Paint spec for renovated sash windows

[O'Chippy]

I have used sovereign solvent based wood preservative for years and it dries quickly and have never had a problem when overpainting it. So far in 40+ years I have not known anything rot after treating with sovereign wood preservative. If I make sash windows I would normally make a tray so I can submerge the lower part of the box window in the tray while I brush the preservative over the rest of the box. I do the same for the sashes then put sticks on top of the tray and stand the box sash on them so any surpulus drips back into the tray.

Regarding paint it does seem that: Tikkurila otex adhesion primer then valti ultra topcoat is popular. The top coat is supposed to be flexible and last between 8-12 years which is very good. I have used Santex in the past and generally obtain around 8 years before a re-coat is needed. But I might give the Tikkurila otex adhesion primer and valti ultra topcoat a try if I'm spraying or even brushing because it sounds very good.

Thanks for the response @meccarroll.
Good to hear your extensive experience of using wood preservative and how overpainting it has performed for you. I'll add sovereign to the list.

Yes the Tikkurila otex adhesion primer/valti ultra topcoat is popular.
I'm in the process of selecting a sprayer, the "pro-sumer" Graco A30 was the frontrunner however it cant handle solvent based paints (or anything with a flash point <100deg), therefore I'm also consider the Graco GF21 which is a professional machine but obviously more expensive.
I need to figure out if I can live without the need to use solvent based paints or if the upgrade is a wise selection.

 

[Doug71]

I tried the Bedec MSP and found it very thin, it needed multiple coats although this was in white and I think most modern white paints suffer from this. That was brushing on, not spraying though.

 

[deema]

I recently went through the same selection process of a an airless paint sprayer. I went down the Wagner route and selected the followimg
https://www.paintsprayer.co.uk/wagn...IzeQNasVW5phPF6W7HzoaetnbQt75VnkaAo2CEALw_wcB

It can spray both water and solvent based paint. I was lucky and picked up a secondhand unit for a fraction of the new price. May be worth taking a look. Wagner also own Titan, which has a lifetime warranty on the pump, ie it doesn’t wear out. The two units look almost identical, so I decided knowing a little about manufacturing that it would be highly likely that the same pump is within both units. Spares arnt too bad in a worst case scenario. The ‘big’ advantage from Greco appears to be that you can change the pump without tools. For me, if you don’t need to change the pump, that’s a much bigger advantage.

 

[deema]

I tried the Bedec MSP and found it very thin, it needed multiple coats although this was in white and I think most modern white paints suffer from this. That was brushing on, not spraying though.

A highly regarded and very knowledgeable architect who used to post on here highly recommended Bedec paint, if memory serves he used to state that it was the paint he specified for all external joinery.

 

[O'Chippy]

I recently went through the same selection process of a an airless paint sprayer. I went down the Wagner route and selected the followimg
https://www.paintsprayer.co.uk/wagn...IzeQNasVW5phPF6W7HzoaetnbQt75VnkaAo2CEALw_wcB

It can spray both water and solvent based paint. I was lucky and picked up a secondhand unit for a fraction of the new price. May be worth taking a look. Wagner also own Titan, which has a lifetime warranty on the pump, ie it doesn’t wear out. The two units look almost identical, so I decided knowing a little about manufacturing that it would be highly likely that the same pump is within both units. Spares arnt too bad in a worst case scenario. The ‘big’ advantage from Greco appears to be that you can change the pump without tools. For me, if you don’t need to change the pump, that’s a much bigger advantage.

I haven't looked at that particular sprayer but looks like a good option.
Interesting that it can spray solvent so I had a look if the wagner DIY machines can also spray solvents and it appears that they can.
That to me seems like a big advantage over the more expensive Graco A30

 

[deema]

I have to say, my first ‘have a go’ with airless was with a Screwfix Erbauer EAPS600 Electric Paint Sprayer 600W that costs c£200. It has both a primary and secondary filter and can take any of the standard nozzles from Wagner of Graco. It’s 200 bar pressure so the same as the premium brands. It comes with a 5 year warranty. Now, the pressure setting is a bit crude, but otherwise is lasted for around 150 litre of spraying before the pump started to give in. I got my money back and bought the Wagner. The point I’m making is that it’s the nozzle that determines the finish as long as you have sufficient pressure…..which this unit has. The finish it produced was excellent with the cheapest water based paint I could find that had the consistency or porridge and the nozzle it came with. It can spray solvent paint too.

 

[O'Chippy]

I have to say, my first ‘have a go’ with airless was with a Screwfix Erbauer EAPS600 Electric Paint Sprayer 600W that costs c£200. It has both a primary and secondary filter and can take any of the standard nozzles from Wagner of Graco. It’s 200 bar pressure so the same as the premium brands. It comes with a 5 year warranty. Now, the pressure setting is a bit crude, but otherwise is lasted for around 150 litre of spraying before the pump started to give in. I got my money back and bought the Wagner. The point I’m making is that it’s the nozzle that determines the finish as long as you have sufficient pressure…..which this unit has. The finish it produced was excellent with the cheapest water based paint I could find that had the consistency or porridge and the nozzle it came with. It can spray solvent paint too.

@deema Can you shed any light on what determines some sprayers rated to spray solvent based and other not so? My understanding is that it regards the sprayer's ability to safely run solvents with low flash points, something to do around with how the machine is grounded, if it is brushesless or not......
Its seems that there are oil based solvents with relatively higher flash points (which some diy machines can safely use) and there are true solvents with low flash points which general only the professional level machines can safely use.
Perhaps there is some fudging going on from the manufacturers claims regarding the ability of the diy machine?