BMW V8 dry sump from billet

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AdeV:
That's pretty much the plan, Andy - I've not done the remaining test holes yet, but I expect they'll be off by the same amount. My edge finding was probably not all that accurate when I drilled the holes - or maybe the piece still wasn't quite dead straight on the angle plate, hence the slight misalignment; fortunately, it's not a critical dimension, so I can easily work around it :thumbup:

CrewCab:
Ade ........... what can I say .............. absolutely brilliant work mate :thumbup: no stopping you now feller :clap:

CC :beer:

AdeV:
CC - cheers m8, the only thing slowing me down now is deciding which operations to do next...

So, tonight's not much of an update really. I spent quite a long time trying to work out why the X-axis was really stiff to turn (turned out I had the sump clamped a little too tightly, obviously the table was warping just a smidge, causing it to run stiff, as if the gibs were locked. Things went much better once I'd fixed that...

So, I've worked out how long my plugs need to be, to block off the respective holes when I come to drill the cross-holes. I've bought a piece of ali bar to turn the plugs out of, so maybe I'll have a go at that. Now, you may recall, I'd planned to go with a heat-assisted interference fit. But, as I've not yet managed to blag a free oven of a suitable size to warm the sump, I've decided to go with a nice tight push-fit, and I'll loctite it.

HELP! Which loctite should I use? There are so many to choose from..... I have a short window of opportunity to buy some tomorrow morning, so long as it's not an obscure one, which I'd like to do... Main requirements are: Copes with temperatures of 150-175oC, doesn't dissolve or significantly weaken in the presence of hot, thin synthetic engine oil, can cope with vibration. I just need a suitable product number (or selection of), I can try chasing some down before all the engineering stockists (that are open on Saturday morning) close. Many thanks.

Now, as pre-payment for that information, here are some photos & some wordy bits :)

As Andy suggested, I pre-drilled a small hole where I anticipated each main hole ending (more or less). Both tests succeeded, all 3 holes pretty well on target :thumbup: So, I went ahead & milled out the holes where the oil will drain into the pipes:

Subtle difference from the wax one; as I measured the drill location correctly this time, it turns out the short hole is actually in the sloping section (which is not yet sloped), hence the odd looking cutouts near the top left.

Looking straight down the longest hole, with the help of the red bar, you can see how accurate I was (or wasn't, as the case may be):

There's a slight lip where the red bar is (running the whole length of the pocket), about 1mm wide, which is where the pocket is slightly across from the hole (i.e. where the hole wandered slightly off course). TBH, blind drilling a 480mm hole with a 5/8" twist drill, I'll take that 1mm accuracy. I could probably better it with a gun drill, but at £1000+ for the coolant unit, before you buy the drill & the anti-waggle fixture (a sort of fixed steady for the gun drill shank), plus the inevitable contribution to Brown's failed economy (VAT, that is), I reckon I'm looking at the thick end of £2k. Worth doing if (when...) I put these sumps into production, but not before.

Anyway, as I didn't do much photography tonight, here's a gratuitous shot looking right up the holes (oo-err mrs):

Left to right, they are 230mm, 483mm, 342mm deep respectively. And now... good grief, is that the time? Time to eat....

andyf:
Loctite 668, perhaps? Datasheet:

http://www.grampianfasteners.com/files/Henkel%20Info/Technical/668.pdf

"Hot strength" is halfway down page 2, on the left - at 200C, it drops to half its strength at "room temp", but in your application it won't be under any real pressure, will it?

Andy

Divided he ad:
Ade,

Looks like a good job to me :thumbup:

Can't help much with the loctite things but I will add this: you should certainly test the plug thing at the full depth/longest plug on your test drilled piece of ali.

I say this because when I've driven plugs into holes with loctite on they have often bonded well before they have reached full depth. even gone so tight that a tapping stick doesn't help!

Making the plugs slightly smaller than you might think might be needed?

Hope it helps? Just wouldn't want you to screw anything up at this stage :)

Ralph.

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