I've been reading a threaqd in the 3-d section, and there is a thread about a plane that runs off a cd-rom motor. Lot's of people have posted about their own Cd-rom motors, and almost all have said how much thrust it produced eg: 300g.

I am trying to figure out how to find out the amount of thrust. Do you need to attach a propeller and hang the motor from a set of scales? Can someone please help me find out how to find the amount thrust produced?

Beep.

If you do a search for motor test stands you will see the contraptions that are used to measure thrust. Some of the motor gurus have posted pics and diagrams of the tools they use.

That is what you need - works great!
http://slofly.com/cart/index.php?cPath=27_139

hans

Thanks, very clever. Do you think that i could build one myself, or would the wooden arms have to be an exact length so as to not give mechanical advantage?

Try this link with pictures of the "new" Dick Hanson designed stand: look at Post #25 on.

http://www.rcgroups.com/forums/showt...thrust+checker

I've attached some additional photos

Cheers, Phil

Phil neither link works.

Charles

Another approach is to measure the RPM, then use a thrust calculator, such as the one at GoBrushless.com. If your prop is one of the 50+ props available in the calculator, the calculated thrust is reasonably accurate.

Actual measurement on a thrust stand is preferred, but for those of us who still haven't built one, the calculator is a nice tool. Thanks to JayC, MorrisM, and Dr. Kiwi for creating it.

- Jeff

Originally Posted by everydayflyer

Phil neither link works.

Charles

Sorry Charles - Try the edited version now.

Originally Posted by galloping gimp

Another approach is to measure the RPM, then use a thrust calculator, such as the one at GoBrushless.com. If your prop is one of the 50+ props available in the calculator, the calculated thrust is reasonably accurate.

Actual measurement on a thrust stand is preferred, but for those of us who still haven't built one, the calculator is a nice tool. Thanks to JayC, MorrisM, and Dr. Kiwi for creating it.

- Jeff

I've mentioned this elsewhere, but I believe the calculated thrust outputs are a bit lower than they should be (old stand v. new stand!). We should update the data base.

Originally Posted by Dr Kiwi

I've mentioned this elsewhere, but I believe the calculated thrust outputs are a bit lower than they should be (old stand v. new stand!). We should update the data base.

Phil, If you have new data from the new stand please email it to Jay and me. Maybe you even have some new props to add

I really appreciate all the time you have spent collecting prop data... thanks much

Morris

PS - Send to Rod(badcockr) also. His spreadsheet is nice.