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PollyMobiles Rebuild
- Thread starter pollyp
- Start date
OP
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pollyp
Club Member
meh live n learn
OP
OP
pollyp
Club Member
ah even cheaper at screwfix plus its local, m6x16mm 10pk £1.11 each
3x = £3.33 and I'll be grinding them shorter anyway
http://www.screwfix.com/p/set-screws-a2-stainless-steel-m6-x-16mm-pack-of-10/69452
3x = £3.33 and I'll be grinding them shorter anyway
http://www.screwfix.com/p/set-screws-a2-stainless-steel-m6-x-16mm-pack-of-10/69452
OP
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pollyp
Club Member
indeed I do, needs tacking together with precision using the stick weld and Alu block. oh joy.
pretty certain I'll be missing the trackday
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pollyp
Club Member
Madman or genius?? Hats off to you pollyp for your unrelenting development and sheer hard work
abit of both. just doing my r&d thing
thx for the compliment
OP
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pollyp
Club Member
was taping it up but i think i should just get on with tacking it together cos the tape ain't gonna hold the joints accurately anyway.
just notice i have to be absolutely spot on with the welder on every joint within 1mm so this'll test my sight, skills and patience tomorrow
just notice i have to be absolutely spot on with the welder on every joint within 1mm so this'll test my sight, skills and patience tomorrow
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OP
OP
pollyp
Club Member
before i weld the pieces together I first do some test welds on some scrap sheets.
clamp the sheets onto the Alu L-corner to keep it square and reduce blow-through.
preheat the stick tip by sticking on the scrap metal afew times to make the strike easier and progressive.
just tacking it with a brief touch for bout 0.2s and the result is surprisingly very good, nice penetration, zero blowthrough, zero distortion and quite strong
commence making the front tray. notice the work piece and the scrap sheet are both clamped to the ground lead so that i could quickly preheat the tip on the scrap then begin joining
tacking it is sooo easy and its such a satisfying pleasure that its going so well. needs few final tweaks to fit onto the engine perfectly
begin making the trickier rear tray/scraper
cyl1, 2 & 3 tray tacked. I've intentionally left out the back plate so i can test fit the scraper tray on the block and visually triple check the scraper definately clears the crank before tacking the back plates on
joining the trays together
continue tomorrow.
the weldings going better than i thought
clamp the sheets onto the Alu L-corner to keep it square and reduce blow-through.
preheat the stick tip by sticking on the scrap metal afew times to make the strike easier and progressive.
just tacking it with a brief touch for bout 0.2s and the result is surprisingly very good, nice penetration, zero blowthrough, zero distortion and quite strong
commence making the front tray. notice the work piece and the scrap sheet are both clamped to the ground lead so that i could quickly preheat the tip on the scrap then begin joining
tacking it is sooo easy and its such a satisfying pleasure that its going so well. needs few final tweaks to fit onto the engine perfectly
begin making the trickier rear tray/scraper
cyl1, 2 & 3 tray tacked. I've intentionally left out the back plate so i can test fit the scraper tray on the block and visually triple check the scraper definately clears the crank before tacking the back plates on
joining the trays together
continue tomorrow.
the weldings going better than i thought
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OP
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pollyp
Club Member
Bloody impressive stick welding!
aye, all that detailed preparation getting the edges dead straight n exact and using the L-jig on square corners seemed to work out gr8 and made the welding go so much smoother. I only had one chance to weld the pieces and tis going well so far
OP
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pollyp
Club Member
mean the welding s'lag u chip off? just sweep it up n bin
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pollyp
Club Member
na just normal electrode +ve.
found weld quality was more bout getting ampage and technique right
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pollyp
Club Member
joined trays 1-4 together
little jiggery to get it sitting flat against the cage
the distance between each cyl tray is a fraction mm short, particularly cyl4 is too far in but will fix with abit of hammering n cutting
cyl2-3 just within spec
gap from cyl1 counterweight
started joining cyl4 and oops that minor fraction mm offset made the corner foul the counterweight
abit of bending n hammering sorted that
joined the lower plates and end flaps
now with the minor offset between each tray, it definately has to be anchored n secured onto the girdle exactly precisely, can't be 1/2mm off.
so next bit is to drill some precise locating holes and bolt it onto the girdle before i cap the backend
little jiggery to get it sitting flat against the cage
the distance between each cyl tray is a fraction mm short, particularly cyl4 is too far in but will fix with abit of hammering n cutting
cyl2-3 just within spec
gap from cyl1 counterweight
started joining cyl4 and oops that minor fraction mm offset made the corner foul the counterweight
abit of bending n hammering sorted that
joined the lower plates and end flaps
now with the minor offset between each tray, it definately has to be anchored n secured onto the girdle exactly precisely, can't be 1/2mm off.
so next bit is to drill some precise locating holes and bolt it onto the girdle before i cap the backend
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OP
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pollyp
Club Member
It's taken me all night to get to this point.
