Scorpion Motors: Questions and Answers.... - Page 788 - RC Groups
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Jun 07, 2011, 04:57 PM
The "Foaminator"
mikeruth's Avatar
Originally Posted by AdamChicago
Thanks Mike! Anything I can salavage is a huge help to the wallet.

Do know if those are standard bearings I can buy locally or do I have to order them from Scorpion?
Oh and to be on the safe side, take it appart and see if itt has three or two bearings, there was a runnig change.

there metric so who knows, you might find a local supplier with a decent price. I haven't been that lucky so I order from Scorpion.

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Jun 08, 2011, 04:16 PM
Whats the wrst that can happn?
AdamChicago's Avatar
Thank you very much!! ...they're on the way
Jun 08, 2011, 06:23 PM
The "Foaminator"
mikeruth's Avatar
Originally Posted by AdamChicago
Thank you very much!! ...they're on the way
My pleasure,.

Mike r
Jun 09, 2011, 04:28 AM
Watts up ?
OzparkPilot's Avatar
Hi Guys - Need advice on next project - Its a 59` Gee Bee R3 !! I am thinking as I need atleast 1000 Watts. I plane to run it on 5s 4000 40c and 3700 30c. 14x7 APC E prop looks right ? any help would be great. Ideally, I want 1400 Watts.
Jun 09, 2011, 05:01 AM
Registered User
Peter M's Avatar
I think this is more like what you need: and run a bit more pitch.

I can even static run one of my 10 turn Hyperion ZS 4025 equivalents on 5 cells and a 14 x 7E if you want an exact current draw and wattage to give you a basis to work with.
Last edited by Peter M; Jun 09, 2011 at 05:09 AM.
Jun 09, 2011, 06:25 AM
Watts up ?
OzparkPilot's Avatar
I like it ;-)) Did not even look at the 25 size. Might be a little heavy... But then, the R3 is meant to be tail heavy so this might work. Thanks Pete
Jun 09, 2011, 07:48 AM
Registered User
Peter M's Avatar
Are you thinking about converting this model?

If that's the case I think maybe you'll want more than 1400 watts to make it perform like it looks!

Are you sure you're limited to a 14 inch prop and what weight do you expect itto be RTF without battery and motor?
Jun 09, 2011, 05:51 PM
Innov8tive's Avatar

I'm Back!

Hello everyone! It has been quite a while since I posted any replies on this site. We have been extremely busy here working on our new website, going to trade show, and many other activities that have taken up most of my time for the past few months. I am going to set aside some time each day to come back and answer questions regarding Scorpion products posted on this thread.

I am going back a page on the thread to April 9th, and will post replies to as many questions as I can until I get caught back up wit the current posts. Since this will be a lengthy process, I will answer the questions in multiple posts, so each one does not get too long.

Here we go!

SII-3020-890 Shaft Adjustment

Originally Posted by Mwellendorf18
Im wondering what it takes to move the shaft in this motor forward? Allen sizes and any special technique

The Scorpion motor shafts are a press fit into the motor housing, so even after you loosen the set-screws, you need a press to move the shaft. I put together a vieo that shows the correct way to change a shaft in a Scorpion Motor, and this is a good reference to see the proper way to do it. This video can be viewed on YouTube at the following link.

How to Change a Shaft in a Scorpion Motor by Innov8tive Designs (11 min 30 sec)

There are flat spots on the shaft where the set screws go, so if you move the shaft, you will need to either extend the current flats or gind new ones on teh shaft in the new locations. We have another video that shows the correct procedure for grinding a flat on a motor shaft, and it can be seen at this location:

How to Grind a Flat on a Motor Shaft by Innov8tive Designs (8 min 35 sec)

Depending on when the motor was built, you may need to use either a 1.5mm or 2.0mm hex allen wrench to remove the set screws.

Originally Posted by Tommy D
Hey Guys

Looking for some help Diagnosing a S 4020-12 motor.

It has sat since November of last year as I did not flying in the winter. Saturday was warm enough to fly so off to the field I went.

First clue something was wrong was when I connected the battery the Castle ESC's cell beep count was very faint. Then when I moved the throttle the motor would cog forward and backwards but never start.

I checked the CC80 by connecting another outrunner to it. It ran fine.

The only check I made on the S 4020-12 was with an ohm meter. Two of the wires show a varying resistance of .95K and 1.0K depending how I flex their leads out the motor. The remaining leads show 0 ohm resistance when checked against each other.

