Removable wheels
Revised September 19th 1996

This tip is mainly for the F1 model. This may also work for some of the older sportscars but a lot of fiddling will have to be done.
Why would you want to do this you ask? Well if you are a model nut (idiot?) like I am you would want to take the wheels off to show off the brake system you superdetailed.
Another way to show off the brake detail on a F1 car is to have the car on dummy wheels. Modellers is the only aftermarket people I know of for 1:20 scale dummy wheels. Be warned that each team has different styles of dummy wheels. For 1:24 and 1:12 you will have to do some scratch building and casting.
A lot of people also go gaga when they see the small nut come off. A "relatively" simple procedure that gets excellent results

In most of the F1 kits there is some sort of system to get the wheel on and off. Most has to do with a friction fit. The newer Tamiya 1:12 kits have a nut that is used to hold onto the wheel. (Ferrari 641/2, McLaren MP4/6, Williams FW14B)
What we want to do is recreate the same situation for the other kits. The only other kit I know that has this nut onto a thread situation is the Modellers Ferrari 92AT 1:20.
The hardest part is to find a nut and bolt the correct diameter for the model you are using it on. A 4-40 bolt (a technical term that you will see in hardware stores) seems the ideal size for some 1:20 scale kit. The only problem with this is that the thread is not fine enough for the scale. It will work but will look a bit off
Some scrounging around may be needed to find the right thread and nut. The nuts and bolts used in the electronic industry are pretty good. You can get some of the stuff at places like Radio Shack.

1. The diagram above shows the cross section of the kit parts. This represents the Tamiya Ferrari 312T3 1:20. Other kits may be slightly different.
2. The second drawing shows the placement of the bolt through the upright. In this case the bolt is longer then we need and will have to be cut down later. Do not glue the bolt in yet. The kit driveshaft will have to be cut down but will cover the backside of the upright.
3. In this kit the nut was molded in so a hole has to be drilled in the kit part for he new bolt to fit through.
4. In this case the bolt was too long and had to be cut to size. Also in this case the area where the polycap was had to be filled in to make the wheel solid


When you have found the bolt you have to install this into the upright from the kit. Usually this is easy to do since there is a hole there for the kit part already. Most bolts will have to be cut to the correct length. I usually use a Dremel type tool with a cutoff wheel.
1. Thread a couple of nuts on then clamp off the end you don't need. The clamp will normal damage the thread so don't clamp off the part you want to keep. You could also clamp onto the bolts
2. After cutting the burrs will have to be cleaned up or the nuts will not go on and off easily
3. The edges of the bolt end should be filed to take as much of the burrs off as possible
4. This final step of taking off the nuts will clean up the final junk in the thread and give you a clean bolt.

A recess will sometimes be needed for the head of the bolt but this can usually be made from behind the upright. Once this is done the back can be puttied over and cleaned up.
To make it rotatable you will have to try and use the kit system in place. You may have to cut the head off the bolt so it can thread into the polycap supplied in most kits. Not an easy thing to do unless conditions are perfect (thread fits perfectly and snugly into polycap) My recombinations to forget the rotating bit and make it static. Hell I would love to make the wheels rotate and see the brake disc rotate at the same time but I would like to finish my model this century

The wheels in the kits vary from year to year. Some have holes for the kit bolt while others have the bolt molded in (most 1:24) For the ones with the holes, this area is done. For the kits with the modified in nuts you will have to drill the holes out and carefully sand the nut off. (Not easy or fun to do)
The nuts supplied with most bolts are a bit too big. For a more scale appearance you may have to file it thinner and maybe even reduce the diameter

Even more detail
If you look at the thread of an F1 Car you will see that on some the edges are tapered. This allows the wheel to be centered easier during a quick pitstop. So on your bolt you should try and bevel the edge. One way is to chuck it into a drill and rotate on a grinding stone or some other rough object. When most of it has been ground off go back over it with a fine file to give it a cleaner finish
Also on these nuts the center is hollow. What does this mean? If possible you should try and drill out the center. Lets just say this is not easy. See below for an easy solution.

Not wanting to drill out bolts I was trying to find an easier solution and here it is. I was wandering what has a thread with a hollow center and it dawned on me that toggle switches are like this. Switches and stuff for computers are very small. The nuts that come with some of these are also small and thin. The hardest part of this again is that you have to find them. A lot of the threads are not completely round as most have a slot or is flat on one side of the thread


Here is a sample disassembly of a switch for the threaded section we want for our kit. In this case the upright had to be carefully drilled out to take the body of the new part. The whell also had to be modified to take the new thread and nut.


When choosing a switch you have to make sure the thread is completely round. Most switches have a notch on the threaded section. This is used to keep the switch body from rotating when it is being mounted

For 1:24 the scale is that much smaller and the hollow thing could be ignored. Haven't seen a switch this small. A source for these bolts is the local hobby or train store. They usually have a rack filled with different size nuts and bolts. Some also have the tools to cut a thread for your bolt

A warning for this procedure is that because you are modifying the kit parts the finished product may be bit out of alignment. This means on the finished product the wheel may be out of alignment.

For older cars they had knockoffs. These are usually in various shapes. To get this to work a lot more scratchbuilding will have to be done.

Since surgery is usually needed for this procedure there is no going back once you started so plan you moves before cutting. Needless to say the results are worth it.

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