30 replies to this topic

[mark1]

When I saw a hawk motor for the first time, I didn't like it. Doesn't even look like a slot car motor. BUT, after seeing these things produce a lot of fun, close, chaep racing, I'm tolerating them more.

 

I've learned a few things along the way. So how about some tips and tricks to pass along to fellow racers?

 

I have noticed that the connectors for the lead wires can move in and out when you pull on them. That probably isn't good. I use a couple of drops of krazy glue to firm that up.

 

Also, I look at these things with a cheap otoscope. Even very careful soldering of the lead wires will distort the plastic around the brush springs. So I solder the wires on before break-in. Might start using clips for the lead wires.

 

Anybody else have anything to share. Help fellow racers if you can!

[Bill from NH]

If you want to keep all heat out of them, use the leadwire clips & glue, rather than solder, pinions to the arm shaft. 

[MSwiss]

You forgot "and never run them".

 

Soldering the pinion on can't possibly get the motor hotter than it will get when racing.

 

If it did get that hot, you couldn't hold the motor, on your work area, with your bare fingers.

[Pablo]

I don't understand why it "doesn't look like a slot car motor" to you? This is a JK Hawk

 

 

 

 

[Bill from NH]

 

Soldering the pinion on can't possibly get the motor hotter than it will get when racing.

 

If it did get that hot, you couldn't hold the motor, on your work area, with your bare fingers.

 

You need too preach to the 1/32 guys, they're the ones who glue on pinions.    I've always put my own on with fine hi-temp silver solder I got from Russ Boyington in the 1970s.

[Eddie Fleming]

Bill there are more people using glue (if you want to call it that) on pinions than you may think.

[MSwiss]

I don't understand why it "doesn't look like a slot car motor" to you? This is a JK Hawk
 
JK3030__74736.1493713716.jpg

There are Hawk 7's, 9's, 11's and Retro's.

I think everyone here knew which style he was referring to.

You need too preach to the 1/32 guys, they're the ones who glue on pinions.    I've always put my own on with fine hi-temp silver solder I got from Russ Boyington in the 1970s.

I think that might be because a lot of those guys aren't real proficient with soldering as there is very little of it on those cars.

I get a kick out of how the guys who race the annual 24 hour enduro, in Michigan, have to decide whether to glue their motor in to improve gear reliability, or leave it unglued to make changing motors easier.

[Pablo]

There are Hawk 7's, 9's, 11's and Retro's.

I think everyone here knew which style he was referring to.

 

 

I personally was sure he was referring to FK style Hawks. But I wish people would be specific about exactly which motor they are referring to for the sake of those who may not know    

[team burrito]

both motors are great - it depends on what you're racing. on race nights, whichever car works the better is the one i use. lately, i've using the jk hawk 9 with great results - it's really drivable & quite fast. for the rebuildable motors, i like the jk hawk 6 with ball bearings, copper brush hoods & a big dog armature - great horsepower & it's very drivable as well.

[mark1]

You are right, Pablo. I forgot about the Hawk 6! We use the hawk 7 in 4 1/2" stock  cars. Brazilian flag motor in womps. I guess they are fk130. It is, for me anyway, like calling certain pliers Channellock even when they might be Snap On or Craftsman. Like Bill said, I gave some thought to keeping heat out of the motor. I've used low temp solder on them. Like many things, no proof that it helped, but it didn't hurt. Anyway, if you guys have any tips, tricks, observations, post 'em up!

[Pablo]

On the FK-type motors, you are right in not wanting to apply lots of heat to the tabs. I pre-tin my wire attachment tabs using 60/40 and acid on both sides. Load the tip with enough solder so it flows instantly with just a touch. Practice on a junk motor. The tabs must be clean. Tin any solder attachment points on the can and pinion shaft area same way. Solder on pinion.

