
There is a great section on wet sanding and finishing with turning .... I would have never thought of this in a 100 years.
One of the other issues I always have is ... compatibility of coating .. Eg can I put a water based coating over a spirits based coating .. ... The book covers this really well.
Anyway get a copy and give it a go. :)
Randal ... PS I'm a Goggomobile owner with a wood working fetish !!!
ubeaut
12th December 2014, 11:38 PM
I'm a Goggomobile owner with a wood working fetish !!!
Are you sure you don't mean you have a Goggomobile fetish but love playing with wood. :U
Thanks for the nice comments on the book.
Cheers - Neil
_____________________________________
Tegmark - I spoke to a friend today (with whom I buy in my shellac) this gentleman is like the guru of shellac knowledge and he tells me that he's pretty sure Zinsser's main shellac product in Australia (to his knowledge) is used for sealing cement or something similar to give it a waterproof coating so it may be that the shellac you have is not the right product for what you want to do.
This is not gospel just a suggestion as neither of us really know. However, I would suggest talking to the Zinsser supplier to get a little more info about the product, it's use, and it's use by date. There's nothing better than getting the info first hand from the people who should know.
Hope this is of a little more help.
Cheers - Neil :U
RoyG
15th December 2014, 11:43 AM
I would suggest talking to the Zinsser supplier to get a little more info about the product, it's use, and it's use by date. There's nothing better than getting the info first hand from the people who should know.
Cheers - Neil :U
Thought this information might clear up the questions about Zinsser Shellac....
The following is a download link to the Technical Data Sheet for Zinsser Bulls Eye Shellac:
http://www.rustoleum.com.au/images/rustoleum/technical_data/tds/Zinsser/BE%20Shellac%20Amber%20TDS.pdf
Zinsser Bulls Eye Shellac is the same as other shellacs (ingredients; Shellac + Alcohol) except that it is sold pre-mixed with alcohol. It's available in Amber or Clear.
I was caught out as a result of buying out of date cans of Zinsser Shellac from a certain Big Green Coloured Shed. That is is why I originally sought out the above information from Zinsser about six months ago. When I tried to use one can of Zinsser Shellac, I found that it was taking ages to dry - basically it remained tacky, and wasn't tack free by the end of the day. According to the Technical Data Sheet, Zinsser Shellac has a shelf life of three years from manufacture. The manufacture date stamped on the bottom of my cans showed that all three cans were 2 yrs 11 months since manufacture. The age since manufacture, combined with the effects of being stored in a hot Australian warehouse for a few summers (note: Zinsser recommends storing below 95 degrees F), meant that the product had gone off. The Big Green Shed replaced my three cans of almost out of date stock with fresh stock that was five months since manufacture, and gave me an extra can as a way of saying sorry, and to cover my time required to clean off the shellac that wasn't drying.
Regarding the shelf life and storage conditions for Zinsser Shellac, the following is extracted from the product's Technical Data Sheet:
This product is formulated to maintain rapid dry time and maximum film hardness for 3 years after the manufacture date stamped on the container bottom. After that time check for proper drying by brushing on a piece of scrap wood. If the surface is not dry tack free within 2 hours, do not use. Higher storage temperatures may shorten shelf life. Do not expose to storage temperatures > 95ºF for extended periods of time.
Note: I have no affiliation with Zinsser products. I simply use it because Zinsser's pre-mixed shellac is cheaper and more convenient than other brands of dry shellac, and I can buy it from my local hardware store. Other brands of dry shellac may be better, but as part of my woodturning finishing, I use the finishes that I can get locally. It's sold as a 3 lb cut, so is easy to dilute to other cuts for whatever purpose you have in mind, and the Technical Data Sheet includes the dilution directions down to a 1 lb cut. Zinsser's USA web site mentions a Zinsser brand Alcohol for further diluting the product, but it doesn't seem to be available in Oz .... but I've been using Digger's Metho (Methylated Spirits - a.k.a Denatured Alcohol in the USA) with no problems.
I hope this info has been useful.
