12th scale help - Page 2

mark christopher · #21 15-09-2015

id go with xracers recommendations on size

tom00182 · #22 15-09-2015

Also does anyone have any tips for cutting out and mounting bodyshell (in terms of positioning )

mark christopher · #23 15-09-2015

ill post some help tomorrow, is it painted or clear?

1st best tip is mark and cut before you paint it

tom00182 · #24 15-09-2015

It is clear

Chequered Flag Racing · #25 16-09-2015

Here's video one of three on LMP12 setup from top racer Robert Krens.

Xracer · #26 16-09-2015

Now this is a topic that will bring lots of different approaches so I will table this one as a beginners starting point but you will see that there is equipment that you can buy or make to make the task very easy.

You also need to be aware that some shells are not very accurately marked especially the positioning of the front wheel arches relative to each other.

So start by trimming the side sills 4mm below the cut line, you can trim the front splitter and rear valance (assuming GT12 here) to the line but leave the wheel arches intact.

The 4mm surplus allows the shell to sit on your work surface when positioned over the car without the body posts fitted, the car should be set at its ride height of 3.5 - 4mm, you can then move the shell around to align the front wheels within the marked wheel arches, it is here were you will see how good the shell is marked!

The rear arches invariably do not align depending upon the wheelbase the shell was designed for originally and you may have to compromise on the fore and aft positioning!

Take a marker pen and mark the centre of each wheel axle as accurately as you can.

The best way to cut the arches is to use a compass cutter available from some model shops, online and elsewhere, set the size to clear your chosen tyre diameter, I go for around 3mm clearance, then trim the arches to complete along with the sills, smooth the edges of the arches at least, the shell can cut a tyre on impact.

The body post mounting holes can be done numerous ways, some choose to do them before the arches which I do now as I have made some adjustable posts that I can raise to sit the shell at the right height, on top of each is a small button magnet now sold by some of the model car dealers.

So I adjust each post to set the trimmed shell level with the chassis, i.e. 4mm above the work surface, drop a button magnet on top of the shell at each post, these magnets have a hole through their centre, align the shell and mark the post positions. I would then mark the wheel arch centres at this stage too.

I hope this all makes sense, it is an onerous task until you get your methodology sorted so do more then one shell, you will soon need a second one, I do three or four at a session and paint them too! Yeah I crash a lot!!!

tom00182 · #27 16-09-2015

Okay thanks for the advice.
Thanks for the video chequered flag racing. I have watched it already but it is all a bit double Dutch to me at the moment

mark christopher · #28 16-09-2015

My way is to cut body to lower cut line, rest body on car and Mark body posts, make holes with body reamer, mount body and adjust hieght of posts to correct posistion, then mark the centre of each axle/wheel nut, use a compass cutter, don't cut just score and flex and peal apart

Xracer · #29 17-09-2015

Mark's method is indeed tried and tested but only if the body posts are already set at the right heights for the body to sit parallel to the work top.

If it is your first shell on a new car or a different style shell on an existing car the posts will not yet be set to suit the body style, so ensure the shell is set level or the wheel arches will end up miss-positioned.

beale · #30 20-09-2015

Start with them as they are your not looking at winning everything! Trueing is the next step just get some laps in getting used to the speed these things carry through corners and keep rotating tyres, slowly you true them down a bit. After a couple of meetings get Trueing and be amazed what goes round a corner!!!

tom00182 · #31 20-09-2015

Thanks for all your help. Raced the car for the first time this morning and stuck it 6th in the A final (7 cars per final) out of the 14 drivers. Really awesome car to drive. Unfortunately the motor moved in the final and stripped the spur. Is the motor moving a common problem because that would be the third time it has moved in the short time I have had it. I am doing the motor screws up as tight as I can.

mark christopher · #32 21-09-2015

Which car is it?

tom00182 · #33 21-09-2015

X12 15 my dad wanted the associated

Chequered Flag Racing · #34 21-09-2015

Quote:

Originally Posted by tom00182

Is the motor moving a common problem because that would be the third time it has moved in the short time I have had it. I am doing the motor screws up as tight as I can.

Only in a big shunt or if not tightened up correctly.

Are you using washers behind the motor mounting screws?

tom00182 · #35 21-09-2015

I put some shims in yesterday which reduced the problem but they were only small

SlowOne · #36 21-09-2015

To stop a motor from moving in a shunt...

Make sure that you have steel washers under the head of the motor screws, the larger the better. On some cars you can't use one any bigger than the head on the lower screw as the lower pod plate sticks out beyond the motor mount and a large washer will foul it.

Find yourself some used 600 grit Wet 'n Dry paper. If it's new then get something like an old diff washer and rub it across the paper 30 or so times to knock the edge off the grit. Alternative is 1000 grit, but since one never uses that for anything else its a bit of an expense!

The problem is that the surface of the anodising has a low coefficient of friction. Take the wet 'n dry paper and very (VERY!) gently rub it across the motor plate where the motor fits against the plate (the inside of the motor plate) so that you take the shine off the anodising, but don't take the anodising off. It should look like a matt finish now. This greatly raises the coefficient of friction making it harder for the things to slip.

Now do the same on the motor. Again, take the shine off the anodising, not the anodising off the motor plate.

You can be a bit more aggressive than you think once you get the hang of it. The surfaces should look matt and scuffed, not scratched and damaged. If you do knock the anodising off the odd corner don't panic, it won't do any harm.

Now clean both surfaces with some brake or motor cleaner and leave to 'dry'. Re-assemble as before. Do not keep tightening the screws to avoid the problem, you will damage the threads in the motor plate to the point where they won't hold the motor in properly, or will strip.

The combination of the steel washers and the scuffed surfaces should prevent the problem happening again. As, of course, will driving better and not hitting the barriers in the first place!!

I hope that does help.

PS - take those shims out! They will not fully support the motor which makes it more likely you will bend a motor plate in a shunt. Motor to plate only please!