21st Century SdKfz 251 conversion to RC
Posted: Sun Mar 27, 2011 5:26 pm
Now that I have figured out how to strip this static model apart, I can post pictures of the first part of the conversion process.
Getting it apart was no easy task, as it is held together with spigots that are glued. There is no way of dismantling it without breaking the spigots off, so the process involves some haevy handed levering.
That said, as long as things are done in the right order, it does come apart without doing any damage that will be visible after reassembly.
I soaked the model in a sink full of very hot water before attempting this, as it softens the plastic and maybe melts some of the glue. You can see that the drivers seats have been removed, this isn't necessary as the whole floor pan will come out in one piece.
First, remove the side panels. These come off sideways. Very difficult to lever these off, as you have to keep going until the retaining spigots snap, but without damaging the side panels in the process.
Undo the four screws that are now visible, plus the two that are at the front. A bit more gentle persuasion and the upper hull will be released.
Hot water did the trick on the dash, this pulled out quite easily.
Likewise with the engine, this can be prised out.
Now the floor pan can be levered out.
The front axle can be unclipped.
...and finally the drive sprockets can be pulled out. Hot water definately saved the day here. Gentle pressure and the axles pulled out without damaging anything.
There are three retaining screws behind the roadwheels and I am guessing that once these are undone, the backplate will come off. I would then have clear access to install motors and a gearbox. I have a small scale Tamiya Leopard with a full function diff, and I have seen one of these slotted straight in there. Its very small, and flat, so I am hoping that I can make a neat job of it and reinstall the floor pan afterwards.
I did a bit more.
As mentioned I have a Tamiya Leopard that is sat here doing nothing, so having looked at it, it seemed that it would fit.
I was intending to remove the roadwheels, but then realised that the way that the Tam gearbox is constructed, I didn't need to do this in order to get the gearbox in. The main driveshaft isn't the driveshaft, it is only a shaft on which interlocking pinions rotate.
So, out with the dremel, and I ground down any mouldings that were in the way, and drilled out the hull to allow the pinions to be slid onto the shaft once the gearbox was installed. This means that I lose the mounting points for the roadwheel backplate, but there are still two holding it on, so it shouldn't be a problem.
I had removed the entire electronics from the Leopard so that I don't need to cut any wires. What amazed me was that all of the components fit like a glove right down in the lower hull of the Hanomag. I will 'almost' be able to reinstall the floorpan where it was, so the electronics will be totally hidden.
One showstopper for the moment is mounting the sprockets. These are free spinning on flanged pins on the original, but the Tamiya drive uses a double ended hex. One end slots into the sprocket, whilst the other has a slot in it that slots into the pinion on the gearbox.
The brass Tamiya one isn't long enough to bridge the gap between the gearbox and the Hanomag sprocket.
I think I have two options.
One is to cut the Tamiya one in half and use some soldered brass tube to lengthen it, the other is to make a new one using hollow brass tube with a slot in the end.
Either way, it will be over a week before I can do anything, by which time I will be back home and have ready access to the shops that sell this sort of thing.
Getting it apart was no easy task, as it is held together with spigots that are glued. There is no way of dismantling it without breaking the spigots off, so the process involves some haevy handed levering.
That said, as long as things are done in the right order, it does come apart without doing any damage that will be visible after reassembly.
I soaked the model in a sink full of very hot water before attempting this, as it softens the plastic and maybe melts some of the glue. You can see that the drivers seats have been removed, this isn't necessary as the whole floor pan will come out in one piece.
First, remove the side panels. These come off sideways. Very difficult to lever these off, as you have to keep going until the retaining spigots snap, but without damaging the side panels in the process.
Undo the four screws that are now visible, plus the two that are at the front. A bit more gentle persuasion and the upper hull will be released.
Hot water did the trick on the dash, this pulled out quite easily.
Likewise with the engine, this can be prised out.
Now the floor pan can be levered out.
The front axle can be unclipped.
...and finally the drive sprockets can be pulled out. Hot water definately saved the day here. Gentle pressure and the axles pulled out without damaging anything.
There are three retaining screws behind the roadwheels and I am guessing that once these are undone, the backplate will come off. I would then have clear access to install motors and a gearbox. I have a small scale Tamiya Leopard with a full function diff, and I have seen one of these slotted straight in there. Its very small, and flat, so I am hoping that I can make a neat job of it and reinstall the floor pan afterwards.
I did a bit more.
As mentioned I have a Tamiya Leopard that is sat here doing nothing, so having looked at it, it seemed that it would fit.
I was intending to remove the roadwheels, but then realised that the way that the Tam gearbox is constructed, I didn't need to do this in order to get the gearbox in. The main driveshaft isn't the driveshaft, it is only a shaft on which interlocking pinions rotate.
So, out with the dremel, and I ground down any mouldings that were in the way, and drilled out the hull to allow the pinions to be slid onto the shaft once the gearbox was installed. This means that I lose the mounting points for the roadwheel backplate, but there are still two holding it on, so it shouldn't be a problem.
I had removed the entire electronics from the Leopard so that I don't need to cut any wires. What amazed me was that all of the components fit like a glove right down in the lower hull of the Hanomag. I will 'almost' be able to reinstall the floorpan where it was, so the electronics will be totally hidden.
One showstopper for the moment is mounting the sprockets. These are free spinning on flanged pins on the original, but the Tamiya drive uses a double ended hex. One end slots into the sprocket, whilst the other has a slot in it that slots into the pinion on the gearbox.
The brass Tamiya one isn't long enough to bridge the gap between the gearbox and the Hanomag sprocket.
I think I have two options.
One is to cut the Tamiya one in half and use some soldered brass tube to lengthen it, the other is to make a new one using hollow brass tube with a slot in the end.
Either way, it will be over a week before I can do anything, by which time I will be back home and have ready access to the shops that sell this sort of thing.
