Esprit's sexseige (newschoolspaceship)

[Unclejake]

Who have you selected for the engine work?

[Esprit]

Who have you selected for the engine work?

Was thinking about doing it myself (well the assembly / set-up work anyway) Don't think there'll be any machining necessary other than perhaps a little porting on the head and perhaps some reaming of the new colisbro valve guides when they're in.

Why? you have someone in mind?

[Unclejake]

I don't have anyone in mind - just curious as to who you trusted wherever you live (I assume Auckland).

I would start talking with guys like Lyn Rogers and Roger(?) from Lotus Cars in Waiuku I guess

[Esprit]

I don't have anyone in mind - just curious as to who you trusted wherever you live (I assume Auckland).

I would start talking with guys like Lyn Rogers and Roger(?) from Lotus Cars in Waiuku I guess

Lynn Rogers is in line to do my porting work I think. Was going to get Ken at Lotus NZ to do it but he's never built a VHPD-K bottom end before and given there's only 3 of these engines in NZ I'm doubting anyone has. Roger at LCNZ doesn't do any of the mechanical stuff, that's all contracted to Allports these days who have pretty much zero experience with the Rover K-engined cars.

Hence why I'm doing it myself... there's a wealth of info out there on the net through some of the UK clubs I'm involved with (like SELOC).. and I'll probably end up buying all my parts through someone like Dave Andrews (DVAPower) or QED on the condition I get some free helpline advice on how it should all go together

Engine building ain't brain surgery, it just needs care and attention, something I'm more likely to lavish on it than someone who's trying to turn it around for a profit.

[Guest vvega]

have you heard of exfoliation corosion on alloy ?

i think you will find coating the floor with por will just hide it

if it was a aircraft you woudl have required to cut the coroded section out and rivit in a new section

also ...look up alodine

its a process i would advise you do to any alloy you have scuffed/polished and taken the alclad coating off

just tring to help mate

[Esprit]

Exfoliation corrosion is typically only prevalent in high strength aluminium alloys and the floors in the Lotus don't fall into that category. They're just a standard 5000 series alloy and aren't structural, they're pretty much just there to stop you doing a flintstones impression

Crevice corrosion is also a galvanic reaction and usually needs some dissimilar metal or moisture contact to initiate and propagate it.... I don't have any dissimilar metals in galvanic contact with the floor (it's isolated by the glue that's used to bond the floors in) and moisture contact has been banished by the POR15 (stagnant moisture trapped in a low-oxygen environment was what caused the existing crevice corrosion in the first place).

Thanks for the tip though, always nice to have someone else cast a critical eye over the work

[fishtailfred]

Was thinking about doing it myself

Good man.

Engine building ain't brain surgery, it just needs care and attention, something I'm more likely to lavish on it than someone who's trying to turn it around for a profit.

Absolutely!!

[Guest vvega]

Exfoliation corrosion is typically only prevalent in high strength aluminium alloys and the floors in the Lotus don't fall into that category. They're just a standard 5000 series alloy and aren't structural, they're pretty much just there to stop you doing a flintstones impression

Crevice corrosion is also a galvanic reaction and usually needs some dissimilar metal or moisture contact to initiate and propagate it.... I don't have any dissimilar metals in galvanic contact with the floor (it's isolated by the glue that's used to bond the floors in) and moisture contact has been banished by the POR15 (stagnant moisture trapped in a low-oxygen environment was what caused the existing crevice corrosion in the first place).

Thanks for the tip though, always nice to have someone else cast a critical eye over the work

Exfoliation Corrosion. Exfoliation corrosion is a special form of intergranular corrosion which occurs when the grains are flattened by heavy deformation during hot or cold rolling, and where no recrystallization has occurred. Exfoliation is characteristic for the 2000 (Al-Cu), 5000 (Al-Mg), and 7000 (Al-Zn) series alloys which have grain boundary precipitation or depleted grain boundary regions.

Intergranular corrosion initiates often at the sites of crevice corrosion or pitting corrosion.

Intergranular corrosion can occur by either (a) the dissolution of a more active grain boundary precipitate; or ( the dissolution of a depleted matrix around a more noble grain boundary precipitate

the reason the requirement in aircraft is removal is once you have pits there is nothign you can do to stop intergranular from spreading internally in the material

and been that its is a chemical reaction corosion starvation from water or air will not slow or inpeed the corosion unless the section was removed

lastly alodine gives you far more corosion protection than por 15 would

we applied to have por15 used as a coating on aluimuim aircraft parts and it was rejected becuase it was considered unsuitable on aluminuim because there was no adheasion though the oxide.......alloy paint requires a etch

just came across your post about POR-15. I tried some last winter on my polished front forks and other various motorcycle parts. spent days and days polishing and then applied the POR-15. Was not happy at all with the finished product. i contacted the company and they told me to thin it with Xylene, so I removed all the old POR-15, which took hours and then thinned the POR and did it all over again. SAME results!##%$%^ Threw the S**t away. Save your money.

