Pre-cups - a solution?

[honda_is_the_best]

your gonna have a hard time convincing me that they were whole when they came out of the head..

[mk2diesel]

they work loose , hang a bit and get bashed by the piston over and over ... think of bending a piece of wire back and forth .... eventually the cup and hole wear enough to let the cup drop enough to cause the BIG BANG.....


 LUMIWELD will weld alum to steel  ( more like solder , to wick into the gap )

[arb]

Can you TIG the cups to the head somehow? could you get enough penetration between the alluminium and unobtanium to fuse them together? then get the head "decked" until the welds are flush with the rest of the head?

cant weld dis-similar metals.

You can, but unless you are one of the few Alchemy wizards (Metallurgist ) left in the world, the results vary from disastrous to unpredictable. Usually you get the metal of the lower melting point to melt first and then the higher to dissolve into it. Like the Nickel Chrome Cobalt alloy - you melt the Nickel first as there is no practical way to melt pure chrome. The Chrome and then cobalt will dissolve into the nickel...  I would not try this as the aluminum will be a huge heat sink. By the time you get the head hot enough to dissolve the cup, you'll likely have warped the head.

[honda_is_the_best]

ok guys, i stand corrected.

but let me put it this way.. we can not go to our shops, grab our mig guns, and start welding aluminum to steel, and inconel to aluminum.

we would need some sort of machine to get the cups friction welded or something. you know how they have one stationary piling, and the other one spins to make the weld? idk what the process is called, but its cool..

[Mark(The Miser)UK]

I have a BOC welding book somewhere from the 1950's and I'm sure it says you can weld inconel to ally
I'll have to dig that one out eh

The technique is to abrade the cups, then tin them, then oxy the cup until the ally just fuses...I'm still  with the I  can't believe  they fall out whole, brigade though

Clearly you guy's can't read English.
 You can't melt inconel into ally, you abrade it, tin it and then fuse the ally to the tin. Apparently good to 5 tonne per sq\inch tensile IIRC

[RadoTD]

Clearly you guy's can't read English.
 You can't melt inconel into ally, you abrade it, tin it and then fuse the ally to the tin. Apparently good to 5 tonne per sq\inch tensile IIRC

Hmm, 5 tonne/sq inch isn't very strong. Some alloys with inconel in them are getting towards 300,000psi tensile strength Tin also melts at a very low temperature.... would it fuse to an alloy that can withstand higher temperatures?

Oh, and I used to have some unobtanium arc rods that could weld aluminum to steel with my 60A buzz box I bought off craigslist for $20 and a few empty beer cans 
I tried welding stainless to wood, but the wood just kept burning

[jackbombay]

they work loose , hang a bit and get bashed by the piston over and over ... think of bending a piece of wire back and forth .... eventually the cup and hole wear enough to let the cup drop enough to cause the BIG BANG.....

  The HG let go before the pre-cup was anywhere close to falling out.

  The precup was way loose though, every combustion stroke it would get pushed out somewhat, and when the piston came back up it would cram it back into the head, the piston was pretty worn where it had been hitting the precup...