BOB FW Series

[sean retro]

After my attempt on proto BOB I'm moving on to my real first FW BOB.

The plan for this one is a 4 wheel drive with a lifter, like S.M.I.D.S.Y. So far this is the lay out for it.
Untitled.png
Just need to get a linear actuator and other parts to go with it. Luckily I got some spare MDF boards to use when I get what I need just to make sure the lay out works and a rough idea on the weight, btw the drill motors I'm using are about 440g.

Knowing my luck when I start, I got the parts I need but not the tools.

[Ocracoke]

Looks good, have you decided on what sort of speed controllers and the shell/bodywork material you are going to use in this?

[sean retro]

The speed controllers I'm using are Botbitz 30a ESC and the body will be made of HDPE about 10-12mm thick.

[Maxamuslead]

The speed controllers I'm using are Botbitz 30a ESC and the body will be made of HDPE about 10-12mm thick.

us the 85a versions as you can power 2 drill motors of 1 speed controller. so you end up 1 for each side.

[Ocracoke]

Sounds OK although I am not sure 15a per wheel is going to be enough... I might potentially advise using a set of TZ85a speed controllers if the BotBitz controllers aren't up to the job.

I'd also look through the build threads of Luna-Tic since this does seem similar in concept if there are any.

[sean retro]

Quick question, does it matter what type of battery it is like Lipo, acid etc. to power the linear actuator?

[Ocracoke]

In short, no. What does matter is how much amperage is being sent to the motor. If there is too much, you'll either burn out the controller or the motor driving the actuator.

[lowndsy]

Anything with an appropriate voltage / ampage will work so the answer is mainly no it doesn't make much difference, but the chemistry will affect obvious things like the weight and dimensions as well as characteristics like power drop off and charging speed so there probably is an "ideal" battery for your requirements.

[sean retro]

Amperage won't be a problem, got some spare fuses what we use in plugs, felling that get a different type of fuse.

[sean retro]

Well I done a bit of soldering for the first time in years.
1st try.
20170927_165357.jpg

2nd try.
20170927_165537.jpg20170927_165602.jpg

Working on the safety link just to see how much practise I need and from the looks of it, I'll need a bit. Also more solder.

[Pinski1]

I've got to say, they all look like dry joints to me, no smooth fillets of solder between the wire and connector solder cups.

You've probably got one of those budget Maplin "30W" soldering irons. Do yourself a favour and invest in a good 100W Antex, they're ~£17 and will solder all connectors with ease.

[sean retro]

It's a 40w that I got from Amazon.

[maddox10]

I agree with Pinski1. Those soldered joints ain't up to spec.

For that kind of work I use a cheap 100W Ironside Soldering iron with the thinnest point I could buy for it.
(for heavier work I have other points, up and including rather heavy copper blocks, electrocoated with nickel)

I'm tempted to buy the 150W brother of it...

I also use custom made teflon clamps to keep the connector pairs in a solid lock. (handy if you can make those yourself from billet or sheet)

Another investment I can advice, heatshrink in the right dimensions. It can hide a lot of sins.
The alternative is hotglue.

[sean retro]

Those few extra watts seem to have made adifference.
20171002_095914.jpg20171002_095934.jpg


Sorry if its looks a bit blurred, but myphone didn't want to focus on it.

[Maxamuslead]

Those few extra watts seem to have made adifference.

Shocking what a "good" iron can do compared to the really awful ones