Help with contactor and motor suppliers please.

[MattLampitt]

Hi everyone. Been a while since last posted. But since then, my kids have grown up a bit, I have a little more time available now and the best bit... Iv moved House and now have a workshop so it’s game on!!

I made a rambot about a year ago ish or something.
i want to put an active weapon on, some sort of spinner I’m thinking. But I don’t want to go the brushless motor and esc route yet.. I wish to use a basic contactor to run a brushed motor. (Seems simpler and less to go wrong)

anyway. I have a question about the signal cables coming from the receiver, and type of contactor I would need.
how can those signal cables be used to switch a contactor? I haven’t measured them yet. But is there 5v between them at some point which can be used to switch the contactor with 5v coil?

Where do people buy there weapon motors from and batteries, iv been using a dismantled 18v 3ah li-on Makita battery for drive but think will need the propper li-P.O. batteries. Is there a few good shops online? I bough my turngey escs from ranglebox but that seems to have shut...

[Roboteernat]

Hi and welcome back!
You will need a suitable esc to run the motor direct from the RX, but as you want to use a contacrot, you will need something that can switch a low voltage output on/off to switch your high voltage contractor/relay.

Have a look at the amp your motor will use if you have it, and calculate the max amps then that can narrow down the switch.
The switch device will convert the RX signal to on off, which can be used to switch the coil or contractor on off.
Using an ESC will allow you to bypass a relay or contractor and give you speed control of your weapon as apposed to bang bang control (off—> max on)
You can program the brushless esc to run brushed motors too. I have programmed a few myself and happy to assist.

Weapon motors can be sourced from hobbyking, or eBay for weapon brushless and brushed respectively.

Batteries can also be bought from hobbyking, but as your talking about max it’s battery packs I assume it’s a featherweight your building, so something like a 5s or 6s, I use 4s, 2800mah or 3000mah will be fine for spinning weapons if a little too high, I use 3200 and 2800 for my axe bot and it doesn’t run low.
Optipower are also battery supplies I think that’s what they are called and as a FRa member, they have discounts.

Ranglebox stopped selling the tz85a as that particular model esc has been discontinued. I use these on my bot and have programmed th5em myself.

Motors, people also use Argos drill motors as a basic start. I sell motor mounts for these too shameful plug!

[MattLampitt]

Yeah it’s a feather. My idea was to not use a esc for weapon at all if I could get away with it . I didn’t know if there was a tx controlled on/off switch type thing I could use instead, either to switch a coil inside a contactor or the actual motor it’s self (depending on current rating) I’m pretty new to the remote controll side of things.

im gutted they stopped the tz85a. They seemed awesome, I purchased 2 from botbotz that were altered to run brushed And they work a treat. When you say people use drill motors?? You mean for weapon aswell?

Also, while I’m firing questions off, Is it a a huge necessity to have li-P.O. batteries?? Reason I ask is a have about 10 3ah li-ion batteries lying around, one could easily be adapted to do drive and the other to do weapon motor? I also have chargers too. So not sure whether to go to the expense of buying some lipo’s when I have these.

Has anyone ever used a 18v cordless ripsaw motor for weapon or drive? They are beefy!

[Retroman]

You don't need to use LiPo batteries, they're popular because of their power to weight ratio.

I'm also pretty sure there's something called a 'Battle switch' for the heavies, I don't see why you couldn't use a relay for a feather, just be careful with the draw, a relay will click 'ON' and draw a good lump of current from the off, an ESC can at least accelerate more slowly to avoid stall draw scenarios, but this is only the thoughts of a newbie, maybe the practice works different to my understanding of the theory.

As for the ripsaw motor, every component has it's pioneer, those saws have some mega chops, could be an interesting result for a spinner.

[typhoon_driver]

This is what you want to interface between the receiver and a larger contactor. I've used these in every machine I've built and haven't had one fail on me.

https://www.technobotsonline.com/pol...vdc-relay.html

[MattLampitt]

Yessss Gary.. you legend., that’s exatly what I wanted cheers man..
iv ordered something similar that I found on eBay but I much prefer that one for its volt free output. Think the one I found used the 5v from the BAC just on or off so really thanks for that.. Iv spent my night butchering an old ripsaw. Attached a 2kg dumbbell to it and span it up to measure startup and run current and times etc. In a safe way obviously. Lol. Fun times haha