Regards,
Roy
old_picker
16th December 2014, 12:03 PM
if mixed shellac has been around too long the result is clogging of the paper
find some dewaxed blond flakes and make your own - freshly made shellac dries in very short order and sands off in a fine white dust - no clogging
suppliers to the confectionery trade are a good cost effective source for high quality shellac -
i bought a kilo in bayswater for i think $50 and 1 kg flakes makes a lot of shellac
tip some flakes in a large vegemite jar and fill with diggers metho until the flakes are covered
stir it every couple or 3 hours during the day and next day you can pour off the liquid and add an equal amount of diggers metho
thats your wiping shellac ready to go on the job
tip some meths on the residue and leave for another day - if you got good quality flakes that will break down as well and can be tipped into your mix
it doesnt last too long so make small batches and whatever is left over chuck out
i would not bother with the canned stuff especially if it is coming from OS
Tegmark
17th December 2014, 05:49 PM
if mixed shellac has been around too long the result is clogging of the paper
find some dewaxed blond flakes and make your own - freshly made shellac dries in very short order and sands off in a fine white dust - no clogging
suppliers to the confectionery trade are a good cost effective source for high quality shellac -
i bought a kilo in bayswater for i think $50 and 1 kg flakes makes a lot of shellac
tip some flakes in a large vegemite jar and fill with diggers metho until the flakes are covered
stir it every couple or 3 hours during the day and next day you can pour off the liquid and add an equal amount of diggers metho
thats your wiping shellac ready to go on the job
tip some meths on the residue and leave for another day - if you got good quality flakes that will break down as well and can be tipped into your mix
it doesnt last too long so make small batches and whatever is left over chuck out
i would not bother with the canned stuff especially if it is coming from OSThanks, ill consider this. This canned shellac was just so I could see what shellac looks like. Looks amber & clear, very different from PolyU. Glossy, but not as much as PolyU. Some times when sanding its a fine white dust, but most times its not. I have learned to use small varnish type disposable brushes (probably not possible on larger areas) as it just seems easier compared to cleaning the brush.
RoyG
17th December 2014, 07:02 PM
...... Some times when sanding its a fine white dust, but most times its not. .......
Check the manufactured date on the bottom of the can. According to Zinsser, up to three years is OK, provided that the can hasn't been stored in conditions over 95 F. If it is still fresh enough, it should dry hard and sand to a fine white dust within an hour or two, depending on the day, and depending on what dilution (called the 'cut') that you are using. If it's not dry enough to sand to produce a fine white powder after a few hours, then you probably need to chuck the shellac, although I'd probably let it dry overnight to see if it dries hard enough.
The contents of the Zinsser can are diluted to be a "3 Pound Cut" (i.e. 3 pounds of dry shellac mixed with 1 US Gallon of Metho). For finishing woodturning items on the lathe, I usually dilute the Zinsser Shellac with additional metho to dilute it to be a 1 Pound Cut (The Zinsser instructions include details of the amount of metho to add). I use a measuring cup and dilute accurately to get the cut I want. Other people I know just estimate (two glugs of this and one glug of that) when diluting their shellac. Whatever works for you. I find that the Zinsser Shellac takes longer to dry hard when you use it straight out of the can at the 3 pound cut - so maybe try diluting it to a 2 pound cut or even a one pound cut, depending on how you're applying the shellac, and what you're using it for.
If you're using the shellac on a valuable antique, or you're french polishing something that you expect to last a 100 years, or some other important project - then do yourself a favour and buy dry shellac flakes from a reputable supplier (e.g. Ubeaut), and mix small quantities of shellac as you need it. I say "reputable supplier on advise from a professional French Polisher who says that some of the shellac used in other industries (i.e. confectionery as an example) has apparently been 'refined' after being de-waxed. The extra refining can effect how the shellac behaves as a finish on wood. A local lady who does French Polishing for a living mixes her own shellac, and says that she throws out liquid shellac that is more than a month old, as by then it has reacted enough with the air to not produce the high quality French Polish finish she is after - but then she is very particular about her shellac.
I on the other hand, use shellac on woodturnings as a finish, and on furniture etc as a finish, and also as a sanding sealer under other finishes. I'm not that particular about how old my liquid shellac is, as long as it dries hard within a reasonable period of time, at most overnight. So, I use the pre-mixed Zinsser Shellac mainly for convenience; mostly because I can buy it locally as against having to order dry shellac on the internet and then wait for the post to arrive.
