# Gesso primed woodwork?



## Flhden (Jan 20, 2008)

Here in Rhode Island most new millwork is coming through preprimed with a very thick coating that I was told is called Gesso. I also understand that it is a plaster, paint mixture as used on painting canvas. During installation if hit it chips and requires a woodfiller blending. On a recent job a piece of casing was left in the driveway overnight and we had a light shower that night. In the morning when we arrived at the jobsite all the primer had washed off and turned the surrounding area white. We spray BIN pigmented shellac as a reprime on all interior woodwork, and doors and topcoat with 2 coats of oil base satin impervo. Have had no problems with this new primer until recently when we were called back by the GC to address a bubbling situation on flat stock doorjambs only. Lumber yard rep, millwork rep, Gc and I met to review. It appears that the pre primed jambs were pine with knots everywhere. We never knew this as the primer hides everything. Now during the first heating season it appears that every knot is causing the thick primer to pop. All other areas are perfect. Luckilly the millwork co is going to pay for complete replacement and repaint which will include new casings on both sides of jambs, and wall repair. No sealer or shellac was ever applied to the knots before applying the gesso primer. I was also told that the millwork is actually shipped to China for priming for price reasons. The wood industry is shooting itself in the foot again with this approach as far as I am concerned. This is my first post on this forum. Have been a painting contractor for 38 years now taking over the business from my dad who did this his whole life also.My intent is to warn other painters of this potential problem and see if anyone else has experienced this new prime system so prevelant here in the Rhode Island area. Thanks for reading, and sharing any info.
Den


----------



## FoilEffects (Dec 19, 2007)

In both Illinois and Florida we had both pre-primed MDF trim and pine trim pre-primed the same way. Yes Gesso is what they coat canvases with and yes that is what is shot down a spray tunnel onto the trim that comes pre-primed. As you may or may not know, once a primer has sat open to the elements for more than a period of 2 weeks it starts to break down. I like the trim only because it takes fewer coats to get it solid but I always do my putty and caulk, then sand and re-prime the base and case prior to coating it with paint. IMO that is the only way to go and gesso is a very weak primer to begin with that is very very cheap to begin with.


----------



## Joewho (Apr 17, 2007)

The gesso is used for obvious economic reasons. Mostly on new construction or diy projects.

Even though the mill company stepped in on this one, it's still cheaper to get preprimed, rather than paying a painter to do it right:furious: .

Some painters insist on priming it anyway. Most builders would never stand for it though. It's either paint the pre-primed or prime bare wood.


----------



## Tmrrptr (May 4, 2007)

Flhden, someone is being sold a bill of goods here..

Gesso is a marginal product, especially for an application such ast wood trim stock that may not be stabilized yet...

And someone is using who knows what blended in their formula for the gesso.
They are just using the opportunity a cheapo trim supplier presented to get rid of lead based, and melamine based products over in China while they garner a few bucks for the labor of applying low quality primer.

Get you trim from another source.
Be sure to tell supplier why you are leaving them.


----------

