adding weight to a piston

[elwood]

hey guys, I found a crack in one of my pistons so I ordered single piston from egge, the new piston is 42.2 grams lighter than my others,
I need some advice on how to add the 42.2 grams to the new piston.
could I tig a even amount in each end of the wrist pin ?
Im open to ideas please.
thanks

[Fordors]

That's an oz. and a half! I would buy seven more pistons, the lighter reciprocating weight will make it feel like a completely different engine.

[elwood]

hey fordors, i cant afford to buy seven more pistons, hah.
pluss if i change the reciprocating weight it will throw the ballance off.
so i just realised the old wrist pin is thicker than the new one, so i swaped pins and now its only 16.2 grams light.
im thinking i can add that to the pin with tig ?

[Karl Wolf]

Find a piece of brass that will fit in the center of the pin... Or aluminum...
Karl

[Pete]

NO WELDING on the pin....Put a plug in it. .002 press fit.

[Ronnie]

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Phone Egge

R

[elwood]

i phoned egge ronnie, they said duu, i dont know what to tell yu.
good idea pete, and karl
heres my fix,
I found a long shank bolt it had abought a .006 press fit, I cut a length of it and then rolled it on my belt sander till I have a .003 to .002 press fit, then ground down the length till it weighed 16.2 grams.
iv got the plug in the freezer now.
tomorrow Im goanna get some green locktight, and press the plug dead center of the pin.
whatta yu think ?

[paul2748]

Remember that the Lock Tite will add weight

[makemc]

could you take 16.2 grams off the other seven pistons so as to match the new one, just a little off each side of the skirt should do it..

[uncle max]

Originally Posted by elwood

i phoned egge ronnie, they said duu, i dont know what to tell yu.
good idea pete, and karl
heres my fix,
I found a long shank bolt it had abought a .006 press fit, I cut a length of it and then rolled it on my belt sander till I have a .003 to .002 press fit, then ground down the length till it weighed 16.2 grams.
iv got the plug in the freezer now.
tomorrow Im goanna get some green locktight, and press the plug dead center of the pin.
whatta yu think ?

Nice to see those triplebeams can be used for other things...

[Ronnie]

Originally Posted by makemc

could you take 16.2 grams off the other seven pistons so as to match the new one, just a little off each side of the skirt should do it..

That would make the dynamic balance way off as the bob weight changed.

R

[Jack E/NJ]

Just about anything you do will change the dynamic balance of the whole rotating assembly when using a piston with characteristics different from the original.

Jack E/NJ

[Ronnie]

Originally Posted by Jack E/NJ

Just about anything you do will change the dynamic balance of the whole rotating assembly when using a piston with characteristics different from the original.

Jack E/NJ

Making up weight that is short on the reciprocating weight will be ok.The piston,pin,lock rings and rings (and bolt)are all reciprocating weight.Getting the weight back with bolt will work,as long as it doesn't come loose to touch cyl wall.Not much choice other than all new pistons and re balance to the new bob weight.Cheapest and no balance change.All this is less critical if the engine wasn't balanced to begin with.

R

[Walt Dupont--Me.]

Originally Posted by elwood

i phoned egge ronnie, they said duu, i dont know what to tell yu.
good idea pete, and karl
heres my fix,
I found a long shank bolt it had abought a .006 press fit, I cut a length of it and then rolled it on my belt sander till I have a .003 to .002 press fit, then ground down the length till it weighed 16.2 grams.
iv got the plug in the freezer now.
tomorrow Im goanna get some green locktight, and press the plug dead center of the pin.
whatta yu think ?

Great idea Pete, and your doing a great job Elwood. Walt

[Craig CT]

Originally Posted by elwood

hey guys, I found a crack in one of my pistons so I ordered single piston from egge, the new piston is 42.2 grams lighter than my others,
I need some advice on how to add the 42.2 grams to the new piston.
could I tig a even amount in each end of the wrist pin ?
Im open to ideas please.
thanks

Hi Elwood; If you haven't done so, I suggest you weigh the one you're replacing, just incase it's heavier than the others. Also do you know why the piston cracked? Good luck, Craig.

[Flathead]

If you press your weight into the pin you want to be sure it doesn't expand and foul up the fit to the rod and piston. Just a thought.

[lee34]

you might check to see upper temperature limits of the loctite .I think it may not hold the temperature needed.Also grinding your plug on the belt sander you will not get total surface contact because of the the surface is not accurate machined.If the pin expands at a faster rate than the plug the plug could come loose and rub the cylinder walls.(not a pretty condition) . just my 2cents lee34

[THE "A" FAMILY]

what if you used something liquid. and poured it in. maybe into the piston, itself. you could do some practice runs, to test the dry weight. then test with different types of heat? maybe on an old piston. just trying to brainstorm.

[Ol' Ron]

I don't like working on Ferrari's to complicated, that's why I like working on Flatheads, don't have to worry about this stuff.

[elwood]

thanks for the input guys, im going to the machine shop tomorrow to get a nice plug made, your right lee, my home made plug is not even at all, the belt sander left flat spots on it.
thanks Walt, im trying to make it up to this pore ol eab for over torque the one head, hah. sigh. still cant believe I did that. duhh .

[Ol' Ron]

We learn by doing and making mistakes. Back in the day we'd cut the bottom of the piston off at the bottom ring, balancing was never an issue, Unfortunately there wasn't anyone around that did that. Bells in Patterson NJ did it for 80 dollars I think. I built a balancer for rods and pistons that allowed me to find parts that are equal. The Janns Pistons we used were all over the map and we got pretty good with a die grinder on the balance ring in the bottom of the piston. When It gets a little warmer I'll dig that stuff out and post it. You don't need a scale. Considering all the "Stuff" we did to these engines and got away with it, makes me realize what a great engine it is. I'm sure a precision but one would last forever. Take care Elwood.

[jdl]

Ellwood, if you use locktite use the right one..maybe this one, read the discriptions then decide. you might not need any with a press fit.

http://www.henkelna.com/industrial/p...UID=0000000HZO

here is the web site..

http://www.loctite.com/index2.php?cc=us

[Shu47]

Ol' Ron...I love your real world input. It always make sense.

[columbiA]

I know the Canadian & US 59A wrist pins were a different weight The pistons were different weight too,but the combined weight of piston & pin were the same.

[Fordestes]

what would be wrong with filling the pin with J.B.Weld and then the excess weight could be drilled out to precisely what you need?
Fordestes

[Marv]

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What would be wrong with putting 8 matched pistons in, instead of a cobble job that may come apart and ruin a good flathead block? Just my thought. Marv

[Dave D]

I'd be more concerned with wondering when the seven remaining pistons were go to start cracking.....

That's a hell of a lot of work to have to do over again.... and again... and again.