# Help - I need a substitute for knotting!



## Eric The Viking (23 Jul 2010)

Deep joy: 

I've almost finished the nastiest pair of window frames you can imagine, for the garage to replace a rotten pair, attacked by potential burglars with screwdrivers a few weeks ago. They're made in horrid pine, that's got shakes, gone warped and done all sorts of horrid things in the time it's been in my ownership (thanks B+Q - do the same for you any day!). 

To make my joy complete, I now find I (idiotically) gave away my last bottle of knotting. And I need to paint up the frames ASAP. 

I've got some as yet untried sanding sealer - would this be any good as a substitute? 

To cap it all off, I'm sitting in the box room typing this on a laptop, as (a) I think we have mice from next door, and (b) I think they just ate through the CAT5 spine cable running across the attic & down the house. 

A CAT is evidently what we need, later, meanwhile, I need to sort the window frames to make the garage tea-leaf-proof again.

So what to use for a knotting substitute? I have other things, like cellulose varnish, and polyurethane, so I'll take direction!

Cheers,

E. 

PS: Daughter just passed Grade 2 flute at school. I wonder...


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## DeanN (23 Jul 2010)

Any aluminium wood primer to hand ???


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## Eric The Viking (23 Jul 2010)

DeanN":14yyxf5o said:


> Any aluminium wood primer to hand ???



Thank you Dean, very much indeed -- I think I may have! 

I haven't opened the tin for some while, but I think it's white spirit-based - can check if it's any good. 

Do you think that will do the knots and the end-grain? I intend a thorough priming and glossing afterwards, as they fit into concrete openings (Marley's finest) and take a lot of weather in the winter.

Cheers,

E.


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## DeanN (23 Jul 2010)

I've always used knotting myself, but was recommended aluminium wood primer as an alternative by a local decorator. I've just finished a gate, using this as a primer under exterior eggshell - looks good, time will tell on the knots though!!

Some info from the Crown website: http://www.crowntrade.co.uk/PRODUCTS/PR ... rimer.aspx


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## Dibs-h (27 Jul 2010)

I've used knotting with mixed results under exterior paint. Going forward, I think better results would be had by creating a slight recess - router\chisel and letting some epoxy in.

In some cases with knotting solution - the extractives have come thru, especially in areas where the sun is hitting it all day.

HIH

Dibs


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## mailee (27 Jul 2010)

If your sanding sealer is shellac based then it will be fine. As for your mice, Tomcat blocks work great I used to be inffested with them until I used these. :wink:


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## Eric The Viking (27 Jul 2010)

mailee":1phzm8as said:


> If your sanding sealer is shellac based then it will be fine. As for your mice, Tomcat blocks work great I used to be inffested with them until I used these. :wink:



Thanks to all. I rejuvenated some old aluminium primer (stirring over several days seemed to sort it). 

The 'mice' turned out to be 'virtual'  

Cheers,

E.


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## Jacob (11 Aug 2010)

What's wrong with knotting? Shellac is just about the best and most durable primer there ever was. I've found it still in good nick on windows 200 years old.


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## Eric The Viking (11 Aug 2010)

Mr G Rimsdale":1qlx5emk said:


> What's wrong with knotting? Shellac is just about the best and most durable primer there ever was. I've found it still in good nick on windows 200 years old.



Firstly, I didn't say there was anything wrong with it. I just didn't have any to hand at the crucial moment. 

Secondly, the durability of paint systems is enormously dependent on the overcoatings (the finish depends on the surface prep). Anything over, say 40 years old may well have lead oxide in the paint, which makes a huge difference to the durability. Modern paints are pants, and water-based ones are worse*.

I think, if you find 200-year-old windows in good nick, there are a number of factors that have little or nothing to do with knotting's durability per se.

In this case the frames had two or three good coats of aluminium primer, put on with a hosepipe (and trowelled off, soaking the end grain and the returning corners). That was followed by what should have been two coats of undercoat, but ended-up less as the weather turned on me. One coat of gloss, presently, but they'll get more if it stays fine. They've only got to outlast my tenure of the place, but they should go for a while, I'd hope.

Cheers,

E. 

*Lifelong "_friend of McGonagall_"


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## azzert (21 Jun 2017)

Sanding Sealer is a shellac based solution so is very similar to knotting


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## garethharvey (21 Jun 2017)

I have used shellac, then over painted with Linseed Oil paint, never had any problems. As you say: modern paints are pants


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