Project Squirrel

[Outlaw]

Oh yeah, I remember that now. Those would do excellently. Thank you Nick. I'll have to take a trip to Screwfix at some point for some of those. Would I need an insert, or just drill a hole directly vertical into the plastic? And if so, should the hole be a little smaller so that the screw has a little bit of a bite to it and be able to hold onto the plastic?

[overkill]

You shouldn't need any inserts, just a slightly oversized hole for the screw and an exact or slightly under-size hole for the nut so they don't fall out. Laying out the hole positions is super important so the screws & nuts line up.

[Outlaw]

Slightly oversized for screw, and slightly undersized for bolt. Excellent. Easily a Screwfix job. Much appreciated Nick.

[Roboteernat]

If you pass an Ikea any point, head to the customer services area where you can pick up 'spare fixings' for your ikea stuff.
They have those cross nut things as part of it, and its free...

Disclaimer... please dont abuse that and its for your IKEA stuff........

[Outlaw]

Okay, I'm coming back to this thread once more for a quick question...

So if I remember correctly, the robot has to have an indicator of when it's on, and the supposed easiest way is to use LED lights.

Question is, how would one go about linking said LED's to the robot, when there's 18 volts buzzing through the system? And what LED's would be the best for the situation? As the ones I looked at was extremely low voltage, and I don't want to waste money.

[Outlaw]

Or would it be easier to buy a couple of LED strips and run them in series on the positive side of the battery leading to the ESC? Or is there a better/easier way of linking the LED strip up to show that it's an active robot?

[Roboteernat]

You should get away with using some 24v led strips and hen wire them directly after the removable link and ground so that they are always on when the link is in place.

If you can't find any I'm sure I have a small strip could use?

[Outlaw]

I shall definitely look into that, thank you Nat. But now I have another problem.

Just read the build rules again, and it says I need a fuse for the batteries. Problem is I don't know where to buy and place the fuse and housing in question... any help would be fantastic once again.

The batteries I have are Zippy Compact 35C 2700mAh 5 cell... which means I need a 94.5 amp fuse? Did I calculate that right? Or am I completely off the mark and in need of some simple math lessons?

[daveimi]

Car fuse holder and fuses from Halfords or Maplin are spot on.

[Outlaw]

Thank heavens, just took a look at Halfords and they have a 100 amp fuse on there. You're a saint, David, thank you.

Well, as soon as I figure out how to wire it all up, then I'll be able to do all the soldering and such... just need to make a circuit blueprint so I know what's going on as such. As soon as I got it all worked out on "paper" so to speak, I'll post it up on here and hopefully get feedback on it. But that'll have to be tomorrow, as it's way too late to do anything about it today.

[Roboteernat]

Ignore this

[overkill]

The fuse is there to prevent lipo fires, not protect the electronics. The fuse rating is chosen to be somewhere over the maximum current likely to be drawn by all the ESCs simultaneously but less than the maximum current capacity of the Lipo pack.

The blade car fuses are a bit under rated if your bot has an active weapon, midi size fuses are what many builders use.

[Roboteernat]

sorry i tried to remove my post but didnt see it come up, i didnt think anyone would read it before i got to work, looks like you did

ignore my post, i read rules 7.8.1

[Outlaw]

Okay... now I'm a little confused again... so would it be more logical to get a 100 amp fuse or a 90 amp fuse by that logic? Considering that the battery in question gives out 94.5 amps.

[overkill]

It depends on whether that 94.5A is the continuous or the peak rating. Most packs state both and the peak is usually between 1.5 and two times the continuous rate (if the peak rating is not much more than the continuous rate, its a very good sign of a low quality pack). If that 94.5A is the peak rating, I would go for a lower rated fuse, about half way between the continuous and maximum rates.