ben

like you said at the end of the day its only a floorpan

I was just sharing some of my experance working with aircraft and alloy products

hope that helps

and yeah building a engine isnt hard but you need to know the process or you can forget somthing you didnt even know you had to do

if youve rebuilt a few engines and had no issues then id say go for it if you havent get a good book from a reconised author and go for it

i woudl also stay well away from internet advice when building engines...there is a lot of false info and web bulshit on there

though i have no doubt you already know this

[Esprit]

The problem most people have had with POR15 is on polished metal parts and poor adhesion (like your motorcycle example above). POR15 likes seasoned material, and hence my floopans were prepped with both mechanical abrasion and an acid etch (as you recommended, and as specified by PPC themselves).

Bear in mind that I mechanically removed all visible signs of remaining corrosion in the pits as well as applying the coating so it should be fine. In the end it comes down to the fact that the 5000 series alloy used in the floorpans isn't particularly prone to intergranular corrosion. The only fault here is that of Lotus who cocked up and failed to recognise their original floor covering and their method of attachment wasn't suitable for what they had planned. The matierial was originally protected by an anodised layer, which wasn't resistant to this particular type of environmental attack.. which was a stupid error on their part.

In any case, we'll see in a few years time. For now, the POR15 seems to have adhered to the metal VERY well (ain't no way it's coming off) and it's non-porous so it should keep all moisture and oxygen away from the metal, meaning that existing corrosion should have no reason to go any further so long as the coating adhesion isn't compromised.

[Guest vvega]

its a interesting subject

5000 series allooys are considered marine alloys and can be submersed in salt water with almost no adverce effects

your right they are extremely resistant to corosion

yet put a matt on them and they fuck out...i dunno if id go with lotus's reasoning

[Esprit]

its a interesting subject

5000 series allooys are considered marine alloys and can be submersed in salt water with almost no adverce effects

your right they are extremely resistant to corosion

yet put a matt on them and they fuck out...i dunno if id go with lotus's reasoning

Yeah well 5000 series alloys also anodise extremely well, which is one of the pluses with them. The issue would have happened with most alloys really, the problem was that water could get beneath them and stagnate. Due to the sealed nature there, you got crevice corrosion which loves those conditions.... it was less the moisture and more the trapped nature of stagnant moisture that leads to the crevice corrosion. It's a very interesting and unique method of corrosion really, one that Lotus obviously didn't think through.

Ironically, where the mats were adhered to the floors never corroded, so if they'd adhered the whole mat down rather than just a strip around the edges, the problem would have never existed! It's an odd one for sure.

[Testament]

you just been brushing that por15 on? looks like its comes you pretty good from the photos? any brush marks etc irl?

[Esprit]

you just been brushing that por15 on? looks like its comes you pretty good from the photos? any brush marks etc irl?

The shock mounts have just had it brushed on... with a cheap brush... using POR15 that's been opened too many times and used in too cold conditions (so it's thick like treacle)... no brush marks in the gloss but a few small ones in the metallic flake in the silver... certainly good enough for suspension components and stuff.. the paint actually levels really well if you use it according to instructions and don't gob it on too thick in one coat.

[thminiman]

in semi unrelatedness, i painted my trailer with brush and por15, it says to put it on quite thick comparedto most paints, and like you say, it drys mean, barely left any brush marks on trailer except where i obviously put it on too thin.

and yea, buy cheap brushes and dont even bother trying to clean them, just biff it out and use the next one. lol this comes from the experience of me trying to clean one with black paint, then realising the meths/turps everything else wasnt diluting it, and i was using my bare hands

i had black/blackish hands for about 2 weeks

[Esprit]

in semi unrelatedness, i painted my trailer with brush and por15, it says to put it on quite thick comparedto most paints, and like you say, it drys mean, barely left any brush marks on trailer except where i obviously put it on too thin.

and yea, buy cheap brushes and dont even bother trying to clean them, just biff it out and use the next one. lol this comes from the experience of me trying to clean one with black paint, then realising the meths/turps everything else wasnt diluting it, and i was using my bare hands

i had black/blackish hands for about 2 weeks

Yeah it's evil sh*t on your hands... I've still got silver fingernails now

It cleans up all right in general purpose thinners although you have to make sure the brush is thoroughly rinsed after and then dried before it's useable again. But yeah, best to buy cheap brushes and chuck-em

[Guest vvega]

mek disolves it

but takes your brain with it

[Esprit]

mek disolves it

but takes your brain with it

In my experience, there's very few things that MEK won't dissolve

Coating up my wishbones and uprights today, will post pics/update in the build thread tomorrow when they're coated and dry enough to handle

[Truenotch]

Haha I like the freshly painted suspension parts dangling in the office!

[Esprit]

Workshop was too cold for the paint to cure, so they came upstairs to sit under the heat pump for a couple hours

[Guest vvega]

i only just realised ... your george

work for can-do ?? with winston...

am i right