Side Milling

[dicej32]

I'm having a tough time getting a decent finish when side milling. By this I mean when you take say a 3"x3"x.25" aluminum plate and set it in the vise flat. You then use your x axis to move the stock sideways against the side of the mill bit. I always end up with a ridged finish. If i set the stock vertically on it's side and use the end of the mill, the finish is smooth and shiny. Any recommendations?

Thanks,

Jenaro

 

[rake60]

Jenaro
There are several possible issues that can cause a poor finish when milling with the side of an end mill.
The biggest is the direction of feed. I prefer "climb milling" myself. That would be feeding the stock into the
cutter contact side rotating in the same direction as the direction of feed.

Here's a link to a page with better information. Union Butterfield End Mill Applications

Rick

 

[wareagle]

Right, wrong, or indifferent, this is what I do when side milling. I will mill the edge with the cutter going in both directions; in other words I cut on each direction of travel. Be conservative with the amount of cut when climb millling. When I get close to my intended measurement (or just a smooth edge), I will then take a few thousandths off by climb milling as Rake has described. This typically yelds a smooth finish.

One thing I have noticed that really makes a difference for me is the speed and feed. I have to admit that I am one that doesn't figure optimum speeds and feeds for each cut, but then again I am not building parts for the Space Shuttle, either. But this is one instance that it really makes a better finish for me.

The cutter has made differences for me as well. I have both chi-com and US made cutters, and for side milling edges where the finish counts, I will use the US made cutters as they have produced better results for me. This may be dumb luck, but it has seemed to remain a constant in my shop for this operation.

 

[shred]

Assuming you aren't using a roughing end mill , note that an end mill bends a little bit on side-cuts, whereas on end-cuts, it doesn't.

 

[PolskiFran]

Try taking a "zero cut" otherwise known as a spring pass. I usually do this after my finish dimension is reached to get a better finish. Usually in climb mill mode. It will usually only remove a tenth of a thousandth or two.

Hope this helps,
Frank

 

[dicej32]

Thanks for the suggestions. I'll try the very light finishing touch in the climb direction. Also I'm going to try snugging up the gibs.

Jenaro