(Dumb) Power feed question

I believe the readout on TouchDRO gives real time feed rate. ive only noticed it in passing but being a confirmed Luddite seat of the pants is all I can comprehend.
 
Sound, feel, and sight. I'm assuming your powerfeed, like mine, lacks actual ipm graduations. I just go by 'feel'. - That is, the sound, feel and sight of the cut. Are you getting the finish you desire? It may be surprising, but often the answer is 'speed up'. If your machine is bogging down, slow down. It's not a dumb question, but it's not CNC, so feel your way through - you can probably dial in speed and you'll know, if you watch and listen, what is too much.
Sorry for not having a concrete answer, but so much relies on your machine. Learning to sense it might be one of the keys to becoming a good home shop machinist.

GsT
 
I agree with @Nutfarmer & @benmychree. I always roughly calculate rpm to ensure I don't burn up a cutter. I have never calculated IPM. That's mostly for CNC programmers. Aside from the old Bridgeport power feeds, I've never seen a power feed calibrated in IPM. Without sufficient horsepower and rigidity, those numbers are not achievable anyway. Start low and increase until the vibration or surface finish tell you to stop.
 
The numbers on the dial are useless. The speeds on any vario head are indicated as "approximate" at eye level with the operator. Look, both the feed and the speed are gross estimates and are best handled coarsely.

So, how many decimals did that calculator give again? Hundredths of an inch per minute? Yeah, I'm laughing at you, those calcs are so far down in the weeds that neglecting belt slip to three decimals will ruin the output. Infinite monkeys, typewriters, and GI/GO all yank the rug out from under such bold proclamations of precision it's hard not to belly laugh here.
 
@Video_man : your response shows you understood the question and it was also useful. My dial doesn't have numbers but I could fix that. If I "calibrate" it like you did I would get useful numbers for ballpark feed rates. (I could even make the numbers match the feed rates!). Thanks!

I do realize that those feeds are for ideal situations but if it says 10 ipm and I'm running at 1 then I know I can push a little harder. Any kind of baseline is useful as long as one understands its limitations.

Sent from my Pixel 6 Pro using Tapatalk
 
walterwoj said:
@Video_man : your response shows you understood the question and it was also useful. My dial doesn't have numbers but I could fix that. If I "calibrate" it like you did I would get useful numbers for ballpark feed rates. (I could even make the numbers match the feed rates!). Thanks!

I do realize that those feeds are for ideal situations but if it says 10 ipm and I'm running at 1 then I know I can push a little harder. Any kind of baseline is useful as long as one understands its limitations.

Sent from my Pixel 6 Pro using Tapatalk
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I'd also consider the load that power feed can handle. I guess if you are approaching the feed from the low side you would notice if it bogs down or if a clutch slips etc.

I haven't added power feed to my mill mostly because the bolt-ons seem to be a kind of hack-y solution and I'm not familiar with how they work. A good one would have some sort of fail safe on overload.
 
After running mills for 50+ years it comes down to feel, sound and watching the chips. I often find that I'll manually crank the table faster than I set the feed.

Richard
 
Many DROs will display the feed rate - any chance yours does that? It's not always obvious.
 
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