Extending a Hex Shaft?

[AllenGregoryIV]

Does anyone know of a simple (cheap) way to extend a hex shaft? We have a need to couple the end of a Versaplanetary to a longer hex shaft but haven't been able to find a cheap 1/2" hex shaft collar.

Any suggestions for teams without a lathe or a mill?

[Akash Rastogi]

Know a local team with a hex broach?

[Madison]

It might not be pretty, but you could probably use a modified AM Hex Hub (http://www.andymark.com/product-p/am-0096.htm).

[steelerborn]

http://www.mcmaster.com/#male-female...ndoffs/=l9l4gb

Maybe one of these?
The issue would be you would need to tap the end of the output shaft, and you would need that to be in line with the axis of the shaft.

[AllenGregoryIV]

Originally Posted by Akash Rastogi

Know a local team with a hex broach?

Not that I know of, but probably. With all the hex stuff now we should probably get one soon, but we would have to buy a bigger arbor press for that as well.

Originally Posted by Madison

It might not be pretty, but you could probably use a modified AM Hex Hub (http://www.andymark.com/product-p/am-0096.htm).

That was my first thought and was hoping there was another way to do it.

[Aren_Hill]

Originally Posted by AllenGregoryIV

Does anyone know of a simple (cheap) way to extend a hex shaft? We have a need to couple the end of a Versaplanetary to a longer hex shaft but haven't been able to find a cheap 1/2" hex shaft collar.

Any suggestions for teams without a lathe or a mill?

What diameter clearance do you have? you could get quite creative with bolting some hex hubs together with standoffs.

possibly take a tube with a close enough inner diameter and shoot two pins through it to retain the shafts?

The VersaPlanetary 1/2" hex output also has a 1/4-20 hole in the end, you could possibly tap the end of the other piece of hex shaft, take a short piece of threaded rod, twist the two together then take a 1/2" Hex shaft collar on the outside to overlap the two which would transfer the torque.

Just spitballin here

[steelerborn]

I did not realize that versa planetary gearboxes came with a hole on the end.
Just use the male end half inch hex standoffs from mcmaster I posted the link earlier.

[craigboez]

You can always throw away the shaft that came with the gearbox and make you own longer shaft out of some hex stock. We have done this a few times with planetary gearboxes. It will probably involve turning one end round, adding a snap ring groove, and milling some flats. This is very doable with a manual mill and lathe.

[androb4]

Originally Posted by craigboez

You can always throw away the shaft that came with the gearbox and make you own longer shaft out of some hex stock. We have done this a few times with planetary gearboxes. It will probably involve turning one end round, adding a snap ring groove, and milling some flats. This is very doable with a manual mill and lathe.

Originally Posted by AllenGregoryIV

Any suggestions for teams without a lathe or a mill?

.
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[pfreivald]

Originally Posted by AllenGregoryIV

Does anyone know of a simple (cheap) way to extend a hex shaft? We have a need to couple the end of a Versaplanetary to a longer hex shaft but haven't been able to find a cheap 1/2" hex shaft collar.

Any suggestions for teams without a lathe or a mill?

Is there a team nearby with a lathe or mill that would be willing to make you a coupler (or a longer output shaft)?

For future years, I highly, highly suggest getting a small benchtop lathe and mill -- all told they'll run you close to $2K, and problems like these just evaporate.

[Aren_Hill]

Originally Posted by craigboez

You can always throw away the shaft that came with the gearbox and make you own longer shaft out of some hex stock. We have done this a few times with planetary gearboxes. It will probably involve turning one end round, adding a snap ring groove, and milling some flats. This is very doable with a manual mill and lathe.

VersaPlanetary gearboxes have a spline on the output shaft with much higher torque carrying capability than the flats of other gearbox shafts.
Making your own spline would require a lot of effort

[AllenGregoryIV]

Originally Posted by pfreivald

Is there a team nearby with a lathe or mill that would be willing to make you a coupler (or a longer output shaft)?

For future years, I highly, highly suggest getting a small benchtop lathe and mill -- all told they'll run you close to $2K, and problems like these just evaporate.

It's not a money issue we have extremely limited space. I know your mobile cart solution and if we even had a closet I would do that but we don't. We also don't have anyone who knows how to use a lathe or a mill (outside of my extremely limited experience).

[pfreivald]

Originally Posted by AllenGregoryIV

It's not a money issue we have extremely limited space. I know your mobile cart solution and if we even had a closet I would do that but we don't. We also don't have anyone who knows how to use a lathe or a mill (outside of my extremely limited experience).

Wow. The table's about the area of two-and-a-half FIRST totes put end-to-end, and holds most of our hardware in addition to the machines (which I'm certain *someone* would help you learn how to use!) I can't imagine even trying to build a robot without enough space to store something like that.

[AllenGregoryIV]

Originally Posted by pfreivald

Wow. The table's about the area of two-and-a-half FIRST totes put end-to-end, and holds most of our hardware in addition to the machines (which I'm certain *someone* would help you learn how to use!) I can't imagine even trying to build a robot without enough space to store something like that.

Maybe if it's that small, but we share space with other things in the school. So we have space but we have to clean up most nights.

[craigboez]

Originally Posted by Aren_Hill

VersaPlanetary gearboxes have a spline on the output shaft with much higher torque carrying capability than the flats of other gearbox shafts.
Making your own spline would require a lot of effort

I hadn't bothered to look at the inner workings of the VersaPlanetary until now. That is quite a spline. Since we a) never use planetaries for high torque applications and b) like to customize the output shaft I don't see us investing in these any time soon.

So as a follow up to my original suggestion, first buy a Banebots P60 and then DIY the output shaft.