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tyabb wonder
4th October 2005, 01:23 AM
Hi all

Was wondering at what stage should I apply shellac as a sealer? Should it be done after I have sanded through the grades, will it require further sanding before applying the finish?

Also, if I was to use a poly finish or a poly/oil finish do I need a sealer and if so would shellac be suitable?

Cheers guys any help appreciated.
John.

Cliff Rogers
4th October 2005, 01:48 AM
It really does depend on what you like...

Try it out on a few test pieces.

I do mostly turning work & I've tried sanding sealer & I don't much go for the result.

I've used several different finishes & so far, I don't much like sanding sealer "." (fullstop)

Disclaimer: Cliff likes {insert feminine noun here} with frame :rolleyes: , personality :cool: , class ;) , & good upholestery :p , but doesn't go for a very high sheen. :D :D :D

Hairy legs, what hairy legs, I didn't see any hair. :confused:
You think that's hairy, you should see [smack] ooww, what was that for? :(

PS. I don't wear glasses to bed either.:p

Bodgy
4th October 2005, 09:37 AM
In my limited experience, I use weak Shellac as a sealer. I find it is only mandatory on end grain in soft timber. For end grain I thrown in some Talc which helps with a good finish. For general use, I apply it before you start going thru the grades of sanding. It is also very useful before glueing up, as it makes cleaning the excess easier, as the glue doesn't penetrate the wood. Not on the surfaces to be joined tho.

Try the Ubeaut site for details (grovel to sponsor).

RufflyRustic
4th October 2005, 09:41 AM
I'm starting to find the sanding sealer essential i.e. the greatest help in getting the last bit of sanding just right. I take the piece up thru the grits to 800, then apply the sanding sealer, then lightly sand with 800 again. Use a tack cloth on the piece to clear the dust, then I'm ready to put the first finish coat on. I tend to use the sanding sealer with shellac and oil finishes. I don't know how it would go under poly.

cheers
RufflyRustic

echnidna
4th October 2005, 09:45 AM
I prefer lacquer based sanding sealer, much easier to rub back.

I sand the job.
Apply the stain
Then I use the sanding sealer.
If my stain is not compatible with lacquer I use a full bodied shellac sealing coat. I only give this a light rub back to denib it.
If it needs another coat of sealer I use the lacquer based stuff and lightly rub it back.
Then I apply the lacquer (or poly etc)

On the odd occaision I use poly I still use sealer (shellac or lacquer type)

Oil finishes allow atmospheric moisture to enter/leave the timber, so a sealer
(shellac or lacquer type) is sound practise.

I suppose some may criticise this, but the question is, have they commercially produced furniture for years?

DPB
4th October 2005, 10:08 AM
I always use sanding sealer in the finishing process. If any of the surfaces are going to be difficult to access, I may apply sanding sealer prior to glue up, but it is necessary to take care not to apply to surfaces to be glued. Otherwise, I apply sanding sealer as part of the finishing process. After I have gone through the various grades of sandpaper (usually up to 600 or higher), I then apply a Ubeaut shellac-based sanding sealer. (I now dilute my own Ubeaut shellac rather than purchase sanding sealer which is diluted shellac anyway.) I apply it sparingly to avoid flooding the timber.

This lifts the nap caused by sanding and seals the end-grain. After it has dried - only takes a few minutes, I use very fine, abrasive paper to remove the nap. I find the resulting surface takes stain evenly, or serves as a perfect base for a wax finish or MinWax Wipe-on Poly.

In my experience, the use of sanding sealer is the difference between a professional-looking finish, or one that has been let down by the finish.

echnidna
4th October 2005, 10:23 AM
In my experience, the use of sanding sealer is the difference between a professional-looking finish, or one that has been let down by the finish.

ABSOLUTELY :) :)

RufflyRustic
4th October 2005, 11:41 AM
I totally agree - the difference in finishes is amazing.

Echidna, could you explain a bit more about lacquer sanding sealing? I've not come across it before.

Thanks
RufflyRustic

Driver
4th October 2005, 12:07 PM
I then apply a Ubeaut shellac-based sanding sealer. (I now dilute my own Ubeaut shellac rather than purchase sanding sealer which is diluted shellac anyway.) I apply it sparingly to avoid flooding the timber.



Don

What proportions do you use for your sanding sealer recipe?

DPB
4th October 2005, 02:37 PM
Don

What proportions do you use for your sanding sealer recipe?

It's not my receipt, Mate, I just followed Neil's book, A POLISHERS HANDBOOK.

Top of page 38. "Cut the shellac with five parts Ethanol (pure methylated spirits) to make a very good sanding sealer.":)

tyabb wonder
4th October 2005, 06:56 PM
Thanks guys for all your tips, there seems to be no set ways when it comes to finishing and everyone probably has their favourite methods.

Ive got this bottle of "french polish" lying in the shed and was wondering if it was the same as shellac. Doesnt have too much info on the bottle but it is metho based.

echnidna
4th October 2005, 06:58 PM
I totally agree - the difference in finishes is amazing.

Echidna, could you explain a bit more about lacquer sanding sealing? I've not come across it before.

Thanks
RufflyRustic

Some (spraying) lacquer manufacturers also make a sanding sealer (lacquer base) Extensively used in furniture factories.
It dries faster than shellac, sands much more easily than shellac)
Shellac can be used initially where the lacquer and stain are incompatible such as oil stain. The shellac also adds a nice patina so I often use it just for that effect (under lacquer sanding sealer)

Some manufacturers are; (in my personal order of preference)
Croda (think they've had a name change)
Mirotone.
Wattyl (from industrial paints section not your normal hardware type paint)

andyfly
5th October 2005, 03:51 AM
Hi fellas
I have nearly completed 2 Vic Ash bedside tables. I need to match (not exactly) the colour of the bed, so I am using a stain (which I don't normally do!) and I would like a decent finish
SO
Let me get this straight, is this what I do
1 sand through the grades
2 apply the stain (wattyl in my case)
3 apply the sanding sealer (shelac)
4 rub back lightly to "denib"
5 apply oil finish (Orange or Danish)

I usually just shelac and finish with orange oil and I am always happy with the result but using the stain has thrown me a little.

Thanks Andyfly

RufflyRustic
5th October 2005, 07:48 AM
Thanks Echidna. I'll check them out next time I'm getting some retail therapy :D

cheers
RR

Bodgy
5th October 2005, 09:37 AM
Ive got this bottle of "french polish" lying in the shed and was wondering if it was the same as shellac. Doesnt have too much info on the bottle but it is metho based.

French Polish is Shellac flakes mixed with Metho.

Mixed French Polish has a limited shelf life of about a year, almost none if stored in a metal container.

Not sure what happens to the fluid, after it reaches use by date, nor how the degredation manifests itself.

rsser
7th October 2005, 07:19 AM
To your second question John, you don't need to but if you want to darken the piece a bit, several coats help. If you don't want to darken a piece use n/c sanding sealer - this with a wax finish is my preferred treatment for Huon pine.

DPB
8th October 2005, 04:36 PM
Andy, I would do your step #3 prior to applying the stain.:)