Post by Andrew Rowland on Jan 10, 2016 12:18:30 GMT -5
Hi Folks
You will be aware of the SRC release of the Ferrari 312T4 and the Renault RS10. You will also be aware that Policar have released the Lotus 72 with the associated gearbox now available.
I am designing 3D printable chassis that will be available from Shapeways direct to you that allow quick and simple conversion of the SRC cars (and potentially Fly cars later) to Policar competition specification.
Two things have come together to make this happen:
1. The fact that the Policar Gearbox parts are now available through various shops. I will do a how-to below on what parts you need although you should view the www.Policar.it website for how to actually assemble the gearbox properly.
2. I have tested the prototype and the chassis is now available to buy.
So:
1. You will need:
a) A Shapeways chassis available here:
www.shapeways.com/shops/arco_chassis
b) Policar parts numbers necessary to complete the gearbox:
PC-H03 - motor mount
PC-PPA01 - set of bushings
PC-PGS8018/17/16 - rear axle with gear. note choose either of the 18/17/16 denotes which gear you prefer. standard cars come with the 17 tooth version.
PC-PGI2516-PL - crown gear and spacers
PC-PPI429015 - pinion
PC-H04 - motor mount screws - The gearbox has a unique screw fixing so you will need these whatever motor you wish to use (see also below).
c) Policar parts numbers I suggest but that might be interchangeable:
PC-PMX01 - motor. Note that the Policar gearbox has a single central top screw fixing position and so if you don't use this motor make sure yours has this hole! Also potential club rules might legislate for a single motor formula in due course.
PC-PPA02 - rear axle stopper - you may choose to use other types but be careful with sizes and what will fit.
PC-H05 - gearbox to chassis fixing screws - these are the correct size but other Slot.it (and potentially other) types will also fit.
d) Other parts to complete the build:
Rear wheels and tyres
I have used Ostorero Lotus 79 wheels and tyres as I have them and because they are round and grippy.
The RS Scalextric replacement aluminium hubs available through pendles are a good option as the hub in this case does not get in the way or look too bad. Tyres to fit are probably available from various producers.
If someone wants to make suggestions please help.
The design parameters are that they should be about 21mm dia. and 14-16mm wide. to match the ones on the model.
e) Front wheels and tyres:
I have used the original tyres for the cars as they are quite hard (good for low grip) and of a unique size for the car. I have struggled to find suitable aluminium grub screw fixing replacements so if anyone has any or knows of any please help!
Wheel size is 9.5mm wide, 10.7mm dia. of wheel and 12.4mm dia. of central raised section. Central raised section 5mm wide in centreline of wheel.
In an ideal world I would take the wheels that come with the car and cut them down to make them into inserts into aluminium wheels.
Actually I found that original 1970's F1 Scalextric front wheels are the right diameter and width and many of you will have them laying about!
The only rub is that the central 'seating band' is too thin so ultimately they will need to be glued on and potentially trued.
They need to be silver but the ones on my build are black currently.
f) Front axle
Any normal axle should work.
g) Guide etc.
The Policar range is designed to use the Slot.it CH85 screw in pick up. Others may fit to your choice.
Wire.
Braids (thin as possible suggested).
Eyelets or grub screws to your choice.
How To:
Start by removing the chassis from the body on the donor car.
Once disassembled remove the front tyres from the donor car and set aside the 4 body fixing screws.
This model is designed so that all of the wings etc. are fixed together so the interchange is very simple.
Once you have the gearbox and motor mount completed you can screw it direct to the new chassis.
Note that the motor mount has two forward fixing screws. On this model both are not needed. The bottom of the driver's seat will foul the foremost screw fixing position on the motor mount. You have two choices:
1. Remove the front screw fixing part of the motor mount so you have three motor mount fixings only. Before doing this consider whether you may use this motor mount on other cars where you might wan this forward fixing.... Because....
2. The alternative is to leave the motor mount whole and cut out the central bottom seat position from the Ferrari.
I chose to cut off the motor mount forward fixing as it is frankly easier and quicker.
This photo shows the old chassis go in the parts bin, the motor mount minus front fixing already screwed to the chassis,the complete body and some screws for body mounting. I would use the original screws if I were you but I used Policar ones since I had them.
Once the chassis is assembled you can offer it up to the body. You will see that the gearbox fouls the rear bodywork of the bodywork right at the back.
