BEACHJET CLASS RULES
Revised July 12, 2009
All of
these car rules state
modifications that are and are not permitted.
Any “modifications” performed on entered cars or controllers in
violation of these rules will make the car ILLEGAL and/or the racer disqualified. If anything is not specifically stated or
addressed in the following rules, it is NOT permitted.
Definitions
These following definitions
apply whenever the following words appear in the rules in CAPS:
STOCK: No
modifications other than those allowed in the rules are permitted.
STOCK REPLACEMENT: Aftermarket
part of similar design to the same STOCK Aurora Thunderjet
part.
No
modifications are permitted.
Commercially Available: Being
able to buy parts from the maker or a supplier.
Note: Although these definitions are self explanatory, examples of
prohibited modifications may be included in certain sections. These examples, in no way infer that other
modifications are permitted. Stock means
Stock, etc.
General
1.
The term “Car” shall refer to a chassis
and body combination and does not insinuate a specific body style.
2.
Motor vehicles with at least 1 wheel at
the four corners like sedans, sports cars, racing cars, trucks, emergency
vehicles, etc. are all legal.
3.
Cars must be legal at start and during
the heat.
4.
In case of part or body failure due to
race conditions, you will have to fix the car before being permitted to resume.
5.
One track call will be permitted per
racer per heat.
6.
Two track calls for the same failure will
not be permitted in the same race, even if in different heats.
7.
Repairs for duplicate failures will need
to be done during race time.
8.
A quick track call will only be permitted
to clear parts off the track. This is a
risk that is taken when building on the edge.
9.
Any car deemed detrimental to the track
(i.e. riding
the bottom of the slot, cutting into the slot, or greasing/oiling the track,
etc.) will be removed from the track and not permitted
to race.
10. The complete car must not weigh less than 19.0 grams
and no more than 23.0 grams.
11. Additives are not permitted to aid in traction. This includes glues, oils, dirt, dust or
saliva. Basically anything that will hinder
another cars performance in that lane.
12. The car must not leave anything on the track.
13. Conductive lubes are permitted in extremely moderate
amounts, and only under the brushes and where the pickup shoe meets the
chassis. These lubes must not deposit on
the track during racing or they will be deemed illegal.
14. Weight cannot be added to the bodies or chassis except
on the axles outside the chassis axle holes.
15. Handling pans are not permitted.
16. Traction magnets of any kind are not permitted.
17. Cars must pass freely and easily through the tech
block.
18. All 4 tires must touch the track at the same time when
at rest.
19. Only one guide pin is permitted per car and must
reside in original position. They may be
glued into original position.
20. Except where solder is permitted, lead is not
permitted anywhere on the car.
21. Lubrication of the chassis is permitted at any point
provided it does not make it to the track.
22. One false start is permitted per heat and will be
defined by the race host for the particular track being run.
23. Push starts are permitted at any time.
1
BODY
Requirements ONCE
A BODY IS TECH’D IN, IT CANNOT BE CHANGED
1.
Bodies must be of the hard shell variety
(no vacuum formed bodies) and manufactured by either the process of casting or
injection molding, and be made of resin or plastic.
2.
Bodies must be originally manufactured
with the intention of being mounted, with the use of 2 screws via the 2 body
mounting posts, on a/an: Aurora Model
Motoring (which includes Vibrator, Thunderjet, Wild
Ones, Tuff Ones and Xlerators), Bachmann, Faller,
Model Motoring Inc. Thunderplus, Marx, Eldon or Tyco “S” series “HO” chassis.
3.
Bodies must be fitted with all the manufacturer’s original bumpers, heads, rollover
bars, etc. in their stock locations.
Similar aftermarket replacement parts may be used.
4.
On a convertible body, any replacement
windscreen must be the same height and width of the body manufacturer’s original
windscreen.
5.
No body openings other than windows and
front grills are allowed.
6.
Body must completely cover the back
plastic of the chassis/gearplate, when viewed from
overhead.
7.
The front windshield must be made of
plastic and fill the entire frame. They
may be glued in place.
8.
There is no “on market” requirements for
bodies, but if a new body is introduced and has not been made publicly
available to the group in it’s present form 2 weeks prior
to the race, then it must be made available in sufficient quantity at the
race. 10 is a sufficient quantity.
9.
Maximum width is 1 5/16”.
10. Bodies must resemble cars that exist.
11. No blobs or boxes with lids.
Mounting
1.
Bodies must be mounted using the original
two-screw mounting points of the chassis.
2.
Cracked or broken body mounting posts may
be repaired or replaced with the use of glue and/or plastic sleeve around, or a
plastic tube in place of the broken post in the original position.
3.
Bodies must be mounted using two
screws.
4.
ANY screws may be used and left loose,
but must be tight enough to not fall out.
5.
Rear screws may be glued.
6.
No weight may be added to the bodies.
Modifications
1.
Bodies may be lightened by removing
material from the underside.
2.
Any holes caused by lightening must be
filled to original thickness.
3.
Bodies that have a separate roof and windshield
casting/molding, and have molded in “interiors” (also known as Hardtops, i.e.
Aurora’s ‘65 Mustang), may have the “interior” portion of the body completely
removed.
4.
Front wheel wells must not be modified in
such a way to allow the use of any other wheelbase than that which was
originally intended by the manufacturer of that body.
5.
Side windows may be removed but are not
permitted to be oversized to create a small roof.
6.
Lightened bodies must maintain original
outside appearance.
7.
No bubbles, warpage,
or excessive repairs.
8.
The body to chassis mounting posts may be
shortened to lower the body closer to the chassis.
