71 replies to this topic

[Phil Smith]

I have been wondering this of late - How did we get to the point where higher voltages like 14.1 or higher voltage is being run on slot car tracks...

Very interesting post!

[RomanK]

Tony,

Hard to tell from a distance but sounds like a voltage drop situation. Voltage drop is proportional to load so a lighter drawing mill wouldn't cause as much drop as one that draws a heavier current. As the PS tries to run, voltage drops causing the mill to run slower and draw more current, more current equals more heat.

Could be as simple as loose connections or as involved as undersized wiring or possibly not enough taps.

[Ron Hershman]

The track has a ground return/wiring problem.

[tonyp]

Is that easy to fix? Or is it a major rewiring? I am clueless on track wiring..

[Ron Hershman]

Is that easy to fix? Or is it a major rewiring? I am clueless on track wiring..

Shouldn't be... just needs a larger size return wire/cable. Rick will tell you I am sure. Where is Desi when we need a explanation??? LOL

The question was asked :"How did we get to higher track voltages? I answered it. From the Drag Strip.

So how about starting another thread on how to deal with excessive voltage on commercial tracks already

Sorry, Mark... we were racing on 16 plus volts way before the drag racers started in the late '80s.

[tonyp]

In the '60s we drag raced on 36 volts... Good thing USRA was not around then. LOL...

[Ron Hershman]

So how about starting another thread on how to deal with excessive voltage on commercial tracks already

What is excessive??? Anything over 13.2 volts???

[Rick]

Is that easy to fix? Or is it a major rewiring? I am clueless on track wiring..

As Roman says without seeing it, it would be tough to diagnose. First thoughts are the same as Ron, too small a return, it might only have two taps? Some will split the taps, pos/neg, and call it four when in reality it's still just two. This is pretty common problem (too small a return) on most track wiring.

How does just one car run on the track? How much does the track back up when all eight cars are on there running? Most tracks will back up about 2 tenths from running a single car to eight lanes being used.

Although the Puppy Dog is a low amp motor, I will bet you would be amazed at the actual amp draw it calls for on the track. Hook up an amp meter between the controller and the post someday.

[tonyp]

Runs the same one or more cars. The Puppy Dogs go down the straights in a death rattle. they never wind up. A F7 kicks there *** all the way around the track. Punch, top end...

Gear them with an 8t to rev them up and they smoke...

[Rick]

Ewwwwwwwwww... sounds bad. LOL. For sure wiring and probably both sides in this instance.

[Rick]

Mark to answer the question at hand, how did we get to high voltages, that's a pretty easy one really.

In the late 80's, slot cars began a resurgence and wing racing was king. All the track were trying to get fast times at their raceways to get the racers in the shop. It was an evil circle. If R-Geo went 2.3, then Chicago and New York wanted to 2.1 etc. Voltage and batteries were getting built up, chargers were left on for racing and qualifying, all for the fastest lap times. Euro Kings were just beginning to come into vogue and tracks were built with more banking to go faster, and hold more volts. Really destroyed open motors. LOL. I think Tri-state USRA was the first to install a voltage limit in their series. Then the mishap in Chitown, Ron spoke of. Although the arm would have probably come apart on 14 also, just drilled too deep.

So it escalated to just wanting to go faster and faster. Wing cars were the dominant cars at the time. When the USRA adopted voltage limits that ended the voltage wars and the tracks were just made faster to keep the times dropping until you have 2010.................

[Rick]

Well, my answer pre-dates the 80's. The concept of voltages being introduced above 12 v goes back to drag racing as was pointed out by Tony P. So, while there may be a newer version, it all really started with getting padlocks to go faster.

I think Marty more meant about general slot tracks, not drag strips in his initial question?

[tonyp]

We used 36d's on the drags in the open class where we raced. They were faster than the padlocks. They ran fine. They were all epoxied and balanced... Big gauge for then, 26 and 27 doubles...

[Ron Hershman]

Mark to answer the question at hand, how did we get to high voltages, that's a pretty easy one really.

In the late 80's, slot cars began a resurgence and wing racing was king. All the track were trying to get fast times at their raceways to get the racers in the shop. It was an evil circle. If R-Geo went 2.3, then Chicago and New York wanted to 2.1 etc. Voltage and batteries were getting built up, chargers were left on for racing and qualifying, all for the fastest lap times. Euro Kings were just beginning to come into vogue and tracks were built with more banking to go faster, and hold more volts. Really destroyed open motors. LOL. I think Tri-state USRA was the first to install a voltage limit in their series. Then the mishap in Chitown, Ron spoke of. Although the arm would have probably come apart on 14 also, just drilled too deep.

Yea and while the track styles were changing..... don't forget "long" timers/tracks that were racing for 5 and half minute heats on the slower tracks while the faster tracks were racing 5 minute heats.

Then there was a few "fast" timers being used for qualifying.

Then there was one track in Michigan were they had switches up in the race directors booth where they could switch any lane from 13-14 volts to 18 volts depending on who was on what lane.... make your buddy go faster or make your enemy burn up.

[Rick]

SCM refers to one sector of slot racers and that is Wing Car Racers, period!

[tonyp]

This was late 66 early 67. All pretty crude, but fun. They did not have any starting lights where we ran, they just threw the common switch. No reaction times, just the fastest car..

[Ramcatlarry]

When I first started to read this thread, I thought it might be homeset oriented. The issue there is that to have 12 volts DC under two or more car loads, those wimpy wall wart power supplies have to be rated at 14 volts without load.

