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It has been my experience that you never climb cut with a saw, always conventional.
And I think you would get less burr on the inside if you cut from the inside out.
Scott
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I have a few question on how to get the cleanest cut with a slitting saw on the inside of my hole. The pic included isn't the part, just a quick test, but will show you the burrs left on the inside and out.
A rail is going to be clamped in this hole and has a pretty tight tolerance. The smoothest cut possible is what I need (at least on the inside). There will be 7 of these parts in my vise to be cut in one pass after drill/tap. 6061-T6 AL, the saw I'm using is
Carbide Slitting Saw
2.0" dia
.062" thick
22.9 IPM
580 rpms
@ 0.45" woc (stock to be removed)
The cut went great with very little problems on my test but my material to be remove was 0.18" woc. Do you think these same settings at 0.320" woc it would go as smooth or split it up in two passes ?
Last was which is the biggest problem I have at the moment is which way to feed the saw in my part/clamp leaving my reamed hole without any deburring needed ?
The cut in the pictures was CCW climb cut from the left going right. I'm thinking if I switched the feed & spindle direction to cut from the right going left in CW, it might help the burring. Starting cut on the inside of the hole first, then exiting thru to the outside of my part. Any ideas ?
Or would the little green triangles in my tumbler get the job done ?
.
It has been my experience that you never climb cut with a saw, always conventional.
And I think you would get less burr on the inside if you cut from the inside out.
Scott
www.sdmfabricating.com
This should be a clear cut answer,.....wherever the cutter exit, the burr will be greater.
In aluminum I would use a HSS cutter, HSS can have a sharper cutting edge, a freshly ground triple chip or just plain slitter configuration,
on a 2" you're looking at about 36 teeth....perhaps less if chips are piling up between teeth.
Thanks guys going to give it another shot...
Konrad, have a link to a recommended HSS slit saw ?
Very close, 40 teeth. This one cost me about $100 and so far it's been a great little saw, but for some reason I too have noticed HSS cuts better in AL for some reason. Maybe it's me or how I'm setting things up, but really impressed with some of the cheap bits I bought vs the expensive cutters.
Sorry no link, the 40 teeth might work, just slow down feed for lesser amount of chip load per tooth.
Good coolant flow is very important too.
Carbide is more brittle and the very outer sharp edge it can't hold up as HSS would...
just the nature of the beast [carbide]. You can break a tooth allot easier too with carbide.
I grind my own slitters...since we are in the sharpening too, sometimes I re-tooth
a cutter to specs, we also buy larger blades for cold saws without teeth and grind to whatever.
Konrad
I think you made a great job with what you have.
I also think it will be very difficult to do better.
No burr with this kind of machining is almost impossible.
I would live with that and just remove burr if you only have 7 parts to do.
Jeff
I have had good results using a 3.5” diameter 30 tooth slitting saw on 6061-T6.
http://i72.photobucket.com/albums/i1...TSblankSaw.jpg
Here is my Tormach in action slitting using that slitting saw. BTW Which One’s Pink performed a great rendition Saturday night at the Key Club on Sunset of " One of These Days”
TTS SlittingSawon Tormach video by miltons_stuff - Photobucket
Here is the part after slitting. Any small burrs are removed by running in a Burr King vibratory deburring machine.
http://i72.photobucket.com/albums/i1...iant-Mount.gif
Don
Wow 3.5", man I thought I was pushing it. Going to run another part today.
I own a cheapy Harbor Freight Tumbler, wasn't sure if that would do the trick (haven't used it much). Curious are you running dry or wet ?
I bought a 125 gph sub-pump, but think it's a little much for this. Was going to recycle the water thru a 5 gallon bucket, but thought I need to filter this nasty grey mud foam/water some how, any suggestions ?
I don't think I was pushing it at all with the 3.5" 30T slitting saw. That worked very well for me as shown in the video. BTW I made the slitting saw arbor from a TTS machinable blank.Originally Posted by twocik
I deburr wet using 2oz per gallon of water of Metal Finishing Compound MSI-60 (available from Manufactures Service Inc. South El monte, CA 626-443-3057) with plastic encapsulated medium grade conical medium. I get a matt finish on aluminum.
I tried the filtering approach with my deburring machine but gave up. Now I just flush the used fluid and refill with fresh solution. BTW I used a magnetically coupled pump but the filters were quickly clogged.
KBC Tools & Machinery, Inc.
The 3.5” 30T HSS slitting saw was ~$22 from KBC tools.
Don
Remember, a smaller diameter slitter...if you can get away with, will cut nicer, less
fibration, cleaner cut... always aim for the smallest possible cutter.
I didn't find that to be true for me. It seemed that for me as long as surface speed was held the same by adjusting the spindle speed I got good results from small or large slitting saws. What did make a difference for me was number of teeth. For aluminum I prefer less teeth or coarse pitch. In cutting aluminum with my band saw I found that 4-6 TPI bimetal blade works really great. The 30T 3.5” diameter slitting saw worked extremely well on 6061-T6 as was shown in the video. Also I wonder if the smoothness of variable pitch band saw blade could duplicated with the slitting saw by dithering the spindle speed thus avoiding resonance issues and improving surface finish.
Don
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