Sine of 45
I know most of my readers like action shots. Here are a few to keep the juices flowing. It’s just one very tiny step in the making of parts, but there is a bit of interesting machine set up going on here.
I had to cut a 3/32″ wide x 45 deg. chamfer on the one end of both of the two brackets I made for the tender steps. That doesn’t sound like much of a job, does it?
I priced 45 degree end mills and after I got back off the floor, I decided that wasn’t the least expensive way to run this job. At least for the two tiny cuts I needed to make. A file might work but it would look like… well you know, the smelly stuff.
I dusted off the sine vise and although it seemed like massive overkill, it wasn’t all that hard to set up. The fun part was I was able to do a little math and I actually like math. The reason it is called a sine vice is the height of the spacers (called sine blocks) is the sine of the angle desired times the distance away from the hinge.
Here I wanted 45 degrees, and the sine of 45 is sin(degrees(45)) = 0.70710678. I used o.707 as close enough. I have a 4 inch sine vice so the stack of blocks needs to be 0.707 x 4 = 2.828 inches. You can see that number on the top of the pink notepad in one picture. I rounded to 2.830 just to make it easier to build the stack and still be plenty (over) accurate for this task.
Two 1.000 inch, one .700 inch, and one .130 inch block does the job. The actual machining seemed trivial as it usually does. 🙂
Another Project Finished
Yes-sir, completely scratch built from raw ore. NO, not likely. Ha!
This is a little repair project my daughter gave me. It is a ball head for a camera (photography) mount. The bottom of this device screws down on a tripod or studio steady mount.
There is a quick release on the top that is attached to the camera.
The handle bolt is loosened to adjust the angle of the camera and that is where the problem was. There are internal splines in the original handle that were stripped out. It would no longer turn the locking bolt to secure the ball from moving.
I learned all about these spring loaded handles and also how the ball mount itself works in this little project. There are two main types of these handles. Most of us know the “pull the handle to adjust position” type. I have a lot of them on my machine tools. There is a second type called the “Safety” handle where the user must push in against the spring load to engage the handle. That is what I have here. The handle pops back out and drops to a safe position when not engaged.
So the project was mostly selecting the correct replacement handle. However there was a catch. There is always a catch, right? The end of the original bolt was drilled out and a pin with a tapered cone inserted. It is this cone against an internal ramped surface that pushes up and locks the ball movement.
The machining chore was to drill out the end of the new handle bolt to fit this tapered cone pin. The challenge was to hold the bolt for drilling (without disassembling the handle) and drilling the hard end of the bolt deep enough for the pin to insert.… Continue reading
It’s The Little Things
The small bits and pieces are going to get me. All home machinists know the purchase of the major machines is the big money decision in getting started. No doubt about that. But there is something more insidious to my available funds.
What gets me after the big purchase is the constant cash flow required in getting all the little bits and pieces I need to get projects completed. It’s not really any different than any other hobby. All my other hobbies I enjoy seem to be cash eaters too. Maybe I should take up whitlin’ if I can find some free wood.
I was just sitting here at the computer ordering a few restock parts from McMaster-Carr. I am updating my starter and countersink drill bits both 60 degree and 82 degree. They generally last a long time but mine have seen better days. I’m getting a five piece set of each angle. I need a couple of #2-56 taps, two because I’ll break the first one. With two I won’t break either. That’s the way it works, I know.
OK, throw in some #2-56 flat head machine screws, only a few bucks…
What happened? (!!) That total can’t be +$80.00! Wow, its right. My theory is correct. It’s the little things that bite me the hardest.
Back Breaking Work
I made one part (#10) two pieces last weekend. I milled a 1/2″ square bar of brass into a 1/8″ x 1/2″ angle. It is to be used for the brackets to hold the tender steps. I got the milling done just fine. Then…
I reached around the X3 mill, I think to turn off the main power. It felt like I got stabbed in the back. I have a bad vertebra at the bottom of my spine. Years of heavy lifting destroyed the padding. Occasionally I get an extreme pain spasm and this was one of them.
That shut me down for the rest of the weekend in the shop. ($#^$&#^) <– swear word
I didn’t even get the holes drilled but I did get it cut into two parts. That’s not the correct location in the picture. I just posed the parts…
An immediate heat pad and some ibuprofen got me healed and back to work today. This was one of my shortest episodes. I’ll have to hit the heat pad quickly again next time. Also, I didn’t keep pushing it. It’s heck to get old. I wonder when I will get there?
I’ll just claim working on scale steam locomotives is back breaking work…
Lens Plate
My daughter is a professional photographer working for a large commercial corporation. Some of the studio cameras use lenses that mount on a lens board as you see here. That is not a real piece of board, but rather a cast aluminum plate. I think the idea is to make lens changes and adjustments easier.
On this one someone bought the lens board with a hole that was too small. Maybe they got a deal? You can always make a hole bigger right? Problem is most people do not know how to make the hole bigger. If they know, they probably don’t have the proper tool.
I was given another lens board with the hole being much larger than necessary. “Just make the small hole half way bigger than the large hole.” I was told. I love those accurate working dimensions. Ha!
It was dang close to being a 2 inch hole I suspected I needed. I bored the small one out to about 1.995 inches. I was actually thinking 2 inch but short is better than taking too much.
My daughter took the lens board to work and sure enough the hole was still too small. “It needs just a hair more, Dad!” was her request. Uh… “What color hair, kinky, curly or straight?” I went for red, curly.
In the pix I went out to 2.010, so I’ll see if I got the color right…