Please describe your method and materials for blocking warped watercolor paintings. Thanks!
Sandra Wall Armitage
I haven’t ever needed to do this.
Kathleen Baker
I would remove the warping first by placing the paper on a smooth folded bed sheet on a hard surface, finely spray it with water and iron it with medium heat, upper surface facing downwards. Then, I’d put the paper between two boards with weights on top.
Susan Dalton
I’m not entirely sure what you mean when you say ‘blocking warped watercolour paintings’. If you mean flattening paintings that have buckled when dry then I would suggest you try one of the following methods:
a) If the paper is not too warped then you could try gently ironing the back of the painting and then placing under a heavy weight for a couple of days – I have tried this on one or two occasions and have found it to be quite satisfactory.
b) If the paper is very warped I have heard of artists wetting the whole of the back of the paper and then stretching by taping it down to a suitable clean board with brown gummed tape until totally dry – however I would find this method too much of a risk!
Ideally prevention is better than cure and I would suggest that you either stretch your paper before you begin painting, use a heavier weight of paper or (as I do) use blocks of watercolour paper.
Brigitte Daniel
I mist the back of the paper using a fine spray (used for plants) several times (letting it
soak in each time). I then lay the paper wet side down on a board sealed with yaught varnish and stick down the sides all around the edges using brown water-based paper tape. I then let the painting dry. Keep an eye on the fine detail between sprays to make sure it does not run. Try to avoid this problem by using heavier paper.
Susan Hillier
Wet the back of the painting, and a wooden board. Tape the paper down with Gum Strip and let dry naturally.
Jennifer Jenkins
I never have this problem as I use Aquarelle Arches 140 lb. blocks and 140 lb. weight sheets of Fabriano paper for my watercolour paintings.
Kay Rees Davies
I ask my picture framer to dry mount any painting which might have buckled slightly.
Margaret Stevens
This is not a problem I have encountered. I try to use sufficiently heavy paper suitable for the painting and try not to get it too wet. I also prefer to work on blocks of paper rather than loose sheets which helps a lot.
___________________________________________________________________________________
Continue to Nature’s Colors
Return to Day Job
ArtPlantae Today 
Thanks so much for all these great suggestions….so many different responses allows me to try various methods. What a great service you are providing!! Sending you a big virtual hug!