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Gallery, Projects and General => Gallery => Topic started by: boatmadman on December 07, 2009, 04:33:32 PM

Title: First swarf - at last!
Post by: boatmadman on December 07, 2009, 04:33:32 PM
At last I got to play with me mill, after re organising the workshop and having a dividing wall built!

Anyway, the pic shows a piece of cast iron faced off using an 8mm 4 flute end mill at 1100revs and slow feed. Final cut was 0.02mm

How do I stop producing  the tramlines on the surface?

Ian
Title: Re: First swarf - at last!
Post by: cedge on December 07, 2009, 06:30:19 PM
Ian
Congrats on finally getting to move metal!! The cut lines are pretty normal when using small cutters. The best you can do is tram the mill as close as you can get it. If you want a smoother surface you'll have to use something like a fly cutter or spend some quality time with fine sand paper and a flat surface.

Best
Steve
Title: Re: First swarf - at last!
Post by: AdeV on December 07, 2009, 06:39:58 PM
I agree with Cedge. OK, I'm also a newbie at milling, but if I use the end of an end mill I see exactly the same patterns as you're showing there. My indexable shell mill, however, makes pretty glass-like surfaces.

If you can feel pronounced ridges between each line, then your mill is out of tram in the x-axis (assuming you were cutting in the y-axis, front-to-back & vice versa). John (Bogstandard) posted a C-o-C somewhere explaining the effects of tram, and being out of tram.

Also, it's hard to tell, but are you taking full cutter-width cuts with little or no overlap? If so, you may be leaving ridges between the cuts, especially if your end mill isn't absolutely 100% on its width on all cutting edges, and dead flat. I don't know what common practice is, but I tend to advance the cutter by .100" (2.5mm) less than its width, so a 1/2" end mill will be advanced by 0.400" to make the next cut.

When you get it all right, even though you can see the lines (like ploughing), it'll still be smooth to the touch with no ridges.
Title: Re: First swarf - at last!
Post by: CrewCab on December 08, 2009, 03:02:31 PM
Congrats Ian, glad to see you have a swarf pile of your very own  :thumbup:

I'd agree the lines are to be expected with a small cutter though it's probably a negligible amount,  flatting off with smooth emery and WD40 will probably give you a a glass like finish  :dremel: ......... but .........  how about a tiny pass with a flycutter :beer:

CC
Title: Re: First swarf - at last!
Post by: boatmadman on December 08, 2009, 03:18:35 PM
Fly cutter winging its way to me as we speak!  :D
Title: Re: First swarf - at last!
Post by: raynerd on December 09, 2009, 03:43:20 PM
I use to get those marks when my mill was not trammed in properly - however mine were slightly pronounced, are yours? As everyone else has said, a light cut with a flycutter should correct it if the mill is in tram.
Title: Re: First swarf - at last!
Post by: boatmadman on December 15, 2009, 07:43:20 AM
Got me a fly cutter, sharpened as per the  bogs method and the pics show the a before starting and finished item together.

 :D

Ian
Title: Re: First swarf - at last!
Post by: Darren on December 15, 2009, 07:51:22 AM
That looks a lot better  :clap: