The BSA nail

Secrets, tips, tools, design considerations, materials, the "science" behind it all, and other topics related to building the cars and semi-trucks.
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Speedster
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The BSA nail

Post by Speedster »

What is it we are asking the nail to do? What is done to that nail by racers in an effort to achieve their goal?

I'll call it the Extremes.

1. Sanding with 6 grades of sandpaper, removing all casting marks, polishing with Brasso,, soaking in 91% alcohol for 15 minutes, covering with Lemon Pledge, buffing the Lemon Pledge, adding graphite, put in a sandwich bag with a moisture remover.

2. Remove casting marks under the head of the nail.

Whatever is done to the nail is either going to make it better or worse toward the goal. It will never be the same as it was when it came out of the box.

What have you done to the nail?
Did it make it better toward your goal?

PROVE IT.

A Reminder. The nail doesn't turn.
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Re: The BSA nail

Post by Kenny »

This was my Sons final axle prep process as a Webelos II Scout, much of it improved and adapted over time using methods from me (Dad), who raced in an adults-only class. I will only post the things our Pack and District rules allowed (or didn't explicitly forbid) for competing Scouts. Your Pack and District rules may be different, and you'll need to adapt for them. We were permitted to race 3-wheels down. We raced on 48ft Aluminum tracks.

Important Caveats
Some of these tasks are quite advanced. Young scouts cannot safely perform many of the steps as Tigers. But, as they get older, they can do a lot -if they are willing to work - if you take the time to help them. SOAPBOX: If you build your kid's car, they know it, all the kids will know it, and it's just not the same. Let them do it with your guidance. I might add that it's an incredible teaching opportunity and priceless time with your kid. OK, end of soapbox.

Not all people have access to lathes and drill presses, dial indicators and micrometers, but if you start networking, you'll find someone who does, and they'll almost always be willing to help you. Nearly all tasks can be performed on a regular bench using standard power or hand tools. Achieving the finest tolerances require some real ingenuity, but can be accomplished inexpensively.

Some steps, like polishing axles, can be done safely by some young boys while others may need your help. You'll have to be the judge. In our case, we had an open class for adults and Boy Scouts, which was separate and distinct from the boys' age-based racing classes.

Initial Smoothing
First came precision grinding down the casting using a Dremel tool. We want to knock down any junk on the underside of the nail head and any metal proud of the shaft. A mini-lathe would work superbly for this step, but we never had access to a lathe. After all the bumps and protrusions are ground down, we progressed to spinning the nail and smoothing using it using Emory cloth in a progression of grits 2000, 4000, 6000, 12000.

We always tried to remove as little material as possible using a progression of Micro-Mesh precision abrasives cut into strips to 12,000 grit with nail mounted straight in a drill press or mini-lathe and then checked (runout) for straightness. I cannot stress enough how light the pressure used at these stages. We spun the axle at very low speed to avoid heating it up and also to minimize material removal. Once casting marks are smoothed off and verified visually using a 20x loupe, we gave a slight convex slope to the inside of the nail (axle) head.

We plated the nail with nickel. Plating is relatively easy, and your Scout will learn some more neat stuff. After plating and again verifying smooth visually, and thickness using a micrometer, the axle is ready for polishing.

Polishing
The axle gets polished using Mother's Mag Polish applied at a slow speed using old tee-shirt cotton strips loaded with a small amount of polish cream. Once the cotton strip turns black, a new clean cotton strip is used to buff out the axle, keep buffing with clean strips until it's clean, and you can see yourself in it and no more black on the cotton cloth. The objective is to achieve a smooth mirror polished surface completely so that no matter where the wheel hub contacts the axle it will meet a consistent and smooth surface.

Note that the point of the axle or nail, the part mounted in the drill, is not polished, but we do want to ensure that it's smooth and straight so that it moves without damaging the wood during alignment later.

Bends
Now we should have at least four, preferably more, axles that are straight and polished. They should be tagged and bagged with a measured diameter to later best match up with a known wheel bore diameter. One axle, the "rail runner" steering axle, is precision bent 3 degrees; the three others bent 2 degrees. After verifying the bend, each head is marked with a color-coded reference for alignment later.

Lube
The axles get good cleaning with Everclear. Thoroughly dried, each gets a single drop of Krytox and all excess is removed. After this the car needs to be kept in a clean bag between alignment and testing and race check-in.

Multiple events treatment
After Pack racing, prepared for District by carefully removing all wheels/axles to clean, dry, and reapply lube No more than a week before the event. Keep each axles wheel combo together and replace them in the same hole/slot as before.

Results
My son was undefeated at the Pack level. Taking both his class and Grand Champion. Each year he competed. He won District the first time he competed first out of hundreds of entries. His car failed to finish the following year when his car jumped the end of the track during the first heat, which severely damaged it. That run was the fastest recorded at the event, so who knows?

I hope this helps. It was a nice trip down memory lane.
Speedster
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Re: The BSA nail

Post by Speedster »

Thank you, Kenny.
We cannot plate the nail with nickel but I'm glad you did that. That helps me to explain the point I was trying to make.

The BSA nail comes with a zinc coating. I feel the casting marks under the head should be carefully removed. THE END. Anything done to the nail after that will not make it better for the wheel bore to ride. I cannot prove that. Can anyone prove what they do to a BSA nail improves on the original Zinc coating?
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Re: The BSA nail

Post by Loud2ns »

Speedster wrote:Thank you, Kenny.
We cannot plate the nail with nickel but I'm glad you did that. That helps me to explain the point I was trying to make.

The BSA nail comes with a zinc coating. I feel the casting marks under the head should be carefully removed. THE END. Anything done to the nail after that will not make it better for the wheel bore to ride. I cannot prove that. Can anyone prove what they do to a BSA nail improves on the original Zinc coating?
I have never used a bsa nail. Only Awana and aftermarket.

Sent from my SM-G950U using Tapatalk

Speedster
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Re: The BSA nail

Post by Speedster »

Loud2ns, Count your Blessings.
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whodathunkit
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Re: The BSA nail

Post by whodathunkit »

What about grooving the axle shaft’s
Or tapering the axle head’s

What’s worked best for me is knocking off the
Burrs at the axle tips . So I don’t Destroy
The wheel bores while Inserting axles.
Last edited by whodathunkit on Fri Jul 03, 2020 6:09 pm, edited 1 time in total.
What type of automobile can be spelled the same forwards & backwards?
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whodathunkit
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Re: The BSA nail

Post by whodathunkit »

Compound bends in the axle shaft!
What type of automobile can be spelled the same forwards & backwards?
Speedster
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Re: The BSA nail

Post by Speedster »

Live and learn.
This is the 1st time I have heard about "compound bends" in the shaft. Would you describe what is meant by that and what advantage it might give?
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whodathunkit
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The BSA nail

Post by whodathunkit »

Sure Speedster!

A two plane bend or compound bend is defined as a compound bend.
In the plane view and a bend in the elevation.

Think of tube bending!

The nail axle is not a tube..however it is a round and a solid shaft much like tubing
that can be bent in many different angles.

Example..

Take your axle ,a screwdriver , and a hammer, and a vise.
You want to bend the axle to 1.5 degree.
So you place it in a vise and tap the axle to bend it
With the screwdriver and hammer.

You take it out of the vise to check your bend angle.
You find you need to bend it a little bit more.

So you do the best you can to place it back in the vise the exact same way it was.

However it’s not.. and its rotated some what now!

So you start tapping and bending it some more.

However you have rotated the axle somewhat when you placed it back in the vise
and now you have a compound bend in the axle shaft.

Is it helpful.. I don’t think so !
Last edited by whodathunkit on Sun Jul 05, 2020 3:36 pm, edited 2 times in total.
What type of automobile can be spelled the same forwards & backwards?
Speedster
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Re: The BSA nail

Post by Speedster »

Yep, that would be a compound bend. Thanks for the explanation.
Kindintentions
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Re: The BSA nail

Post by Kindintentions »

Thanks for the explanations.

