[pp-TG]

Any body have a good way of fixturing for facing down Motor cylinders...

I have some cylinders off an artic cat and i had pressed in new sleeves i would like a way to fixture them up and face them off but i would like it to be universal so i can do other brands and sizes any one do this or have a good method? And were is a good place to hold from?

Thanks in advance....

Travis

[JWB_Machining]

Not exactly sure what these parts look like or there dimensions and most likely others can give better advice than I can but have you looked into collets?

[RICHARD ZASTROW]

Travis, Do you refer to individual cylinders (AKA jugs) or multiple cylinders in a common block? On a lathe or mill or?

Individual "jugs" have a pilot area at the base which can be held in a fixture plate bored to fit the pilot area. Fixture should be faced perpendicular to the pilot bore. Fasteners to clamp the jugs obviously must clear the cutting zone.

Be careful not to remove any more material from the surface than absolutely necessary. Spray on some blueing and remove that with your cutting tool. Any metal removed reduces the "squish band" in the combustion chamber. This can cause pre-ignition which in turn will cause piston failure, "Donut holes".

The proper squishband clearance can be adjusted by gasket thickness.

HTH Dick Z

[pp-TG]

Thanks Dick Z,

Yes it is Individiual Cylinders(AKA Jugs) . That is kind of along the lines of what i was thinking but i was hopeing there was a more versital way of doing all kinds of different sizes with the same setup because there is no one around me that does this and there is a few other people that would like me to do it...

Thanks again for the help

Travis

[RICHARD ZASTROW]

Travis, You could develop a fixture with a bore larger than the largest pilot (the one on the crankcase end of the jug). That over-sized bore could then receive insert adaptors to fit various sized jug pilot ends.

Good Luck, Dick Z

[wrechin2]

This is the set up I am going for on the engines I work on.

[RICHARD ZASTROW]

Oops!! I thought you were referring to a lathe set-up. However, that plate type of set-up should work fine on a mill as well.

Dick Z

[pp-TG]

"Oops!! I thought you were referring to a lathe set-up. However, that plate type of set-up should work fine on a mill as well.

Dick Z "


Actually i was referring to a lathe set-up... And i am thicking of going with an independent 4 jaw chuck. The only issue i am having is finding a 4 jaw for my lathe(okuma LB9) it has a flat nose spindle and i can not find one to bolt up so i may have to make an adapter plate and it may get costly and time consuming... So not sure if it is the way to go yet or not....!

Thanks, Travis

[NC Cams]

WIth the lathe setup, you'll lose the "deckplate" efffect that your mill setup offers. Deckplates do wonders for bore roundness and head clamping flatness as far as distortion removal. THis gets to be a real issue when/if you go for lots of compression and the ultimate in sealing.

Roughing on the lathe is one thing, finishing to the ultimate might be best done in the mill with deck plates and a facing cuter - K-D had such a cutter for the Crovair that could be adapted to do face cutting on the mill or lathe.

Trouble is, most hobbyists won't pay that much for the dead nuts job. And yet they'll wonder why a guy who takes the time to do it. will outrun their sleds day after day.

Speaking of the benfits of bore roundness, we did some experimentation when I was at TRW with regard to bore roundness on the infamous Olds diesel. Redid one using all the hot rod tricks, FLow'd and pocket ported the heads. Decked block, deck plated block for OS pistond, line hone, and even had head studs and crank balance. Basically the works. Car was a fleet test car for Marathon Oil.

THe car was once the scourge of the fleet. When done, it was the most desirable to drive, ran the quietest, started easiest, got best mileage and had lowest oil consumption and lowest level of crankcase contaminants. WHen someone tells you that this hot rod stuff doesn't mean that much, I know of and can prove otherwise.i

[pp-TG]

Thanks NC,

What do you mean by "deckplate" effect? And i look into k-d tools did not see any type of cutters but i will keep the serch on... Is it a type of fly cutter?

[NC Cams]

Deckplate { plate that bolts to the deck on a block the helps simulate the distortive efftect of head on cyl bores. Clamping of bolts has shown to distort bores by as much as 0.008" (sm chvey 400 circa 1970).

KD tools had a DIY head refacer for the 60's Corvairs. Essentially it was a had spot facer of cyl head. However the cyl sealing surface was recessed below the "deck" of the head as the head also had to retain the fore/aft/side/side alignment of head.

Device was essentially a top had shaped cylinder. THe "brim" held a cutter. The "hat" of the cutter registered into the recess htat held/aligned the cyl sleeve. The cutter was then adjusted to equally cut the depths of the cyl's as they sealed at the base of the recess.

Essentially it was a hand driven fly cutter. Most of the people working at KD today wouldn't know what I"m talking about - I got mine in 1972.

[pp-TG]

Thanks NC,

[pp-TG]

This is the set up I am going for on the engines I work on.

What do you plan to face this setup off with? I would like to use a fly cutter but cant find anything avalible for this size....(6" Min.) I only want to skim them.(.002-.003) so face mills tend to leave a bad finish if the nose radius is not fully ingaged.

Thanks,