Drill Press RPM for steel

[Iplayfarmer]

heres what my little old Delta has..and its about 10 years old. Model is still made..

My drill press has two sets of numbers, one for 60hz power supply and one for 50 hz. power supply. The numbers on yours correspond to my 50 hz. I wonder if your old Delta speeds are based on a 50 hz. power supply. It would be interesting to find out.

My only concern with a speed control, is its going to reduce the torque and power of the motor also. If a simple dial control would /could control a drill press they would be using these instead of a series of pulleys.....just to save $$$

when i slow down the speed of my grinder, its way easier to bind up the disk during grinding...less POWER. so if you did this to a drill press, it might not be able to actually drill thru the steel????

I think you're right about cutting the power of the motor when you reduce the speed. I think a router speed control would be good for reducing the speed from 600 to 400 or something like that, but won't work well for reducing the speed more than about half of the the nominal speed of the machine.

 

[grsthegreat]

My drill press has two sets of numbers, one for 60hz power supply and one for 50 hz. power supply. The numbers on yours correspond to my 50 hz. I wonder if your old Delta speeds are based on a 50 hz. power supply. It would be interesting to find out.


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\weird..mine has a 60hz plate on the motor. nothing else stating 50HZ.

 

[wawajake]

Now I know why when I drill steel , my bits don't last long.(and I just use some old 10w30 in the hole)

I use whatever speed the drill press was left at last time I played with the belts and pulleys. I always thought fast was better , but then I do more woodwork than steel !
I learned a lot from this thread, I am guilty as charged and will mend my ways for steel ....I will set pulleys to slowest speed and buy some cutting oil !!! And maybe I will save some time no longer spending time in hardware store buying more bits.

thanks folks

 

[grsthegreat]

Now I know why when I drill steel , my bits don't last long.(and I just use some old 10w30 in the hole)

I use whatever speed the drill press was left at last time I played with the belts and pulleys. I always thought fast was better , but then I do more woodwork than steel !
I learned a lot from this thread, I am guilty as charged and will mend my ways for steel ....I will set pulleys to slowest speed and buy some cutting oil !!! And maybe I will save some time no longer spending time in hardware store buying more bits.

thanks folks

then buy a "drill doctor" and sharpen the old bits. that machine is AMAZING.

 

[sparc]

This ought to do it... Router Speed Control

I'm sure there are options available from other suppliers besides Harbor Freight.

These are made to work with universal motors which are series wound; many of which can be operated from either AC or DC. These are the types of motors used in portable power tools.

I don't believe a router speed control will work on a motor with capacitor start, which is a type of split-phase induction motor and commonly found in stationary power tools like table saws, band saws, and drill presses.

 

[sparc]

I am guilty as charged and will mend my ways for steel

Bit speed is just as important when drilling in other materials such as wood.

I use Rapid-Tap when drilling steels and get good results. It does not leave an oily mess but its not cheap. A pint can will run you around $5 to $7.

 

[BobRip]

This ought to do it... Router Speed Control

I'm sure there are options available from other suppliers besides Harbor Freight.

This is not for use with induction motors. That is what most if not all drill presses use. So do NOT use this on your drill press. It may work, but you risk damage to it and the drill press.

 

[Wyobuckaroo]

My best two pieces of are...........

ALWAYS buy quality high speed steel drills.
Like Cleveland brand or other good name brand like you will find available on Granger, MSC, or other machine shop accessory web sites. Hardware store drill are not going to last well enough to even justify the lesser price.........

Use the formula............
For most mild steels......... 300 divided by the diameter of the drill.
This will give you a ball park starting RPM to run the drill at.

For larger drills. Drill a pilot hole for the drill. The pilot hole should be the diameter of the center part of the drill (web) This lets the drill cut the whole width of the cutting edge. This will help keep the hole true to size, neat and clean.

Use a cutting lube........ NOT old motor oil...........

Good luck