I have long promoted the basic goal of model slotcars to be raced on automotive battery (12 VDC) as a standard. The reality is that the meter shows our "standard" 12 VDC to be a little higher at 13.2-13.4 VDC. I have no problem with that either. What I HAVE seen problems with is 1)the need for speed. 2)power source standards. 3)changing technology.
The need for speed is a human trait that CAN be habit forming - and we have addition treatment centers for that. Changing technology is an area that I have witnessed over the years. Many of the vintage tracks of the 1960's used voltage stepping power supplies, but had limited wattage and a poor understanding of the needs of our form of racing.
When I had the opportunity to dicsect the Vintage 140 track that I bought in the 1990's, I found one 18 gauge power tap and two 4 amp power supplies - one for each of the four lanes. I rewired that track with three taps of 12 gauge wire and an 8D battery. I remember power surges galore on that track in the 1960's - and we only had one motor rule: RUN WHAT YOU BRUNG. In the 1980s and early 1990's we raced with the big automotive (and some trickle type) battery chargers on the car and truck batteries. Rarely did a race end without at least one fried motor and plume of smoke. The raceway owners also could not keep fluids in the batteries without weekly fill-ups and annual battery replacements.
Battery chargers have largely been replaced (or SHOULD BE) by now with the RV industry AC/DC power converters of the IOTA/Bulldog variety that give a much cleaner power and stable charging rate for lead acid batteries. Many local building codes and inspectors have banned the use of liquid batteries in stores due to the charger issues of Hydrogen out-gassing that are eliminated by the use of these RV chargers - and we CAN control the output voltage under 14 VDC. Many raceways have gone sans battery, but not low amperage by using the even newer technology of the Server power supply where 300 amp/ 5 VDC units are wired in series to provide an adjustable DC voltage.
I have also used one to three Farad Capacitors on tracks from the car audio industry and feel that they reduce motor damage issues from the power supplies that have limited built-in capacitance.

[idare2bdul]

Ban chokes and motor changes and the rest will tend to work itself out. The Speed Crazed Morons alway push past reason if they can. Then they are reluctant to call it a mistake because by then they have developed the technology to cope with their insanity and want to preserve their investments and not lose their technological edge.

[Ramcatlarry]

Another standard track detail that I have developed and promote is the use of a fourth post on the driver panel.

The GRAY post is a three volt choke formed by making a four diode series chain from the white post. I use the basic three amp diodes which also make a current limiter and works well for all 30 gauge armatures or smaller for rentals and little kids just learning to make laps. Just hook up a standard controller with the white clip on the gray and let them drive. If they keep the car on the track, they can move up to the white post. It is A whole lot cheaper than having a special set of rental controllers...and more consistent than a lane by lane power controller.

[Ramcatlarry]

I drag raced in the 36 VOLT era. One battery for stock; two batteries for modified; THREE (36 VDC+) for TOP FUEL.
Motors blowed up REAL GOOD!

[Ron Hershman]

It's funny....... as the voltage came up and the AC ripple Power Supplies came into "vogue" the MFG's adapted and made their products better to handle the extra juice... I am talking about 14.5 volts here. I spent countless hours at Parma testing and figuring out how to get the Asian stuff to live through that better, Mura did it, P-S did it, Koford did it, etc etc.

Now here we are again with another Asian motor that can't handle the voltage and now some scream for voltage changes.

Once we can get "uniform" voltage rules or whatever you want to call them and all the raceways follow them, then it could be better, but good luck with getting that to happen.

[tonyp]

In calif they were running power supplies on some tracks long after the east coast was running batteries. LA was never know for having any power on the tracks when the pro racing started in the 60's.

[chaparrAL]

Back around 1979-81 both Momence and Centerville was where the speed crazed morons really upped the game. Multiple semi truck batteries and big chargers are what I remember. Every pro wanted to be the first to do a sub 3 second time. Then in the mid 80's when Grand raceway opened 2.9 was a G 27 time.

[DaveM]

Maybe they didn't do it in the 70's, but they sure as hell started it on the road course King tracks in the mid 80's when all of you were absent and this was before slot drag racing got started up again.

I was there.

i got your back on that one Ron.................

[MSwiss]

Yea and while the track styles were changing..... don't forget "long" timers/tracks that were racing for 5 and half minute heats on the slower tracks while the faster tracks were racing 5 minute heats.

Then there was a few "fast" timers being used for qualifying.

Then there was one track in Michigan were they had switches up in the race directors booth where they could switch any lane from 13-14 volts to 18 volts depending on who was on what lane.... make your buddy go faster or make your enemy burn up.

Ron,
Your history of slots is impeccable.

I remember one of the long timer guys. When you would approach him and ask why he was timing his 3 minute
heats 20 seconds long, his answer was because he checked his dark room timer and found out it was 2 seconds fast every 3 minutes so he set his timer long to compensate.
When I said "OK, then set your timer 2 seconds long, not 20", he looked at me
like I was speaking Martian.

I remember the variable power deal in Michigan. I didn't think he could vary it from lane to lane.
I was later told I was an intended target. Despite an all-star field, I don't think Watson, Pfeiffer or Laster made the main because of the goofy conditions.
I spent a whole lot of time spinning my choke dial but I'm pretty sure I won by at least 70 laps over
some handsome young racer running for Parma.