Preparing and varnishing garden room - tips for sanding

[C0mbat]

Hi all,

We need to revarnish our garden room. We don't know what varnish was used before so I'm assuming to we need to sand it all back?

With the sanding, it looks as though it will be really tricky because the panels overlap. Has anyone got any tips on the easiest way to sand it? See the photos.

 

[Wayners]

Id use a festool ro90 to sand.
Metabo make a cheaper version

 

[C0mbat]

Thanks. So an orbital sander of some sort or something very specific?

Ive got a Worx detailer sander right now (just the triangular shape) but I was assuming that wouldn't really help much?

 

[Wayners]

Try it with 100grade

 

[C0mbat]

Try it with 100grade

Thanks. So just try the Worx Detailing Sander? Don't bother buying an orbital one?

Also, should I use varnish/paint stripper first?

 

[88v8]

Also, should I use varnish/paint stripper first?

Not unless the existing varnish is coming off.
If it's sound, all you need to do is key it.

 

[C0mbat]

Not unless the existing varnish is coming off.
If it's sound, all you need to do is key it.

Thanks for this. My father in-law told me the same thing over the weekend. There's no need to fully sand it back to the wood. Give it a light sand and then put new varnish over it. I was under the impression that you had to go back to the wood. It's saved me a huge amount of time!!!

 

[justigator]

I've just repainted my 5x4 metre garden room, which doesn't have overlapping panels. I couldn't bear the work of sanding, even lightly to provide a key, so I used HG Liquid Sander diluted 10-1 and scrubbed on with a dustpan brush then rinsed off with a hosepipe and more brushing where necessary, then left to dry. Good results. It seems to be basically a powerful detergent rather than an abrasive liquid, as a product that seems no longer available called IIRC Liquid Sand used to be (it was like Cif - grainy - but red in colour). Again IIRC, Liquid Sand required the relevant surface to be painted within six hours but the HG product I just used doesn't say anything about that - although obviously it would be unwise to wait too long. Whatever, both these products need or needed copious amounts of water to wash off, so not really very suitable for interior use.