CNC Mill Reccomendation

[pauls]

The attached pic is similar to the cnc flanges we make for turbo setups. The problem is they take forever on our industrial hobbies machine. The material is 1/2" CRS. The flanges are 3" x 14" long. Currently using a 1/2" 4 flute carbide mill, cutting pockets and then contour the outside. The max the IH mill will go is .07" depth at 6ipm. Any more the machine shakes or the spindle bogs down. Can take lighter cuts but even with .02 can't get faster than 10 ipm. Its time to get a real mill. We have loads of parts to make. Can anyone give me an idea how I would cut these and approximate time to complete on an entry level Haas or equilvilant. I'm going to visit some dealers in the next month.
Thanks
Paul

[cnczoner]

I believe IMTS is coming up in June. Take a few samples and you'll be overwhelmed with info.

Cheers,
-Neil.

[Ken_Shea]

Paul,
Obviously open to others opinions and arguments, however, Haas is an excellent choice.
For that size material the Mini Mill would be a good choice but with the Z axis extension. More than enough power for steel.

Haas has a wonderfully control, one of the more affordable CNC mills, made in the USA also very popular, consequently, lots of helpful information is available should or when you may need it.

Ken

[9 1/2]

http://http://www.imts.com/

[Geof]

What Ken says .

To compare with your .07" DOC at 6 ipm I do cold rolled or hot rolled at up to 0.20"DOC and 20 ipm using a 5/8" dia. four or five flute cutter, and compared to some people I think I am being conservative.

And, as Ken says also, the Haas control is very friendly.

[DSL PWR]

Without a cad file to go over I'd say it would take about 30 min for one piece on my TM-1. Since it looks like that is a 2 sided piece you could make a fixture for it and get 2 on the table. (1st op on one, and the 2n'd op on the other) So every hour you would have 2 complete flanges. This is with conventional tooling.

I'd run my 3/4" CIEM at 18-20ipm with a .17" doc. @ 3055 rpm. Then I'd go in with the fattest solid carbid mill I had for the finish pass. (providing I had enough room)

Now since you are doing lots of parts It's time to look at a hi feed endmill. I just got a 1.25" hi feed from Ingersol. Most of the time I can double my material removal rate. This sucker goes at 1300rpm (about 420sfm) with a .035" DOC at 100 ipm (this is in 1045). This gives about a .04"/tooth chip load. It seems to work best with up to 70% WOC, and I need to go to .02" DOC if I take a full pass. For your project I'd look at a 1" hi feed cutter (I know Walter makes them).

The problem with the conventional CIEM is the machine just isn't ridgid enough to use all of the hp. I personally an running a Mitsubishi AQX 3/4". This cutter would be able to do your profile in 1 pass with a bigger machine. But on an entry level machine like mine it starts to shake it's self to death, and with the death rattle come's blown inserts. With the hi feed there is still some vibration, but it is tolerable, and I get great cycle times.


So If I were you I'd took at a mini or a TM-1p. For a few grand more on the TM-1p you get pretty much the same machine, with double the y axis. Yes I know it's a little slower, but you don't have the rpm to make use of the speed any way. I'm guessing if you are doing turbo flanges, you may also get some bigger parts in the future. I know the smaller table would kill me, as I typically keep a vice on one side and a chuck on the other. Also remember that even with the 4" riser you will run out of z pretty quick on the mini.

I've had my TM-1 for nearly a year, and for about 6 months I've been cursing myself for not getting the tool changer at the very least, and a better enclosure would also be nice, with a chip auger...

Also remember not to cheap out on tooling when you get the machine, the extra capabilities won't gain you anything with poor tools. Since I've bought my mill I've spent about $15 000 on tooling. I've said it before, and I'll say it again, these tools are more expensive than drugs!

Good Luck

[jalessi]

Have you concidered a water jet, it might be the perfect solution for cutting your exhaust manifold flanges.

Jeff Alessi
jalessi@aol.com

[DSL PWR]

Originally Posted by jalessi Have you concidered a water jet, it might be the perfect solution for cutting your exhaust manifold flanges. Jeff Alessi jalessi@aol.com

The problem with that is these flanges have some extra profiling in them, so he'd still need to mill them.

[Geof]

pauls; I have a question for you. You use 1/2" cold rolled and machine at least one face as well as pockets. Does it distort and if yes by how much? My experience with cold rolled is that if you take say 1/32" to 1/16" off one side of a piece of cold rolled about 14" long at will curl at least 1/32" over its length. Do your flanges do that.

[cnczoner]

IIRC some of the major exhaust header manufacturers in the US will CNC plasma-cut the basic shapes first, then mill them to the final size and features.

[DSL PWR]

Originally Posted by cnczoner IIRC some of the major exhaust header manufacturers in the US will CNC plasma-cut the basic shapes first, then mill them to the final size and features.

This does work, but I hate cutting thru flame cut material. Most of the time it goes ok, but there is always a couple parts where you hit a hard spot, and BANG!!! there goes your inserts, and very shortly after your tool. I nearly cry every time I try friction welding...

[jalessi]

There must be a much faster way to rough out these parts using some technology other than a mill. You guys are the experts!