# Questions about HO pickup springs



## Dave G. (May 26, 2009)

While checking out the various online sources for parts, I've noticed that there is a wide variety of pickup springs available. There are light springs, medium springs, heavy springs, helper springs etc etc.

My question is: Is there a particular set up that you would use a specific spring for? Is one type of spring better for a tight twisty road course or is one better for a track with long straights? Or does it depend on the type of chassis that you are running (G3, T-Jets, Tyco, magnet, non magnet, etc)?

Or is it a matter of trial and error and finding something that works well for you?


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## blubyu (May 4, 2008)

Always a matter of trial and error to find the best balance of speed and handling. As far as light to heavy springs you are going to use the heavy ones with the stronger magnets like NEO and polymer,the lighter to medium on CERAMIC and lower strength polymer magnet cars. Helper springs are to get even more fine tuning.Now on a banked oval you might get away with heavy springs on the lower downforce magnets.


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## FLASH (Nov 7, 2006)

Like the previous post it is trial and error but a simple rule of thumb is lighter tension = less speed, better handling. Heavier tension = more speed, less handling.


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## Bill Hall (Jan 6, 2007)

Dave ....just my humble "O"...

I'd give more consideration to the adjustment of your pick-up shoe's contact patches as they relate to a given chassis setup. ESPECIALLY if you have altered tire profiles and wheel diameters. Parallelism between the rail and patch has EVERYTHING to do with good current transfer.

A setup with a good linear contact patch can use less spring pressure and transfer current more efficiently than a setup with a poor contact patch with the springs gunned down ridiculously tight in order to compensate for bad geometry. Less drag/resistance = more speed, improved shoe life, better handling in the turns, as well as better handling via a smoother acceleration deceleration response.

As previously stated, it requires some tinkering to get the balance right. Once you've got the shoes tracking properly; sneak up on the springs incremmentally from the lighter side. Eventually you reach the break point where the handling becomes disagreeable or the chassis gets slower and klunky feeling... then back up a notch or two.

Try to keep in mind that all recommended settings are just that...to get you in the ball park. Your results may vary, so it's up to you to find the sweet spot!

Good luck!


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## Rolls (Jan 1, 2010)

When thinking about springs and pickups, especially on pancake chassis, I've found Bill's short video and SwamperGene's pictures to be very helpful. :thumbsup:

These links really should be included in the AW packaging.


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## Sir Slotsalot (Jan 23, 2010)

Help!

I run SRT's with heavy downforce traction magnets on Tomy track. I've relied on stock p/u shoe springs with variations on front wheel "profile" to find the "sweet spot" for best contact and least amount of shoe wear. The cars are fast and do handle very well but shoe wear is still an issue. I don't mind the expense of replacing shoes after about 50 or so laps, it's just the idea of having to do it so frequently. The variations in rail height on Tomy track does not make the job any easier. I doubt there is any "one" solution either, but I'm all ears for suggestions.


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## Bill Hall (Jan 6, 2007)

*Chiseling*

Agreed, shoe wear is probably one of the most annoying things about high zoop cars. I'm usually wrong a couple times a week, even when I keep my mouth shut. IMHO sectional track only aggrevates the condition. 

Assuming that your spring pressure isnt set on grinder mode and your contact patch shows a pretty even burn across it's length; I'd look at the sectional joints. By looking, I mean lay a small straight edge or the like on the rail and slide it up to the joint in the direction of travel. Anywhere it stops is a scale router-jointer. Think of that edge as a chisel and the car is the hammer. Obviously the fix would be continuous rail to negate the sectional joints and their damaging steps. Right? 

So when you run around the track your roto-hammering your shoes. Naturally the shoe loses. Shoes can get bit either on the leading or trailing edge depending on their inclination. In other words stepping off the joint with the contact patch "heeled" takes a bite off the back of the shoe; although not nearly as hard as the blunt force trauma of the "toed" contact patch coming forward onto a rail step. These are the same snaggles that that will shred nice new braids into rags too. The clickety clacks of old have changed their tune as the chassis technology has improved over the years. It's a lower tone now... more of a thwackety thwack which IMHO is a function of magnetic attraction making the "hit" more direct and unforgiving rather than a glancing blow like pre-mag cars which tend to bounce up a bit and dissapate the blow. All this at a much faster rate between the notes due to the warp speed of todays cars. With anti-gravity cars the shoe is between the rock and the hard place. Instead of knicking the shoes on bad rail joints bit by bit; we now gouge them out lineally because the car's natural response to ride or pop up is over powered by the traction magnets. 

Another good place to look, if you use them, is slip on tires. That delicious gravy we clean off our tires tells a story too. Under magnification, the goobery residue on your tires contains all sorts of crap. The indicator of shoe chiseling is shards, chips, and curls imbedded on the surface of your tires. Not to be confused with the normal fine paste like residue akin to what you would see build up on an old t-jet gear plate.