Physically the motor looks brand new, smooth bearings and no burning of the windings.

Purchased New from Todds Models Late 2009 am I SOL?


Tommy D

<P.S. would it be worthwhile to re-solder the connectors back on the motor>? I ponder this as it seems the movement of the wires going inside the motor varries the resistance so I didn't bother trying that.
Whenever a motor just quivers back and forth when power is applied, it means that you are only getting power on 2 of the 3 phases. In brushless motors, power is applied between phase A and Phase B, and the motor will rotate to the next magnet. Then power is applied to phase B and C, and the motor rotates again to the next magnet. Then power is applied to phase C and A and the motor again rotates to teh next magnet. Then the process repeats again through another phase cycle. When one phase loses connection, the motor will go forward one magnet, then sit still for a cycle, then back up on magnet, then go forward one magnet. When this happens, the motor just quivers back and forth instead of rotating.

The problem with this is that when the motor does not rotate, to the speed controller it appears as a dead short, and will draw a ton of current if you advance the power to full throttle. This will cause the motor, speed controller or both burn up if it is left in this condition for more than a few seconds.

There are a few different causes for an intermittant connection. The most common reason is a bad or cold solder joint on one of the bullet connectors, either on the motor or ESC. Recently I have seen a lot of spped controllers stop working because of a cold solder joint on one of the bullet connectors that the user installed themselves. I must digress at this point and give a bit of history on soldering to explain what is going on here.

Virtually all of the speed controllers that are being manufactured today are done so under the "ROHS" act, which stands for Reduction Of Harmful Substances. In electronics, this means that the products are manufactured so they are free from heavy metal contaminants such as lead and mercury. For speed controllers, this meand that the solder used to assemble the components and solder on the lead wires contains no lead. This solder melts at a higher temperature than conventional tin-lead solder does, and this can cause problems when the two solders are mixed.

Typically, speed controllers come with the lead wires pre-tinned from the factory to prevent fraying of the wire strands. Most people figure that since they are pre-tinned, they are ready to go. Many people will simply slide a bullet connector onto the end of a ESC lead wire and then heat up the bullet connector with a soldering iron until it gets hot enough for solder to start melting. Then they add the solder until it fills in around the wire and pull away the soldering iron. When a connector is soldered this way, in many cases, the wire itself does not get hot enough for the solder on it to melt, since the ROHS solder melts at a hotter temperature than the typical solder that the modelers are using. In the end, you get a wire that is embedded in a glob of solder on the end of the bullet connector that has a mechanical connection only, and little or no actual electrical connection.

A solder joint done this way my work OK for a while, but after you run current through it for a while, and throw in a little vibration, the solder joint will fail. When this happens, the motor locks up, and if it is above half throttle, about 2-3 seconds later either the motor or ESC burns up. I have gotten quite a few speed controllers back from people recently that said everything was running fine, and they were only pulling about 2/3 of the rated current through the speed controller, when suddenly on the 20th flight of a model, the speed controller blows up. They send the speed controller back to us under warranty, and when I get it, I wiggle one of the bullet connectors and it pulls right off the wire in my hand.

When I call the customer and tell them that a bad solder joint was the cause of their speed controller failure, they usually tell me that they have been soldering for 20 years, and there is no way a bad solder joint caused the ESC to fail. It happens all the time, because many of the "Old Time Solderers" are not familiar with the new ROHS typs solders and do not take the proper steps to get a good solder joint.

Now sometimes, there will be a cold solder joint on the motor as well. It is rare, but when someone sits at a bench all day at the factory, and solders several hundred bullet connectors in a day, every once in a while they will get a bad one. So if you check the ESC bullets and the problem still exists, you can check the motor bullets as well.

Hopefully that will get you going!

That was a long one, so I will stop there for now and start another post.

See you back in a few!

Jun 09, 2011, 06:06 PM
The "Foaminator"
mikeruth's Avatar
Lucien my freind, that is an EXCELENT post especialy concerning the difference in tempature required for the new ROHS solder.

Always appreciate you insight and comments.

I'm one of the old guys "been soldering for 20 years etc" I had recently noticed it seemed to be taking more heat to get a good joint.

Mike Rutherford.
Jun 10, 2011, 09:39 PM
daedalusrobert's Avatar
Sorry to see the price your motors but can't afford you guys anymore.

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