Pin Top Hardwood Stair Balusters
QUESTION: I can find lots of descriptions for installing balusters for post-to-post systems, but nothing on pin tops. What is the right way to install Pin-top balusters? Before or after the rail is in place?
ANSWER: Pin top installation is actually a simple process. First, the newels and rail must be installed, or it becomes a nightmare to install. With the handrail installed and in place, lay out your balusters on the floor. Plumb up to the bottom of the handrail (I always made a light pencil mark on the side of the rail which can be sanded or rubbed off later), then use a square to find and mark the baluster center. Use a spade/paddle bit. Most pin top balusters turn down to a 5/8", therefore your paddle bit would be 5/8". With the paddle point pressed into your center mark (or you can use a scratch awl and mark the center) you can begin drilling. If the rail is at a pitch you can start the drilling at an angle; once it bites you can straighten the bit and visually align it with a window or door casing to know that you are drilling plumb. You don't have to go more than 1" deep, or to the shoulder of the paddle bit. Set the baluster’s bottom 3/4” into the pre-drilled hole at the floor and hold it plumb to the side of the handrail. Mark the pin about 3/8" to 1/2" above the bottom of the handrail. That would be your cut mark. Once that has been achieved, you can push the pin up into the handrail deep enough to clear the dowel on the floor. Twist the baluster down into place on a small bed of glue around the 3/4" floor hole. You may then use a brad nailer to shoot one nail just below the pin into the handrail. You're done! This usually gives you a full 1/2" dowel into the floor and about 3/8" dowel into the handrail.
QUESTION: Since the baluster cannot be perfectly vertical and therefore misaligned with the hole in the rail when you first insert it in the rail, a tight fit between the top of the the baluster and the hole in the rail is not helpful. Is the nature of the drilling and the characteristics of pin top balusters such that there will automatically be enough slack to insert the baluster, even at an angle initially?
ANSWER: Once the baluster is trimmed, the “misalignment” is not an issue, nor is it difficult, but rather is an easy insert to put the pin into the handrail hole, lifting it up into the 5/8” hole until the turned dowel on the baluster can clear the floor; then the baluster can be twisted down on a bed of glue.
When I was young I was involved in production stair installation for subdivisions or tract homes in Southern California. We were always looking for "ease of install" and "speed", along with a quality finished product. Once I was installing a custom home and I got wind that the carpenters next door were also installing a stair and that they were having severe problems and wanted my advice. They were installing the balusters first and trying to set the handrail down on top of them. They had been at it since early morning and it was now early afternoon and they were not even close to having accomplished anything. I had them install the rail, drill out the holes and trim the balusters as I had described and they actually got the job done within hours.
Regarding paddle bits, if properly sharp, do not make sloppy holes. With hard maple they key is, keep a sharp paddle bit. It will go smooth. Once the holes are drill you can use an orbital sander under the handrail to clean off any burrs before the baluster installation begins.
For the installation, sample your first baluster exactly as I described. If you need to, you can always trim another 1/8" off until you can easily make the insertion. Try and keep 1/4" minimum to 3/8" of pin into the handrail.