Pneumatic De-Rimming ? Can we get details?

[DukeInFlorida]

I've de-rimmed a couple thousand .22 LR pcs in the past few weeks. I have BT Snipers outstanding de-rimming die and bottom punch. Both were very precisely made.

My arm is getting tired pulling the lever on my RCBS Rock Chucker press with this de-rimming process.

I know that Brian automated his press with some sort of a pneumatic ram, and that others have also done it. Brian did a clever video with a hidden foot pedal, and was able to process the de-rimming very quickly.

I'd love to get some "kit" parts and try to assemble a similar setup. I need to know what parts I need, and how to install them.

I'm hoping that this thread will serve to document the parts and construction for making the pneumatic modification work.

[Fla9-40]

I'd love to get in on this if it materialize!

[DukeInFlorida]

This is the thread I remembered:
http://castboolits.gunloads.com/showthread.php?t=122094

Brian's video would leave you to believe that it's on an automatic timer, but later on in the video, the timing mysteriously changes. FOOT SWITCH!

Lafaun suggested that a cheap 1.5" cylinder wouldn't do it. I'm guessing that both he and Brian got surplus large cylinders.

I need to have a size range.... 4", 4.5 inch, 5"?? for the cylinder. And, I also need some ideas for mounting, attaching the cylinder to the press. If it's not attached directly to the press, it's likely to lift the entire bench into the air.

I love cutting the learning curve.

Could I please get some discussion of the size of the cylinder that's needed, and how it's mounted? I have a sense for what's needed for the rest of the system.

[sprinkintime]

Duke; if you would PM me with you e-mail address I will e-mail you pictures of a set-up I made a while back on pnuematic de-rimming 22lr. My cylinder on this set was to small, you do need a 4-5inch bore to give you at least 2500lbs of pressure at 125 psi. without some type of safety device on this, its is very dangerous.

[DukeInFlorida]

PM inbound, thanks.

[Fla9-40]

PM inbound, thanks.

Don't forget to share! :)

[DukeInFlorida]

sprinkintime, is it OK for me to share your image with others?

[sprinkintime]

sprinkintime, is it OK for me to share your image with others?

Its up to you Duke, I have no problem with it, just to remind everybody that this can be very dangerous, like loosing the tip of your finger without some type of safety devise.

[DukeInFlorida]

Here's the image of sprinkitime's setup:
http://www.sebagosales.com/swagedbullets/pneu_setup_derim.jpg

[DukeInFlorida]

My best buddy came up to Maine today with a pneumatic cylinder, the solonoid, and all the parts to connect up a pneumatic system for the de-rimming.

Unfortunately, he brought a 2" cylinder, and that wasn't enough oomph. Even after we bumped up the pressure in my compressor to 135 psi.

Cylinders come in different diameters, and the next meaningful size is 3 1/4" diameter. I gotta get one of those.

I have everything mounted horizontally to a piece of 7" I-beam. Did some creative arc welding. The I-beam is kid of long, so will have to cut that down. When I am done, I should have a short machine, easy to place on the bench top, and run horizontally.

I'll post a picture a bit later on.

[rasto]

Thank you, looking forward.

[kend]

How much stroke do you need?

[DukeInFlorida]

My 3.25 " pneumatic cylinder has arrived, and I have run the cylinder to prove it has some very good power. However, the mounting of this new cylinder is different that the previous one, and I need to modify my weldment to accommodate the cylinder.

Also, I have decided to order a custom machined adapter to connect my cylinder ram to the press ram. Only then will I be able to actually run the de-rimmer.

Here's a video of the new cylinder:
http://youtu.be/gVqUCwJ4-2I

The required stroke is about 3.5". This new cylinder has a 4" stroke, and I think that will work also.

[DukeInFlorida]

OK, I have my machine up and running.

I'll do a full write up in a separate thread, regarding construction, concept, and where I got parts. I'll also share tips and ideas. The intention is to make your own de-rimming machine as easy to make as mine was, and save you some $$$. I'm not quite ready to start taking orders for processed brass, but might do that at some point in the near future.

In the meantime, here's a quick video shot with my hand held cell phone cam, showing the machine's operation.

http://youtu.be/FZxgDKrIM5Q

[scarry scarney]

Nice little video. Where did you find that air cylinder for $65?

[DukeInFlorida]

FleaBay . . . I actually see them there all the time. . .

[BT Sniper]

Looks good Duke.

Power sure is nice isn't it.

I noticed the poped tops of the few derimed cases in your box. The only time I ever poped the tops like that the punch was not in perfect allignment with the die. Dont' know if that is the case but something to consider. Maybe one of those Lee rubber gaskets under the lock ring of the die? to allow for self allignment. Don't know about that one though?? Use plenty of lube too. I've found you can't use to much when deriming.

I used a rubber end cap with a hole in it under the lock ring of the die for the 90 degree angle PVC pipe to conect to and hold it all in place. Works like a charm!

BT

[DukeInFlorida]

I'm noticing that when running the machine horizontally, the brass tends to tip a bit on the punch (because it fits somewhat loosely on the punch), and it's impossible to get a perfect alignment. I like your floaty idea with the Lee locknut. I have a solid lock nut on there now. Nothing gives. Maybe a little flex would help. And, I'm also thinking of cutting the I-beam way down and mounting the machine vertically.

I've already figured out the pvc pipe thing, using a curved 90 degree elbow.

When I was derimming manually, I found that as long as the brass was clean, I didn't need to lube once the punch and tool heated up. That doesn't seem to be the case with this version. Must be the brass tipping issue.

[rasto]

Pneumatic is lacking of the power as you realized.
Do not you thing that hydraulic force could be better solution?

[DukeInFlorida]

No, hydraulic is not a better answer. Pneumatic is fine.