Months ago I pinched my sons jar of Hair Gel to try it out. It is an inexpensive supermarket brand and does the job beautifully in controlling my brushes of all types. If we can put it on our hair without it falling out or change to a weird colour I can’t see that it will hurt and after months of using Hair Gel on my own brushes, I can recommend it.
After each painting session I rinse the brushes out in water or turps (depending on the type of medium used). I then wash my brushes out in warm water and pure soap, no matter what medium I have used. Do this by rubbing the brush onto the soap, rinse and rub onto soap again and rinse until the brush does not soil the soap. One last rinse than remove excess moisture on a cloth, dip in the Hair Gel, shape and allow to dry. It might be wise to rinse the gel out of the brush for watercolour painting but I don’t bother for oils.
It isn’t unusual for me to place a stubborn flat tipped brush that doesn’t want to be trained under the edge of a large cutting mat on my table. It is sufficient weight to hold the fibres together until the gel is dry.
If you would like to share by commenting to this post how to gain a longer life for brushes, I would love to hear from you.