Allowable motors early info

[Gdeaver]

As a summer project we are going to look for mass produced off the shelf alternative gear boxes. Mainly power tool and automotive units. Every one should be familiar with the Devault hack. We are looking to do the same with others. I found a seat positioning motor gear box that looks to be adaptable to a RS540 - RS550 motor. Well constructed unit and looks like a plate and pinion change is all that is needed. Also, the mini cordless drivers look promising. We used 5 banesbot gear boxes this year. While we did not break any , there were to many problems, shipping delays and substantial cost. Got to be something better out there. I found some surplus precision servo motor gear boxes online for 33$. List price is around 310$. Could we account for them at 33$ on the BOM?

[AllenGregoryIV]

Gdeaver if you do find gearboxes that work it would be great if you could post them for the rest of the community. I worked with Joe P when he was writing the Nothing But DeWalt paper and I know how much it helped the community. One thing you might also want to look into is gearboxes from power wheels type toys like the fisher-price gearbox. I believe that 1114 had great success in using different gears from those gearboxes to quickly make custom gearboxes for their robot this year. I did some hunting in the past and found a couple that use the 775 can motors I never bought any to test but this could be a interesting option and they were under $30.

[Timz3082]

Originally Posted by AllenGregoryIV

Gdeaver if you do find gearboxes that work it would be great if you could post them for the rest of the community. I worked with Joe P when he was writing the Nothing But DeWalt paper and I know how much it helped the community. One thing you might also want to look into is gearboxes from power wheels type toys like the fisher-price gearbox. I believe that 1114 had great success in using different gears from those gearboxes to quickly make custom gearboxes for their robot this year. I did some hunting in the past and found a couple that use the 775 can motors I never bought any to test but this could be a interesting option and they were under $30.

It looks like I found something great! http://kamocat.com/robot/planetary.php

This site has a comprehensive drill gearbox modification how to.

[Dale]

A lot of the Banebots issue is they way they build every transmission to order. I'm wondering if they could instead give teams the option of buying the stages and housing in kit form so we could assemble them ourselves. Usually Banebots shipped in a day or two anything they didn't have to assemble.

You can do this now by ordering all the parts seperately but that's pretty tedious.

[Kevin Sevcik]

Originally Posted by Dale

A lot of the Banebots issue is they way they build every transmission to order. I'm wondering if they could instead give teams the option of buying the stages and housing in kit form so we could assemble them ourselves. Usually Banebots shipped in a day or two anything they didn't have to assemble.

You can do this now by ordering all the parts seperately but that's pretty tedious.

This. When we ordered replacement/upgrade parts for our P60s, we always got them with a good leadtime. This in the midst of the 1 month P60 backlog.

I'm convinced that BB's problem isn't inventory or part supply, but assembly time. They've so far insisted on shipping their gearboxes "pre-assembled" with no grease. So you have to disassemble them anyways to grease them. Meanwhile, they have to have people spend something like 15 min or more per gearbox assembling it, leading to ridiculous leadtimes when they get hit with orders for thousands of gearboxes.

If they simply offered an unassembled kit form of the P60s, everyone would be happier. They'd save time and labor costs. We'd get gearboxes faster. And there wouldn't be this pointless wasted time of assembling gearboxes that will just need to be disassembled again. They could even make things easier for themselves by packaging things in complete planetary stages. A bag for a 5:1 to 5:1 stage, a bag for a 5:1 to 4:1 stage, and a bag for a 4:1 to 4:1 stage, and bags for the 5:1 and 4:1 output stages. Shipping an order would be a simple as grabbing the appropriate stages and tossing them into a box with the correct ring gear, mounting block, and output shaft. And then you fire it off to another satisfied customer. The only real obstacle to this is writing some assembly instructions so people know what order the stages go in.

[jee7s]

Originally Posted by Kevin Sevcik

If they simply offered an unassembled kit form of the P60s, everyone would be happier. They'd save time and labor costs. We'd get gearboxes faster. And there wouldn't be this pointless wasted time of assembling gearboxes that will just need to be disassembled again.

Sage advice. I hope some operations people from Banebots are listening.

I do recall at least a few teams buying P80 gearboxes as stacks of replacement parts that they later assembled on their own. (At least one such team posted a picture of their pile o' parts here on CD.) While I can't be sure of their motivations, I'd assume the absurd lead times that developed brought them to this solution.

If any team does decide they 'need' to stock gearboxes, I'd definitely do it in unassembled parts. That way, you can pick and choose to get the gear ratio you need. Also, when the motors change (and yes, as noted, they change quite frequently) you don't end up with a pile of spoiled inventory. While it's a pain to list out the BOM for each gearbox yourself, it's just paperwork. You could purchase those parts now for either the P80 or P60 that Banebots offers. If a motor changes next year, you should just have to buy a new motor plate for the gearbox to get everything working nicely.

Even if the parts won't be put in inventory, there's still something to be said for buying unassembled gearboxes. You get exactly what you need (shaft length and all). You avoid a greasy mess (if you had naively purchased a greased P80, for example). And, you get a great teaching tool for how gearboxes work. My team is seriously considering this approach going forward.