This is a question I also will be lurking on. My little mill drill is typical of many small hobby machine types, and it has half the power of yours. That need not always be so, but I recognize there is a limit on how much to expect from these, both in respect of stiffness and cutting power. Mine may be all I ever need, but I hesitate to shell out good money on a drool face cutter to discover it is just too big.
Not that I want to be forever spending ages going back and forth over a surface with a 12mm end mill cutter, and maybe finish with a fly cutter, but it would be nice to have some perspective about what is the realistic maximum. I will likely play a bit with hiking the power somewhat until I risk breaking something, but my heart still thinks a refurbished Bridgeport (or similar) is where the HM smitten end up!
Thanks for the tip Aaron. My mill is 750W - so basically 1HP.For a small mill, Sherline makes an insert fly cutter that is basically a 1" single flute face mill. Mikey has recommended this cutter for small mills before and Sherline now offers it with a straight shank instead of the standard MT1 so it can be held in a collet.
I have one I use on my Clausing 8520 6x24" 3/4hp mill and it works great.
https://www.sherline.com/product/7620s-single-flute-insert-fly-cutter-with-straight-shaft/
The RF was 2 Taiwanese HP and the Lagun is 3 French HP (Spanish mill, French motor). I know those are bigger motors than what you've got, but at depths of cut like .040, it should be no problem. Just slow your feed if needed.Thanks for the tip Aaron. My mill is 750W - so basically 1HP.
Thanks also to @pontiac428. John - what sort of motor power did you have available when driving those cutters?
Thanks for the studied reply. A few follow up questions. HAAS does not sell an R8 arbor and the arbor I have accepts bodies with 1" bores, not 3/4", so that is one additional expense. I tried to find the SFM, all I found was some settings I don't understand, granted my head was wobbly at that point but should it be that hard to find SFM? Looks like their bodies are designed for CNC where everything is set in parameters, I'm happily manual, no CNC.I would not recommend the FM45 series positive rake face mill for stock removal and it is designed more for surfacing in softer materials or surfacing in steels. I would recommend a square 90 degree shoulder with minimal pocket rake insert/face mill (FM90 series) for stock removable in steel, but you will be limited more by Hp and rigidity. A 2.5" diameter face mill would be a good size for ferrous material, non-ferrous probably 3" in a FM45 style. I have a 2" face mill APMT/APKT style insert which is a 90 degree insert that allows more vertical cut. You can take a deeper cut and more cutters allows nice material removal. I lent mine out to a friend who needed to make some fingers for his bender using CRS stock and if I recall he was doing a 0.1DOC by 0.3" at 700 RPM, 8" IPM on his Lagun and removed a lot of material with a nice finish, he had to do something like 30 fingers.
Like David Best I also purchase the Haas face mill at his recommendation and went with the HS6NP in a 2.5", it uses their trigon type insert with 6 cutting edges and a DOC up to 0.3". I milled some 1018 CRS with it and the finish was like a mirror, I feel both finish and rate of material removal was better than my APMT/APKT style. The Haas inserts are pretty massive in comparison traditional inserts. If you are doing just steel and want deeper shouldering then the HRNP may be a better choice, there are 4 cutting edges, as these inserts can be both rotated and flipped. So an expensive up front investment but should last a very long time. They have a series of videos for each face mill that you can review. There are alternative brands, my older face mills are Iscar and Sandvik, they work great but often have proprietary inserts like the Octagons which can be quite expensive.
HRNP – Haas Rectangle Negative PositiveSHELL MILL BODIES - HAAS TOOLING
Explore high-quality Shell Mill Bodies for precision machining. Our range includes durable and efficient milling solutions for various applications. Find the perfect Shell Mill Body for your machining needs.www.haascnc.com
HS6NP – Haas Sq Shoulder 6 Negative Positive
Iscar 2" face mill 90 degree APMT/APKT steel shouldering, Iscar 2" face mill Octagon insert steel surfacing maximum DOC ~0.050", Sandvik 2.5" face mill 45 degree insert style with positive rake for aluminum surfacing maximum DOC ~0.1". RPM in steel is usually in the 600-1200 RPM, aluminum 2600-3500 RPM. Too high a speed in steel and not enough chip removal will burn up the inserts quickly, so need to look at chip load. Inserts for aluminum have sharper cutting edges and sit in a positive rake pocket. Fly cutters may work well to get a wide consistent surface finish but you are limited as to speed and DOC. In softer materials I use a 4" surface mill with 7 sharp octagons, positive rake and get a mirror finish in different materials running at around 2600 RPM and around 10 IPM. But a bit too big for your size mill.
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Thanks for the studied reply. A few follow up questions. HAAS does not sell an R8 arbor and the arbor I have accepts bodies with 1" bores, not 3/4", so that is one additional expense. I tried to find the SFM, all I found was some settings I don't understand, granted my head was wobbly at that point but should it be that hard to find SFM? Looks like their bodies are designed for CNC where everything is set in parameters, I'm happily manual, no CNC.
I see alot of posts about how much tonnage (tongue in cheek) can be removed in a minute while I'd be happy to remove 0.100 inch (normally 0.050") in a single pass with nice finish. Oh, about that IPM? huh? that's cranks per minute for me-yes, this is a crank post
The ability to mill to a square shoulder. I have APKT-style face mills in addition to the Haas - the Haas inserts are much more robust because they are considerably thicker as Mark said.Alright, sarcasm aside, I've read plenty posts stating 45 deg face mills are easier on the mill, what does a 90 deg shoulder mill gain me on a 2 HP mill (with power feed!)?