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Turn Your FX-120i into a Prometheus

Thanks Kiba. I appreciate all the work you put into yours. It took a year of push to get me to finally take a serious look at it.

3D printing is an amazing way to build things like this. I used electronics parts I had already, printed everything else, and spent $0 to get to the point of the first video. I went through 3 or 4 different ideas for holding the motor and rotating the measure, and was able to evaluate them all in no time. It took a while to get all the dimensions just right, just change a number and hit print. Come back 30 minutes later, try it, change the number again, hit print.

I'll try the 2-pan method soon. I have a few tweaks in mind that should make it more convenient to use and I'll try to work out the fastest method.
 
Thanks Kiba. I appreciate all the work you put into yours. It took a year of push to get me to finally take a serious look at it.

3D printing is an amazing way to build things like this. I used electronics parts I had already, printed everything else, and spent $0 to get to the point of the first video. I went through 3 or 4 different ideas for holding the motor and rotating the measure, and was able to evaluate them all in no time. It took a while to get all the dimensions just right, just change a number and hit print. Come back 30 minutes later, try it, change the number again, hit print.

I'll try the 2-pan method soon. I have a few tweaks in mind that should make it more convenient to use and I'll try to work out the fastest method.

You are 100% right on the utility of a 3D printer for rapid prototyping and the amount of time it saves when trying different designs to see what works best... not to mention being able to fabricate part geometries that would be very difficult (or impossible) to fabricate via conventional means. I transposed 2 numbers when modelling the bracket and pulley offsets for the Harrell's on my setup and didn't realize until after I machined everything and went to assemble it. Ugh. Had to find more pieces of aluminum, more time on the milling machine to remake them, etc. Set me back a couple of days because of material and machine availability. With a 3D printer it would have been easy, fix the number transposition in the model dimensions and reprint it.

Regarding the 2 pan method with the plastic cups you're using, not sure how uniform the injection molding is in regards to weight but small pieces of scotch tape will probably bring the lighter cup up to weight to match the heavier cup very easily.

Adam, one issue I ran into with my setup that I'm not sure if you've tested with yours... have you tried sending large charges of large kernel powders like H4831 through the drinking straw drop tube? While I never had issues with "normal" charges of 20-40gr with powders like N133, Varget, H4350, H4895, RL16, etc, I did some load development for a friend's 7 SAUM and ran into drop tube bunching/clogging issues with large charges of H4831 (he couldn't get the shorter cut H4831SC.) I was occasionally having H4831 bunch up and clog in the drop tube right at the exit nozzle, and a standard drinking straw has a smaller ID than the copper reducer nozzle I used. I was able to eliminate the bunching by slowing down the motion of the servo and powder throw to release the powder into the drop tube over a longer time; the bunching only occurred when running the powder throw at full speed and a ~60gr powder charge was being released into the drop tube very rapidly. Just something you may want to investigate. Since your straw drop tube is a uniform ID from beginning to end and not slightly reduced at the end like my copper drop tube you may not have an issue with large charges of large kernel powders. I ended up tweaking the code and used a potentiometer as a "speed adjustment" that applies only to the dispensing stroke of the servo so I had the ability to slow things down during the dispensing stroke if needed to prevent bunching in the drop tube.
 
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Picking up on Kiba's comment about large kernel powders . . . the very worst I've ever used is N570. It's not only a large kernel, but it's also a thick stick. Neither the V1 or the V2 trickler can handle it without frequent jamming. So I'd fully expect the powder measure (shearing) and perhaps the drop tube (bridging) to have great difficulty with it (and perhaps with other powders).

So I wonder if the stepper motor on the Thrower has enough torque to deal with the shearing that may need to take place?

And if the AutoTrickler can be operated separately from the AutoThrower after this upgrade is done? Just in case.

ETA: I've ordered one anyway, figuring at worst you got it mostly right lol.
 
I will be testing with large powder soon. The straw is larger diameter than the nozzle that comes with the Lee, so it's at least better than the measure is out of the box. The straw diameter is about .25".

And you can use the trickler without it, just disconnect the cable and it should work the same as before.
 
Picking up on Kiba's comment about large kernel powders . . . the very worst I've ever used is N570. It's not only a large kernel, but it's also a thick stick. Neither the V1 or the V2 trickler can handle it without frequent jamming. So I'd fully expect the powder measure (shearing) and perhaps the drop tube (bridging) to have great difficulty with it (and perhaps with other powders).

So I wonder if the stepper motor on the Thrower has enough torque to deal with the shearing that may need to take place?

And if the AutoTrickler can be operated separately from the AutoThrower after this upgrade is done? Just in case.

