Small problem - connecting servo wheel to smooth-faced metal wheel?

[stevem]

Hello,

I've got a vintage airspeed indicator for my Lockheed T-33 cockpit project.

My servo wheel needs to turn a smooth-faced metal wheel in the instrument. But, I cannot think of a way to mechanically connect the servo wheel to the smooth-faced metal wheel.

See attached pic.

Can anyone make any suggestions on how I can mechanically link them? Thank you!

http://www.mycockpit.org/forums/attachment.php?attachmentid=11220&stc=1

[hyamesto]

Maybe you can glue a spur gear to the smooth-faced wheel or in his axis, and replace the servo wheel with another spur gear. Both spur gear, (smooth-faced wheel and servo wheel) must be paired.
You can play with gears ratios to obtain more or less turns.
Or use this:

http://www.mycockpit.org/forums/attachment.php?attachmentid=11222&stc=1

http://www.ebay.com/itm/4pcs-25-3-2-4mm-Rubber-Car-Tire-Toy-Pulley-Wheels-Model-Robot-Part-for-DIY-/371407016611#shpCntId

You can use a spring to keep the friction.

Regards.
Horacio.

[stevem]

Hi Horacio,

That's a good idea… not sure why that didn't occur to me! I'll see if I can find an approximately 1" geared wheel that I can attach to that smooth-faced wheel on the instrument. Thanks -- I'll see what I can dig up!

Steve

[hyamesto]

You can make your own geared wheel. Use some cad to drawing the gear, and make an acrylic laser-cut gears.

Horacio.

[stevem]

Hi Horacio,

I'd love to have laser-cut things, but I don't have access to laser-cutting equipment. I've seen the new Glowforge 3D laser printer, but it's not shipping yet… and, it starts at over $2,000. Other than that, I have no idea where to get things laser-cut inexpensively.

[hyamesto]

Steve:
You don´t need to buy a laser-cutting.
You can send a .cdr file (coreldraw) to a laser-cutting service. (I have seen in other post that you know how to use Coreldraw)

In your city (Milwaukee) you have a service:

http://www.lasercuttinginc.us/

You can ask for prices.

That´s what i do in my town.

Some of my laser-cut gears...
http://www.mycockpit.org/forums/attachment.php?attachmentid=11223&stc=1

Here with some Auto-slot gears and pinions to compare (another source of good spur gears)

http://www.mycockpit.org/forums/attachment.php?attachmentid=11224&stc=1

Other links in Milwaukee (source of Auto-slot gears, and other useful things)

http://www.lucky-bobs-slot-cars.com/
http://www.hoslotcarracing.com/


If you need some info to draw the gears or others parts, i can help you.

Regards.
Horacio.

[stevem]

Hi Horacio,

I'm thrilled to meet a fellow Corel Draw user! Your gears look great. I think Corel Draw is a great program -- I've been using it since 1989. Thank you for offering to help (I'm willing to help anyone out there as well, if they need Corel Draw drawings).

As a coincidence, I called Laser Cutting Inc. last week, and they said that they don't do small jobs like that. Too bad. But, thanks for the other links -- I'll check those out.

I did find some gears on eBay, which I ordered. So, I think my airspeed indicator will slowly take shape.

My biggest challenge now is building parts to mount the servo motor(s) to the instrument chassis. I'm looking into the MicroLux Mini Scroll Saw ( http://www.micromark.com/microlux-mini-scroll-saw-for-hobby-use,7114.html ). Maybe I can cut the plastic mounting pieces that I need. I'll let you know. Thanks!

[hyamesto]

I found a good place for you......

http://milwaukeemakerspace.org/

If I could have a place like this in my city.......:roll:
Laser-cut, 3D printing, etc....

Anyway, i think it is a great resource for you.

Regards.
Horacio.

[stevem]

Wow! I've never heard of Milwaukee Maker Space. I will definitely check them out! I'm amazed that you found this. We've lived in the Milwaukee area since 1998, and we are constantly discovering new bars, restaurants, venues, concerts, festivals, and more in this area. And now, a Maker Space -- how cool! Our winters might be brutal here (right now it's 17 degrees F), but our summers are fantastic. Still, I'd trade that beautiful weather of yours in Argentina any day! : ) Thanks again, Horacio.