Spinning a steel pipe - pulley or sprocket connection

[stubious]

I'm attaching a projector screen to a 2" steel tube, held by pillow block bearings. This will allow me to roll the screen up when not in use. The tube will be high enough that I can't manually roll it without standing on a ladder or chair. I may eventually automate the rolling/unrolling with a motor, but let's assume that's out of scope for now.

I'm trying to figure out how to spin the tube while standing on the ground. I'm thinking I could attach a sprocket or timing pulley to the end of the steel tube, then manually pull a timing belt or chain (much like manual blinds). The question is how to best attach a sprocket or timing pulley to the tube.

In my research, I've found things like a taper lock bush that would do the trick, though massive overkill for this project. And the affordable ones require a key for the connection - which requires an offsetting cut out of the tube, as they are seemingly used mostly for solid metal pipes rather than the hollow tube I'lll be using. Now, maybe the key isn't required for the limited torque I'd be using here and that could work.

I don't have welding equipment or skills, so that's out of the question. I'm guessing there is a more obvious solution here - but not one I've come across.

Ideas appreciated!

 

[freddiemercurystwin]

Why don't you just use a pull down projector screen?

 

[stubious]

It is actually an impact screen for a golf simulator. So without spending thousands of pounds, you can't get a pre-made one!

 

[Burnerman]

Taper lock bushes are absolutely superb - probably the best type would hold a sprocket rather than a belt - after all, you can buy chain at any length, unlike a belt.
As you say, it will be a bit overkill and certainly industrial but if you can live with that it would sort your project immediately.
I use a firm called Eriks when I need this sort of power transmission.
John

 

[stubious]

Thanks John - all the affordable taper locks I'm seeing require a 'key' - the metal piece that fits into a groove in the pipe. I'm guessing for my use case, the lack of a key wouldn't actually be a problem since I'm not trying to spin this thin at machining speed? Just wondering if the key is a must have to get any grip?

 

[Burnerman]

No, they get a ferocious grip without a key....more than enough for your project anyway!
John

 

[stubious]

Amazing, exactly what I needed, thanks so much!

 

[jj4091]

Not sure of the cost of fitting what you propose is, but Somfy or other tubular motors are not that expensive for the low loading it sounds like you require & you could run it of an extension lead until you could afford to have a proper supply fitted near to the motor.

 

[conny]

As Burnerman says, taper-lock would be ideal because you can position it anywhere along the tube. Don't worry about crushing the tube, because you won't! They are designed to put equal pressure all around the pipe/tube and it is extremely difficult to compress to distortion.
ERIKS is a very good reputable company for these fittings, you may find them a bit pricey compared to a hardware store but that is because they are top quality to industry standard. There should be a local distribution centre near you but simply google to find where as they are usually on industrial parks, not retail parks. They also do orders by post.

 

[stubious]

Not sure of the cost of fitting what you propose is, but Somfy or other tubular motors are not that expensive for the low loading it sounds like you require & you could run it of an extension lead until you could afford to have a proper supply fitted near to the motor.

Thanks - have looked around at tubular motors and with a smaller diameter pipe requiring a higher torque motor - the gear-based approach will probably be half (or even less) of the motorised approach. We're not talking huge amounts either way. Depending on how annoying the 'chair + hand' method is and how much I'm using it, I may go the gear route or jump straight to the more expensive, but frankly nicer, motor route. And I do have an outlet close by, so could run it off a lead and avoid the electrician fees.

Glad to see I've got a few options!