ETA: I've ordered one anyway, figuring at worst you got it mostly right lol.

I also had occasional trickler tube stalling and belt slip issues with the H4831. I still need to relieve the trickler main body around the "pickup window" in the trickler tube to give the powder more room to move around, I think that will eliminate the occasional binding and belt slip with H4831.

Regarding the powder measure having to occasionally cut kernels... I think the Lee measure uses some sort of flexible plastic "wiper" to avoid cutting kernels.

On my Harrell's based setup I used a high torque servo so when the measure cuts a kernel it has plenty of torque to power through it. The Lee's wiper design probably avoids this entirely if it works as they claim it does, and Adam's video seems to prove it. A no-cut measure will also prevent the shock/vibration when a kernel is cut from disturbing the scale and stopping the trickler, another issue I had to figure out and work around with the Harrell's.
 
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I also had occasional trickler tube stalling and belt slip issues with the H4831. I still need to relieve the trickler main body under the "pickup" window in the trickler tube to give the powder more room to move around, I think that will eliminate the occasional binding with H4831.

+1 On belt slip issues with H4831SC.
 
Picking up on Kiba's comment about large kernel powders . . . the very worst I've ever used is N570. It's not only a large kernel, but it's also a thick stick. Neither the V1 or the V2 trickler can handle it without frequent jamming. So I'd fully expect the powder measure (shearing) and perhaps the drop tube (bridging) to have great difficulty with it (and perhaps with other powders).

So I wonder if the stepper motor on the Thrower has enough torque to deal with the shearing that may need to take place?

And if the AutoTrickler can be operated separately from the AutoThrower after this upgrade is done? Just in case.

ETA: I've ordered one anyway, figuring at worst you got it mostly right lol.

I just tested the throw with H1000, and it clumps in the funnel before the tube and will not flow. I'm surprised because it works perfectly with Varget and it doesn't seem that much bigger.

It will be an easy fix, to widen the opening and use a bigger diameter straw, but it's not something I will get to until after August. To anyone who asks I would send the upgrade part for only the cost of shipping after I get it ready. Likely a larger tube would not be desired with any other type of powder because it would flow too quickly... the straw diameter regulates the flow so it will not bounce out of the cup. So long term it might be an option or maybe there would be an adapter to insert the small diameter straw into the larger hole.
 
Just wanted to pipe up here for a short report on the Autotrickler (A/T) with my A&D FX-120 scale.

A few days ago, I went through a loading session to charge powder and seat bullets for 400 cases in preparation for the FCNC & FCWC in the Deranged Dominion next month. I would load 100 cases at a time then seat the bullets. I kept the powder load that I used to set the A/T to the target weight then started the process. At times, I walked away for an hour or so and even had dinner before doing the last 100. I had to re-zero the scale a few times, usually after walking away for an hour or more. At the end of the process, I weighed the target load used to set the A/T and it was dead nuts on.

I would take me about one hour to load 100 cases. Many times, I forgot to drop the initial charge, but I eventually got into a rhythm. Most of the charges were dead on with some dropping a kernel or two more than target. No big deal.

I would have liked a bigger receptacle on the A/T for the powder, but I'm thinking that with the Autothrow, you can get a lot closer to the target weight consistently compare to using measuring spoons to dip into a bowl full of powder. At least, I hope so.

At any rate, it was twice as fast or more compared to how I was doing it before with a Chargemaster and the Omega trickler on the A&D scale. It's also les handling of objects, which is always nice for older people and repetitive tasks; we like them simpler.

That Autotrickler is a fine device and I'm very pleased with mine. Looking forward to the AutoThrow device.

Also, at this point, with all those automated devices, seating bullets is now the longest single task. Anybody working on an automated bullet seater?
 
20 cases a minute is fast. I use the 21st Century lathe. I get good consistency, but I can't do 20 a minute. Interesting.

Years ago I bought one used from Brad Sauve... took a good look at it once I had it in hand, and put it back up for sale. Kinda like the Gracey trimmer, its one of those things that is way fiddly to get set up. Three independently adjustable cutter blades, IIRC. Once you get it set up, you don't *ever* want to touch the adjustments. If you're going to use it for one caliber, and one caliber only, fine. Otherwise... ugh.

We need a hopper fed auto neck turner. Load up 100 and go away. Dreaming, I know.

With the advent of the small open-source micro-controllers and new disciplines such as 'mechatronics'... I think it's entirely possible that some bright spark will work the kinks out sooner or later to scratch their own itch... and the rest of us will be more than happy to pay them for it.

I mean, that's how things got where they are with Adam and the AutoTrickler and AutoThrower... ;)
 

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