BMW V8 dry sump from billet

[AdeV]

OK, so I did a bit more on this yesterday afternoon, after the GP qualifying.. First job was to mill off the end of the plugs, so I would have a nice flat plate again:

First cuts, with a ripper, took me to within 0.5mm of flat:


The final 0.5mm was taken with a regular end mill. Looks like I overshot by a tiny amount:


The next job is to drill the cross-holes; these will bring the oil flow out to the side of the sump. The setup is "interesting" to say the least:


Lucky I never finished that taper adapter clamp for the lathe, as here it is helping to hold the sump down 

Final photo for today, I centre-drilled the three holes:



No pics, but I then drilled the short (85mm) hole with a 5mm, 10mm and finally a 5/8" drill. Repeated for the 2nd hole (105mm). Unfortunately, drilling through the plug, the 5/8" drill knocked the piece that's supposed to separate the two holes, out of place 

Therefore, plan "B" will now occur: I'll have to drill into the plugs from the underside, between the side holes, tap them & insert a bolt. That won't prevent them from unsticking when drilled, but it should stop the plug portion from wandering out of the hole. So long as the outer plugs stay firmly glued up, I can live with it I think. More later... after the GP.

[AdeV]

Disaster Averted.....
...or, On The Importance Of Taking Notes

I don't know when I made the mistake. Probably on Saturday, seeing as I didn't do anything on Sunday. Or maybe it was when I made the plugs. I will never know...

Having glued the plugs in the other week, it occurred to me I hadn't made a note of how long they were. After some head-scratching, a plan was hatched. I shoved a piece of welding rod down each hole, and marked it where it met a convenient rib. By withdrawing the rod & laying it flat on the sump, I could see the end point & mark/measure accordingly. The plugs ended 20mm, 50mm and 80mm deep as applicable. Great, says I, and made the above centre drills at 20, 50 & 80mm. I then drilled the 50 & 80mm holes... because they were the shorter (& thus easier) ones to do.

By random good fortune, I didn't drill the 3rd hole, instead I went out and had tea in a pub in Wales...


Today, I drew up those holes on my Visio master plan set - and discovered that the 20mm hole (which is ~16mm in diameter, and therefore would be around 12mm from the front edge of the sump) would, in fact, foul the mounting holes (which are drilled all the way through the block - those being 6mm in diameter & 9.5mm in from the edge; a 0.5mm overlap...) This would have holed the front of the sump, causing all kinds of mayhem and annoyance....


The solution is not elegant, but as I've already drilled two of the holes, is the only one open to me: I've moved the hole inboard by 3mm; thus providing 2.5mm clearance from the mounting hole, which should be plenty. In hindsight, the cross-holes should have been a further 8mm inboard; as it is I've centered the drill on the end of the plugs, instead of measuring to "just miss" the end of each one - which would have been a far better solution.

Still, at least I didn't scrap the sump. A close shave, that one...

[Stilldrillin]

Still, at least I didn't scrap the sump. A close shave, that one...

By `ek Ade! 

THAT mustn`t happen now.......

Wishing you Good Luck, and clear thinking, from now on....... 

David D

[Divided he ad]

Sounds like lots of fun there Ade         is how I see it in smileys 


Very happy you didn't lose it this far in 




As David said "Wishing you Good Luck, and clear thinking, from now on.......    "      





Ralph.

[AdeV]

Just a quick update: I'm still dissolving the taps away... they're taking their sweet time. After syringing in a little conc nitric acid, and waiting 24 hours:



Clean away the brown snot, re-load with acid, wait another 24h, rinse & repeat...

[madjackghengis]

Hi Ade, I've been following your log on the sump from the beginning, and while it is not exactly related to anything I'm doing myself right now, your work has certainly been intriguing and informative, demonstrating how much that can be done if one does not follow the petty recommendations of teachers and instructors, as to limits of equipment and machines.  My one big question is related to the taps you are removing with the use of nitric acid.  I don't seem to be able to find the point at which you broke them, and needed them removed.  It's a minor matter, and I am interested in the concentration of the acid, as I remove broken taps on a regular basis, but I am in the dark still on when the calamity occured.  I am very interested in the success of your acid method of removing them, as I've never used that method, but if it works well, would add it to my tool kit, but the missing link, the breakage, and how it occured would be of interest as well.  You've definitely shown the possibilities of working beyond the advertised limits of the machine, and have turned out a fine piece of work, particularly considering the constant set ups, and tear downs necessary.  mad jack

[AdeV]

Hi Ade, I've been following your log on the sump from the beginning, and while it is not exactly related to anything I'm doing myself right now, your work has certainly been intriguing and informative, demonstrating how much that can be done if one does not follow the petty recommendations of teachers and instructors, as to limits of equipment and machines. 