Of course one could massage each joint; which can require periodic follow ups due to variations in your plastic road bed or mounting substrate brought about by changes in humidity or temperature. In much the same way as a model rail roader will perfect each rail joint or transition, I chose to massage my joints and maintain the occassional "poppy upper" because I can. It makes a big difference when running on sectional track.

Ultimately, it's helpful to keep in mind that shoes, like carbon brushes, springs, tires, bearings, commutators, gears, journals OR any other MOVING part should be classified as a "normal wear item". The trick is to keep the intervals in the ball park.

I'm a firm believer in the idea that there's always lost knowledge everytime we take a huge leap forward. Modern rocket cars WITH the same old tired TOY track. If you have any, take a close look at the old school t-jet pick up shoes. They have a huge roll at beginning and end of the contact patches and a good bit of travel in the system. I believe they were put there for a reason. I think the original engineers knew that the shoes were going to need a little help compensating for the draw backs of sectional track. Obviously they were capable of making tight angular bends but they chose to make it a gentle curve. For that reason I always include a little toe roll into every shoe adjustment, just because I run on sectional track.


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## Sir Slotsalot (Jan 23, 2010)

Thanks Bill,

The majority of my rail joints are soldered but like you said, they could be "tweaked" a little maybe with a fine stone on a Dremel and a steady hand. Unfortunately, that's been on my list of "things I hate to do". When you finally get a few minutes peace in the slot-cave, the first thing you want to do is well...Race!! It's like trying to avoid chocolate chip cookies. I'll have to hide the cars better and pretend I don't have any. Then perhaps I'll get to that list. Hey, you think the wife would "buy" the excuse "Honey, I could not find my old cars so I had to buy new ones"? Try anything once...


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## Bill Hall (Jan 6, 2007)

Oh jeez yeah...I had to force myself to fix them. What worked for me was to finish a couple every time I had a moment until I got around. 

I prefer a sharp flat file so that the approaches "material on either side" to the joint is removed somewhat evenly across the entire transition. Ya dont want to risk digging a pot hole into the rail. It helps to use a snug fitting pair of the canvas work gloves with the blue rubber gripping surfaces. They really help with the assosciated hand fatigue. 

The file also tells you when you reach "DUN" as it will slide across the joint nicely in both directions. Then a few passes with a fine stone, then wrap the stone in 600 to polish them off.


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## blubyu (May 4, 2008)

I would fix the joints soon. 50 laps and wearing shoes out is wayyyyyyyy to soon,I did 931 laps at are last race with new shoes and there still in race shape. This is on a high banked tri-oval.


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## Rolls (Jan 1, 2010)

Or at least inspect them all, because one or two real bad ones will wreak havoc, and the mag cars won't complain as loud or hop up and down about it like the non-mags.


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## Sir Slotsalot (Jan 23, 2010)

I agree. The track is 13.6 overall length with 4 major straights and 6 curves including a hi-bank turn. It takes anywhere from 50-100 laps(depending on the car)for the shoes to show a "groove". Any more laps and the grooves turn into holes. It's primarily the SRT's because of hi-downforce traction mags. I have BSRT G3's (901) that do not wear as quickly but they are pretty much "boxstock".

Does anybody make a highly conductive "paste" that one could apply a small amount over the joint as a "filler", trowel the excess and grind to a smooth finish? Perhaps I'm dreaming.


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## LeeRoy98 (Jul 8, 2005)

Sir Slotsalot said:


> I agree. The track is 13.6 overall length with 4 major straights and 6 curves including a hi-bank turn. It takes anywhere from 50-100 laps(depending on the car)for the shoes to show a "groove". Any more laps and the grooves turn into holes. It's primarily the SRT's because of hi-downforce traction mags. I have BSRT G3's (901) that do not wear as quickly but they are pretty much "boxstock".
> 
> Does anybody make a highly conductive "paste" that one could apply a small amount over the joint as a "filler", trowel the excess and grind to a smooth finish? Perhaps I'm dreaming.


I don't run on a hi-bank sectional, but I'm curious if the combination of the traction magnets, shoe setup, and the arc in the banking adding extra stress to the shoes?

Just a thought...

Gary
AKA LeeRoy98
www.marioncountyraceway.com


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## Sir Slotsalot (Jan 23, 2010)

Good point Gary. Tomy's banked section has a pretty stiff arc. It's almost unrealistic but fun. I've had to grind a little off the rear body "low spots" to eliminate scraping on the pavement. Once you do that, the cars do really fly through that section especially when you "nail it" coming out of the chute onto the back stretch. A lot of centrifugal "down force" going on. It's a fast track and I "pound" the cars pretty hard. More p/u shoes, a small price to pay for speed and handling.


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