The only solution now is to remove all of the paint down to the wood and stain it with an oil base solid hide stain.
Removing paint from redwood siding.
It can be painted on just the way you.
If necessary remove any knobs hinges or other hardware from the wood being sanded.
You can also use a roller or paintbrush to apply it to.
Stir the paint stripper thoroughly with a mixing stick and pour it into a pump sprayer.
Just be sure the heat gun you choose is a low temp heat gun below 1100 f so as not to release any lead paint fumes and wear a respirator.
Solid hide stained would be perfect for this siding.
Redwood is very resistant to decay.
Clark and his crew considered using several different methods on the winchester siding before making a final choice.
After putting on protective gloves and a face mask fill a small bowl with the paint stripper grab your brush and begin applying stripper to the old paint.
If it is already painted you will want to carefully strip the paint away with scrapers and sandpaper.
All of them are hard work because the same binders that cause paint to adhere make it hard to remove.
So the surface should be sanded to get down to fresh clean wood.
This siding should never have had paint on it to start with.
How to strip paint off wood siding.
Thoroughly clean the painted surface with degreasing cleaner dish soap or household cleaner and allow to dry.
Spray the painted wood siding thoroughly.
Make sure to take the time to invest time in this process since the preparation exposes the initial layer of redwood allowing it to breathe and absorb the primer and paint.
Dip a thick nap roller into the paint and use the ridged portion of the tray to roll.
If you don t put paint on the siding to start with it can never peel off.
You will never have any cracking blistering or peeling.
Open the paint can and gently stir the paint being careful to avoid air bubbles.
Paint thinner or acetone is said to remove paint stains but may also dull dull the finish on your siding.
Consult your hardware store about the condition of your redwood siding.
To use sandpaper or a power sander to remove paint.
Stripping old paint with a heat gun might be an option you could look into.
Fill a paint tray with paint.
I suggest thinning it with 1 part thinner to 10 parts water and scrubbing on the stain only after testing a small inconspicuous area.
Stained wood siding is about as maintenance free as wood siding can get just give it another application of stain about every 10 20 years.