Thanks Jack - I guess it helps that I don't have any teachers (other than the readers & contributors to this forum, who are usually too late to warn me of the dangers on account I've already done it...), so as far as I can tell, if I can physically fit it on the machine, then it must be possible....

My one big question is related to the taps you are removing with the use of nitric acid.  I don't seem to be able to find the point at which you broke them, and needed them removed.  It's a minor matter, and I am interested in the concentration of the acid, as I remove broken taps on a regular basis, but I am in the dark still on when the calamity occured. 

Oops, I see I didn't write up what I was trying to do, at least on this thread...

Basically, having plugged the end holes with the specific-length plugs, I then set up to drill into the side. I drilled the first hole, and everything went well. But when I drilled the second hole, the end of the long plug (which I drilled through) came loose, and migrated into the first hole, effectively blocking it. Here's a couple of C-o-Cs:



The hatched areas represent the plugs, the shaded the holes. This is the view looking down from the top. I drilled the left-most hole first, then the middle hole; that's when this happened:



Using a piece of welding rod, I managed to shove the plug piece back to where it should be, I then decided to drill into the plugs, tap them, and screw in a length of threaded rod, the idea being this would hold each plug section in place - both while I drilled the final hole, and also in service. The plugs don't have to be 100% oil tight internally, "near enough" will do - although the outer bungs DO need to be oil tight, otherwise leaks will ensue. Fortunately, the outer bungs will be easy to replace & re-glue if required.

I am very interested in the success of your acid method of removing them, as I've never used that method, but if it works well, would add it to my tool kit,

Well, my experience so far would suggest it's viable IF you can wait the requisite days (weeks) it's taking... I'm not too fussed about the timescale, since I've got other projects I can get on with. If this were a production system, I'd have drilled the buggers out by now... The acid I'm using is, to the best of my knowledge, 78% concentrated - i.e. white fuming nitric acid - not the red stuff that Lew mentions. I don't believe it's possible to buy more concentrated stuff "over the counter". It requires hand protection & breathing protection when in use, and common sense and a fully heightened sense of caution goes a long way towards using the stuff safely.

You've definitely shown the possibilities of working beyond the advertised limits of the machine, and have turned out a fine piece of work, particularly considering the constant set ups, and tear downs necessary. 

Much appreciated, thanks As I say, ignorance (in this case, of the limits of the machine) is a great help...

[madjackghengis]

Hi Ade, I appreciate the answers, you've cleared up what I have up to now, just assumed, and I fully understand your difficulties with plugs, having done similar jobs, and had to tie up loose plugs before.  If you are following my build on the radial engine, I removed a number of #4 taps physically, and had one I ended up milling out a pocket, pulling out the pieces, and tigging it back up, and had I known about the acid, I would have allowed the time and etched it out, as I still don't like the reminder the weld lines give me of that broken tap.  On larger taps, I'm accustomed to being successful getting them out welding nuts of larger sizes to them, or using a make-shift EDM set up, because I'm too lazy to jump to the EDM project I haven't got to yet, but using acid would definitely be the easy way, from the sound of it.  I'm looking forward to seeing the sump on an engine, and it running, hopefully soon. mad jack

[Powder Keg]

This is a great thread AdeV. I just got done reading the whole thing You are doing a great job!!! I like seeing people push machines to their limits and beyond! Any updates

[MattTheHat]

You, sir, have balls the size of church bells!

Amazing stuff, Ade.


-Matt

[Divided he ad]

You, sir, have balls the size of church bells!

But hopefully not the shape! 




How goes the dissolving of the taps Ade?




Ralph.

