Thread: Pictures from my shop

Made up a fixture using some Mitee Bites, still early in the game but they seem to be working pretty good. Need to do some tweeking to make loading and un-loading a little better.

Are you using PHT 4340 or another material?

Originally Posted by Perry Harrington

Are you using PHT 4340 or another material?

4340 heat treated to about 40rc, blanks are are heat treated and then machined. Tried it the other way around and had parts come back from heat treat with what appeared to be de lamination, or cracks. Nothing like getting a ton of work in something only to have it come back from heat treat scrap.

First time using the steady rest on the mill. Had to rough out some cams before going out to HT and grind. I know its a cobbled up set up, but I only had 5 parts to do.

I have built supports just out of a V'd block of brass before, but never "captured" one in a steady like that before.
Interesting!

Dare I ask what kind of tooling/opp you are using in a mill to rough those in?
Just a lot of 3D work, or ???


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Think Snow Eh!
Ox

Clint,
Looks fine to me. Is that 8620?

yep, 8620
3/8 ball mill, cam profile wrapped around the A axis, so the Z and the A move in sync to create the lobe, .01 to .02 step over in X. Worst part was diggin through the machine parameters to figure out how to avoid un winding the damm rotary.

Originally Posted by cpifer3

yep, 8620
3/8 ball mill, cam profile wrapped around the A axis, so the Z and the A move in sync to create the lobe, .01 to .02 step over in X. Worst part was diggin through the machine parameters to figure out how to avoid un winding the damm rotary.

HAAS has a video on You tube about how to quickly unwind the A axis. Nice work well done.

Make Chips Boys !

Ron

Originally Posted by cpifer3

yep, 8620
3/8 ball mill, cam profile wrapped around the A axis, so the Z and the A move in sync to create the lobe, .01 to .02 step over in X. Worst part was diggin through the machine parameters to figure out how to avoid un winding the damm rotary.

If using a ball @ 12 O'clock in Z/A (with X step-over), wouldn't it be more better to just use a reg mill @ 9 O'Clock and use Y/A in stead?
That should acomplish the same thing, but would be working with a much better part of the tool geometry.

Should save tooling and likely be able to greatly increase feedrates? (I would like to think trippple at least?)

I have no clue what would be involved in updateing the code tho....

???


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Think Snow Eh!
Ox

Never thought of trying it that way. Would probably work good depending on the profile of the cam.

There's a lot of nice work in this thread! I'm originally from Nova and went to elementary school in Polk. I had no idea someone with your capabilities was in the area.

Originally Posted by Ox

If using a ball @ 12 O'clock in Z/A (with X step-over), wouldn't it be more better to just use a reg mill @ 9 O'Clock and use Y/A in stead?
That should acomplish the same thing, but would be working with a much better part of the tool geometry.

Should save tooling and likely be able to greatly increase feedrates? (I would like to think trippple at least?)

I have no clue what would be involved in updateing the code tho....

???


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Think Snow Eh!
Ox

Standard end mill with a corner radius with the edge at 12 O'clock. You could use the same program by adjusting the fixture offset by the radius of the end mill. I've never done metal this way but have done a lot of plastic cutting big grooves.

So did you use a CMM to copy an original profile to make these? I have a rare set of camshafts that no company wants to do unless "I" collect all the data myself on the rocker arm geometry etc etc. I offered to send the camshafts AND heads to them to get the info for an original set, then I wanted them to modify them by X amount. Nope. Really aggravating as a machinist ya know.

Originally Posted by EndlessWaltz

So did you use a CMM to copy an original profile to make these? I have a rare set of camshafts that no company wants to do unless "I" collect all the data myself on the rocker arm geometry etc etc. I offered to send the camshafts AND heads to them to get the info for an original set, then I wanted them to modify them by X amount. Nope. Really aggravating as a machinist ya know.

So get your degree wheel and dial indicator out and get the data.

I bought a digital mitutoyo indicator with the intent of measuring camshafts. The idea was to motorize a rotary table and have a computer digitize the camshaft. Motor spins rotary table and then it reads the output of the indicator.

I could think of a couple other ideas:

attach a rotary encoder to a camshaft and read both the rotary encoder and indicator, when the encoder changes count, record the indicator position.

You could also connect a stepper motor to the end of the cam and rotate it through N counts while reading the indicator, where N is the counts per rev of the stepper.

Going even more low budget, you could use an old ball mouse as an encoder and read the mouse position while reading the indicator, the ball would travel around one of the journals (with some masking tape on the journal to provide grip).

If you wanted to do it with just a single mouse, you could take one of the encoder axes out of the mouse and put it on an arm that simply follows the cam lobe, while the other axis records rotation.

Copying an old cam profile onto a new blank is probably the only thing I can think of that one of those ancient true-trace Bridgeports might be useful for.

There used to be a tool called the "Cam Doctor" which would measure cam profiles. A quick google search shows this company is no longer in business, but there are others available now.

Originally Posted by DrHook

There used to be a tool called the "Cam Doctor" which would measure cam profiles. A quick google search shows this company is no longer in business, but there are others available now.

Its called a cam pro and it is pretty much exactly what Perry described. Encoder on the end of the cam and dial indicator with correct size roller. Enter all your parameters (rocker ratio, tappet type,etc), zero out on base circle, rotate 360, computer software does all the work for you.
Or, like moonlight suggested, degree wheel and dial indicator.