At this point I weighed the unlifted door to confirm and fine-tune my calculations. This is not strictly necessary, but it makes the adjustments easier to perform, if you happen to have a scale with the requisite capacity. With some helpers, we first lifted the door a few inches and rested it on blocks of wood to provide clearance underneath. Then I slid a 400-pound-capacity freight scale under the center of the door, we lifted again to remove the blocks, and lowered the door gently onto the scale. This door weighed in at 238 pounds, which is very heavy for a single-car door. Since the outside of the door carries the 3/4-inch plywood paneling to match the house, and that plywood weighs about 2 lbs/sq-ft, I estimate the door weight to be about 7 x 10 x 2 = 140 lbs of paneling with the rest 238 - 140 = 98 lbs the interior panels, hardware, and cobwebs. Knowing this total weight will help later in adjusting the torsion on the springs. After weighing, we removed the scale and blocks, leaving the door fully lowered again. Had I not had a high-capacity freight scale, I might have improvised a crude weighing device from levers and smaller weights of known mass, or a lever arm pressing a reduced proportion of the full weight onto a lower-capacity scale. Another factor to remember is that The weight of a wood door can vary with humidity.
As noted above, set-screw clamping may have distorted the cross-section of the shaft and made it difficult to slide off all the hardware. With the shaft on the floor, it may be possible to restore enough roundness to proceed, using compensating clamping force to the distorted area via a machinist's vise, an arbor press, a hydraulic shop press, etc., on the shaft body. Burrs and other slight distortions on the shaft can be filed off with a hand file or touched with an abrasive wheel on an angle grinder. At some point, the condition of the shaft may just be degraded enough that it ought to be replaced.
Clopay, a garage door manufacturer, provides online installation manuals for their products. These include excellent mechanical diagrams and brief instructions for winding torsion springs on their doors. Of course, this is specific to their product designs, which may or may not match what you have. Note that some of their products involve the "EZ-Set assembly option" mechanisms that use a geared housing for winding (instead of standard winding cones) and non-standard geometry for the drums. Clopay should get an award for at least acknowledging in their instructions that you might be able to install your own new door (although they insist you must not take out an old one if it has torsion springs).
Because your garage door can be customized, pricing varies. Our Clopay configurator will help you review pricing as you begin your project. You’ll start with your door size and whether you need a single or double car door. Next, you can choose the collection of door, which gives you options of various materials and styles. Then, you’ll choose your construction, which allows you to decide what you need in terms of energy efficiency, durability and noise control. Lastly, you will be able to visualize the design and see an end price. Other optional add-ons include windows, decorative hardware, smart features and the r-value. However, you do not have to use the configurator. We also install standard garage doors that have not been customized so you know the product price early on in the process. 

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