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PollyMobiles Rebuild

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pollyp

pollyp

Club Member
tried to machine this large dia long pipe on the lathe but will have to wait another day cos I'll need to buy an overhang support to stop it popping off the chuck

IMAG5233.jpg
 
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pollyp

pollyp

Club Member
the other day during cold start I noticed the battery light took afew sec to extinguish (slight corrosion on the alternator slip rings?)
so took it out to check

IMAG5549.jpg


little rust on the slip rings

IMAG5550.jpg


getting abit worn

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wirebrushed it all clean. still some meat and spring-ness left on the brushes but it's getting near to the end

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cleaned & reinstalled

IMAG5554.jpg
 
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pollyp

pollyp

Club Member
decided to wire some interior light back in so I can see the IGN barrel at night and keep the cool auto dimming.
found the top of the windscreen frame is the perfect place for sticking the LED strip

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wired a mini switch and there's a convenient hole for it here

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so now the LED can shine over the whole cockpit

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the chassis frame & visors reducing glare

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interior nicely lit up at night

IMAG5568.jpg
 

Low Rider

Poindexter
Founding Member
Moderator
Club Member
erm has JAE moved venue again back down to the midlands at peterborough? early morning for me
Ah, so they've gone back to a former venue (East of England Showground).

That may very well change my opinion on attending...
 
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pollyp

pollyp

Club Member
was curious if I could use the coilover top pillowball as the bottom balljoint for extending the roll centre. I estimate the bearing's bout 35mm diameter

IMAG5572.jpg


looking under the ball joint, the hole seems to be the same 35mm so in theory I might be able to press a BC pillowball bearing straight into the standard arm with no major structural mod (retaining the strength) and just afew minor mods to keep it retained

IMAG5575.jpg


looking at stiffening the lower brace with extra X-beams, if I weld a tube from one end of the lower brace to the diagonal swaybar mount, the middle engine beam is in the way and needs cutting/weakening

IMAG5576.jpg


if it goes from the swaybar mounts to the middle of the lower brace where it's already anchored to the middle engine beam, it may foul with the gear selector in 5th/reverse

IMAG5577.jpg


imo the lower brace is already firmly anchored to the middle engine beam so the diagonal beams ain't high priority
 
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pollyp

pollyp

Club Member
work in prog, just measured the rear seat belt bolt holes and modelled the rear X-brace so the forces travel along the beams and directly towards the mount.
involves some complicated notch angles so this is handy for planning the cuts

rear X brace 1.jpg
 

SuperUno

Buy & Sell Member
If you are that worried about shell flex, then get a proper cage in it. You will be amazed how much flex is going on that you don't notice now. Plus it will make the car safer...
 
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pollyp

pollyp

Club Member
If you are that worried about shell flex, then get a proper cage in it. You will be amazed how much flex is going on that you don't notice now. Plus it will make the car safer...
aye the back of the chassis is pretty much as floppy as chocolate pudding sponge but my aim is to make a removable bolt-on frame that helps stiffen that rear structure abit only for trackdays and then during normal use I just pop it off to retain the interior space and easy to store away.

although a fully commited race spec cage offers a very stiff platform and a safety cell (with appropriate safety gear), there's afew reasons why it's not suitable for me at the moment:
-cost: I imagine the cost of materials, design, bending, welding a surrounding cage will run into high hundreds to purchase, which I can afford.
-space: all that thick tubing will be intrusive, obstruct my A-pillar gauges, most likely have to cut the dash to route the pipe near the pillars, lose rear seats & versatility and is pretty permanant.
-safety gear: the safety cage is fine if this was only used for motorsport where I'd wear helmets etc but it's a daily car. meaning I simply wear normal clothes without helmet most of the time and the potential of smashing my body/head against a nearby solid cage if I crashed ain't worth thinking.
-extra insurance premium: the car is already difficult & expensive enough to insure for public use and I can't imagine many will accept this car with a cage nor would it be economically viable.
 
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pollyp

pollyp

Club Member
ah shyte bad news, think I broke my 3D printer :(
the special control board is a 5Dprint D8 board using an Atmel AT90USB1286 chip and was originally shipped with a unique 5Dprint firmware which is difficult to customise/edit.

just recently I managed to figure how to flash "Marlin" (a very commonly used 3D printing firmware) onto this board and allowed be full control over every parameter.
was going well as I was tweaking the parameter numbers & reflashed the chip
But then my PC froze while mid-flashing the chip, the firmware file was lost and now the control board is really buggered, the USB port ain't detected at all, I fear I've bricked it and I can't find replacements anymore :(:oops:
crap

trying all sorts to try restore that connection with confusion & no luck.
 