When test fitting alignment you should use the front upper suspension arms to make sure things are aligned well. The frontmost suspension arm should fit absolutely centrally into the recess in the original body. The slotted body fixing screw holes will be at a maximum of one end of the slot when this happens.
At the rear you will need to cut away some elements of the donor car detail. This is minimal and will not affect the overall aesthetic if one wants to ever return to the original chassis configuration. Collectors might not want to do this so make sure you think it through before proceeding.....
I show three views of the elements to cut off. Experienced model makers will want to think it through themselves but hopefully the photos are clear enough to enable you to cut the right parts out. Remember cut less, try, cut more, try again and so on to get the right amount out.
When flipped over none of this cutting is visible as these elements sit under the black air intakes and are essentially side parts of the gearbox. So no aesthetic value is really lost.
I used a sharp new scalpel blade to cut a line and then a fine nosed pair of pliers to gentle snap out the various bits. Wiggle the part back and forward and potentially cut a few times. Do this gently with patience, don't be wrenching bits off or the whole body will crack up. Maybe use superglue underneath if bits fall apart. I found the two black air intakes just fell off mine before I started so they got glued in underneath.
Once seated the car should look like this:
If you like you can cut the far rear part of the Policar gearbox off. I have left it for future potential reuse on other cars.
As mentioned the front wheels are off an old Scaley F1:
Obviously add the guide, wires etc. At this stage before final assembly.
Screw the top and bottom parts together only once you see that the four body screw positions sit down without you needing to press them. Check the rear gearbox is free of the bodywork by spinning the rear axle by hand once it is all screwed down.
EDIT:
A word of CAUTION:
I have discovered that my conversion chassis is allowing the body mounting screws to go deeper into the body than the original chassis did. This will mean that if you screw hard into the body you might get the screw head making a little 'blip' in your shiny body top. I did!
So please either cut the head off the screw or use shorter crews.....
End Edit:
Assemble front axle, rear wheels and tyres, flip it over and...... The car should now look like this:
It sits nice and level and low, and looks the part in my view. Pity about the black wheels, i'll have to paint them silver to reflect the real car!
I have not fitted the side skirts but the original ones should fit in.
Cheers
Andi
You will be aware of the SRC release of the Ferrari 312T4 and the Renault RS10. You will also be aware that Policar have released the Lotus 72 with the associated gearbox now available.
I am designing 3D printable chassis that will be available from Shapeways direct to you that allow quick and simple conversion of the SRC cars (and potentially Fly cars later) to Policar competition specification.
Two things have come together to make this happen:
1. The fact that the Policar Gearbox parts are now available through various shops. I will do a how-to below on what parts you need although you should view the www.Policar.it website for how to actually assemble the gearbox properly.
2. I have tested the prototype and the chassis is now available to buy.
So:
1. You will need:
a) A Shapeways chassis available here:
www.shapeways.com/shops/arco_chassis
b) Policar parts numbers necessary to complete the gearbox:
PC-H03 - motor mount
PC-PPA01 - set of bushings
PC-PGS8018/17/16 - rear axle with gear. note choose either of the 18/17/16 denotes which gear you prefer. standard cars come with the 17 tooth version.
PC-PGI2516-PL - crown gear and spacers
PC-PPI429015 - pinion
PC-H04 - motor mount screws - The gearbox has a unique screw fixing so you will need these whatever motor you wish to use (see also below).
c) Policar parts numbers I suggest but that might be interchangeable:
PC-PMX01 - motor. Note that the Policar gearbox has a single central top screw fixing position and so if you don't use this motor make sure yours has this hole! Also potential club rules might legislate for a single motor formula in due course.
PC-PPA02 - rear axle stopper - you may choose to use other types but be careful with sizes and what will fit.
PC-H05 - gearbox to chassis fixing screws - these are the correct size but other Slot.it (and potentially other) types will also fit.
d) Other parts to complete the build:
Rear wheels and tyres
I have used Ostorero Lotus 79 wheels and tyres as I have them and because they are round and grippy.
The RS Scalextric replacement aluminium hubs available through pendles are a good option as the hub in this case does not get in the way or look too bad. Tyres to fit are probably available from various producers.
If someone wants to make suggestions please help.
