Any way to modify speed system on DP1550?

Hello;

I've done a lot of searching on drill presses, and the Ridgid 1550 is on my short list - - But:

The lowest speed offered on this product, 300rpm is just a little bit too high. Rather than loosing my purchase to another competitor's dp, can anyone offer a "fix" that will let me reach a lower set of speeds.

(1) I don't mind changing parts - even if it is not covered by a warranty. Been there, done that on my cars to get the performance I wanted.

(2) I know the induction electric motor is not the way - induction motors can only be controlled by $$ frequency controllers.

Any ideas??

[spowell]

Do you mind being more specific as to what you are wanting to accomplish with the DP? Based on this and your other post I am assuming it is cartridge case related. I own the DP1550 and also reload. I might be able to help with your decision if I knew more what you have in mind with case milling and forming.

[UO_Woody]

You would have to change the idler pulley set up so the belt from the motor would be on the same size pulley going to the spindle at the idler.

Other than that, you would need to increase the diameter of the spindle pully to slow it down.

I sure would want to have my stock clamped good as this would generate much more torque!

Originally posted by spowell:
Do you mind being more specific as to what you are wanting to accomplish with the DP? Based on this and your other post I am assuming it is cartridge case related. I own the DP1550 and also reload. I might be able to help with your decision if I knew more what you have in mind with case milling and forming.

Another reloader in the forum, most fortunate!

Ok spowell, I *try* to keep this brief.
I have evaluated my current case trimming method, and decided it takes too many different operations from several tools to trim & chamfer the cases.
My solution is to take the cost of a robust, dedicated trimmer {~$150}and apply it to a tool that could preform other functions in the shop when I was not reloading.

From my research, it seems that most electric trimming machines rotate the cutter at <200 rpm.
I have to believe that high speed is not good for trimming brass.

Now, in all but heavy $$ industrial dp's, we are *stuck* with induction motors that rotate at a set rpm level. The design of the single-phase motors dictate they cannot be controlled with simple voltage changes.

Only three methods to control rpm are technically feasible for the hobbiest.
Listed in order of greater expense/difficulty:
1 Mechanical with pulleys.
2 Replace the existing motor with a 3 phase unit and utilise a single phase input, three phase output variable speed drive to control motor speed.
3 Controlling by variation of the frequency of the voltage applied to the motor.

Each method has it's drawbacks.
1 Finding suitable pullys on the secondary market that will install on existing hardware and calculating the new speeds.
2 Finding a used 3 phase motor with the proper frame type and output shaft and building the electronic controller.
3 Venturing into a complicated electronic project requring a microprcessor controller.

Whew!

[spowell]

I wouldn't think that 300 rpm (minimum speed) would make a difference in trimming operations. RCBS makes a trimmer that utilizes a power drill as the power source and although I don't remember what it's rated speed was I remember a buddy of mine had one and would always exceed 300 rpm. He could consistently shoot 3/4" to 1 1/4" groups at 100 yds without much detail to load consistency, case grouping by weight, bullet sorting, etc. He would get as many reloads out of a set of brass as I would and I don't ever remember him having any problems in the neck area that weren't explained by other problems such as damage during bullet seating, etc.

For chamfering I also don't think that you would encounter problems. You could also probably do neck sizing if you took the time to set it up correctly. I had been looking at trying to modify this:

http://www.rockler.com/ecom7/product...rings_id=10592

into doing all three operations. If it wasn't so expensive I might give it a try.

You also may want to check out this link. They talk about using a drill press to prepare brass.

http://www.reloadbench.com/ubb/Forum17/HTML/000057.html

Hope it helps. I don't think you will be able to get benchrest accuracy from using the drill press, but heck, if you listen to the benchrest people you almost have to hand-form the entire case and apply 10 coats of wax to get mediocre performance.

Originally posted by grey44ghost:
Spowell, if "fnbrowning" really is hung up on 200 RPM to mill the cases, why doesn't he just change the 1725 RPM motor on the DP1500 or DP1550 drill press to an 1140 RPM motor and it would give him 198.26 RPM. Since he was looking for 200, there you have it. Use the same pulleys it originally comes with and just look for the 1140 RPM motor with the same basic mounting base and shaft size/length and rotation.

grey44ghost;
That sounds like an excellent idea. And I have considered it. By way of research, I had previously looked at the Grainger catalog for a replacement motor.

Capacitor Start Totally Enclosed Fan Cooled Motor, HP 1/2, RPM 1140, Voltage 115/230 V, NEMA Frame 56, Service Factor 1.00, Frequency 60 Hz, Mounting Rigid, DAYTON $290.75

OUCH! Now, that's for a new motor, not saying I couldn't find a used motor, but 1140 rpm
does not seem common. Will keep your suggestion in mind.

grey44ghost;
Like I said, I think the 1140rpm motor sounds like an excellent idea.

I agree that an ODP motor should do, it just that Ridgid uses a TEFC, and I figured the design engineers thought the fan ventilation was necessary.

Now you must be using a better search technique than I, because I've search also, and I just don't see a lot of used motors out there that fit the specs. I invite you to PM or email me some links.

Thanks for your help.