3573 replies to this topic

[havlicek]

I'm thinking that the smaller airgap and full can will make this one more of a monster motor than the 'strapnut'!

Hi Don,

I think they will have different characteristics...the Strapnut may have the edge on RPMs...being able to spin a little more freely, and the full can may have a bit more torque. It will be interesting to see what difference the two setups make as everything else is about equal. I say "about" since no two arms are exactly the same, but I think they should be close enough so that the setups will be the main difference.

And then I think about the 23/25 motor you are going to do next.....WOW!!

I have the setup pretty much done and have already wound an arm, but it still had a little vibration after balancing it... so I'm on arm #2. I'd like to send out only the best I can do and figure a second arm is a small amount of extra effort to go through. Both "25's" measure pretty far down resistance-wise...somewhere between .1 and .2 ohm so the little bit of extra wire on there doesn't seem to be hurting things much Stay tuned for "pictures at eleven on your local Slotblog Network News"!

-john

[havlicek]

I finished motor #3 or 3 for Don Weaver. This one got the same PS can, new Hawk endbell, Emovendo neos shimmed, ball bearings on both ends, shunts etc. Difference here was I wound him a 23T #25awg arm. The arm blank is a new Mura .007" lam assembly with a Bill Bugenis com. The motor sounds pretty scarey at 5.5V, so at full power it should be impressive. I don't know what voltage they run drag cars at, but I hope it's not too far above 12V Use the force wisely Don



-john

[Don Weaver]

John,

Boy, these should keep me busy for quite awhile! I've ordered the new JDS Neo chassis for the 23/25 motor and hopefully it will be at 'Slots of Fun' when I go over there this weekend. Drag cars are run at 16.2 volts so listen carefully Saturday week and you might just hear it ! I'm hoping once I learn how to prepare the track I'll see something in the 4's on the 1/8th mile track at 'SoF'. Thanks so much for your efforts in building these three motors for me.....they are just way cool!

Don Weaver

[GearBear]

Don,

With that monster power will you be using a special Drag controller? Or a push button? Or a 1 ohm Parma? I would think you will want to stay away from the push button as you will need to soften the power to the motor just a bit. Looks like fun!

[Don Weaver]

I also want to thank Marty N. (a new member here on Slotblog) for his help on what airgaps and timing to run on these Neo motors. If you like drag cars, check out his website at 'Kahale & Martin'.....his meticulous process for building high end drag cars makes for interesting reading and good ideas.

Don Weaver

[Don Weaver]

Gary,

For now I'm going to use my 30 Band Difalco but I will probably look for a more drag specific controller in the future if I can learn how set up and stage these types of cars. Isn't Havlicek's work AWESOME?

Don Weaver

[havlicek]

Drag cars are run at 16.2 volts so listen carefully Saturday week and you might just hear it !

Aw crud...I hope you guys run those things from behind a blast shield! Dang, if the motor sounds scarey at 5.5V./..it WILL BE SCAREY at 16.2 volts. I had no idea they were run that high and hope the thing (even for those short bursts) holds together. I figure this motor would be a stormer at 12V, and even a 23/25 with a bit of extra wire (I usually figure #25 winds to go from 19-22 turns) might become some sort of WMD. This will be interesting

-john

[Don Weaver]

The main thing will be keeping the tires from melting! Like I said I'm hoping that this thing will run somewhere in the 4 tenths of a second range once I figure out how to set the track up, maybe faster if the 75 amp power supply allows. Maybe I need to use a choke to start with !

Don Weaver

['Slots of Fun']

The motor will probably have great brakes...but that's not so important in a drag car...
-john

Oh yes it is! With Don running these motors @ 17 volts on a 1/8 scale drag strip, I'll have to extend the shutdown area from Abbeville to Chicago! If I keep the shutdown area the same length it is now, Abbeville will have its first Particle Accelerator!

Very nice builds John.
V/R,
Don

[Don Weaver]

Get out the sledgehammer, Don....let's knock a hole in that wall !!