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pollyp

pollyp

Club Member
ok there's hope from talkin to Ralph. since the USB side of the board ain't working, he thinks I just need an atmel AVR ISP programmer device that plugs into the 6-pin ISP port on the control board to directly re-program the missing "bootloader" software onto the chip to restore normal USB functions.

now looking into buying or borrowing an ISP programmer:cool:
or I heard you could even use an arduino as an ISP programmer (I have an un-used arduino DUO)

this is getting very technical
 
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pollyp

pollyp

Club Member
these 34x2.5mm scaffold pipe's arrived. definately beefy enough to stiffen the chassis (overkill compared to my other braces) but wish the walls were thinner than 2.5mm cos it's quite weighty. least it'll shift the 60%/40% weight rearwards. waiting for the 3mm plates before beginning.

IMAG5578.jpg
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gave her a wash

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catchcan captured 50ml after 240miles (210ml / 1000mile)

IMAG5584.jpg
 
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pollyp

pollyp

Club Member
my worksheet and pipe notching templates down on paper

IMAG5585.jpg


while waiting for the 3mm flat steel, I machined the upper & lower chassis mounts. chamfered the end that's gonna be welded to the flat steel to form the bolt hole

IMAG5586.jpg


locates on chassis here

IMAG5587.jpg


before machining the longer mount, I found my mini lathe needs a tool to hold long pieces steady while cutting otherwise its very unstable. another thing to purchase...

or I could just angle grind the chamfers & welds by hand for an OK job so I don't have to buy a £50 tool I'll only use few times. yeah do it by hand
 
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pollyp

pollyp

Club Member
the 3mm steel plate arrived.
figured that to machine a long piece, I just have to make a shaft that fits snug inside the metal pipe and the far end is supported by the tail stock.
machined a kitchen rolling pin down to size, makes a ton of mess. lathe will need a thorough clean afterwards.

IMAG5589.jpg


now I can cut a smooth chamfer on the end for a good weld

IMAG5593.jpg


chamfered pipes and flat plates ready

IMAG5594.jpg


tacked

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welded

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saw the excess off

IMAG5599.jpg


machined it round and drilled the bolt hole

IMAG5600.jpg


lower mount done, 3 more to do

IMAG5601.jpg
 
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pollyp

pollyp

Club Member
machined the long mounts

IMAG5602.jpg


installed

IMAG5605.jpg


notice the angle of the top mount, I guess I'll have to remove the rear seats to use the X-beam.
considering the weight of the rear seats and this X-beam being roughly the same, weight distribution may not change but the structure will be much stiffer and there'll be alot of road noise behind me and boot content won't be hidden. minor bit of sacrifice.

IMAG5607.jpg


to visualize & further refine all the tubular angles, I attached some strings

IMAG5611.jpg


with the mounts fitted, I can measure the exact pipe notch angle required and recalculate the 3D model

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IMAG5610.jpg


the upper mount actually points slightly offset to the diagonal tubes rather than being in-line, so I'll have to tweak the model to match

IMAG5608.jpg
 
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pollyp

pollyp

Club Member
remeasured all the angles & updated the model

rear X brace 3.jpg


went to screwfix to get a 35mm hole saw (would've preferred a closer fitting 34mm but it's rare and expensive).
made this quick wooden jig on the lathe to clamp the pipe at angle angle. using the saw to cut a hole straight through, it'll now hold the pipe perfectly level with the cutter.

IMAG5614.jpg


clamped a test piece at eg 70deg and begin cutting. the hole saw ain't perfectly straight and the wooden jig is WAYY to flexible. it jammed and broke 1 teeth at one point but I kept at it

IMAG5616.jpg


finally cut through it

IMAG5617.jpg


hey not bad. really need to make a stiffer metal jig before doing the 4 notch cuts cos this wooden flexible jig is abit dangerous.
the much shallower 12deg notch cuts will definately have to be done by hand cos the jig ain't strong enough to handle the extreme overhang needed.

