Archive for the ‘troubleshoot’ Category

Nail Putty Problems

October 20, 2007
There is growing number of reports of nail putty problems on pre-primed trim products. I will touch briefly on one of the main causes for what you see in the photo. This ringing effect around the nail hole is caused by use of overly oily oil-based nail putty. What happens is this, after the putty is pressed into the hole (usually within hours), the oils in the putty seep through the wood fibers and rise to the surface via the super absorbent factory primer coat leaving an oily ring.

Explaining in more detail: the quality of the primer coat on factory pre-primed trim is so poor that it can be dissolved with just water. The primer coat is about the same as if you put cheap flat wall paint on bare wood. The oils in the putty soften the primer coat leaving an oily spot. When you paint over this oily spot, your finish coat absorbs into the soft spot. This occurs with oil-based paint or Acrylics.

The work around: 4 Options
1) Re-prime that crappy factory primer before you do any nail hole filling.
2) Use a latex putty vs. oil.
3) Use a product such as DAP CrackShot or DryDex (much more time consuming) best results.
4) Use Whiting Powder to dry out the putty a bit.

In new home construction it is far less expensive and labor intensive to simply spray a new coat of primer on the trim. The factory primer is applied to the wood with one goal in mind, to fill imperfections in the wood.

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Painting Cedar Shakes

October 11, 2007

This week a reader wrote in with questions on how long he should wait after power (pressure) washing his house of cedar shake siding.

I know so many paint contractors who will go wash a wood house on Monday and shoot paint on the house Tuesday.

If you think for a second that the house had enough time to dry, you are sadly mistaken and just asking for troubles.

Take a look at the photo on the left. In just a short time the cedar soaked up enough water to where its wet two inches up the board. The most common place on cedar shakes that paint or solid stains fail is the bottom edge of the lap. This wicking effect is absorbing water and drawing the water up the board and even under any paint left on the laps. Moisture under a paint film needs more than over night to dry. The top photo shows the cedar cut with a saw to show how much and how far into the cedar that water goes.

ProForm Compound Issue

April 30, 2007

We currently have an issue and looking for a solution to painting over ProForm joint compound made by National Gypsum. We have two drywall finishers and they use ProForm Lite and ProForm Topping products.

The problem we are experiencing pertains to applying eggshell paint over their finish work. We have two separate issues. One is the paint absorbs excessively into the horizontal joints but not the patches made over screws.

The problem we have with the patches over screws is the opposite. The paint does not seemingly absorb at all (see photo #2), resulting in a shinier area over the patch and even with 2 coats of eggshell, the patched areas become noticeably shinier than the rest of the wall even when a wall primer is used.

Here is what we tried so far. We applied the following wall primers to the bare drywall with varying results and in most cases, worst results vs. painting eggshell directly over bare drywall.

1) ICI 1010 Prep & Prime Stain Jammer
2) ICI 3210 Prep & Prime Gripper Multi-Purpose Primer Sealer
3) Kilz 2
4) Sherwin Williams PrepRite Classic Primer
5) Zinsser Bulls Eye Water-Based Primer
6) ICI Dulux 1000 Prep & Prime Hi-Hide Wall
7) Sherwin Williams PrepRite® High Build Interior Latex Primer/Surfacer (what a mess)

We tried all of the primers above with 2 coats of eggshell paint for finish. Most primers enhanced the screw patches making them stand out shiny.

Today we applied Zinsser Gardz to the horizontal joints as seen in the top photo and this photo. The Gardz worked very well sealing the horizontal joints. We applied Gardz to a few patches over screws and it appears at this time it may work.
This photo shows a close-up of Gardz over the horizontal joints and how it dried over the mud.
This photo shows one coat of eggshell over the bare drywall with Gardz placed only on the horizontal joints. This is what we expected any of the 7 primers to do to the joints. I will let the 1st coat dry a few days and try 2nd coating an area to see how it dries down. At this point, we tested about 10-12 different eggshell paints with this issue. More to come…

Additional info: If we were to take USG Topping and make a new patch over the existing patch in the (blue wall photo) above and repaint the new patch, problem solved. I am unable to find any help on this topic. I wrote National Gypsum 4 days ago and no reply. None of the drywall finishers I know use Proform so there seems to be a lack of experience with the product.