Mixing Shellacs

[NeilO]

Hi guys,

A question for the knowedgable...do any of you mix your own shellac finishes, I just watched Mark Spagnolio (sp?)WoodWhisperer on water like oil finishes and he promotes the use of shellac as a barrier between finishes saying its pretty much compatible with anything else ( oil , water, wax etc)

my questions are , other than if you mix your own ..

1. what is denatured alcohol?
2. once mixed does it keep, if so how long?
3. whats the difference between dewaxed and "normal" shellac ?
4.or is it just cheaper longterm to buy it ready made.(chestnut, Liberon etc)?

sorry a lot of questions but if I dont ask , I`ll never know :wink:

 

[Philly]

Neil
I mix my own shellac. Sounds posher than it is - you just mix the flakes with meths! (Yes, that's what denatured alcohol is)
Seems to keep for a long time (folks say it never sets as hard once it gets old but I've never noticed it)
The dewaxed flakes are just that - the wax is removed. normally this results in blonde shellac (the clearest in colour). I reckon it works out cheaper to make your own but if you've never used it try buying a small bottle to check it out.
Hope this helps
Philly

 

[NeilO]

Cheers for that Philly,

meths? you mean the purple stuff, or your going to tell me its available in other colours too :lol:

just want to extend my finishes, wax nice but no real protection,varnish run of the mill stuff, good protection to a degree, but always seems to be dull looking, and good old paint which is fine when its pine, but who wants to paint over some nice ABW or Tiger Maple...

 

[Philly]

Yup, the purple stuff! Some folks reckon they can see a trace of it in the applied finish but I've never experienced it.
Oh, and a coat of boiled linseed oil rubbed in before applying a few coats of shellac really brings out the figure in a lot of hardwoods (ABW especially!), if thats any help.
Cheers
Philly

 

[TheDudester]

Cheers for that Philly,

meths? you mean the purple stuff, or your going to tell me its available in other colours too :lol:

.... the stuff my grandfather used to put on his face everyday....
my grandmother said he never had a spot in his life :lol:

Regards

D

 

[bob_c]

I would use industrial meths if you can get it,also called IMS.Only usually available from chemical suppliers but its clear not purple and doesnt have half the nasties in it and smells just like vodka.The purple stuff gives me awful headaches and isnt too good for your health.Not many people know it but meths fumes are more hazardess to your health than acetone.

 

[NeilO]

Thanks fellas..

Bob c , I was looking at that but seems you have to have an HM customs license for it, I have found one place you can get it without license as such but you need approval from same HM customs to use it and can only have 20 litres per year...

think I will stick with the purple stuff , at least you can pick it up in the "sheds"

 

[bob_c]

I can get it for £7.28 for 2 1/2 litres.But im qualified chemist which helps.

 

[NeilO]

bob, thats interesting, I was looking at industrial suppliers sites, with a minimum delivery amount, and as I stated 20 litres is a minimum but you do need HM customs approval, go figure...
btw pricing was £12.99 for 5 litres minimum 20 litres and £8 del charge..

 

[tnimble]

Don't know the legislation in Britain. But in the Netherlands you have to need a licence to buy industrial meths (pure ethanol, instead of a mixture of ethanol, methanol (to render is poisonous) and a colouring agent) to avoid paying excise. Without the license you can buy it but pay alot to the state.

I use the purple coloured stuff mostly. Before using (I usually do a couple of bottles through in a batch) I filter the purple colouring agent out by putting some active charcoal in after a while I filter it thorugh a pain of coffee filter. Nice clean meths (although still not drinkable)

 

[NeilO]

handy tip tnimble, I must remember that one..cheers ( although not drinking the Meths :lol: )

 

[bob_c]

Its the methanol thats the nasty part ,it can destroy your retina and lead to permanent blindness .Some types also have an organic chemical called Pyridine in which is also nasty.

 

[jerryc]

Shellac is my favourite finish and I use it often. My advice is to mix your own, but only mix enough for the job in hand. Shellac flakes, properly stored will keep indefinitely. Problem with mixed shellac is that it starts a chemical reaction that overtime reduces the ability of shellac to resist water. I am convinced that shellac's undeserved reputation among some users, of shellacked finishes staining when exposed to water, stems from overaged mixed shellac. I have used it on the vertical surfaces of my kitchen where it has been subjected to the exhaust of the dishwasher--hot caustic steam- and it stood up to that for several years. I have also used it on two vanity units and the interior of a yacht.
I know the Americans talk of one pound cuts etc. but being a simple soul, I just cover the flakes with meth and that ratio is a good base mix. Adding more meth or more flakes as required can be done by eye.

Jerry


War does not decide who is right. War only decides who is left.

 

[bob_c]

For those who dont like breathing in solvent ,you can get water soluble shellac.

 

[tnimble]

Just finished a top with shellac. Its the top of my bench i'm going to replace in a few months. When my new bench is done this will 'degrade' to my assembly table.

Why shellac? Its the most fast, easy to apply, water resistant finish that can take a beating (very easy to repair)

Yesterday I filled a jar with about 2cm of orange/lemon shellac and filled it with mehts up to a total of about 6cm. Next morning routed a nice roundover and sanded the whole top. Cleaned up a bit and started applying the shellec with a pice of shirt. I dida total of 21 layers and finished with a layer of stairs grade water based varnish.

The only reason for the layer of varnish is that I play with mehts on my bench at times. To put on one layer of varnish with a brush (fairly wide brush) takes longer than about 4 layers of shellac and its still drying (about an hour has passed now) while with shellec its dust dry within a minute and fully hard in about an hour or two (depening on the number of layers). With mot varnishes and paints it takes about a few weeks upto a month to fully cure and reach final hardnes.

Also shellac does not colour overtime and can be put oer any surface.