Building a Cam

UPDATE

Cut part of the plate today and began milling it to the correct thickness. Was able to Finish that and cut the plate into three parts to begin making lobes. The fourth part was messed up a bit by a loose milling bit, so I experimented with it and the band saw to see how well cutting the lobes would work. It turned out fairly nice and I might finish it to make a keychain ring or something....

Messed up section that I practiced cutting lobes on.

Finished milled plate with lobe for sizing

Side view of milled plate

Love the can of TapMagic in the background. That said, kerosene or WD40 works better as a cutting lubricant for 6061 aluminum unless you pony up for the special "aluminum" TapMagic.

I've gone through pretty much all of my archives and it looks like I no longer have a copy of the article I wrote for RC on making a cam with nothing more than a hacksaw, drill and a file (see post above). IIRC the drawings I provided was for a cam that was ~#3 C4 sized, cost $35 in materials and failed at 22kN, but damned if I can find a copy of it. The SolidWorks models I used for the graphics are likely still floating around somewhere, but probably wouldn't do you much good.

Very cool. I have zero metal working experience but am intrigued by your project. Cant wait to see how it come out. Looks like you have lots of sage advice around MP.

Keep up the good work it's looking good.

That Cam Building Comp was so much fun (I made the big WebCam), I was pissed when it didn't go the next year but what can you do.

Sounds scary be carefully man.

Looking 'bitchin' good so far.

Aric Datesman wrote: Oops! There was a good bit of behind-the-scenes unpleasantness with the 2010 comp and I apparently did too good a job forgetting everything about it. Sorry!

I'm just messing with you Aric, no worries.

Really cool project Kevin, looking forward to seeing more progress.

You said this is for school, might be good to spell axle correctly for anything written and submitted for your project.

That is cool! Looks like an old rigid friend.

this has to be the best thread (polite, interesting, and progress) on MP!

UPDATE:

Spent yesterday and today cutting out and finishing lobes. Ready to begin cutting holes for axle and lightening holes. Can't find a drillbit that works though, so I might have to use a smaller size one and file out the inside until the lobes are loose on the axle. Ben Hicks- luckily this is the one class that requires zero writing, although thanks for pointing that out. Ben Beard- Thanks! I am really enjoying working on this project and hope to finish in the next week or so. The feedback I have received from everyone on MP has been great.

All four machined lobes next to the G4R template lobe

frekin awesome way cooler than the gun cabinet i made in high school!!

UPDATE:

After messing up another lobe (lesson learned, go slow) I milled another and got it cut today. After that and a bit of searching, I found a drill bit slightly larger than the axle, and drilled the holes for the lobes to fit on the axle. Tomorrow I plan on working on trigger wire holes and holes for the pin that will hold the spring on.

Side view of lobes with stem

Top view of just lobes

Top view of lobes and stem

Dude, good on'ya. I would have been trying to find a way to smoke out of it in HS.

jake 356 wrote:frekin awesome way cooler than the gun cabinet i made in high school!!

gun cabinet? shit, we were stuck with making a metal ash tray(before political correctness days).

In the 70's when guys were first admitted to 'home economics' classes like sewing, the Frostline Kits company kept many an outdoor guy busy designing and sewing up either a down vest or jacket, or a sleeping bag in high school. That was worh the project for sure.

UPDATE:

Getting close, got the cam stops/spring pins installed in the lobes today. Just have to add lightening and trigger wire holes and finish the trigger bar them I'm basically done.

The lobes with cam stops/spring pins

Another shot of just the lobes

The stem with the lobes attached to check fit

Another shot of the stem with lobes

This is an awesome project dude, looks like a ton of fun! I am curious though, could you not have gotten a piece of aluminum closer in width to the lobes instead of having to mill off what looks like almost half of a thicker piece?

pm sent on buying the cam...

Nice work!

Let me know when you start making new offset Alien clones.

This is about the coolest thing I have seen in a while!

When you move on for your engineering degree it will be fun to do some load testing on this in your Mechanics of Materials class...