FREE Speed-Feed Calculators !!!

I received one of the Speed/Feed calculators today. I think it is priced fairly. It is well made, it is plastic covered so it should remain usable in the shop environment. It appears to offer all of the data that a machinist would use including data for lots of materials and hardnesses. A calculator like this is so much easier to use than punching the numbers out on a calculator. It's certainly quicker to use this without fooling around with the equations, and it ought to be more accurate than entering the wrong numbers or using the wrong equations in the electronic calculator.

In my basement shop, I use a chart on the wall that was copied from ??? years ago to set RPM. I've calculated chip load occasionally but it's generally too much trouble so I just don't do it and 'wing it' based on my (limited) experience/judgement. I think that I will use the slider for the feed and speed settings. As Bruno and Dave mentioned, there is a lot more information available with this calculator than I will ever use.

I'm a retired engineer who decided to build a hobby machine shop after retirement and who has very little practical experience in machining beyond what I've learned during the past few years. It appears that the slide calculator will be useful to me.

Roger

"B&D Surplus" wrote in messagenews: snipped-for-privacy@4ax.com...

Reply to
Roger Jones
Loading thread data ...

This is a periodic recurring spam offer from someone that never posts anything else other than spam for his calculator.

Posts to this newsgroup were on 12/20/06, 1/2/2007, 1/24/2007,

3/4/2007, 3/5/2007.

Wes

Reply to
clutch

Also in violation of Ebay's policy.

Reply to
K. A. Cannon

Sigh..Im a sucker for an honest reviewer

Ill order one off ebay.

Gunner

"Liberalism is a philosophy of consolation for Western civilization as it commits suicide"

- James Burnham

Reply to
Gunner

According to Gunner :

I think that you'll like it. Especially since you include horizontal mills in your collection. I've had two for several years, one near the horizontal mill, and one near the lathe (which I call single-tooth endmills. :-)

Enjoy, DoN.

Reply to
DoN. Nichols

Come out and we can shoot at 10 miles.

Lots of open space here in the desert.

Lots of miles and miles..of nothing but miles and miles...

Gunner

"Liberalism is a philosophy of consolation for Western civilization as it commits suicide"

- James Burnham

Reply to
Gunner

...Ive got a couple from Kennemetal, of a similar nature..found em right handy, but they are primarily formulated for use with carbide and I use a fair amount of HSS.

Gunner

"Liberalism is a philosophy of consolation for Western civilization as it commits suicide"

- James Burnham

Reply to
Gunner

DoN Nichols wrote: (snip)

Maybe because it's Friday after a long hard week, but I'm a bit foggy on exactly how you use the calculator to determine lathe speeds?

I get using the 1-tooth cutter approach (clever!) but...

If I'm cutting Soft Carbon Steel with HSS I get 80-120 ft/min...

How do I transfer that data to the flip side for an easy read of rpm per diameter?

I'm assuming I would put the tool diameter (eg 2.0") over 80 fpm and use a speed of 500 rpm... Is this correct?

Sidebar: I also sent for one of B&D's calculators... Nicely made, and if I can learn how to use it for milling and lathe work, it should prove darn handy! I'm just a hobby machinist for Live Steam purposes, and have a rough time remembering the handy info pro's can recall at a moment's notice.

Chet in Cleveland

Reply to
Chet & Audrey Roberts

I just got my free calculator from BD surplus - I agree with the other posters, you may or may not need it, and you may or may not like the price, but it is a nicely build slide-rule type calculator for SFM to RPM, recommended SFM as a function of cutter, chip load, and volume in cubic inches. The calculators have a McDonnell Douglas logo on them, which tells you they were in use in Aerospace machineshops. I don't think all the whining and name calling over these was warranted, and I thank BD surplus for sending me one - I will use it. I would encourage BD surplus though to include an FS prefix the next time they post these for sale to defuse those who feel obliged to stand up and complain. I bought some welding calculator from miller a while back, slightly lower construction quality, about the same price.

bill n

Reply to
William Noble

Yes.

You use the "SPEED" scale and set the *workpiece* diameter (instead of the tool diameter) so assume a 6" diameter workpiece, that calls for about 52-76 RPM. With a more reasonable 1" diameter workpiece, you wind up with a range of about 305-460 RPM.

And -- as you reduce the diameter, you can re-calculate for the speed as you progress. (Or -- if you are boring, use the ID as the "tool diameter", and work on the low side, since your SFM will be increasing as you increase the diameter. Recalculate fairly often here, to keep from taking forever on the first passes because you calculated for the maximum ID to be safe. I would suggest painting the face of the workpiece with layout die and scribing circles in it every 1/4" or so to remind you when to recalculate the speed. (Of course, if your lathe has only belt speed changes, calculate when you need to change the belt to keep the SFM within reason.

It certainly saves me having to look up SFM for a given material. (I do wish that it included 12L14 (my favorite steel) in its charts. I should look that up and past it on a clear space on the calculator.

You can also use the feed/tooth to get a good starting point for the lathe's feed, if yours has power feed.

The "CUBIC INCHES" scale is more reasonably used if you know the maximum CI/Min figures for your lathe's horsepower. And if you're worrying about that, you are into serious production calculations. Mostly, you can use this calculator to give you good starting points (to not exceed), and you can make your own tradeoffs of time against tool life. Most of us would prefer to improve the tool life (expensive) at the expense of time (free for a hobby metalworker). But -- if you are in a position of renting time on a machine with the tooling included in the rental cost rather than supplied by you, you might want to go to the high end of the range given by the calculator, since it is the time which is costing you, and the tools can be considered to be free.

Of course, after a while, you will (for most things) develop a feel for what works for your common workpiece sizes, but if you go to something particularly large, it will help again by giving you a sanity check on your settings.

Enjoy, DoN.

Reply to
DoN. Nichols

That's an odd favorite steel. Machining Leadloy is like machining magnetic aluminum. Where is the challenge in that?

Never thought about it until now, but I suppose if I have favorite steels to machine they are DH2F and Viscount 44. Both are pre-hardened to Rockwell C 44/46 H13 type steels. I like cutting hardened (RC 48/52) H13 too, but the two day wait to get it back it from the heat treater is painful. :-/

Reply to
Black Dragon

DoN. Nichols wrote: (snip)

Don, thanks for the very detail explanation!

I didn't realize how poorly I understood how to use the darn thing. I had to stare at that Speed scale for several minutes before it all clicked on which scale referred to what! Once I understood, it was completely obvious.

Now I REALLY like that scale! It may the first 'tool' I actually wear out!

Chet in Cleveland

Reply to
Chet & Audrey Roberts

Im still looking for mine in the bottom of the box with the ball screw.

John.

Reply to
John

is this black dragon the same one that had a great site explaining how to set up email spam filters? If so, hello

Reply to
William Noble

No sir Mr Noble, I'm not the same Black Dragon.

OK, be that way, but right back at ya' anyway. ;-)

[...]
Reply to
Black Dragon

Reply to
William Noble

Black Viper has returned.

formatting link

Reply to
Michael Rainey

Whoopee!!! - that's the guy.

note to others - this guy had insightful information and great ideas on things like spam filtering, worthy of a visit and of your support based on past performance. But this is OT

Reply to
William Noble

Done,

Tom

Reply to
brewertr

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