We have a pipe fence that we had painted last summer. Because we had no way of knowing if the existing paint is water base or oil, we treated with TSP prior to painting, then painted with a water base FENCE paint from Tractor Supply. Quite a bit of the fence is already flaking BADLY. Obviously, we want to paint again, but how do we avoid this happening again? Do we 'assume' that we need to use an oil base or ???? TIA
TSP is a detergent solution. It will not make water-base paint adhere properly to an oil-base paint substrate. That requires a primer designed for that purpose. (Most folks would use an oil-base bonding primer, but there are water-base formulas for this purpose as well.)
You will need to power-wash and/or scrape and/or sand the failing paint until all the loose stuff is removed, clean, scuff-sand, and then topcoat with bonding primer and then the water-base finish of your choice.
Thank you much for your prompt response and wisdom! I guess we were misinformed the first time around. *sigh* But, at least NOW we have correct information and can remedy the problem and avoid having it happen again. Live and learn. The good thing is that this was only on one long run across the front of the property. Do I just ask for a bonding primer that is being applied to metal? Do you have a preference for an oil or water base primer? Thanks again for your help!!