Hello:
Its been some years since I posted. If y'all remember me I worked in a paper mill as a Ghostbuster, under a maint mgr I used to lovingly call "brain dead"
Some might remember this complaint...

Carl, I made a call on this condensate pump, wet end brg is shot and your supervisor put his foot on the pump, looked me in the eye and said "it feels ok so we ain't changin it"
Then it blows in a few days. Who are you gonna back Carl?...me and this spectrum?...or his FOOT?
Joe, I realize you know what you're doing but take in account Claude's years of experience and expertise on knowing pumps.

Pulled the pump apart and several blades worn off, bearing fried.
.......heh, did this jog your memory?

Well Carl is now gone and sinking a paper/pulp mill in Castlegar.
He was about to get fired, and funny how rats know when to scurry off.
This budget he did up for a shutdown showed work of around $200K less than what was needed, fudging the book to show he was saving money and miraculously found another job before he got fired.
The young kid that comes in behind him ended up being one of the best maint mgr's the mill had in 10 yrs. Like Danny/Don/Sam said to me "ride it out Joe, it goes in waves"
...our mill permanently shut on Oct 06.
The town is peaceful and quiet.
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Well anyway, best thing that ever happened to me, although I do miss doing vibration, just don't miss the management.

Since 2000 I have been making my own snowmobile CVT kit parts as a part time hobby job. It is a clutch kit for skidoo snowmobile models. Since I've been on my own and dedicate the time to work the biz I've done alright for the winter.

Snow season is gone so now I'm twiddling my thumbs a bit, working on a few summer projects. I am still interested in vibration, I just wish there were more companies in my area that were believers in it. Our local SKF rep couldn't muster up some vibration work if I pointed a gun to his head.

I am doing a little side project for myself. I want to go snowmobile grass drag racing on grass/clay in the fall months. It will be good for my little business, people seeing my name, advertising.
I'm building an 800 cc engine. The latest one churned out 186 hp on an inertia dyno at 9200 rpms = WOW!
Most 800 cc engines out there run up to about 180hp but have found more hp with some exhaust technology.

I went all-out and bought complete ceramic bearings $650USD and just paid for 2 titanium connecting rods that will handle 125hp each to the tune of $1380USD = oww. My visa hurts.
I know some guys running this stuff and its unbelievable the way their engines accelerate when they leave the starting line. holy

My Questions....
** Balancing my 2-stroke engine crank **
The crankshaft is made out of 5 parts and are all pressed together.
http://pic20.picturetrail.com/VOL1600/486172/1703322/242997969.jpg
http://pic20.picturetrail.com/VOL1600/486172/1703322/242997979.jpg

I know there is:
Pure rotating weight [crankshaft with no rods]
Pure reciprocating weight [Piston, piston pin, needle bearings]
Hybrid weight [connecting rod beam]

Question] How can I go about balancing this crankshaft after it's assembled with connecting rods installed?
Question] Can the crankshaft be balanced without the connecting rods installed [only rod pins]?

I have a feeling that I can't balance the crank with the connecting rods installed.
I don't know much about balancing but I like to learn more.

Question]...What would be the smallest machine that could balance this?
Something like this?
http://www.ghbalancer.com/pages/sw.htm

Question]...To find out who can balance this crankshaft, would I look up Balance Machine manufacturers and ask them if they have a list of customers who've bought a particular model and research that customer to see if they have a business in balancing?

...reason I ask this is maybe I should buy one of these balance machines and get in to the business of balancing 2-stroke engine crankshafts and CVT's "clutches"
The only company in our city "Siemens" does not do this type of balancing. They only do field balancing with a really old IRD beater.

Guys, I'm spending so much damn money on this engine, but I'm saving a ton by doing a lot of work myself and I want to extract every single little thing I can out of it since it will be dedicated engine to run only 500feet.

Here is an engine my best friend built. It's a 985cc engine that made conservative 203hp at
http://revzone.phanfare.com/
Click on the little box.
Then scroll your mouse over the small pictures and look for the one named [warming up 985cc]
Then the next one 203hp at 8700 rpms.
The dynamometer is an inertia dyno. The engine has to accelerate (3) 250 lbs discs.
I can't explain the overwhelming emotion of standing there doing dyno runs making an engine work so hard.

This message has been edited. Last edited by: Dynamo^Joe,

Sorry, I don't know squat about balancing crankshafts.

You might get a better response in the vib/align/balance forum.

By the way, let me be the first to say:

WELCOME BACK!

Dynamo,

I don't know of any way to balance with Con-rods attached. The most common way is to put bobin weights on crankshaft journal equal to a fraction (say 50%) of the total reciprocating weight and then spin balance (2-plane) the crankshaft with the two bobin weights attached. My guess is that you will find that the "magic fraction" for reciprocating weight amount is probably by trial and error to find what works between the balance machine and the engine going full tilt. I suggest you talk to several engine shops to get their opinions, useful or not, before starting the whole process.

Here is a link to some help:
http://www.rpmmachine.com/engine-balancing.shtml
Good Luck

Walt

You may want to post your question at Eng-Tips, http://www.eng-tips.com/index.cfm

It seems like there are more automotive engineers over there.

Sounds like the money your forking out you could build a one-piece crank. 16 cyls are perfect balance and there are downward sprials from there. Timing, firing, angles, length of stroke, etc.. do play a part in operation and its smoothness.

After my long-windedness; following Steve's advise is probably your best bet.

Joe, I was only thinking of you a couple of weeks ago and meant to go back and lookup your address - good luck in your ventures.

ePete...HEY man, I'll do some browsing in that forum.

Walt, thanks for the info, that balancer looks like you can drill material out of the crank throws without removing the crank from the centers.

Steve, I got lost over at eng-tips, i'll have to sign up and try their search function.

Sam, can't build a 1-piece crank, the connecting rods are one piece, so everything pressed together.
My norampac mail address is gone, but my shaw.ca address is still working.

thanks for info.
I will slowly continue to research this, but right now have to work on a suspension im making.