MRC THUNDER KING PARTS - Compatible with Desert Thunder and Baja King.

*This set does not include Ball End Joints or any plastic shock/gear components.

I started this project just needing to replace the Nose Piece and eventually I made replacements for all the plastic parts on the truck. It may be important to note that the Desert Thunder (Buggy), the Baja King (Racing Truck) and the Nitro/Electric Thunder King almost use all these same parts in their Chassis variations.... other than listed here:  Nitro Thunder King uses a different Rear Axle Carrier with larger bearings and uses a different transmission housing.  The Wheels/Tires, Shock Towers, and Body Mounts differ between the King, Desert, and Baja models. (as well as different pinion/spur combinations)

These parts are designed with tolerances for PETG. You may have success with PLA but I have not tested the parts for PLA.  I'm pretty sure the tight tolerance parts that use bearings will not fit using PLA.

All parts have been named the same as they are in the Assembly Manual.  I also made and included a PDF of the complete Thunder King Assembly Manual for both Electric and Nitro & the Fine Tuning Pages for the Desert Thunder and Baja King. 

While I have included the Servo Saver A & B parts, PETG has not been strong enough to survive use and the part will break. Perhaps trying PC or another material will allow them to work.

The best info on Thunder Kings I have found online is HERE on RCUniverse. (User "The Boss" is full of TK knowledge!)

MY THUNDER KING WHEELS

MY REAR BUMPER WALL MOUNT TK/DT/BK

MY DESERT THUNDER BODY

MY DESERT THUNDER WHEELS

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--Further info and instruction--

Most all parts are rebuilt as original as I could, SOME geometry has been changed, filled in or overbuilt. For example I have filled in several "ribbed areas" as it makes the part stronger with little weight difference and some injection molding limits are not needed on these 3D printed parts.  The important geometry such as connecting points for rods, screws, bearings, shafts, etc. have all been made as tight and clean as I could.  *IMPORTANT see photos for shaft/axle through holes that must be cleared with drill bits. Several parts have a Left and Right so look for the L on matching parts. (Right parts are unmarked)  I have edited both bumpers to be two pieces instead of one, and the battery holder has been opened a bit vertically to allow modern battery packs/hard case packs to fit. There is a missing redundant Spacer for the Nose Piece.

The only part that is not like the original is the Radio Tray. The original was overbuilt and designed for a mechanical servo driven speed control which were paired with old am radios and just not used much anymore.  So I made the tray smaller to attach a ESC and/or a switch.

There is a Reinforced Version of both the left and right Transmission Housings, it is overbuilt around the chassis mounting holes to help the part from splitting when tightened to the chassis.  Using a tap to first thread the holes may help as well.

I have added my own part called TK_Motor-Plate-Plug that can be used to cover the second (top) motor mount location and eliminate debris from getting inside the pinion/spur gear cover.   I know there is discussion about only using two motors at a time for gear wear/life but I have not had a problem with using only one brushless in the bottom position.  Two brushless motors/esc on one of these 2wd trucks is wayyy too much imo, it screams with one 3500kv, 5000/30c 7.4v 2cell lipo, and a 14 tooth Pinion... runs about the same as a Nitro Version.

*As mentioned above the through holes of the front and rear arms, the nose piece shaft holes, and areas on the Spindle-Blocks and Front-Hub-Carriers must be drilled out after printing.  Not much material is removed but just enough for the tight tolerances needed with these parts. The three drill bit sizes needed for this are 7/64 (2.778mm), 1/8 (3.175mm), and 5/32 (3.969mm). See the photos for more.

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--Printing Info--

I have included my .3MF files that have several tray settings and part specific support settings I suggest for best fitment of all parts. One tray of supported parts, one with no supports, and one tray for the Transmission Housing with very minimal supports. The only part with difficult support removal is the Gearbox Cover but they will remove clean with some effort.  All parts have thick top and bottom layers as well as perimeters, I do not suggest changing this as its intended for strength and proper size for thread and through holes.  Delete everything not needed on a tray and print what's left or set up the stl's your way.

• Filament:  Prusament PETG Anthracite Gray, and Jet Black

• Printed On:  MK3S+ (probably prints faster on a newer machine)

  Print Bed: Textured Powder Coat Steel Sheet

  Bed Temp: 90c

  Nozzle: 0.4mm

  Nozzle Temp: 250c

  Layers: .030mm (.007in)

  Infill: 30% Rectilinear

  Perimeters: 6

  Solid Layers Top: 5

  Solid Layers Bottom: 5

• Supports:  I use these settings from BOBSTRO on the Prusa Forums and they work well for me, on                        both PLA and PETG.

  Style: Snug/Organic

  Top Contact Z Distance: 0.25mm 

  Pattern:  Rectilinear

  Pattern Spacing:  3mm

  Top Interface Layers:  4

  Interface Pattern:  Rectilinear

  Interface Pattern Spacing:  0.2 mm

  XY Separation: 75%

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One last note.... These parts are intended as a last possible solution to fix or restore these old RC trucks so they can be used and enjoyed again.  I did a lot of printing and testing, they are not perfect and can probably be improved, but should be functional.  While you can print a full set of parts, more success may be found in using a part or two for repairs.  There is no other source to purchase parts for these vehicles except being lucky enough to find used or NOS stuff from places like Ebay and flea markets.  Keep in mind these are only the plastic parts so owning a previous assembly or kit of the truck is pretty much necessary as there are many sets of hardware needed to assemble the full model not to mention the aluminum chassis plate.  Enjoy!