Don Weaver

[Marty N]

Aw crud...I hope you guys run those things from behind a blast shield! Dang, if the motor sounds scarey at 5.5V./..it WILL BE SCAREY at 16.2 volts. I had no idea they were run that high and hope the thing (even for those short bursts) holds together. I figure this motor would be a stormer at 12V, and even a 23/25 with a bit of extra wire (I usually figure #25 winds to go from 19-22 turns) might become some sort of WMD. This will be interesting

-john

John, blown arms is part of Neo/FC drag racing I haven't blown one yet so I'm nut pushing hard enough yet

We've got our quickest passes at Mid-America where we have access to 16.4 volts, over 325 amps, 1 Fd caps and 2/0 wire on a new Gerding 1/4. I believe the current track records are .426 ET and 141 MPH. Rodger Chiechi holding both ends of that. At 55 grams I've been with a 25/25 wind .499 and over 113 mph. Going back in a few weeks with another 145 watts

[wbugenis]

Hi Martin,

John and I were discussing whether this one would hold up. I told him if I knew he were building a 16 Volt motor I would have sent a '"select" commutator. We usually cap the coms for eurosport arms.
Be interesting to see what happens.

Bill

[havlicek]

Yes, this one will be interesting Bill...especially since there's no room to cap the coms on these things. I now understand the 25/25 thing also, and will have to see what the patterns look like to get that on an arm. I may also do a little cutting/hacking/slicing& dicing to build a test-bed motor for this stuff when I get a chance since it's something I know less-than-zero about. I have an extra set of the Emovendo neos here and lots of cans and endbells to screw around with.

-john

[havlicek]

Oh yes it is! With Don running these motors @ 17 volts on a 1/8 scale drag strip, I'll have to extend the shutdown area from Abbeville to Chicago! If I keep the shutdown area the same length it is now, Abbeville will have its first Particle Accelerator!

Very nice builds John.
V/R,
Don

OK then just the static pull of the neos on these motors should help with that ...but now we're talking about 17V!!!???

-john

[Don Weaver]

John,

It's just a little over 16 volts @ 75 amps at 'Slots of Fun'. I thought about asking about capped comms but figured they wouldn't be available seperately so I didn't persue it.....my bad. On the positive side, drag racers use 'standard' arms all the time on 16+ volts and they hold up pretty well. In fact, I've been running a stock Hawk 7 and haven't had any problems with it and everybody knows how these types of motors hate over voltage.

Oh well, we shall soon see !

Don Weaver

[havlicek]

Hi Don,

Maybe I'm just being a worry wart over here and everything will be OK. In the future however, I will do things a little differently just in case. I also threw together a test bed motor for this stuff now that I have a little better idea of what we're dealing with. I used one of the endbells you sent (Koford?) after speaking some more with Marty since he said that ultra light would help things. It's significantly lighter than say a Mura and probably even the Hawk and the hardware is awfully nice too. I'm not even sure I assembled it correctly since there were these tissue-paper-thin brush plates for under the hoods . I replaced the supplied spring posts with PS ones that would allow for more choices with springs. There was precious little material after fitting (actually even before fitting), so I had to drill it top and bottom for endbell retaining screws. There's some more work to do with it, but at least it proves the concept. I can remove can material to lighten it further, but for now this should work. This setup should allow for at least a .350" stack...maybe a bit longer, and I can always cut the can longer and get up to a .400" stack or longer. With the Emovendo neos being so short, I'm not at all sure that a longer stack would be necessary.



-john

[Marty N]

Hi Martin,

John and I were discussing whether this one would hold up. I told him if I knew he were building a 16 Volt motor I would have sent a '"select" commutator. We usually cap the coms for eurosport arms.
Be interesting to see what happens.

Bill

As John pointed out Bill there just isn't any room for a comm cap. On the plus side the Neo motors don't tend to pull the rpm a cobalt does. Low turn, big wire Neo's, 140 to 170K versus 200K+ with cobalts?? Don's wind will fall in the 130 to 135K range.

[Don Weaver]

Welcome to Slotblog, Marty! Any suggestions on gearing for the G27's and the 23/25? Going to use the new JDS Neo chassis to start with the full can G27, lexan body and .500 or .435 X 1.06 tires. Power is 16.2 volts @75 amps (no battery) on 1/8th mile track. Thanks again for all your help on specing out the motors.