You also mentioned that you were having problems cleaning shellac brushes - the brushes should clean easily in metho. If you keep a set of brushes dedicated to shellac, you don't even need to dry the brushes - just clean the brushes in some metho, and then leave them standing in a jar in clean metho with a lid on the jar. When you use the brush next time, just dry most of the metho on the brush and go for it. When brushing shellac, I've had the most success using natural bristle brushes (not synthetic bristles) - I don't know why, but the natural bristles seem to let me lay down a nice finish more easily. Softer and finer bristles seem to help as well.
Hope that info is useful.
Roy
old_picker
17th December 2014, 07:11 PM
i am not that particular about getting it on
i use a piece of folded paper towel and lay down 4-6 coats then block it completely flat ready for lacquer
i use it mainly as a sanding sealer - it works great for that - for my guitars it is not a robust enough finish - it dissolves in alcohol - definitely no good for your average scotch swilling picker
Tegmark
18th December 2014, 07:05 PM
Check the manufactured date on the bottom of the can. According to Zinsser, up to three years is OK, provided that the can hasn't been stored in conditions over 95 F. If it is still fresh enough, it should dry hard and sand to a fine white dust within an hour or two, depending on the day, and depending on what dilution (called the 'cut') that you are using. If it's not dry enough to sand to produce a fine white powder after a few hours, then you probably need to chuck the shellac, although I'd probably let it dry overnight to see if it dries hard enough.
The contents of the Zinsser can are diluted to be a "3 Pound Cut" (i.e. 3 pounds of dry shellac mixed with 1 US Gallon of Metho). For finishing woodturning items on the lathe, I usually dilute the Zinsser Shellac with additional metho to dilute it to be a 1 Pound Cut (The Zinsser instructions include details of the amount of metho to add). I use a measuring cup and dilute accurately to get the cut I want. Other people I know just estimate (two glugs of this and one glug of that) when diluting their shellac. Whatever works for you. I find that the Zinsser Shellac takes longer to dry hard when you use it straight out of the can at the 3 pound cut - so maybe try diluting it to a 2 pound cut or even a one pound cut, depending on how you're applying the shellac, and what you're using it for.
If you're using the shellac on a valuable antique, or you're french polishing something that you expect to last a 100 years, or some other important project - then do yourself a favour and buy dry shellac flakes from a reputable supplier (e.g. Ubeaut), and mix small quantities of shellac as you need it. I say "reputable supplier on advise from a professional French Polisher who says that some of the shellac used in other industries (i.e. confectionery as an example) has apparently been 'refined' after being de-waxed. The extra refining can effect how the shellac behaves as a finish on wood. A local lady who does French Polishing for a living mixes her own shellac, and says that she throws out liquid shellac that is more than a month old, as by then it has reacted enough with the air to not produce the high quality French Polish finish she is after - but then she is very particular about her shellac.
I on the other hand, use shellac on woodturnings as a finish, and on furniture etc as a finish, and also as a sanding sealer under other finishes. I'm not that particular about how old my liquid shellac is, as long as it dries hard within a reasonable period of time, at most overnight. So, I use the pre-mixed Zinsser Shellac mainly for convenience; mostly because I can buy it locally as against having to order dry shellac on the internet and then wait for the post to arrive.
You also mentioned that you were having problems cleaning shellac brushes - the brushes should clean easily in metho. If you keep a set of brushes dedicated to shellac, you don't even need to dry the brushes - just clean the brushes in some metho, and then leave them standing in a jar in clean metho with a lid on the jar. When you use the brush next time, just dry most of the metho on the brush and go for it. When brushing shellac, I've had the most success using natural bristle brushes (not synthetic bristles) - I don't know why, but the natural bristles seem to let me lay down a nice finish more easily. Softer and finer bristles seem to help as well.
Hope that info is useful.
Roy
Big thanks, Now makes sense since I was using Turps, & wondering why it did nothing cleaning it. This can is just for a testpeice I plan to cut & see if I like it. If I liked it, I would now doubt use flakes. Still not sure if this shellac finish is able to come into contact with water like when being dusted or cleaned off like on a desk? That's one thing I love about PolyU, it can take anything, windex, iso alchol etc for cleaning.
Hermit
18th December 2014, 07:09 PM
That's one thing I love about PolyU, it can take anything, windex, iso alchol etc for cleaning.
Not acetone though. :no: