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  • Home
  • About/Contact
  • Projects
    • Rocket Fin Jig
  • My Workshop
    • Organization
    • Mill Workbench
    • Notebooks
  • The Mitch Blog

The Mitch blog

Soldering Station

7/26/2015

1 Comment

 
I recently helped my lovely wife install a new radio into her car. Taking the old radio out involves some brute force and ignorance, greatly aided by the Master Sheet that Crutchfield emails along with the radio. For some reason, every OEM radio I've seen has an extra screw that serves only to complicate removal. I'd say this is an anti-theft feature, but who steals the crappy stock radio?

The most fun part of installing a new radio is soldering the new radio's plug to the adapter that comes with the install kit. The radio manual helpfully suggests splicing into the car's wiring harness, which is insane.

What makes soldering such a pain is having to dig out the soldering iron, and solder (stored in different places, of course) and then find a flat surface to do the soldering.
I took a scrap piece of MDF board (from a super nice knockdown desk) and stuck in a threaded insert, then used a threaded knob to hold on a roll of solder. The actual soldering iron is held stationary using a bunch of wood screws and some zip ties. We'll see how well the zip ties last, but if they're good enough for auto repair they should be dandy in a silly solder board. The final touch is a scrap piece of plywood and part of a paint stir stick to keep the cords from flopping around getting broken.
I still need to add a helping hand and maybe a spot for shrink tubing.
Picture
Picture
1 Comment

Milling a slot in a motorcycle engine

7/19/2015

12 Comments

 
This post is a bit of a blast from the past (March 29, 2014 to be exact).

My brother had a Honda CB-350 motorcycle, which he was in the process of restoring. He got a new timing chain tensioner for the overhead cams, but the original timing chain slot in the engine head wasn't wide enough. That's where I came in. We fixtured the head on the mill, which was very simple, if not very easy.
Picture
Cutting the slot.
The head didn't have an entirely flat surface on the bottom, which is why you can see it's sitting on two clamp straps. I was probably picking up bosses originally in the casting, though I can't remember now. Fortunately the flat surfaces available were parallel to the bottom of the head, or I'd have needed a machinists jack or two. The block did have two very convenient through-holes, which I stuck studs through and then tightened down with nuts, visible immediately to the left and right of the spinning endmill in the picture. The through-holes weren't in an ideal spot though, so I used regular step blocks (a LOT of them, as you can see) to hold down the back end of the block. I didn't need to use any stud couplers though, because clamping studs are always longer than you need for some reason.

The slot started out at .651 wide, and we needed to open it up to .800, to a depth of 1.50.   I also measured the distance from each side of the slot to the combustion chamber dish and found that the slot was .025 closer to the right head. I was using an 11/16 endmill (.691), so I did some math and worked out that I needed to cut .042 into the right side, and .067 into the left side.

I zeroed the X-axis leadscrew, came over .042, widened the slot .800 deep, then locked the X-travel, took up the backlash, rezeroed the leadscrew, and came backward .109 to finish the job. The tensioner fit perfectly, and the bike's running today as far as I know.
Picture
Both photos by Max Thomas
12 Comments

What's in the works

7/19/2015

0 Comments

 
I've got a blog post about an older project in the works, and I'm shooting video on a project right now. Stay tuned.
0 Comments

Hello World!

7/15/2015

1 Comment

 
From what I can tell, the blog functionality is the best way to put things up on the website. To the extent that there is non-blog content on this site, it'll probably all get rolled into blog postings before too long.
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