Powered all-thread and nut lift

[Thorsteenster]

Not sure what this is called, but the all-thread is stationary and has a nut on it, so when the all-thread is turned it moves the nut back and forth depending on which way it's truned.
I saw this somewhere, don't think it was RC but seems it could be fairly useful.
Anyone heard of this, or used it/seen it used, and if so, does it work fairly well?

[Roadmasters]

its called a screw drive or gear drive. talk to freddy, **** tell you all about them

[CatdrvR]

Yes Roadmasters is correct, it is properly called a screw drive and is used for all sorts of things in our niche hobby. For instance, they are commonly used on dump trucks to raise and lower the dump bed. They are also used to simulate hydraulic cylinders sometimes. They are usually too slow for that application. They work very well by the way. Many people actually prefer the screw drive compared to it's hydraulic counterpart for the dump truck application.

Dan

p.s. - I think my first post directed at you was more friendly and useful than your first post directed at me on Scale4x4... that is... if you are the same person.

[Thorsteenster]

Ah yes, thanks guys. This is good to know as I was thinking of using it for a dump bed.
If anyone knows a build thread or a link with details/pictures etc please post.

Cat, what's your name on Scale? There was a large influx of new users and a bunch of miscategorized posts, so unless it was personal, nothing personal lol.
Really though, no hard feelings I hope.

[fhhhstix]

Here are a couple of screw drives for you.









Video






Video


I hope this helps and all of these screw drives were built by me with some advice from FREDDYGEARDRIVE

Travis

[Thorsteenster]

Thanks, I've been trying to search but stupid Google gives me mostly results for screw driver lol.

[Espeefan]

Screw drives are great. Nice and reliable. Easy to build. Best of all (maybe) no hydraulic leaks! But the one thing I noticed about the screw drives is that the speed at which they raise a dump box is not linear. They lift or lower really fast torwards the bottom of their travel, but then slow down at the middle to top of the lift travel. Not much you can about that, except maybe do a sissors type lift?

[fhhhstix]

My hyd dump does the same thing as it has to start filling the larger sections of the cylinder. Not as dramatic as the screw drive though.

[steamer]

Like playing pool, it's all about the angles. When the slider starts to push it's basicaly trying to push the front end out of the box. Because of the rear hinge, the box has no were to go but up and it does real fast. As the slider goes through the middle and the screw rpm remains the same it looks slower because of the lift angle. Should design a compensator circuit gives max torque at the start, and as the amps start to drop off mid lift, it brings the voltage up to increase the screw rpm making it look more consistent . I'm sure someone on here should be able come up with a circuit. If not, I'll put some thought into it when I get into my dump build.
Rob

[Mustang]

I used the Carson sissor style unit in my King Hauler dump truck. It is very smooth and powerful plus it's speed remains constant. It's designed for their trailer so it takes a bit of modification to fit between Tamiya frame rails but I found it well worth the work.

[Thorsteenster]

Originally Posted by steamer

Like playing pool, it's all about the angles. When the slider starts to push it's basicaly trying to push the front end out of the box. Because of the rear hinge, the box has no were to go but up and it does real fast. As the slider goes through the middle and the screw rpm remains the same it looks slower because of the lift angle. Should design a compensator circuit gives max torque at the start, and as the amps start to drop off mid lift, it brings the voltage up to increase the screw rpm making it look more consistent . I'm sure someone on here should be able come up with a circuit. If not, I'll put some thought into it when I get into my dump build.
Rob

Now that would be sweet, if that's something you can do, just being you thought of it I'm guessing you can, than by all means!

Originally Posted by Mustang

I used the Carson sissor style unit in my King Hauler dump truck. It is very smooth and powerful plus it's speed remains constant. It's designed for their trailer so it takes a bit of modification to fit between Tamiya frame rails but I found it well worth the work.

That's what I'm planning on trying on mine, a scissor lift. Seem you get the best lift for the shortest stroke. I couldn't find it on Carson's site, have a link?

[Mustang]

I have a devil of a time with Carson's site too. I got mine from PMD. It's in their Tamiya accessories section.

[FabOne]

Originally Posted by Mustang

I used the Carson sissor style unit in my King Hauler dump truck. It is very smooth and powerful plus it's speed remains constant. It's designed for their trailer so it takes a bit of modification to fit between Tamiya frame rails but I found it well worth the work.

Mustang -

Do you have any pics or description of the mods you did to your Tamiya frame?

It would be great to see how you mounted your Carson lift.

Thanks in advance -
Terry

[Finster]

I'm not sure if this is entirely possible or not, but instead of an electronic solution what about a mechanical one? What I mean is perhaps a variable pitch screw of some sort. Might be an easier solution, or might not

Just thinking out loud. Anyone have thoughts?

[fhhhstix]

We are on the same page now. Yes with a tractor you run out of room quickly. You could also use small linier actuators like Izzy did on his dozer.

Travis

[Thorsteenster]

Please guys, if you're going to start introducing other than standard screw drives, explain a little what they are!

[fhhhstix]

Thorsteenster a liniear acuator is a smal screwdrive built to look like a cylinder. Here is a pic.



Travis

[Espeefan]

Travis, what's the smallest linear actuator you've found or seen? I've only see the big ones.

[Thorsteenster]

Ahh, nice, I've looked into those before for steering on a crawler. That's the Firgelli, do they work well and worth the money?
I was actually laying out some plans for making something similar using a tiny GRU/motor combo from Pololu.

[fhhhstix]

Espeefan the smallest one I have seen has a 10mm Stroke. Izzy has some on his dozer and rc guyfarms has some on his belly dump pups and they seam to work great.

Travis