IMAG5618.jpg


filed it smooth

IMAG5622.jpg


ooooh a perfect fit :cool: lovely

IMAG5621.jpg
 
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pollyp

pollyp

Club Member
tday made a much more rigid jig from 6mm L-bar

IMAG5623.jpg


cuts alot more stable without shaking around

IMAG5626.jpg
IMAG5627.jpg
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attempted to see if it can cut the extremely shallow 11deg angle.

the start of a notch cut is always the hardest moment as it shakes, stutters or jams alot if the tube & cutter hangs too far away with less rigidity.
so I begin by mounting the cutter close to the chuck and the pipe close to the jig

IMAG5629.jpg


as it gets past the hard initial start, I extend the cutter and pipe to cut more

IMAG5630.jpg


hacksaw the excess off before cutting deeper

IMAG5633.jpg


the tool can only reach this far so will finish the rest manually.

IMAG5634.jpg


test fit the half finished tube in the car and damn it's a nice precise fit :cool: can't wait to finish the cut and weld it up.
 

SuperUno

Buy & Sell Member
With welding skills like that, you can surely get a job doing that sort of work. Or go it alone like others and produce parts people want to buy for their cars....
 
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pollyp

pollyp

Club Member
finished off the 11deg notch cut. it's a PITA to get two notch angles fitting perfectly, took several hours of repeatedly marking & grinding, back & forth

IMAG5636.jpg


till it fits closely and tack weld it on

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IMAG5640.jpg
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finished the other two pipes. the CAD helped get me close to the angles but there was still alot of fiddly fine tuning cuts to get the fit correct.

IMAG5643.jpg


really messed up one of the angles but afew minutes of grinding got me close enough. lots of 1mm gaps there but I can weld it up fine.

IMAG5644.jpg
 
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pollyp

pollyp

Club Member
received this AVR ISP MK2 programmer I won off ebay for few quid

IMAG5645.jpg


plugged it directly into the control boards ISP port,
opened the device programmer tool in Atmel Studio 6,
it gives you tons of info & programming tick boxs.

downloaded the missing DFU bootloader file and programmed it into the chip memory.

ok, swapped over to the normal USB and try connecting to the board...
omg it worked
hell yeah it's fixed :D:D

back in business of messing around with the printers new firmware :cool:
 
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pollyp

pollyp

Club Member
notched the final top tube

IMAG5646.jpg


tacked

IMAG5647.jpg


welded it up. ain't half bad.

seriously need a less-tinted welding mask cos I really can't see where to weld, so I can't weld continuously and have to pause alot which results in ugly pigeon poop that annoys me :(

my usual preferred method is pulse welding which helps keep the weld looking consistant and controls heat but I found at the machines maximum setting, the molton globs tend to clog up the MIG gun badly and frequently jams it. and then the porous weld bubbles up while cooling due to lack of gas, so had to grind and reweld.

need alot more practice imho

IMAG5650.jpg


to test how much the chassis twists without the brace, I opened all the doors, left the boot open marked with masking tape and jacked up one wheel

IMAG5652.jpg


without bracing, the boot has skewed over by 7mm!

IMAG5653.jpg


bolted the X-brace in, it's a snug fit to get all the bolts lined up

IMAG5659.jpg
IMAG5658.jpg


jacked the corner up and oh gawd, it's barely moved 1mm. :D proof it works

IMAG5655.jpg


comparing weight, all this rear seat & shelf weighs a hefty 22.7kg
while the X-frame only weighs 7.1kg
a reduction of 15.6kg for a stiff chassis! :cool:

IMAG5661.jpg


took it for a drive, dunno if it's a placebo effect but she feels nippier and tighter.
the delay between steering input and feeling the weight shift definately seems sharper and the rear end is feeling abit more loose on these cold old T1R tyres.
road noise is definately louder, exhaust is boomier and stereo is pointless, so will need to wear ear plugs with this layout.

give it some paint tomorrow
 
Loving the removable X brace Paul! I'm quite surprised how much chassis flex there is in a 5 door!

I may have to look into making something like this for my K10 as i'm sure it has less rigid chassis than the K11. You can feel the whole car flex if you go over a speed bump at a funny angle!
 
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pollyp

pollyp

Club Member
Loving the removable X brace Paul! I'm quite surprised how much chassis flex there is in a 5 door!

