Soooo Lets just say that this thing is tough... It does not want to be sanded, grinded, or anything...

Sandpaper and a whatchamacall it just takes off the aluminum in like dust particles.

Grinding wheels are chunking up like no tomorrow... doesnt grind it off.. it eats it up.. like a tinsy bit at a time

Anyone have any suggestions?

I'll take a pic of all the pieces i've tried...

You must be the guy that wrote these build specs for this ship we are building. Cause I have absolutely no clue what it is you are doing.

QUOTE (Andyrew @ Mar 24 2005, 05:36 PM)

... Lets just say that this thing is tough... Anyone have any suggestions?

oh - let's just tell us WTF 'this thing' is, for those of us who haven't been following along every nuance of the Andyrew reality series...

but basically, it's really hard to grind aluminum - it doesn't respond very well to abrasives. it forms aluminum oxide. aluminum oxide is a well-known abrasive...

aluminum likes to be machined. a cutting tool in a lathe or mill will make short work of whatever you're trying to do.

a carbide burr in a die grinder has always given me good results.

of course, i have no idea what you're actually trying to do ...

He's trying to open up a threaded collar to fit over koni hydralics. I'd take them to a machine shop, if you grind away at it who knows when you are getting to the point of failure (cutting into the backside of the outside threads) - that would be hard to control with a grinding tool by hand.

Heh, sorry..

Its.. ermm..



The threaded piece. Im grinding it down on the inside so it fits over my shock.

Its like .1 in to small. The coil over has a lip on the inside about that much that the shock fits over. So I know it can be ground down, but it doesnt want to be.

I dont think it can be lathed or machined... That would be a big bit...

QUOTE (Andyrew @ Mar 24 2005, 06:15 PM)

I dont think it can be lathed or machined... That would be a big bit...

i once toured a machine shop that made the hatchways into which submarine watertight compartment doors were fit. a single billet of stainless steel about 12' in diameter and about 3' thick.

that shop could machine a whole 914 from a single billet of steel on a 5-axis CNC machine. somehow, i think your flange can be machined because - that's how they made it in the first place, yes?

they'd chuck the flange part into the jaws and use a boring bar (basically, an internal cutter) to take it off.

or go get yourself a carbide cutting burr for your die grinder and BE CARFEUL. i used to get mine from the Snap-On truck but These Guys look to have pretty good deals. i wish i'd known about them when i still lived in NV !

oh - and think about the loads, especially in rebound. compressive loads at the ends of the dampers can be on the order of 3X your spring rate...

You need a lathe and a boring bar. Easy.

Andrew, come on up to my place this weekend and we'll see what we can do. I have all the right tools. I'm just a little concerned that you are going to cut right into the backside of the threads.

Chris

Whatcha got goin this weekend? I probably have work whatever time your thinking (3-11pm) and sunday's easter... And dad wont leave working on the house remodel on saturday.

I REALLY apreciate your offer!

got to go to work.

Thanks for the offer, sorry I have to refuse.

Andrew

I'm home tonight @ 6:00 and won't have anything going till Sunday. I'm in Santa Cruz Mountains so it's a bit of a drive for you, but if you're desperate I'm home. PM for directions/Phone#

Chris

You're not taking off much, maybe try a cylinder hone or glaze breaker if you have one around. Just keep the stones well oiled.

It will take you about ten minutes on a lathe. The setup time will take you more time than the actual work. Please do it right.

QUOTE (Andyrew @ Mar 24 2005, 04:39 PM)

Whatcha got goin this weekend? I probably have work whatever time your thinking (3-11pm) and sunday's easter... And dad wont leave working on the house remodel on saturday. I REALLY apreciate your offer! got to go to work. Thanks for the offer, sorry I have to refuse. Andrew

I'm free Sunday morning.....7 am too early for you???

QUOTE (ArtechnikA @ Mar 24 2005, 07:25 PM)

i once toured a machine shop that made the hatchways into which submarine watertight compartment doors were fit.  a single billet of stainless steel about 12' in diameter and about 3' thick. that shop could machine a whole 914 from a single billet of steel on a 5-axis CNC machine.

I once toured Dowdy Canada that made landing gear for 747's (and the USAF Osprey)...they had a lathe that you could fit a locomotive into...totally fuching huge.

They also had CNC machines coming out of the ying-yang, plus a test booth that simulated a 6 story hard landing.
Wild stuff.


End highjack.

why didnt you just buy the right size collar?

Aaron.. Not as much fun!

Besides, they didnt have it...

70 bucks vs ???

Mike, I got church!!

I think I'll try the machine shop... Hey, At least I stocked up on grinding wheels!!! lol

I hope that 70$ was for both sleeves otherwise you got ripped.

yup both.

Its at the machine shop.
Should have it done monday.

On to the engine removal!!!

QUOTE (Andyrew @ Mar 25 2005, 03:12 PM)

Its at the machine shop. Should have it done monday. On to the engine removal!!!

how much are you going to get charged?

might have been cheaper to buy new Koni shocks

Said 25 bucks.

QUOTE (Andyrew @ Mar 25 2005, 03:24 PM)

Said 25 bucks.

that is a good price.....it would have cost you that much in gas to drive to my place or Chris'

QUOTE

Coil over "boring"

I thought you were saying this topic was boring

lol
boaring.. that better?

I dont know the spelling.. lol

Mike, Yup me and dad discussed it.. lol

Right now im trying to make my exhaust system "anti perminent"...

Weld a bolt for the muffler bracket to the body.. Ok, im fine with that.. bolt up up nice and snug with washer and plastic bushings, Alright looks good! Weld the nut in place on the bolt DOH!
Next, Weld a bracket from one side of the exhaust to the other.Ok.. bolt it up to the trani, while no way for you to remove the bracket because its welded to the mufflers... DOH!

The perches are in the machinests hands, They had a nice machine shop and I trust their abilities. If they screw it up. Oh well.

Andrew

QUOTE (Andyrew @ Mar 25 2005, 05:12 PM)

Its at the machine shop. Should have it done monday. On to the engine removal!!!

Did you ever get finished with these? and if so how did the machine shop work out for you?

Bob

Andyrew,

Check the dimensions before you commission someone to do the work. Going stricktly on my (poor) memory, you may end up with an extremely thin wall section after machining the ID. Remember to consider the root diameter of the thread; that will be the OD. I went through a similar excercise with a friend's 914 and convinced him to not machine the ID, as in his case the resultant wall was way thin. Just check things out before you start.

Andy

Lol, I got these done 3 weeks ago...

Yes, the machine shop worked perfectly fine. 25 bucks and it was better than I could have done.

Ran it at the autocross (check my sig) and it worked like a charm.

They already had a "factory" machined lip about one cm on the ID that would fit over the shock body perfectly. So I knew that the collared perch could take the less material.