Kenny, I would love to know more about the Nickle plating process, even if it is just for fun, or something to do for a no rules race, any good websites or breakdowns of how to do it?
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Re: The BSA nail

Post by davet »

1) We would square our drill press table front to back and side to side.
2) Put axle in chuck just as far as it would be in the block of wood with a wheel. ( If you don't slide into chuck far enough the axle will bend during following steps)
3) Using a file that is smooth on edge we would file down the burrs under the head. If the file is textured on the edge it will damage shaft during this process.
4) Using same smooth edged file taper the head
5) Grab a file that has texture on the edge and is thick enough to cover both crimp marks at the same time, no thicker. Lay it on the press table right alongside the axle.
6) Raise the table so the file is lined up to contact both crimp marks at the same time.
7) Turn on drill press and lightly pull the file into the axle and remove the crimp marks. Keep going slightly beyond removing the crimp marks to get a nice groove. (VERY IMPORTANT: Table must be square to drill on both axis. Also while pulling file into the axle to remove crimp marks move the file from side to rear in order to keep the groove square)
8) Polish axle to your liking, including under the head surface and the face of the head. Why the face of the head too? Because nobody else does and it looks sharp.
9) Next bend your axles if you do that. If you use straight axles skip to step 11.
10) To bend polished axles I use a needle nose pliers. Use an old face rag and fold it over 3 times. Not 2 and not 4. Place the rag into the open needle nose pliers. Now you're squeezing the axle with the pliers lined with the rag. Put a wheel on
your axle and using a fine tip marker mark the axle at the inside of the hub. Mark a 12:00 position on axle head. Place the axle into the chuck up to the mark you made. Line up the 12:00 position mark facing you. Slide the needle nose
(works great because a needle nose is tapered) over the axle until it won't slide on anymore. Now bend the axle towards you, towards the 12:00 mark. If you need to add or remove bend angle always line the 12:00 mark facing you so you
don't get a compound bend.
11) Soak axles in 91% alcohol and wipe clean with soft cloth. Dry them with a hairdryer.
NEXT STEPS ARE FOR OIL:
12) Place them in precut holes in a scrap piece of wood with about 1/2" exposed.
13) Spray with your choice of coating like Jig or we always used 3M Dry-Type Silicone from Napa.
14) Place the block of wood in out of the way area and slide the wood into an open ziploc bag or if the axles are close enough together on the block of wood cover them with the cover from the silicone spray.
15) Leave covered until installation.
16) Put 2 drops of oil on your Tamiya swab and slide it through the wheel once. Using same swab rub a little oil on hub face and onto rear face of hub where it contacts the car.
17) Install axle/wheel combo and tune.
DONE.
**We placed 7th in Northernstar Council race using these axles.
**IMPORTANT: if the table isn't squared perfectly to the axle in the chuck, and you groove your axles. you will get a buzz and the wheel won't spin smoothly.
Last edited by davet on Sun Jan 03, 2021 6:28 pm, edited 1 time in total.
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davet
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Re: The BSA nail

Post by davet »

Not sure why step 8 has an emoji. Can't get rid of it.
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Re: The BSA nail

Post by gpraceman »

davet wrote: Fri Jan 01, 2021 10:48 pm Not sure why step 8 has an emoji. Can't get rid of it.
That's because some combinations of characters represent emojis. So, the 8 + ) = 8)

You can try 8 + . instead
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Re: The BSA nail

Post by murphken »

Wow! You guys really take your axles seriously! It takes me about 15 minutes to make nails into axles for non-lathe cut process. I use the speed of a Dremel and good sandpaper to my advantage. Several files are used to remove the crimp marks around the axle head.
I use good commercial sandpaper: 80, 150, 220, 400, 800 and 1000 grit. The 1000 grit has a film of dry wax applied. After inspection, I have to rework about 10% of the completed axles usually due to a remaining crimp mark on the axle head.
A dremel lasts me about one season. I wear-out about three collets/season. One season amount to about 350-400 axle sets. Sanding is completed in a cold garage. Inspection is completed under lighted magnification.-
I prefer sanding lathe-cut axles. Cycle time is about the same considering the addition of a lathe-cut. However, sanding/polishing takes less time. Need to have a lathe, with collet tooling, open for use, to cut axles.
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