[AdeV]

OK, a brief update: Nothing new so far 

For whatever reason, the taps are still there, obstinately enough. I don't know if it's lack of surface area that's caused the dissolving trick to fail, or quantity of steel vs. the quantity of acid I can get in there; maybe it needs some heat.

So, I think it's time to dig them out mechanically. John (Bogs) suggested using a hole cutter to come down around the tap & remove it that way. Unfortunately, I don't have any suitable hole cutters, so I think I'll do something similar, but will mill a chunk away around the taps (enough to get something on them to remove them with. I'll then put a straight pin down to hold the plugs - or, plan C(2), a tapered pin (assisted into place with a large hammer), or Plan Q(4), a straight shank pin with a plug of some kind glued/screwed/otherwise held in place.

It's high time I got back on with this project... so, watch this space...

[stovebolt]

 I couldn't find the size of your taps but if they aren't too big, you could make a hole cutter or annular cutters I think they're called, this is the only pic I could find, this was made specifically to locate springs , but it's the same principle.  I just drilled/ reamed a piece of drill rod/silver steel  and cut teeth in it with a dove tail, you also might want to cut some flutes.   If you try it I would recommend you counter bore the ID to just a little short of the teeth so the plug doesn't friction weld and  while using clear chips often.       

   



 

[AdeV]

Well, after FAR too long a hiatus, while waiting for the nitric acid to do something... anything... I gave up waiting & got back in the saddle...



Clockwise from top left:

1 - Milled down to the broken off taps, lower & lower until I was pretty much underneath them

2 - Here we can almost make out the snapped off taps, sticking up. Not sticking up far enough to get the pliers on them, unfortunately

3 - After a while, I managed to pull out the remnants. Cleaned up the bottom of the hole (well, a bit anyway)...

At this point, I was scratching my head wondering what to use as a dowel pin ( I still need to pin those plugs, remember)... Then, inspiration! I have several broken 6mm cutters (), so I ground a couple of broken ends down to length and...

4 - there they are, very gently battered into place with a hammer & punch. A nice tight fit... but not so tight as I'd worry about them coming out under the stress & vibration of the engine running at full chat - so, I shall make a block to go over the top, and that will be glued/screwed/loctited in place.



Anyway, with the taps out, and the plugs pinned, there's no more excuses.... I can now proceed.


Onwards!

(erm, after Christmas probably...)

[NickG]

Ade,

Good to see you're back on track with this now though. I absolutely hate anything to do with cars at the moment due to all of mine being broken, but I'll still be watching!

Just about to go and try some of the graphite you kindly sent for the stirling, the wife will be wondering what the hell happened to the bed sheets soon

Nick

[Divided he ad]

Bout time     


Looks like it'll do nicely 


After Xmas!!?  I'm planning on that being the time I get a bit of peace and quiet in my workshop!  Got the sparky coming on Sat am to wire up all my new strip lights and sockets     I'll be able to work in the dark again (you know what I mean!?)




Looking forward to seeing this on the motor      




Nick, You machining Graphite in bed?  I've often soldered sat on mine but not used the lathe! 






Ralph.

[Mike Cole]

Ade
 Just read this thread over a couple of days. I also tried the acid trick with a broken tap. I tried HSo2 ( if i rememeber my chemisty right) . Took a couple of days but it loosened it the end.
I will call in sometime as i am so close.

Mike

[NickG]

I was just about to embarrass myself with lack of chemistry knowledge then, so I googled it and I was right, it would have been embarrassing!  This acid must be bloomin strong to dissolve taps - sounds scary!

Ralph  I do know a fellow model engineer that had his lathe on a wheeled trolley that he wheeled from under the stairs and used in the kitchen though! 

Nick

[Mike Cole]

Thinks I was wrong with my HSo2   :thinking more of H2SO4.

I did not try to disolve the whole tap ,just to  wiggle it out.

When I worked for the Oil Industry we had to boil some nasty stuff. Not nice having your lab

disolve around you.  We had the gardener mowing the lawn outside and the mower fell down a

hole as we disolved the drainage pipes. That was meant to be our clean discharge

I left as soon as possable

Mike

[winklmj]

A day late and a dollar short.

