Radio Control/Foot Pedal Foundry Hoist Prototype

BTW, if someone lacks the common sense to know not to use my setup for hot metal, I really hope they will post a video so we can have a pool based on how long it lasts and which part cooks off first. My guess would be the nylon webbing would be the first to go, followed by the lipo battery (the battery would be fun to watch) about the same time the receiver for the servo should start falling in blobs of burning plastic and then the drill battery would light up the night and finally the drill case would start dripping. Now that would be an interesting video! Looking forward to it.

Denis

 

Good question, I'm not sure. Aviation is a highly regulated field, any piece of navigation or weather equipment goes through multiple layers of testing before it's accredited for use and put into service which I would think dilutes but does not eliminate liability. BTW, shortly after the incident, a nation-wide bulletin was issued highlighting the system's vulnerabilities under certain weather conditions and establishing set procedures to be followed when a problem is detected. At the time, that system, in one form or another, had been in service nation-wide for decades and was proven to be reliable except under certain fairly unusual circumstances, in the ten+ years I used the system, problems occurred only 2 or 3 times and self-resolved in a few hours. The system has since been replaced, the new system is very good however it's not completely free of vulnerabilities so it still requires the users to exercise good judgement.

 

And now back to our regularly scheduled programming....

 

Kelly,

What sort of battery did you chose? Maybe a 12v motorcycle battery? Lipo? And the motor is what wattage and uses a reduction gear? Stepper? Perhaps the details on the control unit might also be of interest. That looks like a very nicely thought out and executed lift system.

Denis

 

I buried a couple responses within this quote.

Thanks for the details, Kelly. Linear actuators, wireless devices, pulse width modulators and DC motors, servos, etc. have so many potential uses in the foundry to make life easier or even to make things possible that would be out of reach if attempted by hand.

Denis

 

Awesome thread! I am an RC Airplane enthusiast so I got a real joy seeing you combine the two!

 

Thank you, Billy. I have been using it now for 6 weeks or so and it has proven to be reliable and very convenient. It is so much handier and smoother than using a chain fall hoist. I never want to go back to a system that does not allow me to have both hands free.

Denis

 

Just a little follow up. The hoist has been used many many times by now and continues to behave itself. I really like the variable speed and the foot control. Having both hands free has proven very valuable and it’s smooth lift action quite handy. The last couple days I’ve been using it on a 450 pound flask/mold. I always use the drill motor switched to “ low gear.” It did not slow significantly or complain with that load. What it’s actual limit is I don’t know. FWIW.

Denis

 

I made a couple of small upgrades to the foot control which I wish I had made from the start

First, I added a "Push-on/Push-off" switch to the top of the wood cabinet of the foot control in a location that is convenient. This makes it no longer necessary to bend down and push the button in the control unit housing. This is a small change, but in a molding session I found myself turning the unit on and off many times in order to conserve battery life. Being able to just use my foot to turn it on or off is a really sweet upgrade.

The second change was to add a pilot light to the power circuit so that I could tell at a glance whether the power was on or off. The way the control unit was designed, the display screen goes dark a few seconds after you turn on the power. Then, to see if it is under power, it was necessary to roll the selector switch which would momentarily light the display screen if the power was on. But, I bought a very cheap LED setup for a 6 volt circuit and added it to the power circuit as well. The LED only draws 15 milliamps. Now that the LED is in the loop, it shines very brightly when powered. NO more guessing and I am much less likely to leave for home having forgotten to turn off the power to the control unit. The servo in the lift has its own (fairly dim) LED which I will likely upgrade soon just so it is easier to see.

You can see the red dot of the LED just below and to the right of the end of the control unit and the added button is the silver button below and on the midline of the control unit.


The LED is on here but did not photograph well. Better seen is its reflection in the end of the control unit case---the red spot.


In my eyes, this was a very simple and worthwhile improvement.

Denis

 

An update on the foot control. Since I installed it in March of 2020 the control has been in continuous use. It has served my need for hands-free hoist operation very nicely. I did have to replace the RC transmitter once as the original failed a couple months ago. The transmitter uses 12V DC power which I have supplied first with 8 AA batteries (short life span), then a lipo battery—-mich better life but somewhat a nuisance to remove, charge, and reinstall, and most recently using a small 12V the purpose sealed battery with flat tabs. The 12v battery is convenient as I made a couple of lugs on the box to which a charger can be attached without removing the battery from the control—-a convenience factor I really like.

The battery is securely mounted in a PETG box I printed for the purpose.

Here are the charging terminals located under the foot pedal out of the way. I printed terminal covers to prevent shorting across the 5/16" brass bolts that serve as terminals. To my surprise, the threads printed as part of the covers threaded right onto the bolts. The accuracy of the printer continues to amaze me.



Here is a view with one cover removed and also shown are some foot pads that were printed and screwed to the bottom of the control.


Denis

 

Here are a couple more pics of the underside of the foot control box showing the batterybox in place. I thought some about putting a door over the opening in the wood box, but decided to leave it open as whatever sand works its way into the box can also work its way out if there is no door.

Here you can see the underside of the two terminal with their 12 ga wires soldered into centered holes. The terminals are just to the left of center and in the center up and down of the photo.


The entire underside of the box with feet in place and battery box in place. Yes, the outer wood box leads a hard life on the foundry floor getting slid around through sand, things dropped on it, etc. It no longer looks bright and fresh. But it keeps on plugging along. (Hmmm, sounds something like ME!)


Kind of whimsical, but I like the 12-Volt Badge.


Denis

 

And another update to the foot pedal saga.
That little push on push off switch that I added recently has worked well for about a year. However, it operates in the filthiest possible environment and gets molding sand ground into it by my foot pushing the button on and off repeatedly.. Not surprisingly, it has failed. recently. I wanted to make some sort of protection for the switch or buy a suitable switch for use in harsh environments. I searched around for such a switch online, but really did not come up with anything that would actually fit the space and offer adequate protection. So I decided to make some parts using 3D printing and cab drawing. Here are some images of those parts.

First a CAD section view: 1/8" neoprene diaphragm is sandwiched in the gap shown. A 1/4-20 screw pinches the two smaller central piece together and #6 wood screws pull the ring down onto the thicker bushing and that bushing seals to the box with silicone.


The overview with the bushing in place


Next Diaphragm


Center button without screw


Pilot light on and fixing ring placed but not screws


I think this should be fairly bullet-proof. I will update sometime down the road.

Overall, the foot pedal has become an essential part of my molding operation. When/if it fails, it is a major inconvenience.

Denis

 

And I put it to use this morning. I looked down and this is what I saw---pretty normal environment for it I'm afraid.


Denis