06-21-2012, 09:37 PM
It's time to move on to the lever. After squaring up the stock, I drilled the two holes, cut the internal radii with a boring bar and milled an angled surface while it was held in the vise. Next, I set up the 1 1/2º per side taper to the lever with a sine bar and milled them tangent to the two radii that I previously bored. Next, it'll be back to the rotary table for a couple of external radii and then a bunch of hand filing to get the elliptical shape of the lever. I could make another radius cutter, but for this part it would take less time just to file the shape.
Mistake #1 is under the bridge. I made a dimensioning error on the lever drawing and then like an idiot, made the lever exactly to print. But, the good thing about working with steel is that all it takes is a little weld to make it right.
To make matters worse, I had to knock off early tonight because I managed to get a chip in my eye. It landed on top of my safety glasses, fell down behind them and then flipped right in my eye. I saw it coming but not quite soon enough. Guess the reflexes aren't what they used to be. Luckily, even though it was steel, it wasn't hot enough to stick but it still irritated the heck out of my eye. Oh well, it wasn't the first time and it probably won't be the last, just one of the hazards of the trade. WEAR THOSE SAFETY GLASSES!
Just a little weld to make it right.
Here the lever is sitting on a sine bar to machine the first tapered side of the lever. I did one side first, then doubled the angle on the sine bar and did the flip side after sawing off the excess stock.
Next, the sides will be tapered on the belt sander, the end radiused and the elliptical shape filed.
The rough shaping on the lever was done with the belt sander, files and strips of emery cloth.
The rest of the radii were cut on the rotary table (getting rid of the weld evidence ). At the same time, the curved shape around the pivot point was approximated by using three different tapered end mills on the rotary table.
This is a quick and dirty fixture I made up to bend the scroll shape on the lever.
The first curve was tough. It took a lot more heat than I expected due to the thickness of the part and the tightness of the bend.
Making the bend around the second and third form rolls.
It still needs some hand finishing, but I couldn't wait to try it on the gun. The shape is pretty close, but it still needs to be tweaked a bit. Next time I'll add more form rolls to make it easier to hold the shape. Not too bad for the first try though.
Mistake #1 is under the bridge. I made a dimensioning error on the lever drawing and then like an idiot, made the lever exactly to print. But, the good thing about working with steel is that all it takes is a little weld to make it right.
To make matters worse, I had to knock off early tonight because I managed to get a chip in my eye. It landed on top of my safety glasses, fell down behind them and then flipped right in my eye. I saw it coming but not quite soon enough. Guess the reflexes aren't what they used to be. Luckily, even though it was steel, it wasn't hot enough to stick but it still irritated the heck out of my eye. Oh well, it wasn't the first time and it probably won't be the last, just one of the hazards of the trade. WEAR THOSE SAFETY GLASSES!
Just a little weld to make it right.
Here the lever is sitting on a sine bar to machine the first tapered side of the lever. I did one side first, then doubled the angle on the sine bar and did the flip side after sawing off the excess stock.
Next, the sides will be tapered on the belt sander, the end radiused and the elliptical shape filed.
The rough shaping on the lever was done with the belt sander, files and strips of emery cloth.
The rest of the radii were cut on the rotary table (getting rid of the weld evidence ). At the same time, the curved shape around the pivot point was approximated by using three different tapered end mills on the rotary table.
This is a quick and dirty fixture I made up to bend the scroll shape on the lever.
The first curve was tough. It took a lot more heat than I expected due to the thickness of the part and the tightness of the bend.
Making the bend around the second and third form rolls.
It still needs some hand finishing, but I couldn't wait to try it on the gun. The shape is pretty close, but it still needs to be tweaked a bit. Next time I'll add more form rolls to make it easier to hold the shape. Not too bad for the first try though.