The new improved shaft is a Metric Steel Grade 10.9 Hex Head Bolt 10mm x 150mm. I had considered using the standard Steel Grade 8.

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1 My edger is a Golden Boy Model KS-1505 MF. This edger was given to me in 1998 by a neighbor. This edger gifted to me was very used, it reminded me of the Golden Boy edger from when I was a young boy and so I was very interested and appreciated this gift from my neighbor. As luck would have the engine is still in very good condition with good compression, just the carburetor needed a good cleaning, the engine runs great. Okay, it was in good mechanical condition except for the shaft was very well worn, the typical wear we all see and are familiar with on the blade shaft of Golden Boy edgers; wearing at the set screw notch where the blade wears the D mount and threads, and the blade could never be reliably tightened to the shaft. Back in 1998 the shaft was very easy to get, it was the common edger shaft part number or 1249 or also the , depending on the part supplier. Even back then I realized the shaft was a poor design only relying on the single pulley set screw for power transfer to the shaft and blade (we had the same reoccurring worn shaft problems on the Golden Boy edger when I was a young boy). Yet the poor shaft was inexpensive and easy to get so we just kept replacing it with the same poor shaft. In 2011 I discovered the edger shaft would no longer be available and that was when I designed a new improved edger shaft for my Golden Boy edger. This is a new improved edger shaft design, the blade tightens reliably to this new improved shaft and it will not wear out like the original poor design at the set screw notch and D shaft threads. Best this new improved shaft is very cost effective and easy to get, and you'll never have to replace the shaft again. This is easy to do and does not take very long (it has taken me longer to post this message than it did to install the new improved shaft), still You must have some small amount of mechanical ability and technical understanding (something, no-doubt, you already have if you are maintaining a vintage Golden Boy edger). On Model KS-1505 MF the edger shaft overall length is 5-5/16" (134.93mm) with 2-13/16" (71.44mm) space between bearing rides and a bearing ride diameter of 25/64" (9.922mm).

2 The new improved shaft is a Metric Steel Grade 10.9 Hex Head Bolt 10mm x 150mm. I had considered using the standard Steel Grade 8.8 bolt (the original shaft was soft steel so this would have worked), but hard Steel Grade 10.9 was available for the size I need so I used the hard Steel Grade 10.9 bolt. If only standard Steel Grade 8.8 bolt is available to you then I am certain this will also work very well.

3 Ream out the pulley to a 10mm hole using a 10mm Tungsten Carbide Double Cut B-Nose, Ball Nosed, or Tree Shape Rotary Burr. I ran the drill in reverse, the pulley shaft steel is very soft steel and the Tungsten Carbide would bite in to much if I ran the drill clockwise. So, I found if I ran the Rotary Burr in reverse (counterclockwise) it did a very good jog reaming out the soft steel pulley. Because the hex head bolt has a very small fillet on the seat of the bolt head I chaffered the pulley very slightly using a pipe reamer. I did this by hand, I did not have to attach the pipe reamer to a brace, I

4 could do it by hand because the pulley steel is very soft. Again I only chaffered the hole very very slightly so the bolt head sits tight to the pulley. This step, I think, could have been skipped. The bolt would have been pulled tight to the pulley when torqued tight. Insert the new Hex Head Bolt shaft in the pulley and tighten the set screw to create a small dimple in the bolt shaft. Then remove the bolt and at the dimple grind a very small notch seat for the set screw.

5 I used a stack of washers for my squash spacer between the bearings. I verified the space using a depth gauge. My squash spacer needs to be more than 2.797in (71.04mm). Stacked 35 washers to make a spacer of 71.75mm. Be observant to keep the orientation of the washers the same, washers are die cut, so they have a face surface and a tail surface. Washers should be stacked all the same way and when compressed they will compress more evenly. To get an accurate measure I compressed the stacked washer in a vise, torqued the vise tight and then measured using my

6 caliper, 35 washers gave me a compressed spacer of 71.75mm. I put all the washers and bearings on the bolt torqued it tight and then taped the washers togther with two pieces 2-3/4" long of clear packing tape. There is also a washer as a spacer between the pulley and the bearing, a washer between the bearing and the fender washer,

7 a washer between the fender washer and the nut. The blade I use is a 2"x9" with 1/2" hole. To keep the blade centered on the shaft I made a center spacer with 14 gauge solid copper wire. To pinch the blade tight to the shaft I use two fender washers

8 I used a Steel Grade 10.9 Nylon Insert Lock Nut 10mm to keep it torqued tight. I also replaced the 6200ZZ bearings. In 2011, the bolt, washers, nut, 10mm rotary burr, and bearings cost me $34 If your Golden Boy edger uses the shorter shaft, part number or 1256 or or or 18692, you will have to figure out your own length bolt and how many washers to stack for your squash spacer. If you cannot find the bolt, washers, and lock nut at your local bolt supply you will find them online at part numbers Hex Head Bolt 10MMx150MMx1.5 Plain MHC B Hardened Flat Washers 10mm Zinc Plated 20mmOD MHFW10 Fender Washers 10MMx30MM 18-8SS MFEN1030S Nylon Insert Lock Nut 10MMx1.5 Zinc Plated MLN1015 If you cannot find the bearings at your local bearing supply you will find them online at or or just search for Bearing 6200ZZ If you cannot find the 10mm Tungsten Carbide Double Cut B-Nose, Ball Nosed, or Tree Shape Rotary Burr at your local industrial supply you can find it online at or just search for 10mm Tungsten Carbide (Ball Nosed) or (Tree Shape) Rotary Burr