If you need to replace a baluster on your staircase, you may want to contact someone who offers CNC machining to help you. Before doing that, there are a few elements you may want to consider.
1. Consider Bringing Another Baluster to the CNC Machinist
If you are replacing an extremely detailed baluster, you may want to bring one of the intact balusters to the CNC machinist. Then, they can create a model so that they can make the new baluster accurately. Working without a plan is nearly impossible.
2. Take a Lot of Measurements
In some cases, it may be impossible to remove the existing balusters. In these situations, you may want to bring the machinist to your home so they can look at the balusters to get an idea of what to do. Alternatively, you may want to snap photos of the other balusters and bring measurements to the CNC shop.
Measure the height of the baluster, and also measure the circumference of each different area of the baluster. If parts of the baluster taper in at the edges and bulge out at the middle, measure the circumference at the most narrow and widest parts as well as the height of these areas. The machinist will put that information into the CNC machinery to guide them as they work.
3. Consider Putting in New Balusters
If you cannot find a CNC machinist to make the new balusters for you, you may just want to opt for all-new balusters. You can buy new ones or have them created. This ensures that everything looks the same from a design perspective. So that the balusters match the railing, you should take photos of the railing and give them to your machinist.
4. Look Into Inserts
Alternatively, instead of making new balusters, you may just want to opt for a railing insert. This is a large piece of metal or potentially wood that fits between the top of your railing and the floor. It can have many different designs.
For example, you can go with a geometric design, or you can opt for something that incorporates a lot of wildlife. There are sites where you can download plans for CNC railing inserts, or your machinist may have some options and ideas on hand. Although these inserts have different designs, they are still made with building codes in mind and they don't feature large gaps that toddlers could slip through.