I’ve found that if you mix a small batch of plaster and glue, a bit heavier on the glue, that you can paint over the surface to fill in the bubbles. Mix two parts PVA glue with one part water in a bucket. The glass results in a white colored filler, the phenolic a walnut brown. Dip a paint roller into your mixture and allow it to absorb some of the PVA mix. Registered User. PVA and Uses With Timber Alternatively, you can use PVA glue, or better (and cheaper), PVA glue watered down. Allow the mixture to dry. We recommend the Unibond products – their mix is thick and acts as a great sealer for plaster. Then you can sand them smooth (thanks to the wood glue). I use my stock of Cascamite to make my own wood filler. Can I fill the floorboard gaps with the PVA and sawdust mix and THEN sand the floorboards afterwards? PVA glue is only good as a filler when mixed with balsa dust and then only to build up an area before you do the final coat in Bondo. PVA in Cement and Mortar. PVA based wood filler is a poor substitute for a cascamite based easy sand filler. He didn't however, use it as a primer but would mix it with the paint and water to create in effect a mist coat incorporating the pva. However I am told that the pva/sawdust mix will go brittle over time and work out of the gaps. Rodney. The reason I recommend using high-quality filler is that PVA, even when fully dry, tends to clog up the belts when you are sanding the filler off the surface (I’ll explain in a moment). You know when PVA glue dries when it is no longer white. You can see what it looks like in the ‘Mixture 3 Smooth’ picture above. You may have experienced the use of PVA glue mixed with sawdust as a wood filler. I can recall working with an old guy who was a pretty good decorator and well skilled at his trade and there were occasions when he would use pva . Paint a coat of PVA glue mixture evenly on your applied mortar. The general mix for PVA is 3 parts water to 1 part PVA (3:1). Apr 11, 2007, 03:48 PM #12; Rodney. Painting a coat of PVA on the surface before the cement mortar is applied can even further increase this adhesion. I’ve seen a suggestion that the filler can be a mixture of sawdust and pva. Some companies PVA’s are weak, thin and very poor in quality so get a decent one. Or is there a reason I shouldn't do this? I’ve experimented by inserting some of the mixture into a length of gap using a refilled 310ml decorators caulk tube. I'd love to do the filling before the sanding for logistical reasons too boring to go into here! PVA can be added to a cement mortar mix to give the mix a) slightly better waterproofing qualities and b) advanced adhesion to the surface it is applied to. Using a small brush ...paint in some neat PVA into the hole(s). We need to mix the PVA with water because it’s far too thick to apply as a stand-alone material. So in short, I would mix up a batch of matt emulsion (preferably contract but definitely not silk) with about 40% water and apply to all the new plaster/filler. I have filled and sanded my walls in numerouse parts, can i use pva to seal/prime the filler before painting. The beauty of this filler is that it is hard enough so you can sand it easily. While that is getting tacky.. have the amount of filler you need ready and add about a teaspoonfull or more of neat PVA before adding the water and mix in the usual way...fill the area(s) and leave a little proud .The adhesive in the mix bonds with the prepared area . There are two common types of micro balloons, glass and phenolic. When exposed to water, PVA will actually dissolve, which makes it a very useful support structure material for 3D printing. That way you can get high-quality filler, whether water-based or not. PVA, or Polyvinyl Alcohol, is a soft and biodegradable polymer that is highly sensitive to moisture. Hi, my local timber merchant has offered me sawdust if I want to use it for floorboard gap filler with PVA.