-marking and centre punching and drilling the 2mm holes on the tray.
-position the tray on the engine.
-mark the holes location on the girdle cage with the 2mm bit through the predrilled tray holes.
-take off the cage.
-spirit level the drill press.
-prop the girdle on the drill base with some wood till the tapered surface i'm drilling is level and square to the drill.
-drill through starting with a small 2mm bit to maintain accuracy then gradually enlarge.
had a brief scare here cos i was drilling the first hole and when i thought the drillbit was abit blunt i pressed abit harder, heard the bit stutter and then ping, it snapped inside the hole worst nightmare. but to my luck it happened just as it was about to come out the other end (the girdle main bolt holes) so got a small nail and hammered the broken drill bit through and out the other end n carried on with a bigger drill. note to self, NEVER force those small drilll bits or they will snap and cause a major issue.
-what i first did was try to drill the holes on the girdle cage and tray seperately and hope they match, which didn't work.
-so what i did and should've done was clamp the tray into position on the girdle and drill & tap all the holes in one go.
tray bolted on
bolts angled square to the surface
will need trimming shorter
-marking and centre punching and drilling the 2mm holes on the tray.
-position the tray on the engine.
-mark the holes location on the girdle cage with the 2mm bit through the predrilled tray holes.
-take off the cage.
-spirit level the drill press.
-prop the girdle on the drill base with some wood till the tapered surface i'm drilling is level and square to the drill.
-drill through starting with a small 2mm bit to maintain accuracy then gradually enlarge.
had a brief scare here cos i was drilling the first hole and when i thought the drillbit was abit blunt i pressed abit harder, heard the bit stutter and then ping, it snapped inside the hole
worst nightmare. but to my luck it happened just as it was about to come out the other end (the girdle main bolt holes) so got a small nail and hammered the broken drill bit through and out the other end n carried on with a bigger drill. note to self, NEVER force those small drilll bits or they will snap and cause a major issue.-what i first did was try to drill the holes on the girdle cage and tray seperately and hope they match, which didn't work.
-so what i did and should've done was clamp the tray into position on the girdle and drill & tap all the holes in one go.
tray bolted on
bolts angled square to the surface
will need trimming shorter
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OP
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pollyp
Club Member
didn't get much done yesterday as i wanted cos I was kinda outa steam so took a break and had other work to do.
but what i did do in the morning was finish securing the rear tray to the girdle. rather than try cut the new bolts I just swapped for some shorter bolts till it clears the main journal bolt holes.
the end plates bent/hammered in shape and bolted down
the backplates welded on
next is fit the front tray and make the 4 trapdoors
but what i did do in the morning was finish securing the rear tray to the girdle. rather than try cut the new bolts I just swapped for some shorter bolts till it clears the main journal bolt holes.
the end plates bent/hammered in shape and bolted down
the backplates welded on
next is fit the front tray and make the 4 trapdoors
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OP
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pollyp
Club Member
tday is much cooler n bareable.
i went to b&q to grab a £25 bench grinder cos i always wanted to sharpen my drill bits and tis my first one. quality's abit shoddy (wheels not perfectly true) but meh it kinda works. grinded the first few bits and they drill good as new. wow how did I ever get by using my precious drill bits all these yrs without a bench grinder?
anyway continued working on the front tray and its now bolted on
fits like a glove inside the sump
next making the 4 lower gates and then the oil control baffle will be complete
i went to b&q to grab a £25 bench grinder cos i always wanted to sharpen my drill bits and tis my first one. quality's abit shoddy (wheels not perfectly true) but meh it kinda works. grinded the first few bits and they drill good as new. wow how did I ever get by using my precious drill bits all these yrs without a bench grinder?