I may have to look into making something like this for my K10 as i'm sure it has less rigid chassis than the K11. You can feel the whole car flex if you go over a speed bump at a funny angle!
thanks, it's a good conpromise between having a stiffer, lighter, impractical & noisier rear end on trackdays and then easily swapped back to a practical, quieter setup when used daily.

the extra side door openings doesn't seem to cause an issue cos all the door latch lines up fine before/after twisting.
the main cause of the twisting is that big gaping boot hole in the chassis, like a wide open cardboard box. great for boot access but makes the structure so weak, floppy and little squeaky, especially when cornering hard.

the x-frame should help reform that closed cardboard box lid structure, rather than rely on the loose boot lid to hold it
 

frank

Club Member
i know you prefer your mig but have you tried stainless steel arc rods paul ? the welds are 10 x neater than mild steel arc rods
 
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pollyp

pollyp

Club Member
i know you prefer your mig but have you tried stainless steel arc rods paul ? the welds are 10 x neater than mild steel arc rods
although MIG is easier to start, the weld appearance ain't very consistant near it's max setting as the head clogs up.
for consistant good appearance & strength that suits my pulse welding style, I'd prefer the rods.

I tried stainless MIG with Ar/Co2 when I just repaired the exhaust flexipipe and yeah it welds abit better, maybe it's the gas and straight CO is more unstable? cos I had to keep a very short stick-out (which leads to clogging) or else the wire stutters & burns back. and creates alot of spatter. maybe should try nozzle antispatter and ar/co gas?

only stainless rod I last tried was a thick 2.5mm for doing the stainless pipes and that pulse welded nicely too.
lots more to learn
 
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pollyp

pollyp

Club Member
investigating some rusty patches at the rear. have a feeling this RH corner near the seat belt hole that'll be transmitting the X-brace loads to the chassis beam will need repairing soon as the metal could crumble if I stab it any harder

IMAG5663.jpg


cos all that wheel well water just hangs onto this welded edge, making them rust

IMAG5664.jpg
IMAG5666.jpg


damn another rust to patch up near the spare wheel/chassis beam

IMAG5667.jpg
IMAG5669.jpg


and a small patch developing in this common area.
obviously I'll have to repair all of this before any trackday stress.

IMAG5670.jpg


primed the X brace

IMAG5662.jpg


gave it a lick of red

IMAG5671.jpg


hope it doesn't stand out too much lol :D
seem to have this red over grey colour theme going on

IMAG5672.jpg
IMAG5673.jpg
 
notched the final top tube

View attachment 52791

tacked

View attachment 52793

welded it up. ain't half bad.

seriously need a less-tinted welding mask cos I really can't see where to weld, so I can't weld continuously and have to pause alot which results in ugly pigeon poop that annoys me :(

my usual preferred method is pulse welding which helps keep the weld looking consistant and controls heat but I found at the machines maximum setting, the molton globs tend to clog up the MIG gun badly and frequently jams it. and then the porous weld bubbles up while cooling due to lack of gas, so had to grind and reweld.

need alot more practice imho

View attachment 52792

to test how much the chassis twists without the brace, I opened all the doors, left the boot open marked with masking tape and jacked up one wheel

View attachment 52799

without bracing, the boot has skewed over by 7mm!

View attachment 52795

bolted the X-brace in, it's a snug fit to get all the bolts lined up

View attachment 52798 View attachment 52797

jacked the corner up and oh gawd, it's barely moved 1mm. :D proof it works

View attachment 52796

comparing weight, all this rear seat & shelf weighs a hefty 22.7kg
while the X-frame only weighs 7.1kg
a reduction of 15.6kg for a stiff chassis! :cool:

View attachment 52794

took it for a drive, dunno if it's a placebo effect but she feels nippier and tighter.
the delay between steering input and feeling the weight shift definately seems sharper and the rear end is feeling abit more loose on these cold old T1R tyres.
road noise is definately louder, exhaust is boomier and stereo is pointless, so will need to wear ear plugs with this layout.

give it some paint tomorrow
https://www.amazon.co.uk/Parweld-XR916H-Autodarkening-Welding-Helmet/dp/B00GJX0BAQ

Hands down my best purchase. This made my welding a million times better.


Sent from my iPhone using Tapatalk
 
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pollyp

pollyp

Club Member
now that the printers control board is fixed, I figured how to edit & upload the original firmware successfully so now I have full control over all the parameters to fine tune.
made afew improvements while organising the wiring.

controlling the fan speed with the boards PWM always generates an annoying electrical noise so instead I just turned the fan speed 100% to disable the whining PWM and used an external fan controller from my PC

IMAG5676.jpg


reorganised all the wiring to be neater and allow the XYZ parts to move freely

IMAG5677.jpg


fitted a more robust end-stop switch and dampened the vibrating stepper motors from the metal frame with rubber

IMAG5678.jpg


fine tuned all the settings and it's printing really nicely and abit quieter now

IMAG5680.jpg
 
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