Isopon P38

[bolst3r]

I have 2-3mm gaps in wooden front door panels. Filled it a few years ago with polyfiller but they’ve come back. Expect it’s a combination of shrinkage, vibration and poor quality product (and my bad skills of course)

If I try and scrape out any old stuff is P38 a viable solution for the long term? Seems it referenced lots of times on here...

Planning to prime with bulls eye 1–2-3 before undercoat. With regards to the undercoat is there another quality quick drying product like bulls eye?

Being out on a main road it’s difficult leaving the door open unattended for a day. It’s what keeps putting me off doing it

 

[JohnD]

You need to clean out the old paint round the panels, which is causing the splits in dry weather. Filler in the cracks will not stop them.

Post some photos of the panels, especially close ups of the side and bottom of the panel showing its joint.

It will be easier if you can lift the door off its hinges to work on and hang it back at the end of the day.

 

[opps]

I agree with JohnD.

When the weather is warm and dry the wooden panels shrink. If they are unable to "float" in their recess any filler that you use is likely to crack.

You could use a very sharp filling knife to break the existing paint seal between the panels and the styles and rails. A sharp filler knife is preferable to a chisel because it is much, much thinner. Alternatively, if you have access to an oscillating tool (multitool) you could use a scraper blade.

You could then refill the existing cracks. 2 pack fillers such as Ispon are great but not very flexible. An epoxy resin filler will allow for a greater degree of movement but they are much more expensive. Lightweight fillers such as Red Devil Onetime or Toupret RedLite are more flexible than 2 pack fillers but they are quite soft.

When you have filled and sanded, consider a MS polymer "caulk" (eg CT1, Sikaflex, Stixall) to fill the newly created gap between the outer edges of the panels and the rest of the door. Be warned that you need to apply waterbased paints over them first. Oil based paints wil take months (literaly) to dry when applied directly over MS polymers.

I often use waterbased Dulux trade Weathershield waterbased undercoat but even the cheapo Leyland acrylic primer (£10 for 2.5L) will be fine.

You can then apply a coat of Dulux Weathershield oil based undercoat. It is touch dry in a couple of hours, and door safe in 6 hours (?). Their gloss however needs a full day before you close the door (paint additives such as Terebene will speed up the curing process- price=£6 and will last you for years.

Ispon P38- effin expensive. I can buy 2k filler for £18-20 via ebay- that is for 4L. I am guessing that the likes of Halfords charge £10 for 0.5L

 

[bolst3r]

Massive Massive apologies on the delayed response, seems I wasn't getting alerts to my email so thanks for taking the time to answer my question.

Here's recent pictures of the door in question... is this beyond saving?

Being the front door it's difficult to work on for long periods... I did consider trying to but another used door of a similar size that I could either fix up or hand whilst this one is removed and dealt with properly but I can't really find any that fit...