anyway continued working on the front tray and its now bolted on
fits like a glove inside the sump
next making the 4 lower gates and then the oil control baffle will be complete
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frank
Club Member
did,nt you buy a wheel dresser paul ? i use a dressing stone personally
OP
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pollyp
Club Member
not that i know of frank, first time i've heard of such tool. googled it and oh so thats how u resurface a grinding wheel. will keep in mind.
the side washers that hold the grinder wheel straight are cheap stamp outs so tisn't absolute flat and the shaft has areas of undercuts so the washers barely sit concentric on the shaft. i'll be replacing with large flat washers but the wheel offset is prob 0.5mm wobble, not bad once upto speed.
the side washers that hold the grinder wheel straight are cheap stamp outs so tisn't absolute flat and the shaft has areas of undercuts so the washers barely sit concentric on the shaft. i'll be replacing with large flat washers but the wheel offset is prob 0.5mm wobble, not bad once upto speed.
OP
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pollyp
Club Member
i thought the previous split door design of the windage gates seemed to restrict the outflow cos naturally the oil being flung out the crank will mostly wanna flow out the bottom hole at a tragectory down and backwards due to the rotation of the crank.
so to provide the easiest route i redesigned the gates to open facing backwards like the louvres on a normal windage tray.
one less moving hinge per cyl will improve reliability of the gate and the larger surface area will allow the sloshing oil to push the gate closed more effectively and improve its responsiveness against reverse surge during cornering.
the opening angle is limited to 10deg to prevent it fouling the higher LH of the sump
now lets make it
so to provide the easiest route i redesigned the gates to open facing backwards like the louvres on a normal windage tray.
one less moving hinge per cyl will improve reliability of the gate and the larger surface area will allow the sloshing oil to push the gate closed more effectively and improve its responsiveness against reverse surge during cornering.
the opening angle is limited to 10deg to prevent it fouling the higher LH of the sump
now lets make it
OP
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pollyp
Club Member
ah this engines gonna p*ss me off.
rang machinist and he took afew thou off the bores but the ring end gaps and piston to bore gaps still too tight so will need further honing.
turns out the remachined spare block was abit too tight within JE's recommended min piston-bore gap so there's signs of where it scuffed. but he says if he hones too much it could start to rattle.
i'm quickly running outa time here and said i need it very soon, early next week the latest.
I definately won't make oulton park on 14th and I may have to prolong my temporary insurance cover to drive my moms car abit longer.
schedule not looking good
rang machinist and he took afew thou off the bores but the ring end gaps and piston to bore gaps still too tight so will need further honing.
turns out the remachined spare block was abit too tight within JE's recommended min piston-bore gap so there's signs of where it scuffed. but he says if he hones too much it could start to rattle.
i'm quickly running outa time here and said i need it very soon, early next week the latest.
I definately won't make oulton park on 14th and I may have to prolong my temporary insurance cover to drive my moms car abit longer.
schedule not looking good
OP
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pollyp
Club Member
all 4 brackets cut
was gonna tack some 1mm weld rod on the edge to form the hinge but was very tricky. either the weld didn't join or the weld simply burnt the rod off.
could've spend all night recutting another alternative but instead i tried wrapping the tab around the rod like this and re-trim the clearances
the pivot hole will have to be repositioned
so it slots like this. tbh there's not alot of metal round where the hinge pivots so may wear through and i would've either riveted a miniature piano hinge or remodelled/recut it all instead but meh, it'll do and cba with further work and buying the special bits and more dremel wheels etc
the bolt holes will be interfering with the ones on the side so they'll need shortening
was gonna tack some 1mm weld rod on the edge to form the hinge but was very tricky. either the weld didn't join or the weld simply burnt the rod off.
could've spend all night recutting another alternative but instead i tried wrapping the tab around the rod like this and re-trim the clearances
the pivot hole will have to be repositioned
so it slots like this. tbh there's not alot of metal round where the hinge pivots so may wear through and i would've either riveted a miniature piano hinge or remodelled/recut it all instead but meh, it'll do and cba with further work and buying the special bits and more dremel wheels etc
the bolt holes will be interfering with the ones on the side so they'll need shortening
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OP
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pollyp
Club Member
hinge brackets are bolted on and the girdle cage is secured onto the sump
filled with 3.5L water, the opening seems to flow well enough.
