Home-repair tips for sinks, windows and more

Q: My porcelain bathroom sink has developed a hairline crack that is almost invisible, except when dirt gets into it. It does not leak. Is there anything I can do to make sure it doesn't leak?

A: That porcelain is china, the same as on toilets and toilet tanks. For starters, just leave it, and keep it clean. It may not get bigger and may not leak for a long time. If it starts to leak, try one of these processes.

First, paint a bit of Thompson's WaterSeal, or any other sealer on the crack. If either seal stains the porcelain, forget it. Repeat this once a day until the leak stops. Second, apply Goop — sold in hardware stores — on the crack and press it in with your fingers. Do the back of the basin, too, if you can reach it. If the Goop is colored, forget that, too.

Q: I have a wood-framed single-glazed picture window with a separate storm window attached. Moisture appeared between the windows, so I took off the storm, cleaned both windows and put the storm back, caulking it thoroughly. The moisture returned. What can I do?

I do have two weep holes at the bottom of the storm frame.

A: Trying to seal the space between windows is like shoveling sand against the tide, and since you failed twice, it is time to stop.

Try this: Take off all the caulking so you have a good wood lip to put the storm window in place. Keep the weep holes at the bottom of the storm frame, and add two more at the top. This may increase air circulation and will allow water vapor to escape, and might end the moisture problem.

A final idea: Put that storm window on the inside.

Q: One of my rug pads is made from recycled tennis shoes that were made into a multicolored rubbery pad. When I went to move the rug and pad, I found bits of rubber sticking to the hardwood floor. How can I get that rubbery stuff off without messing up the floor?

A: Try scraping with a wood or plastic spatula. Or, more effective, wet the rubber with paint thinner, then scrape it off.

Peter Hotton has been The Boston Globe's "Handyman on Call"

for 30 years. E-mail questions to photton@globe.com. Sorry, no personal replies.