Swingarm Pivot, pt 2

Sunday was a good day. I made a lot of progress on the swingarm pivot. It is nearly done:

Getting started on the nut. 1.5" hex stock. I need to bore this and machine a .800"-20 thread.

If you look at many large nuts, you'll see a relief cut around the inner face. I made the relief .015".

After one face of the nut is cut, it needs to be cut to rough length and the opposite face machined. When doing short parts like this, it helps to place two parallels behind it when you put it in the chuck. This will ensure that the part is held square. Remember to remove the parallels!

If you want to do a lot of machining, you have to learn to get comfortable working close to the chuck.

The bore for the thread is .750". Thank goodness! A nice standard size. Anyway, my 3/4" drill needed a touch up. I've had my Drill Doctor for several years now, and it has paid for itself a couple of times.

Drilling operation being completed.

Square up the tool bit.

Cutting an internal thread means rotating the compound to the opposite side. It looks awkward, but it does the job.

Taking that first cut. Fingers crossed. This is, in fact, the first time I've had to single point an internal thread. It's tricky, but I've got the hang of it now. Previously, when I've machined nuts, I've been able to use taps. I knew this day would come.

Since I didn't have the forethought to make a thread gage for this thread, I had to use the shaft. Carefully back the compound slide off, and check. These threads are a go!

New on the left, old on the right.

It's time to step up the holes in the quadrants.

With most of the holes done, I added two new bolts, then removed the ones that had held them together before. The final holes could then be cut.

On the left, an old quadrant. Bottom is a finished quadrant, top is in progress.

Using a v-block to ensure the quadrant is welded square.

Bam! All that's left to do is cut the thrust washer and enlarge the hole in the free quadrant.

Mine definitely looks better!

Stay tuned, we'll wrap it all up in Part 3.