Many older bathtubs become worn out and the finish gets scratched and ugly looking over time. Older bathtubs can also be odd colored with colors that are no longer in style. Replacing a bathtub can be an expensive, time consuming project that requires ripping out portions of your wall to remove the old bathtub. Having your bathtub refinished eliminates this costly and messy tear out procedure and you can have a new looking bathtub in less than a day.
There are some issues with refinished bathtubs that can occur when recaulking a refinished bathtub. The epoxy coating that is applied to a refinished bathtub is not as durable as the original baked on finish that is applied to new bathtubs. Therefore removing the old caulk from a refinished bathtub can be a difficult procedure to do without damaging the bathtubs epoxy finish. Often times caulk that is applied after the bathtub is refinished is not a high quality 100% silicone caulk and this caulk can get black and moldy in a short period of time. Also there are many different grades of epoxy finish that can be applied to a bathtub. Some cheap epoxy finishes are not very durable and can easily be scratched and chipped away. Also many cheap epoxy bathtub finishes will peel away when the caulk is pull out of the refinished bathtub.
It takes a lot of skill and patience to remove old caulk from a refinished bathtub without damaging the epoxy finish. It is nevertheless still necessary to remove the old caulk before installing new caulk when recaulking a bathtub. You never just want to apply new caulk over old caulk when doing any kind of recaulking procedure. Also you do not just want to leave black moldy caulk on your bathtub as this looks ugly and the mold can create health problems for your family and pets.
When removing old caulk from a refinished bathtub you should first use a utility knife to cut through the old caulk. The utility knife should be angled so that it only scratches the area of the bathtub where new caulk will be applied. Using a utility knife this way will make it a lot easier to remove the caulk that is attached to the refinished bathtubs surface.
After cutting through the caulk with the utility knife then you should use a window scraper tool to carefully cut out the caulk that is attached to the bathtub. You should use gentle movements with the window scraper and only cut out the old dirty moldy caulk and do not cut into the refinished bathtub. Often times the bottom layer of caulk will be permanently attached to the bathtubs epoxy finish and you may have to leave this layer of caulking there. There is no point to removing caulk on a refinished bathtub if it will peel away the finish. You should never just pull away a section of caulking from a refinished bathtub. Peeling away caulking in this way can also pull away large sections of the epoxy finish and ruin the finish of your bathtub. After you have scraped away as much of the old caulk as possible then you can use isopropyl alcohol to clean the surfaces that are about to be caulked.
When applying new caulk to a bathtub it is best to tape up all edges that need to be caulked to ensure that a nice straight caulk line will be formed. Tape off the bathtub and the adjoining wall approximately 1/8th inch and apply the caulk. You should only use 100% silicone caulk to ensure the new caulk will not grow mold in it like the old caulk did. After you apply the caulk then smooth it with your finger. After you have smoothed the new caulk with your finger then you should remove the tape and re smooth the caulk with your finger. Taping off the caulk line and smoothing the caulk with your finger will give you a much more even and straight looking caulk line than you could of obtained without taping off the caulk joint.