tilted the sump around and it doesn't quite worked as well as i hoped
it's mainly cyl4 that gets all the sloshing and the gate does close but doesn't close fast enough due to weight and the fact that the fluid is actually surging 'across' the thin cross section of the gate opening rather than 'up' against the face of the gate hence no enough pressure to force it closed.
gates # 1, 2 and 3 never closes
here i filled with more water and moved it laterally to simulate sudden high G turns and the rappid gush of water has more effect on closing the gate but some fluid still gets past initially till the gate closes.
gate # 2 & 4 appears to close but gate #1 & 3 still never closes
in comparison here's a stock girdle cage with no windage tray and the water simply pours into the cage with ease
so maybe the windage tray does shield the crank from some oil sloshing but I'm beginning to doubt the effectiveness of the swinging gates.
I was gonna try weld some 45deg vanes under each gate door to help force the door up when the fluid hits it but tbh there's no space under cyl4 and I've lost the will to develop the gates further tbh
i think what i should try instead are some static back-facing louvres like on all windage trays.
alot more reliable and cyl 1-3 don't get any sloshing anyway.
another day cos i'm getting a headache :/
filled with 3.5L water, the opening seems to flow well enough.
tilted the sump around and it doesn't quite worked as well as i hoped
it's mainly cyl4 that gets all the sloshing and the gate does close but doesn't close fast enough due to weight and the fact that the fluid is actually surging 'across' the thin cross section of the gate opening rather than 'up' against the face of the gate hence no enough pressure to force it closed.
gates # 1, 2 and 3 never closes
here i filled with more water and moved it laterally to simulate sudden high G turns and the rappid gush of water has more effect on closing the gate but some fluid still gets past initially till the gate closes.
gate # 2 & 4 appears to close but gate #1 & 3 still never closes
in comparison here's a stock girdle cage with no windage tray and the water simply pours into the cage with ease
so maybe the windage tray does shield the crank from some oil sloshing but I'm beginning to doubt the effectiveness of the swinging gates.
I was gonna try weld some 45deg vanes under each gate door to help force the door up when the fluid hits it but tbh there's no space under cyl4 and I've lost the will to develop the gates further tbh
i think what i should try instead are some static back-facing louvres like on all windage trays.
alot more reliable and cyl 1-3 don't get any sloshing anyway.
another day cos i'm getting a headache :/
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OP
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pollyp
Club Member
aye the thicker oil has more mass behind it but from this simple test I can't be sure if the gate is configured to work correctly.
where i was chucking it suddenly sideways may be abit extreme but it could happen at say a fast slalom course?
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pollyp
Club Member
Is there a benefit of one vs the other ?
If its close i'd go the easier route and go with the louvres.
nice amount of R&D though...been watching this secretly haha.
well I'll soon find out if one works better than the other once i make the louvre design.
thats the point of all this trail & error testing is to design the part theoretically, make a prototype and test if it supports the theory. if not, then back to the drawing board with the results learnt and re-evaluate.
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pollyp
Club Member
here's the louvre design. calculated each side opening with the same area.
i find personally i tend to design things way too complicated at first before I eventually find the best one is the simplest
as they say 'keep it simple stupid'
cross section of the louvre. in theory the oil sloshing over will at first be more likely to travel the path of least resistance, past the opening at the side of the cage and up the side of the sump before the pressure then finds its way into the louvre
i find personally i tend to design things way too complicated at first before I eventually find the best one is the simplest
as they say 'keep it simple stupid'
cross section of the louvre. in theory the oil sloshing over will at first be more likely to travel the path of least resistance, past the opening at the side of the cage and up the side of the sump before the pressure then finds its way into the louvre
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OP
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pollyp
Club Member
new windage tray
fitted to the girdle
using the crank bolts on some scrap wood to secure the tray
view of the side opening gaps
can see the tray completely shields the underside from the oil splash
too dark to test the sploshing so to test if the openings are big enough to drain the oil, I ran a tap over it fully open n see if it doesn't build up.
and the opening gaps on both sides seem to drain the water away nicely
tomorrow will see if it'll finally resolve the sloshing issue
fitted to the girdle
using the crank bolts on some scrap wood to secure the tray
view of the side opening gaps
can see the tray completely shields the underside from the oil splash
too dark to test the sploshing so to test if the openings are big enough to drain the oil, I ran a tap over it fully open n see if it doesn't build up.