Don Weaver

[Marty N]

Welcome to Slotblog, Marty! Any suggestions on gearing for the G27's and the 23/25? Going to use the new JDS Neo chassis to start with the full can G27, lexan body and .500 or .435 X 1.06 tires. Power is 16.2 volts @75 amps (no battery) on 1/8th mile track. Thanks again for all your help on specing out the motors.

Don Weaver

On that tire, wieght and distance? The .435 will be quicker, the .500 easier to glue up..you choose. Hum....13/54 for both motors. With only a 75 amps supply it will be a bit sluggish. The 27 may actually out run the 23 with such low power to draw from. Could try a 12 pinion if it just doesn't want to get out of the gate. I'm am guessing here as I haven't run on a track with such a current limit. What I do know is that the 23 turn motor will be asking for something north of 60 amps in the trap.

[wbugenis]

As John pointed out Bill there just isn't any room for a comm cap. On the plus side the Neo motors don't tend to pull the rpm a cobalt does. Low turn, big wire Neo's, 140 to 170K versus 200K+ with cobalts?? Don's wind will fall in the 130 to 135K range.

I'm thinking eurosport rpm. Forgot drag motoes are toeque motors. I'm thinking it might be ok.

Bill

['Slots of Fun']

On that tire, wieght and distance? The .435 will be quicker, the .500 easier to glue up..you choose. Hum....13/54 for both motors. With only a 75 amps supply it will be a bit sluggish. The 27 may actually out run the 23 with such low power to draw from. Could try a 12 pinion if it just doesn't want to get out of the gate. I'm am guessing here as I haven't run on a track with such a current limit. What I do know is that the 23 turn motor will be asking for something north of 60 amps in the trap.

Marty,

Don was mistaken. We have a Bulldog 90 amp power supply.

V/R,
Don

[Marty N]

Marty,

Don was mistaken. We have a Bulldog 90 amp power supply.

V/R,
Don

That's good news of him. Thanks for the info. Won't change the gear though just give the 23 a quicker spool.

[havlicek]

With a little more knowledge about these drag motors (a dangerous thing), I set about to winding an arm for the setup I'm building. The stack was assembled from some .014" lams of unknown origin with a thicker leg. On this one, in addition to the usual breaking of all the sharp edges at the stack ends with a tiny diamond point, I coated the stack with the same HT epoxy ("Duralco 4461") as I use for coating the coils. It's much tougher than the furnace cement and more closely approximates the coatings on commercial arms...although it's a relative pain in the keister to do it this way. Once again, it got a Bugenis com and I'm much more comfortable welding these things now (with some very helpful thoughts about that from Bill). The wind is 25T/#25awg and that's the wind that Don Weaver had asked about originally. Because the crown is somewhat thinner on these lams, I was able to work out a nice tight pattern to get that much big wire on there with no problems. I'm always throwing out wire when I have to figure this stuff out, but I have a few different types of winds I can go through now (after a lot of sore fingers) to see how to approach these things. That's one of the things about lots and lots of practice that comes up. If you get stuck winding one way (there are a bunch of ways to do this), you may never find a good method for a getting a given wind on a particular blank. It can pay to think outside the box here. Anyway, here's what I got:


This one I'm going to send to Bill for dynamic balancing and we'll see what's what when it gets back. It was spaced and setup for the test "drag" setup and is a nice fit. It's got way more wire on it than I would have considered putting on there normally...but ???

-john

[HarV Wallbanger III]

"Their building bombs" That's what the hotel maids told the manager at the Nats in Houston in '85, after seeing all the equipment in the rooms. "They" ....the GP7 racers had so much stuff in the rooms pulling amps they blew out one whole floor! So watch out John one of your neighbors may call on you for the same thing!
Beautiful work John! (wear eye protection!

[havlicek]

Hi Barney and thanks I sometimes get funny looks from the Post Office when I mail this stuff out. They ask the usual "anything fragile, liquid, perishable, hazardous, explosive, smelly, disgusting, flammable, sensitive, stupid, etc." stuff and I say ..."nope"...and the they will still often ask: "well...what IS in there?". When I tell them "toy motors", I sometimes get a look like "aren't you a little old for that"? ...next up a lovely old Mabuchi FT36D Champion with Arcos. Talk about a change of pace!

-john