Step-by-Step Instructions and Pictures: How to Use a Trim Nailer Gun

End Splitting: Place Nails Accurately
Problem: Split Trim at the Ends
Solution: Nail Farther From End

Driving nails with these tools is so simple that it’s easy to get carried away and put nails where they don’t belong. (Ask any painter who has to putty all the extra holes!) With practice, you’ll get a feel for where the nail comes out of the gun and be able to drive a nail precisely. Photo 3 shows the result of placing a nail too close to the end of a molding. The same thing will happen if you nail too close to the end of a baseboard, especially on short pieces. Make sure to keep nails a few inches from the end of moldings to avoid splitting the wood. Brad nailers, which drive thinner and shorter nails, are the exception. With these, you can usually nail within 1/2 in. of ends and 1/8 in. of edges without splitting the wood.