Hey All,
Pic is the top view of 4" x .5" thick alu. (may need some of 1018 steel also)
The parts are identical, just rotated to save material. (I'm Scotish.... ish  .)
I thought about drawing the basic profile in 2 layers. One to cut the majority (blue), and another to cut it off (Yellow).
I imagine a .250 endmill, several passes.
How would this normally be done in the real world.

Thanks

Does those parts needs holes.

If yes, I would drill the holes first and bolt the part on a setup plate.

Also depend how many you have to do.

Will not be the same setup for 4 parts as it would be for a thousand parts.

You could leave some tabs to keep the part in place and avoid breaking your end mill or damage the part.

Is the distance from part to part in the X direction is the same as your end mill diameter.

Jeff

 

First, I would have to ask what level of accuracy your wanting. If their for "farmer Joe" to weld up on his tractor equipment, I would just hang 'em off the end of the vise, cut the profile as best I could, knock 'em up against the belt sander and send them on their way. Otherwise, I personally would not do them all in one big stretch like you have them laid out. If you think along the lines of "2 parts per setup" then you will still maximize the material usage, as indicated by the green vertical line in the pic. Like Ostie said, if it has holes, (more than one, preferably) that's really an advantage, and is going to be your easiest method. Just bolt it to a setup plate using the holes, and then you can cut around the entire profile. Sometimes, I have drilled the holes smaller than required, in order to make a closer fit around the bolt(s), or even ream them for shoulder bolts, and then after the profile is cut, go back and drill the holes to the required diameter. If it does not have holes, I would cut the plates along the vertical green line in the saw, leaving yourself a small bit of extra length for the next operation. Next, put one part in the vise, and square up one of the ends with an end mill. Flip part, square up the opposite end. Rinse and repeat for all the parts. Next, I would discard the vise, or move your operation to the side of the vise, and cut the profiling operation on the milling table. First, find a sacrificial plate, so you can cut the entire depth of the part, without ruining your table. Then square up the part along the table, by using the end you previously squared up as your guide, and hold down the part using a toe clamp or similar. Use an edge finder to get your X zero point. Looks like you have some extra meat in Y, so you might get by without the edge finding in Y, using a guesstimate. Cut along your blue and yellow lines. Flip part around, repeat.
Obviously, "the devil is in the details" as they say, and methods will vary greatly. Everybody has different tools and machinery at their disposal(or lack thereof), along with personal methods.

Hi guys,
Jeff, there is one hole, cant add another so I figured it wold not be any good for holding, just locating maybe.
I do about 30 pcs each run.
I also thought about tabbing but would like to eliminate the clean-up afterwards.
I can space them in X as necessary to allow a finish pass at full depth for a good finish.

I like the idea of "pairs" Sam, that looks to be the simplest and is what I will plan on using for now, THANKS !
There is a little extra material in the Y so that makes it easier as you say.
This is not a super critical part as far as the profile goes, they are part of a weldment.  But I would like for them to be within +/- .005"

Thanks again men,
Rc

What is the hole size? If it's big enough to put a substantial bolt in it (like 1/4"), then you're good. Bolt the stock down to a sacrificial plate (use enough for a pair like Sam suggested - you will have two bolts holding the stock), using the holes, then mill the profile leaving about 0.01" for the last pass - it is enough to hold the stock, but yet not to much to develop large cutting forces on the last pass, so the single bolt per part should handle it fine. Just tighten it firmly.

Dan

Another good idea, thanks Dan.
That would let me cycle 2 parts per set-up.
I like it.

And, you wouldn't have to mill the ends square after you cut the stock, since you can cut the entire profile, so that's also a step deleted.

you have one long straight edge on the part. Align it to a finished edge of the material so it does not have to be cut then clamp each part from that edge and then push the button and cut as many as you can line up at one time. IF material waste is a concern then alternate the part to the upper and lower edges

Just a thought, (;-) TP

Hi T,
 The part is 3.8" by 4.1"    The material is 4"
The long straight edge cant be used as the part would not fit the material if rotated 90 deg.
The only common straight surface is the small one at the bottom of the 1st part, which is too small for a hold-down.
Also, the "ear" at the top is actually a radius, same rad. pt. as the hole.
If I had wider material, your method would be perfect ! Just trying to use the matl. that I have on hand.
Thanks Terry

lay the part down so the long angled line lines up with the bottom of the material, then rotate the next part so the angled line uses the top. That gives you a clamping spot that does not have to be machined.

Looks like it would work from here.

Do you have a dxf of the part, I will lay it out here to see if it fits.

Just a thought, (;-) TP