Anyone use slitting saw on 440 on aluminum?
What were your feeds & speeds. I wanted to hear from the experienced folks in the room. Im.looking into adding this capability to my tool belt. 440 doesnt have alot of power, my concern is the typical low rpm used with slitting saw.
Please share any words of wisdom, f&s, helpful hints.
I know on my 1100mx I have to use low belt to avoid stalling a ~3" saw when doing part-off kinds of things. I spend the rest of the time in high belt so I try to avoid using the saw much.
I certainly expect to be in low. Which i never use, but to part off or cut an external oring groove. A slitting saw seems necessary.
You didnt specify what kinds of f&s you were using.
IME F&S are highly variable with saws. Maybe because I don’t do much of it but everything has an effect - material, saw thickness, arbor, DOC, setup, runout, coolant, etc.
Much less of a thing if you’re only doing small cuts, but cutting off a 1"x2" part is different.
Often even in low belt I can’t run them as slow as recommended. Most of mine have a fair bit of runout which doesn’t help, so it turns into an overly conservative cut because I dislike breaking or jamming saws.
Aluminum likes to get hot and swell and jam thin saws without coolant, and if you push too hard thin saws can also warp so all I can advise is take the F&S recommendation for your saw and start much lower until you get an idea how it’s running.
what diameter saw do you need to use? You don’t need a lot of power with the right feed.
I dont have one. Im trying to get details before I do. Im concerned the 440 doesnt have enough power at the rpms necessary for slitting saw.
So im trying to find other 440 owners who have used them & get their take.
The right arbor makes all the difference. I tried for a couple months (.3mm slitting saw) with a couple homemade arbors that were pretty good (about .01mm concentric runout) and it was pure problems. Then bought a Karnasch (expensive) arbor with less runout than my mill and it worked the first try. And successive tries at higher feeds and speeds. I don’t know what you’re cutting but you might be able to use form mills. I also use a concentric spiral path to keep the load consistent.
Slitting saws are a nightmare because the manufacturers don’t seem to publish the feeds and speeds or they are just a range for all metals. The higher end slitting saws sometimes have better feeds and speeds but it’s like a big secret. I feel your pain.
You have a 440? Im looking to use the saw on aluminum for parting & features like oring grooves etc. My plan is to buy the tormach arbor & blades to start off.
What kind of feeds & speeds worked for you?
I have an 1100 but I’m making watch parts. I don’t think power will ever be your problem unless you’re singing thick slitting saws in hard metal. I’m assuming if you’re cutting o-rings you don’t need much depth. Have you considered t-slot mills or a form mill instead of slitting saw? Maybe even a lollipop or top/ bottom chamfer mill.
The problem with slitting saws is the spindle is pretty weak at slower speeds.
While there may be 3HP peak spindle power, it takes far far less to stall the spindle at the lowest speed available.
440 has 3/4 hp, so 600 rpm i expect to be pretty wimpy. 600rpm is minimum i believe on 440. Hence the request for 440 owners to share.
I have thought about tslot cutters but it seems like oring sizes fall in line with saws better & you can stack saw blades to get the width you need. It seems like tslot cutters dont have the depth needed for orings. With saws you have ample blade so oring depth isnt a problem.
I’ve got that chart but I dont know how that translates to real world.
I’ve never used or calculated a slitting saw on the 440. I have a cheap slitting saw but have not had the opportunity to use on the 440 as I changed the part design it was intended for to where it would not be needed.
Using the chart to program F&S and how I’ve found it translates…
The 1500MX has curves for running over 100% short duty. I find that I have to treat this curve to already being above what it can deliver at 100% for extended periods of time. On high belt, if I try to program to the limits of the chart (using FS/HSMWizard), it gets “sketchy” in that it may run for a while but I may have to watch it while running and may have to feed hold as I hear it stall and then have to back down the overall parameters down if I was to run production (which means that part could have bad finish). It will run but then stall over multiple passes or length of an adaptive pass that doesn’t “breathe” for less engagement/move without cutting given they are generally adaptive Fusion paths and would need to back down the rates.
I’d like to hear if a more experienced machinist has a different opinion or process of this curve on the 440. I consistently hear that Tormach want fast, light and NOT wide.
Not knowing how aggressive you have tried in the past, where I’ve had this chart front and center since I first started programming mine and was always trying to reach the maximums, I wouldn’t recommend using more than 80% of the advertised power/torque if you want repeatable and hands off. Maybe 75% at most.
If you haven’t been using the chart when programming, I would suggest taking the F&S of an operation you are confident of and are using in production. What is the calculated torque/HP for the F/S/DOC/WOC? Compare the calculated value to the chart relative to how close to the limit you are pushing it in percentage. I would then program the slitting saw with that % of comfort against the power/torque curve.
I would probably spend some time with FS/HSMWizard to see if there is a combo of F/S/DOC that will run on high belt. Probably not possible to stretch that one given your F&S is calling for close to minimum RPM, though…
Yeah SFM is usually the problem with saws, especially since most are HSS.
To get 100 SFM, a 3" HSS saw is only turning 127 RPM.
For a small machine with limited power at low RPM you need to shrink the saw diameter (clearances and arbors can become an issue) and/or move to carbide saws ($$$).
