Automating bullet sizer?

[Tazza]

Should be easy, motor rpm divided by 50 will give max speed.

The plate on the motor should tell you the rated speed

[Cue]

Some disappointing news, I tried sizing some .45 230g powdercoated bullets today for the first time and the machine doesnt have the power to push them thru. They were roughly .455/.456 so I used a .454 die and on the down stroke I had to hit the ram with a rubber hammer each time to get it to go all the way thru. I then tried to size the .454 bullets to .452 and the same thing. I lubed the bullets with the Aqua lube from Hitek as well. Not sure how to fix it other than getting a new motor and rebuilding the press? Maybe I can get more torque if my arm was longer or in a different position? Here is a picture of where the arm is at when it gets stuck. Any ideas?

[Tazza]

I had the same issue with mine on some over sized 158 gr swc, i had to hit the ram rod to push them through.

You may be able to get a little better performance if you are able to shorten the "cam" linkage, the shorter the travel, the more torque you will have. At the position it's locking up, you have almost all the force it can apply.

The only thing you can try is to loosen the die a little to get it pushing a little further around on the stroke, the next issue is, you need it to travel far enough to push the complete projectile out, or else one needs to push the next one out

[Cue]

So you mean move the bolt that goes into the arm closer to the center of the shaft?

[Tazza]

I mean shorten the flat plate that bolts to the motor, the shorter this is, the more torque it will have, but give you less ram stroke though.

[Tazza]

Shortening the other rod i don't think will change anything, or at least it didn't on my setup.

[Cue]

Yea, thats the same thing I meant. I dont think it will have enough stroke. I guess im going to have to look for a different motor and rebuild.

Anyone have a guess on how many foot pounds it takes to size a bullet from say .455 to .452?

[Tazza]

The one thing you can try, may not work, but yiu can set the feeequency in the vfd, you may be able to over run it a bit to get. more power. Set to say 65 or 70 hertz. It may mess with the motor design and heat up faster....

Increase your current limit too.

Again, unsure if it will kill the motor or not though

[Cue]

Tried that, didnt help.

[Cue]

Looking at the plate on my motor, I didnt notice it is only .12 HP or .09KW so its not even 1/4 HP. I may try the motor igolfat8 posted above that he bought, It isa 1/4 HP at 1725 RPM. Not sure how it mounts though.

igolfat8 have you built yours with that motor yet?

[Tazza]

Shame the higher frequency didn't do the trick

I'd like to think it will have an ISO mounting that you can throw another motor at fairly easily. Hopefully a more powerful motor will be easy enough and cheap enough to find.

[Ausglock]

That gearbox should take a 0.18kW motor

[jsizemore]

Don't know if you've tried sizing within an hour or 2 of baking before they get a chance to get near final hardness.

[Cue]

Tried sizing about 20 minutes after baking.

[igolfat8]

Looking at the plate on my motor, I didnt notice it is only .12 HP or .09KW so its not even 1/4 HP. I may try the motor igolfat8 posted above that he bought, It isa 1/4 HP at 1725 RPM. Not sure how it mounts though.

igolfat8 have you built yours with that motor yet?

No, sorry but I haven’t used it yet. I’m still waiting on my sizer to ship from Gremlin.

[KAYDADOG]

VFD's are great and have come down in price over the years. I believe with any motor rating as you increase the RPM the torque curve goes down. This is where the motor being used has to be sized accordingly. Larger is never the problem you can control the maximum torque or current with the drive parameters. You can't get more torque out of a rated motor by just increasing the rpm. Worked with VFD's in industry for many years. I could be wrong and just wanted to supply some information to anyone trying to make automated equipment.
Thank You

[Tazza]

VFD's are great and have come down in price over the years. I believe with any motor rating as you increase the RPM the torque curve goes down. This is where the motor being used has to be sized accordingly. Larger is never the problem you can control the maximum torque or current with the drive parameters. You can't get more torque out of a rated motor by just increasing the rpm. Worked with VFD's in industry for many years. I could be wrong and just wanted to supply some information to anyone trying to make automated equipment.
Thank You

I figured the torque would stay the same with the higher RPM, i hoped that the extra inertia would be enough to get that little extra bit to get it through the sizer die, but seems it wasn't the case.

[Cue]

What do you think would have more torque/power to push thru. A 1/4HP 1725 RPM motor geared 30:1 or a 1/2HP 1410 RPM motor geared 20:1?

[Tazza]

I'd like to say the 1/2hp 20:1 would have more torque, the thing is, i have found even at lower speed, you still have loads of torque with a VFD. You won't be running it flat out at 20:1, i think it will be too fast

[Cue]

I was thinking the 1/4hp since the rpm was higher and the gear ratio higher LOL, thats why I asked in the forum.

The 1/4hp would be running at 57RPM and the 1/2hp would be 70rpm so neither one would be too fast, would be just right speed