The design parameters are that they should be about 21mm dia. and 14-16mm wide. to match the ones on the model.
e) Front wheels and tyres:
I have used the original tyres for the cars as they are quite hard (good for low grip) and of a unique size for the car. I have struggled to find suitable aluminium grub screw fixing replacements so if anyone has any or knows of any please help!
Wheel size is 9.5mm wide, 10.7mm dia. of wheel and 12.4mm dia. of central raised section. Central raised section 5mm wide in centreline of wheel.
In an ideal world I would take the wheels that come with the car and cut them down to make them into inserts into aluminium wheels.
Actually I found that original 1970's F1 Scalextric front wheels are the right diameter and width and many of you will have them laying about!
The only rub is that the central 'seating band' is too thin so ultimately they will need to be glued on and potentially trued.
They need to be silver but the ones on my build are black currently.
f) Front axle
Any normal axle should work.
g) Guide etc.
The Policar range is designed to use the Slot.it CH85 screw in pick up. Others may fit to your choice.
Wire.
Braids (thin as possible suggested).
Eyelets or grub screws to your choice.
How To:
Start by removing the chassis from the body on the donor car.
Once disassembled remove the front tyres from the donor car and set aside the 4 body fixing screws.
This model is designed so that all of the wings etc. are fixed together so the interchange is very simple.
Once you have the gearbox and motor mount completed you can screw it direct to the new chassis.
Note that the motor mount has two forward fixing screws. On this model both are not needed. The bottom of the driver's seat will foul the foremost screw fixing position on the motor mount. You have two choices:
1. Remove the front screw fixing part of the motor mount so you have three motor mount fixings only. Before doing this consider whether you may use this motor mount on other cars where you might wan this forward fixing.... Because....
2. The alternative is to leave the motor mount whole and cut out the central bottom seat position from the Ferrari.
I chose to cut off the motor mount forward fixing as it is frankly easier and quicker.
This photo shows the old chassis go in the parts bin, the motor mount minus front fixing already screwed to the chassis,the complete body and some screws for body mounting. I would use the original screws if I were you but I used Policar ones since I had them.
Once the chassis is assembled you can offer it up to the body. You will see that the gearbox fouls the rear bodywork of the bodywork right at the back.
When test fitting alignment you should use the front upper suspension arms to make sure things are aligned well. The frontmost suspension arm should fit absolutely centrally into the recess in the original body. The slotted body fixing screw holes will be at a maximum of one end of the slot when this happens.
At the rear you will need to cut away some elements of the donor car detail. This is minimal and will not affect the overall aesthetic if one wants to ever return to the original chassis configuration. Collectors might not want to do this so make sure you think it through before proceeding.....
I show three views of the elements to cut off. Experienced model makers will want to think it through themselves but hopefully the photos are clear enough to enable you to cut the right parts out. Remember cut less, try, cut more, try again and so on to get the right amount out.
When flipped over none of this cutting is visible as these elements sit under the black air intakes and are essentially side parts of the gearbox. So no aesthetic value is really lost.
I used a sharp new scalpel blade to cut a line and then a fine nosed pair of pliers to gentle snap out the various bits. Wiggle the part back and forward and potentially cut a few times. Do this gently with patience, don't be wrenching bits off or the whole body will crack up. Maybe use superglue underneath if bits fall apart. I found the two black air intakes just fell off mine before I started so they got glued in underneath.
Once seated the car should look like this:
If you like you can cut the far rear part of the Policar gearbox off. I have left it for future potential reuse on other cars.
As mentioned the front wheels are off an old Scaley F1:
Obviously add the guide, wires etc. At this stage before final assembly.
Screw the top and bottom parts together only once you see that the four body screw positions sit down without you needing to press them. Check the rear gearbox is free of the bodywork by spinning the rear axle by hand once it is all screwed down.
EDIT:
A word of CAUTION:
I have discovered that my conversion chassis is allowing the body mounting screws to go deeper into the body than the original chassis did. This will mean that if you screw hard into the body you might get the screw head making a little 'blip' in your shiny body top. I did!
So please either cut the head off the screw or use shorter crews.....
End Edit:
Assemble front axle, rear wheels and tyres, flip it over and...... The car should now look like this:
It sits nice and level and low, and looks the part in my view. Pity about the black wheels, i'll have to paint them silver to reflect the real car!
I have not fitted the side skirts but the original ones should fit in.
Cheers
Andi