Know anything about electronics? You could build this next time:

http://groups.yahoo.com/group/GrizHFMinimill/photos/album/1530925054/pic/1072364455/view?picmode=original&mode=tn&order=ordinal&start=1&dir=asc

[NickG]

I thought you meant that which is sulphuric acid, apparently h2so2 is a reduction of that, I thought it was hydrogen sulphide! No wonder I dropped a level chemistry after a year!

[AdeV]

Interesting stuff chaps, thanks for all the acid comments (ho ho ho); I'm not sure what effect H2SO4 (Sulphuric acid) would have on aluminium, nor HCl (hydrochloric). The good news is, the Nitric acid (HNO3) has done very little damage to the ali (a bit of leaching which will clear when I skim the top). It was working its way through the taps, but too slowly for my liking.

Winklmj - I've heard of spark erosion, but don't know enough about them really... I'll definitely take a look at building one though, I should have enough electronics ability to do that.

Anyway.... on with the show; did a bit tonight, one of those jobs which I wouldn't have needed to do had I not buggered up the taps in the first place.... making a plug to fit the hole.

First operations were to mill a block of ali down to size, then part it off its stock:



Then I used a radius cutter to get as close to 6mm radius as possible; unfortunately, I don't have a 3mm radius cutter, so a 1/8" had to be substituted in. It's only a few thou ought, and this isn't a size critical piece.

So, once the corners were all radiused (roughly) & the burrs filed off:



It nearly fit:



And, after an hour in the freezer, and few vigorous meetings with the Plastic Hammer of Battering Things Until They Bl**dy Well Fit, it DID fit:



 

There's a smidgeon of Loctite in there too; and tomorrow I'll drill, countersink, tap and screw the piece into the hole as well, just to make absolutely sure it doesn't come loose.

[Divided he ad]

Hmmm Looks like it was meant to be there! 


You home then?
Or did you take some work with you? 



Good to see you back on it     I wanna see this car running!   





Ralph.

[AdeV]

You home then?
Or did you take some work with you? 

Don't worry, I haven't forgotten that I'm supposed to be phoning you.... I just had forgotten until now! 

Deffo tomorrow (not now, hungry, going home to eat...)

[AdeV]

I've been  again..... so, a little more progress was made today. It'll be the start of the racing season soon, this sump needs to be finished...

So, where are we at? Well, I've taken about 5mm off the top, so that the engine side is now to dimension. I've taken a couple of mm off the bottom too, although there's between 8 and 11mms more can come off there yet. I'll certainly be taking 8 off, to bring the thickness to 50mm, not sure if it's worth pursuing the extra 3mm yet - the deepest hole on the inside is about 45mm; a 2mm floor thickness doesn't leave a lot to the imagination, although it would be plenty - provided there's no accidenally extra-deep holes anywhere 

So: Here's the obligatory occasional arty moody shot:



Hey, I liked it. Here's one where you can see all the warts:



I figured a trial fit on the engine might be a fun idea. It also ensures I've not over-cut anywhere when I rotate the engine through ~360 degrees. No metal-on-metal noises = A good thing. There'll be a gasket in there as well, so the innards will all clear nicely.



The pipe sticking up shows the location of the oil pump. There will be 3 of those, albeit a bit shorter than that one (only a few cms), which will plug onto spigots in the side of the sump. That part will become clear later. I also thought I'd better make sure I could actually fit those pipes in, bearing in mind the cockup I made when drilling the side entry holes. Fortunately, there's plenty of room:




So... I got to thinking about those tabs, as that's the next tricky bit of machining. And the first issue - I couldn't quite decide how far out the holes were from the side of the sump! A caliper from the centre of the hole to the edge of the sump suggested 12mm (so, with a sump width of 250mm, and the other hole the same distance away, 274mm centre-to-centre). But a steel rule reckoned 276mm from centre-to-centre (or edge-to-edge, whatever). How to resolve this 2mm dilemma?

Wax!

I broke out the waxy prototype, stuck it on the mill more-or-less straight, and decided to try the 276mm spacing (i.e. 13mm from each side):



2 holes, 276mm apart. Trial-fit on the engine:



Perfect 

Nice one, Machinable Wax

More tomorrow, I hope.