Possibly useful - 33:1 gearbox

Harbor Freight has a hand-cranked lugnut remover with a 33:1 ratio on sale for $16.99. It’s a little heavy, but it has an aluminum case and you could throw away the steel handle and pivot and cut off part of the mounting arm. It’s sloppy, but might be very useful for a high torque, low-speed application like raising an arm, aiming a device or raising and lowering a retractable caster wheel. Item # 93645. Just a thought.



Wow… although I’ve never thought of Harbor Freight to sell durable products. My hammer from the dollar store lasted longer than the one that I got from Harbor Freight.

Although a 33:1 ratio is kinda out there, it would work very nice to raise an arm.

Edit: The ratio to raise and lower my Vex robot arm is 7:1 and it moves extremely slow. So I wonder how slow that ratio would be, but then again it depends on the motor you attach it to. And then you could put it to be 1:33. Super fast. Not extremely useful in FIRST but maybe in a combat robot. LOL.

yes but the vex motors are gear motors and have a very big reduction in the case of the motors, yes hf is bad unsealed bearings in a water pump

Do you have the complete item number for the $16.99 sale price? It comes up at $29.99 on the HF website and the sale price in the latest catalog I have it $19.99. I am heading to HF sometime this weekend and if they have them I might pick one up for the $16.99 sale price and open it up to see how it looks inside. The local store will match the $16.99 sale price if I can print it out from the website.

The item is in a printed flyer I just received in the mail. Item 933645 is all it says. The local store should have a bunch of the same sale flyers. Sale ends 9/25. You could call a store and check price/availability. As I say, these are sloppy and definitely something for a slow speed actuator or similar task. If someone needs a 15:1 gearbox for a reasonable price, check this: http://www.surpluscenter.com/item.asp?UID=2006090210131439&item=28-1049&catname=powerTrans
it’s for a lawnmower, so it should handle some power. A bit heavy unless you cut off a lot of the shaft.

Harbor Freight also has digital voltmeters on sale for $3.00 Great for loaning out to people who check voltage using the resistance range :slight_smile:

I got one at my local HF store for $16.99. It didn’t appear on the sale flyer (or at least neither the store clerk nor I could find it there) but the sale price did come up when they scanned it at the register.

Does anyone have photos of the gearing inside?

It’s $19.99 in the Aug sale flyer, $16.99 in the Sept sale flyer. There might be a picture or gear description in the manual (on line).

Check the on-line manual at Harbor Freight. Perhaps it has an exploded parts diagram. My Acrobat reader decided not to work at the moment…

Others are selling this as the “EZ-Lug” for $50-$60. I wonder if there’s any difference in quality?

33:1 on a CIM is about 2.5 rev/sec. Perfect for an arm if you add in a small reduction before hand. But it would seem like a big modification perhaps.

You might be able to use it without reduction by using some sort of cam arrangement - depends on how much you want to raise it.

I did see the exploded parts diagram of this. There’s an internally toothed annular gear around the outside, and what appears to be two inner gears with some eccentric shaft. It’s hard to see from the drawing just what is going on.

Even better. $14.99 http://www.harborfreight.com/cpi/emails/36/RetailB/images/17.jpg

Supposedly the coupon is good Sept 15-21

Is that only good in Pittsburgh? I just noticed the label in the top corner.

<EDIT> Wow, I feel dumb.</EDIT>

There’s a picture and more discussion here: http://www.chiefdelphi.com/forums/showthread.php?t=49073

Also here: http://www.chiefdelphi.com/forums/showthread.php?t=49064

One thread is about the innards of the torque multiplier, another is about a possible application.