 

Now wash the motor in Dawn and baking soda, rinse and air dry completely. At this point you are done introducing acid. Pre-tin your wires with paste flux (Aeroflow). Re-apply flux to wires and both sides of the tabs. Load "a little" 60/40 and all it should take is an instant touch of the tip to make the wires melt into the tabs.

 

Clean the tabs with a Q-tip and iso alc. Or lighter fluid. Can attachment points you tinned can now easily be soldered to chassis with the paste flux only.

 

This has pretty much been covered in my subforum on every car I've installed an FK type motor in. Here is a good one, using a Hawk 7:

 

http://slotblog.net/...r-step-by-step/

[Pablo]

Also, on the FK-type motors you want to make sure your lead wires are not pushing and pulling those tabs when the flag rotates in corners. Could result in tweaking the brushes, causing variable performance, arcing, and premature brush wear. Especially important if you are using stiff wires.

 

Use of earring keepers (clutch earring hinges) is one way to help with this. It just depends on the build.

[mark1]

Thanks Pablo! Lots of great info there! Anybody else have any tips?

[Pablo]

The ones that come with extra shaft length on the EB side - do not trim that off - it acts as a heat sink

[mark1]

Ok, cool! thanks again, Pablo! I might try one of those little heat sinks that you press on to the shaft. Also, for those who use screws to mount the motor, take care not to distort the can. It could bind up the arm. I use a heat sink on the tabs for lead wires

[Pablo]

"those little heat sinks that you press on to the shaft" are called "comm coolers". Trinity sells these:

 

 

and these

 

 

"take care not to distort the can. It could bind up the arm" FK cans are pretty stout but that's good advice. On every motor I always check the amp draw before installation, then re-check after installation. That way you know if something got tweaked. Just a means of verifying nothing changed.

 

"I use a heat sink on the tabs for lead wires"  I do not recommend that. Anything you attach to the tabs is going to require more power to get the job done. Again, if this process takes more that 1/2 of a second, you are doing something wrong.

 

 

 

 

 

[mark1]

Pablo, I didn't notice any difference when soldering the wires when the heatsink was attached. I see your point, though!  Race tonight. Downriver Speedway. Stockcars on the oval, Womps on the Grandstand. Both cars use Hawk style motors. A few of our racers are in Chicago, racing flexis. Good luck to them!  Thanks for all the go fast tips! I'll share them with the other racers.

[Bill from NH]

. I use a heat sink on the tabs for lead wires

Mark ,do you mean you solder connectors to your leadwire, then push those connectors onto the motor tabs without adding anything to the motor tabs themselves? Those connectors can be purchased commercially or you can make your own using brass or copper tubing.

[MSwiss]

Here are the ones I sell.

They are a pretty good seller, but I'm sure a lot more people solder direct to the tabs, especially with anglewinders, where the connector isn't very practical, because of it's length.

[mark1]

I have been soldering lead wires to the tabs on the motor. I'm going to try some of those lead wire clips.

[Horsepower]

So what happened to the press on pinion? I usually only work on vintage motors so any pinion I press on fits tight. Tight enough that I have to use a gear puller to get it off. What's the reason for soldering on the new motors? Just wondering.

[Bill from NH]

Gary, my experience with press-on pinions is they can only be pressed on just so many times before the shaft hole becomes enlarged. At that point, you either solder it on or get a new pinion. These were Sonic SS pinions, rather than somebody's brass ones.. In my opinion, a soldered-on pinion has a more positive grip on an arm shaft than a press-on. I've even taken a press-on pinion & reamed out the shaft hole so they could be soldered on more permanently..

[Don Weaver]

It's an easy way to screw up a perfectly good arm.  Shaft material isn't the best on these motors and bent shafts cause all kinds of problems.

[Horsepower]

Thanks Bill! You too, Don!

[Pablo]

The only way you are going to screw up an arm shaft pressing on a pinion is going past the hilt. In other words, pressing it on so far you are squeezing the shaft.

 

But no serious commercial full size track 1/24 racers use press on pinions. Not since about 1968.