and the opening gaps on both sides seem to drain the water away nicely
tomorrow will see if it'll finally resolve the sloshing issue
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OP
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pollyp
Club Member
got good & bad news from machinist.
good is the engines almost done for prob tomorrow and he got the clearances as good as he can.
bad is the locating notch on the new lower main bearing shells don't match the girdle cage so I'd either have to order another set of the correct oversize shells or reuse the original lower shells which are in ok state, decided to reuse em.
another bad bad news when i asked is that girdle cages cannot be swapped between engines else it'll jam cos the girdle & block are uniquely align bored together.
which means all that friggin grinding and drilling etc for the windage tray was all wasted for nothing and I'll have to do it all over again on the new girdle cage and can't be certain that all the hole'll be all proper align now ARGHHHHH
more friggin work and time delays. not good
good is the engines almost done for prob tomorrow and he got the clearances as good as he can.
bad is the locating notch on the new lower main bearing shells don't match the girdle cage so I'd either have to order another set of the correct oversize shells or reuse the original lower shells which are in ok state, decided to reuse em.
another bad bad news when i asked is that girdle cages cannot be swapped between engines else it'll jam cos the girdle & block are uniquely align bored together.
which means all that friggin grinding and drilling etc for the windage tray was all wasted for nothing and I'll have to do it all over again on the new girdle cage and can't be certain that all the hole'll be all proper align now
ARGHHHHHmore friggin work and time delays. not good
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pollyp
Club Member
filled the sump with water and tested the new tray against gradual cornering by tilting and it does an ok job.
The slow moving water builds up higher and the pressure from the long sloshing would eventually find its way into the side openings and creep into the chamber but at least it slows it down
when i test it against sudden lateral nudges it works much more effectively as the fast moving fluid would rather flow easily straight past the opening and up the sump walls than into the perpendicular tunnel into the crank, and keeping the crank area drier
The slow moving water builds up higher and the pressure from the long sloshing would eventually find its way into the side openings and creep into the chamber but at least it slows it down
when i test it against sudden lateral nudges it works much more effectively as the fast moving fluid would rather flow easily straight past the opening and up the sump walls than into the perpendicular tunnel into the crank, and keeping the crank area drier
OP
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pollyp
Club Member
oh ffs it just dawned on me that the whole point of getting the crank grinded and fitting the oversized shells was to replace the pitted #1 lower main shell, and now that i told the guy to reuse the old lower shells cos the new ones didn't fit, made the whole exercise completely pointless and a waste of money
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pollyp
Club Member
oh SH#!
MAJOR problem with the new engine.
the crank is grinded oversize so needs O/S bearing shells.
machinist fitted the new o/s upper shells but can't fit the new lower o/s shells cos if the incorrect tabs.
he refitted the old STD lower shells cos he thought they were the same. obviously not after we just discussed. o/s and STD cannot be mixed.
so we need o/s upper & lower shells.
i asked if they prev managed to locate the proper o/s shells for this engine and no they didn't
oh OHH so we don't have any proper shells which puts this engine DEAD in the water
crap
it's just this mismatch bearing shell tab that's the issue.
i asked if maybe the tabs on the new o/s lower shells could be modified to fit? he's gonna have a look and get back to me.
at the mo I'm thinking its either we bend a new tab on the new o/s bearing shells = risky
or maybe we could machine a new slot on the girdle cage to accept the new shells?
MAJOR problem with the new engine.
the crank is grinded oversize so needs O/S bearing shells.
machinist fitted the new o/s upper shells but can't fit the new lower o/s shells cos if the incorrect tabs.
he refitted the old STD lower shells cos he thought they were the same. obviously not after we just discussed. o/s and STD cannot be mixed.
so we need o/s upper & lower shells.
i asked if they prev managed to locate the proper o/s shells for this engine and no they didn't
oh OHH so we don't have any proper shells which puts this engine DEAD in the water
crap
it's just this mismatch bearing shell tab that's the issue.
i asked if maybe the tabs on the new o/s lower shells could be modified to fit? he's gonna have a look and get back to me.
at the mo I'm thinking its either we bend a new tab on the new o/s bearing shells = risky
or maybe we could machine a new slot on the girdle cage to accept the new shells?
