Picture request: HW drivetrains

[daveimi]

I wondered if you peoples would be happy for me to have a quick look at the gearboxes you use in your modernish heavies? Any info on motor model, gear ratio and wheel size v. much appreciated. Trying to get this sorted before bodyshell shows up next month eek.

Edit: Also interested in info on chain pitches and sources of sprokets if anyone uses that style of drive.

[team_mute]

Here a pick of Bonk's drive train


Were using the AmpFlow A40-300 Motor with 4" wheels

[teamshock]

Here is what we have in Manta.

Bosch 750 on a 4.5:1 reduction (its around that can't remember for sure). There are 2 main changes from this photo- it now has 17mm shafts instead of 15mm and it runs on 160mm wheels not 125mm

[daveimi]

I was looking around at everyone's build diaries and noticed that there's quite a few people using this style of gearbox (i.e. a pair of plates with the gearing and wheels sandwiched between them). Do people make their own or is there anyone on the forum that will CNC me some if I were to get some motors and ask very nicely?

[maddox10]

The originals of those gearboxes are the ones in Dantomkia. Mike lambert was the first to make those.

Jeroen/Kos of Tough As Nails made a few others ont he same principle. The ones in Gravity 3 were a set of those.

And he can mill more of those, but let me warn you, it isn't cheap. Just buying the gears does cost a bit.

[marco]

this is what Jeroen made for me for Brutus
https://picasaweb.google.com/Jeroenvdlo/GearboxMarco

[shakesc]

Those are really nice drive units

[tough_as_nails]

Thank you.

[daveimi]

Ok...looks as though chain driven is the future.

[Niels - Team K.a.L.M.]

?

Chains are more like old school...

People went from chains to gears because the chains kept running of the sprockets in battle.
Don't get me wrong, they still are usefull and require less precision to work but the drawbacks are bigger.

[daveimi]

Ok. Is it possible to fabricate cheap gearboxes using say pre-made Mod 2 gears?

[Gabe01]

I've used chains on three heavyweight robots and they always held up

[geeza]

Both gears and chains if done properly will work fine. And yes you can make gearboxes cheapish.

[maddox10]

Yes, that is perfectly possible, if you can buy the gears cheap. Know your way with bronze bushings and have a fair hand with a pillardrill and a good eye for marking the holes.

For a heavy gearbox, not to expensive I would use lasercut 5mm steel plates 15 and/or 20mm steel axles and bronze bushings.

In Bullfrog there is a version of that. Unfortunatly, we used custom made ali gears to get the weight down, and that blew the "cheap" to "barely affordable".

[daveimi]

Gosh those motors look pretty meaty! I will need to work out wheel size, desired speed, motor rpm and gear accordingly. Thank you for the info on everything, when people have used chains is there a pitch that's common on heavies or are they all different? Oh and do people ever use tensioners or if the tensions right are they unnecessary?