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old_picker
10th March 2008, 12:15 PM
is cabots DO a moisture resistant finish?
is it likely to be marked by sweat, water beer etc?

leys say a bar top that will have sweaty arms, beer and wine etc on it or should i go for a poly only finish

i like the way the danish brings up the grain -
maybe a coat or 2 of wipe on poly over the DO might seal it??

Harry72
10th March 2008, 06:19 PM
Should be ok, you could add extra polyU to it too increase its resistance to moisture... or just use polyU.

rsser
16th March 2008, 01:23 PM
Could be the go Ray.

On it's own I've found Rustin's DO not to be especially durable. Have a fruit platter treated with it and wax and it's suffered. Granted, citrus fruits can exude some nasty stuff.

One option you have is to make your own DO but increase the poly proportion and build up the coats.

Do a google for the Blue Mountains woodturners website. There's a recipe there you could modify. From memory, theirs is 1/3 oil (eg. raw linseed), 1/3 turps, and 1/3 varnish like Estapol.

Good luck.

jerryc
16th March 2008, 04:09 PM
rsser,

I wonder if your memory and therefore your advice is perhaps faulty. A mix containing raw linseed oil would, be very slow, if not impossible, to dry. By mistake I made such a mix recently, the two linseed oil bottles were side by side on the shelf. The finish still hasn't fully dried despite being put out in the sun and also rubbed several times with wood shavings.

Jerry


Everyone is entitled to my opinion

rsser
16th March 2008, 04:20 PM
Could well be.

Check out the site I mentioned.

jerryc
16th March 2008, 04:51 PM
Ern,

Too hot to be in the workshop at the moment so I did check Blue Mountains site. They just refer to linseed oil with no qualification. Feel some people might be in for a nasty surprise.

Ray,
Check the thread "Looking for a foolproof finish" Here Wongo and I discuss the use of a well tested wipe on finish. There are two versions given and they work.

Jerry

Everyone is entitled to my opinion

jerryc
16th March 2008, 05:00 PM
Ray
title of thread I recommended is "searching for a foolproof finish".

Sorry I'm not overly great with computers and can't put in the "go to" bits to make it easier Like I always got on my school reports "Could do better".

Jerry

Everyone is entitled to my opinion

rsser
16th March 2008, 05:05 PM
Yes, there's raw and boiled linseed oil. The latter has some kind of solvent or drier or both that qualifies it for a finish. Raw needs some kind of additive, but maybe the turps I mentioned, as well as the varnish, would provide it.

That said, to return to the original query ...

In my experience DO (and I've only used three brands) makes many woods look good, is repairable but not durable. The only poly I've used is single pack Estapol, and I've found it to be durable where liquids are concerned but easily scratched and not repairable.

Ray wants the best qualities of both.

Will your foolproof finish meet the bill?

Skew ChiDAMN!!
16th March 2008, 05:49 PM
Wipe down the raw timber with BLO to make the grain ping and then spill a can of PolyU over the top... :innocent:

old_picker
16th March 2008, 06:57 PM
from what i have read of the DO finish is that it has the oil to make the wood ping, the turps to pull the finish right into the wood and the poly to make the whole deal go hard. the theory is that the hardened poly sucked down into the wood will protect it. From experience with glossy lacquers they look good to start with but scratches over time make it look crap. I am hoping the DO will be maintained better by occaisional application of carnauba withouyt having to sand down and recoat with poly

i guess the only way i can really know is to stop fiddling round, apply the finish and see how it wears
:oo:

Skew ChiDAMN!!
17th March 2008, 12:12 AM
That's more or less how I understand it works. AFAIK, the "quality" DO's have less PolyU so don't harden as quickly, hence achieve better penetration.

However, people being people, they don't want to wait a month or two for the finish to cure properly and reach full strength - they want it to dry now. So manufacturers have cashed in on this with "quick dry" DO's which are basically just a vat of PolyU diluted to the blazes with cheap oil and a Tung nut waved over the top so they can legally call it a Danish.

If it comes in a gallon tin that says you can safely walk on a floor sealed with it within 24hours, well... :roll::no:

rsser
17th March 2008, 07:18 AM
Shouldn't the wave of a Tung nut make it Chinese ;-}

This thread reminds me of a comparo of oil finishes in Aust Wood Review last year. Let me know if you're interested and I'll try to find it.

There was also one in FWW in which Minimax wipe-on poly rated best but don't ask me to recall the criteria or test procedure.

Scally
17th March 2008, 10:07 AM
I remember reading the articles.
Most of the "danish oil" finishes rated pretty well as far as look of finish.

There were some good information on resistence to water but I don't remember the details.

I like oil finishes and often add about a third poly to give it more durability.

My experience is that they don't like too much liquid on them. Wax is even less resistent to moisture.

If I was making a bar top I would have to go with a poly.
Feast and Watson Floorseal is said to contain some tung oil. I prefer its finish to most polys.

Once I finished my dining table with a two part, Mirotone (?). It is almost as hard as nails. Moisture and heat wont hurt it. Unfortunately it has chipped where something hard has been clumsily placed on it.
Plus I don't like the heavy finish.

old_picker
17th March 2008, 10:15 AM
Shouldn't the wave of a Tung nut make it Chinese ;-}

This thread reminds me of a comparo of oil finishes in Aust Wood Review last year. Let me know if you're interested and I try to find it.

There was also one in FWW in which Minimax wipe-on poly rated best but don't ask me to recall the criteria or test procedure.

AWR issue 55 pp 56 - thiking i will buy it

minwax wipe-on poly is what i am thinking of sealing with - then 0000 then carnauba

the idea was to have a 1 go finish but seems it may need to be a little more complex

jerryc
17th March 2008, 10:34 AM
I am very wary of two pack finishes. They are very hard wearing but inflexible. Wood moves and the more rigid a finish, the less it moves with the wood. Even polyurethane has flexibility problems. I have a vanity counter top under a west facing window and the heat has caused the wood to move and the finish to fracture and flake.
A softer, more flexible finish will scratch more easily but unlike a hard finish, is more easily repaired. Having had to totally sand back to bare wood a kitchen bench top that had a two pack finish, I replaced that with polyurethane. On the vertical surfaces of the kitchen I used shellac because it is easy to put on and to repair.
No one finish will do everything you want. While I am a shellac nut, but in this instance I feel a wipe on finish will be a good choice. Easy to apply so you can put on several coats, and easy to repair.

Jerry

Everyone is entitled to my opinion