9.
Bodies may be painted and/or
decaled.
10. Once a body has been tech’d
in, it cannot be changed.
Chassis
1.
Only STOCK Aurora Thunderjet
chassis with copper electrics are permitted.
This includes Flamethrower chassis.
2.
The chassis axle and armature holes may
be slightly opened up for increased clearance.
3.
Added bushings and bearings are not
permitted.
4.
The chassis may be trimmed slightly (no
more than .010”) to allow for crown gear tooth clearance.
5.
Chassis, gearing, and shafts may be
polished.
6.
Chassis cannot be cut, sanded, or drilled
in any other way unless stated in the rules.
7.
Chassis cannot be cut to allow
repositioning of magnets.
8.
Flashing due to the manufacturing process
may be removed.
9.
Rivets may be tightened.
10. Replacement rivets are not permitted.
Guide Pins
1.
Only STOCK Aurora black plastic or
similar black or gray replacement plastic guide pins may be used.
2.
Guide pins may be cut, trimmed or bent,
and may be glued into place.
3.
Guide pins may be trimmed to allow smooth
operation in the slot.
4.
Maximum guide pin length is ¼”.
5.
Rear, swivel or metal guide pins are not
permitted.
Magnets
1.
Magnets may be zapped.
2.
Magnet shims may consist of any material,
but may not be a permanent magnet.
3.
Shims must reside entirely inside the
magnet cavity.
4.
Permitted magnets are as follows:
ORIGINAL
Aurora, ORIGINIAL Thunderplus, Super Two’s, ORIGINIAL
Johnny Lightning , and Auto World magnuts
designed for a pancake style armature.
Tires, Rims and Axles
1.
All front or rear tire/rim/hub/axle
combinations are permitted.
2.
Must be commercially available at a
competitive price.
3.
Only the crown gear and crown gear shims
may reside on the axles between the chassis axle holes.
4.
Shim diameter cannot be larger than the
tail diameter of the gear.
5.
Crown gear shims must not interfere with
the rotation of the axle in any way.
6.
The center front axle truck hole may not
be used.
7.
Overall width must not exceed 1 5/16”
when rims are extended to their maximum width.
Electrical
1.
Pickup shoes must be STOCK copper Aurora
or any commercially available stock replacements.
2.
Pickup shoes may be bent, but must retain
a step at its’ original location.
3.
Pickup shoes cannot be weighted.
4.
Shunt wires, “tiger tails” or other
soldering on the bottom of the chassis is not permitted.
5.
Lighted chassis must have the light bulb,
clip, and wire completely removed.
6.
Pickup shoe springs must be ORIGINAL
7.
Pickup shoe springs may be shimmed with
armature spacers to increase spring pressure.
8.
Shims must fit completely inside spring
hole in the chassis.
Commutator Brushes
1.
ORIGINAL
2.
Brushes must be flat surfaced on top and
bottom.
3.
.060” - .075” in height and in the stock
position.
4.
Domed or silver brushes are not
permitted.
5. Cutting or drilling brushes is not
permitted.
6. Scoring brushes is legal.
Brush Springs
1.
Brush springs may be bent in any fashion
to allow different brush tensions and/or to stop brushes from rotating.
2.
No material may be added o or removed
from the brush springs.
3.
Glue may not be used under the spring to
increase tension.
4.
Brush springs cannot come in contact with
the commutator at any time.
Gearing
1.
Only STOCK Thunderjet
or STOCK REPLACEMENT 14 tooth armature gears are permitted, (comm. Available)
2.
Only STOCK Thunderjet
or STOCK REPLACEMENT, including Model Motoring, 24
tooth brass idler and driven gears are permitted, and any commercially
available gear.
3.
Only STOCK Thunderjet
or STOCK REPLACEMENT 9, 10, 11, 12, or 14 tooth brass pinion gears are
permitted.
4.
Only STOCK Thunderjet
or STOCK REPLACEMENT 15 tooth crown gears are permitted.
5.
The crown gear boss may be trimmed to
adjust for proper gear mesh.
6.
Gear tooth friction surfaces may be
de-burred by polishing, filing, or sanding.
7.
Beveling or removing material from the
gears is not permitted.
8.
SLIGHT rounding of the edges due to
polishing, filing, or sanding is acceptable.
9.
Gears may be glued or soldered to the
shafts.
10. Excessive glue or solder is not permitted.
11. Crown gear minimum size
to be .300 plus or minus 1 percent in size, ie. 297 -.303.
Gearplate
1.
Only STOCK Aurora Thunderjet
and Tuff Ones gear plates are permitted.
2.
Any amount of the vertical gear plate
rails may be removed.
3.
No part of the gear plate may be removed
below the plane of the top.
4.
Removal of gear post material is not
permitted.
Gearplate Clamp
1.
A STOCK copper Thunderjet
or STOCK REPLACEMENT gear plate clamp must be used.
2.
The clamp may be bent or dimpled.
Armatures
1.
Armatures must be STOCK Aurora Thunderjet.
2.
Thunderjet armatures are one, or a combination of copper, red or
green colored wire on gray colored laminations.
3.
Minimum resistance across any two commutator sections cannot be lower than 16 OHMS at an
average room temperature of 65 degrees to 75 degrees Fahrenheit.
4.
Re-wound armatures are not permitted.
5.
De-wound armatures are permitted.
6.
Commutators may be straightened and trued but must remain in the
stock position.
7.
No timing changes.
8.
Armatures may be balanced by adding
epoxy, or by removing metal from the laminations only.
Controllers
1.
ANY controller is permitted.