How Do You Rip Your Balsa? By James Goss      What method do you use to rip balsa stock? Any time you scratch build a plane you can't get around having to rip balsa. Well you can if you buy all the little narrow pieces from the hobby shop, but you can rip them yourself and save money in the process. A band saw or small circular saw is good for this job and a lot of modelers use them for that purpose.  I never use a band saw to rip stock up to one inch thick instead I prefer the knife. A knife will give you a clean rip and without all that saw dust to breath. Balsa dust is so fine compared to other types of sawdust and will get into your lungs before you know it. It can't be good for your respiration system. Even with a mask it is hard to keep the dust out. Working with balsa just about every day now I have found it to be quite irritating to my eyes as well. So using the knife to rip balsa is the tool of my choice.      The problem with using a knife to rip balsa is trying to keep your straight edge from moving during a cut, especially when trying to rip a very narrow piece of balsa. Using a very thin straight edge will allow you to tape it to the balsa. I always use a 2-inch wide 48-inch long flexible metal straight edge and use masking tape to tape it to the work on the backside. The tape will not allow it to move as the knife follows the grain down the length of the balsa. This works great until you get down to a narrow piece of balsa such as a 1 inch wide or less. With wood this narrow you can't tape the straight edge to the balsa anymore because the wood is narrower than the straight edge and the knife blade will follow the grain and veer or swerve off the straight heading.  This has aggravated me for years and I have finally solved this problem. This is how you need to modify your straight edge to make it the perfect ripping tool. Remember you are using a 2-inch wide, about 20-gauge sheet metal, straight edge. Being 2 inches wide will give you plenty of room for holding as well as taping it in place. If you drill four equally spaced holes about ¼ inch from the edge of the straight edge you can then place pins through the straight edge and into the wood. The pins will not allow the wood to move and you will have a nice straight rip. The holes need to be the exact size of your t-pins so there is no play or movement between the holes and the pins. This is so simple why didn't I think of it sooner?      The pins will hold even in a piece of 1/16 balsa, it doesn't take much to keep everything in place. Of course the thicker the balsa the better the pins will hold. As the balsa gets thicker you will need to keep your knife at a 90-degree angle to the board to prevent a tapered cut. I rip up to 1- inch balsa by making the first cut very shallow just to mark the wanted cut line. Each pass go a little deeper, don't try to cut thick balsa on the first pass or your knife will have a mind of its own. This method is fast as well as neat and will give you a professional cut.      You may not have thought about it but a ¼ inch sheet of balsa cost about $1.63 for a 4-inch wide, 36 inch long piece. By cutting it with a knife you can get 16 each ¼ inch square sticks from it. A ¼ square balsa, 36 inches long will cost about 25 cents. 16 will cost $4. You are saving $2.37. If you cut it with a saw you would not get 16 pieces because of the saw blade width. The blade will take up about two sticks in sawdust. So ripping your own stock you will save about $10 on an average kit. Maybe you had rather pay the $10 than to bother with ripping the stock, sometimes I do just that. But there is always that time when you need that special size cut and you need it today and not next week. This is when ripping your own balsa really pays off. I have seen times when I would have paid ten times the price for a piece of balsa if I could have gotten my hands on some.      Being able to rip in a good straight line is also necessary when you are sheeting your model. How many times do you receive balsa sheets that have true edges? Before you can join the sheets together you must cut true edges because of the warps and bows that comes in the sheets. This technique works great for this application also. Remember if you don't true up the edges of the sheeting before gluing them together you will have to force then and this will always result in a crooked sheet.