Tongue and groove advice

[Arquebus]

Hi,

I need to paint the inside of several T&G doors in my cottage, both internal and external. Over the years the backside joins of the boards have opened up leaving unsightly gaps, as in these photos.

The troughs created are only a few millimeters deep, as the internal 'tongue' part of the joints is still good and fully connected.

My instinct is to seal them with decorators caulk and smooth it off with a scraper or an old store-card, before painting. But I'm wondering if flex from opening & closing the doors, and temperature fluctuations will make it all fall out again?

Any thoughts or suggestions of the best product to use?

 

[Toby Newell]

Personally I don't mind the gaps, I would just clean the gaps to make them even (paint job seems quite poor) and paint inbetween.

You could try using a modified silane type adhesive sealant, this remains permanently flexible and can move 20% after drying.

I use Everbuild Multi Stick (which came out years before CT1 btw, I just bought 20 more of them last night) you have possibly heard of CT1, pretty much identical stuff but over twice the price to pay for all the marketing.

I have only ever used it as an adhesive but apparently it's a good sealer and it's overpaintable. I suggest buy one tube, clean the gaps and test a small area.

I use dozens of kilos of fillers a year on wood, never used caulk, true caulk sets very firm. Bear in mind wood's propensity to move can overcome pretty much any glue, filler or adhesive if the moisture difference is great enough.

 

[Arquebus]

Thanks, Toby!

I was unaware of 'paintable', flexible sealants so this seems worth an try at least.

What do you use to clean or wipe down with?... Some kind of solvent?

It should be easy enough to pipe it into the cracks, but assuming I then can't sand it like a hard wood filler, I will need to smooth it off with a rag or something, without getting in a godawful gungy mess.

 

[Toby Newell]

I never need to clean down. I expect some kind of solvent, either white spirits or acetone. I don't advise it though.

I would clean your gaps and sand the whole door well, it looks badly prepped and coated, then clean and dry.

I would then mask the edges with a quality tape like Fossa or 3M.

Then I would 'pipe' in the sealer and scrape the excess off immediately and remove the tape before it dries.

You can use universal builders wipes to clean your scraping instrument and your hands.

I wouldn't try and sand it. It eventually dries to Shore A 60 hardness which is quite firm but this can take a week. I guess you could sand bits which go over the edge but I wouldn't sand the bead.

Bona say you can sand their gap master filler but I doubt it and never tried it.

Tbh, I only fill gaps if I think the wood is going to be reasonably stable, if there is mega movement, like in bathrooms, I don't bother as everything comes loose.

This is supposed to be good, I only use it as an adhesive but I was a very early adopter 16 years ago when you couldn't buy it in the shops. Has been used in the flooring industry since that time.

You can think of it as a Frankenstein cross between a polyurethane adhesive and a silicone sealant, so either a stronger silicone or a more flexible glue.

Let us know how you get on!

 

[Arquebus]

I'll experiment on the worst one and see if it's worth all the effort! Thanks again.

 

[Toby Newell]

without getting in a godawful gungy mess.

I have used over 1,000 tubes and over 500kg in tubs and foil sausages, so probably a literal tonne. Still not found a way to avoid that ^^^

 

[noj]

If you're after the smooth and shiny look then you could embrace the 1960s approach and cover the door in a sheet material (used to be hardboard)! This would leave the original t&g free of filler and may be welcomed by a future owner with different taste...

 

[Toby Newell]

not sure thats really a 'thing' with those hinges and door furniture. Moot anyway as in damp conditions you would have to slather in adhesive, 16G pins aren't going to hold onto 3mm hardboard without it ballooning.

3.3mm ply would be a minimum glued and pinned, would do more damage than filler. Filler can at least be routed out or removed with an oscillating tool, rather than scraping and sanding adhesive over the entire door.

As I already said, I like to go with the flow myself, the wood want's to move that much let it, just tidy up the gaps, but people have different aesthetics.

 

[Toby Newell]

I actually prefer the gaps as a feature! If I were making a braced door I would be inclined the chamfer the edges to make a feature of any gaps. But it doesn't look very old does it? No harm nor foul really.

 

[Toby Newell]

This is possibly from 1407, it's bad enough someone painted it, can't flippin find the photo of the reverse, which is chocolate brown raw oak. Now filling that should be punishable by flogging...



It's about 1.6m high, so in 1407 Britain must of been populated by Hobbits.