Method for Tiger I Steel-Wheel Conversion (Pictures below for Reference)
This is a method for fabricating Steel-Wheels as replacement of the rubber road wheels on the Tamiya Tiger I (56010 kit). Parts utilized are from the King Tiger (56018 kit) and can be ordered individually from Tamiya for less than 100 USD. This modification requires some advanced modeling skills.
This modification is best performed on an unassembled Tiger I kit but can still be accomplished from a built model. If reworking a built model, remove all the rubber roadwheels by loosening the set screw and extracting the axel assembly from the suspension arms. Set the wheels aside, these will not be modified or used for this conversion.
The roadwheel suspension arm axel mounting holes will need to be increased in diameter (reamed) to accept the Steel-Wheel assemblies. This step is best done with a drill press with the suspension arms removed from the tank. The modification can be done without removal provided extreme care is used to align the holes accurately. This procedure is detailed in Step 17 below.
Tamiya Parts Required:
9465605 SCREW BAG ‘D’ 1
9415939 SHAFT BAG 1
9415937 WHEEL BUSHING 1
9405055 ROAD WHEEL 1
0005923 PARTS ‘A’ SPRUE 6
Other Parts Required:
1/4 inch ID Nylon washers (or metric equivalent) 8 (about 1/32-3/64 inch thick)
#8 steel Washers (or metric equivalent ) 24 (thin walled)
Minimum tools needed:
Needle-nose pliers with side cutters
6” Coping saw with fine blade (or slow speed table reciprocating saw)
100 grit sandpaper
Ruler or measure
CA (cyanoacrylate) glue, medium viscosity
Variable speed Drill (or Drill Press) and 5/32 inch bit (or metric equivalent)
Important Note : Do not throw any pieces away. Most all of the material will be used in this conversion; the scrapes of one assembly are actually used for another assembly later. Be careful cutting and assembling, there may not be extra parts if a piece becomes broken, cut or glued incorrectly.
Step1: Glue each aluminum wheel to each plastic wheel with CA glue being sure to center the wheels with respect to each other. The screws from BAG ‘D’ may be used to help align the wheels but do not mount or glue the screws. The wheels assemble similar to the King Tiger kit.
Step 2: Break off with needle-nose pliers, or cut the three plastic stand-offs with a modeling knife from all Inner roadwheels (the wheels without bolt detail) flush with the aluminum wheel. Refer to Picture 1 below.
Step 3: Carefully cut the hub of all Outer roadwheels (the wheels with bolt detail) flush with the aluminum wheel. Keep all the cut hub pieces. Cut off the three mounting tabs from each cut hub piece and trim smooth. Lightly sand the cut end of the hub to assure it is flat (planned). Light sanding provides a slightly abrasive surface for the glue to bite into for attachment of successive pieces. Eight of these modified hub pieces are used in Step 4 and Eight are used in Step 10. Refer to Picture 1 below.
Steps 4-8 details the Inter-Leaved Roadwheel construction:
Step 4: Mount the modified hub piece to the Inner roadwheel (bushing insert side in) with the brass bushing in between with the bushing insert to the face of the wheel. Secure the brass bushing and modified hub with CA glue. Make only Eight wheels in this manner. Be careful glue does not enter where the axel slides through the bushing or against the rear of the brass bushing. Refer to Picture 1 below.
Step 5: Cut the long hub extender at 9/16 inch from the bushing end. Make only Eight hub extenders in this manner. Lightly sand the cut end of the long hub extender to assure it is flat (planned) and to add a bit of abrasion for successive pieces to be attached. Refer to Picture 1 below.
Step 6: Insert the short axel shaft into the Inner roadwheel bushing from the back side and add grease. Enclose the axel with the cut long hub extender fitted in the modified hub collar verifying a dry fit first, then apply CA glue using care not to allow glue inside the hub where the axel and grease will reside. Make only Eight in this manner. Refer to Picture 1 below.
Step 7: Attach the Outer roadwheel backside to the cut end of the long hub extender with CA glue. Be careful to align the center of the hub assembly with the Outer roadwheel. Make only Eight in this manner. Refer to Picture 1 below.
Step 8: Attach the hub caps to the ends of the Outer roadwheels with CA glue in similar fashion as the King Tiger assembly. Do this Eight times. See Optional Step 16 for end cap detail.
Steps 9-14 detail the Double Roadwheel construction:
Step 9: Cut the self-tapping screws from Screw Bag ‘D’ with side cutters down to 1/4 inch measured from the head. Repeat procedure for 24 screws.
Step 10: Mount the remaining modified hub pieces (from Step 3) to the Outer roadwheel rim collar (bushing insert side in) with CA glue. Make only Eight wheels in this manner. Refer to Picture 3 below.
Step 11: Mount a brass bushing in each Outer roadwheel with the bushing insert to the face of the wheel. Secure the brass bushing with CA glue. Make only Eight wheels in this manner. Be careful glue does not enter where the axel slides through the bushing or against the face of the brass bushing. Refer to Picture 3 below.
Step 12: With CA glue, add a 1/4 inch nylon washer (roughly 1/32 inch thick) to the void of the Inner roadwheel to bring the surface up to aluminum wheel thickness. Attach the Inner roadwheel to the Outer roadwheel back to back with CA glue and align and secure with three self-tapping screws (modified in Step 9) from Screw Bag ‘D’ using washers as spacers between the wheels for each screw. This slight gap created between the wheels by the bushing and washers is intentional to provide adequate spacing for track alignment. Repeat this for Eight wheels. Refer to Picture 3 below.
Step 13: Insert the long axel shaft through the face of the Outer roadwheel with two #8 washers between the axel stop ring and the Outer wheel bushing then add grease. Refer to Picture 4 below.
Step 14 : Using the Sprocket end caps, cut the molded nut off and insert a steel bearing, insert side in first, seating completely. Add one #8 washer on the axel end add more grease and enclose with the bearing seated Sprocket cap. Assure axel alignment and attach the Sprocket hub caps to the end of the modified hub extenders on the Outer roadwheels with CA glue. Do this Six times. Two of these end caps will need to be fabricated from the roadwheel hub extenders since only six Sprocket end caps are on the sprues to complete eight double roadwheel assemblies. See Optional Step 16 for end cap detail. Refer to Picture 4 below.
Step 15: Use the two remaining hub cap extenders (from Step 5) and cut the end cap detail off and shorten the hub to 1/4 inch measuring from the large ring to match the Sprocket end cap length. Repeat this step twice. Note: this Step can be omitted if one prefers to obtain two additional "Sprue A" parts with additional Sprocket end caps.
Step 16 (Optional): For more realism the hub cap end detail may be shaved down and built up to better resemble the end caps on the actual Steel-Wheel Tiger, since the present detail is of a King Tiger end cap. This detail modification is left to the modeler. Refer to Picture 5 below.
Step 17: Using a drill press, increase the diameter of the Tiger I roadwheel suspension arm axel mount holes to 5/32 inches (5/32 drill bit). Use a slow speed to avoid excessive heating, jamming the bit or throwing the piece across the room. Perform this procedure for 16 suspension arms (do not modify the idler suspension arm). Be sure to back off and remove the set screws before drilling. Remove any metal burs and flashing.
Step 18: Install the new wheel assemblies using the Tiger I instructions as a guide and align the flats of the shafts with the set screws when tightening. Use the track positioned between the sprocket and idler to ensure alignment of roadwheel assemblies. It is recommended to use Lock-Tite on the set screws to prevent backing out once alignment and test run is done.
The conversion is a challenge but the results are beautiful!