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moding a fly wheel

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seagull Compulsive Aussie Vee Dubber

4,979 posts · joined Dec 2003 ·

#387937
I would like to talk about STEEL fly wheels , and how to weld a new center in for a motor conversion > say to subaru or what ever turns you on .

1) what is the grade of matirial the fly wheel is made from ? codes ect

2) welding > the correct welding rods to purchase

3) method of cooling the fly wheel after you weld it
why this ? > some some one like me can machine it !
I use lime ( powder )

Ideas WES ??
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Desert Moose Cut Cut Cut

2,098 posts · joined Mar 2004 ·

#387942
Glad to see you have seen the light............:thumb

boof2332 Custom Title Time!

1,210 posts · joined May 2004 ·

#387962
What will you do...turn out the centre of the vw one, then machine the relevant centre to fit...would it help in strength if the centre was a clearance fit(I think that is what you call it when you drop it in liquid nitrogen to enable its placement) then weld after that????

How is the trike....how does the exhaust note of your extractors sound?

Matt

Baja Wes V6 Baja Pioneer

3,119 posts · joined Aug 2002 ·

#388215
seagull,

if you want a steel flywheel then just make a complete steel flywheel.

Standard flywheels are generally castings.

Steel flywheels are called for in higher drag racing classes as the cast iron type flywheels have a habit of exploding at high rpm due to their brittle nature and dis-like for cracks (which grow normally at the friction face).

You basically don't want to weld the castings unless you have too, and then only really to a similar material, not steel.
Wes - www.offroadvw.net - 200HP Quad Cam V6 in a VW Baja - with climate control... 🙂
www.taylorcycles.com.au - My DH MTB racing brothers shop.

seagull Compulsive Aussie Vee Dubber

4,979 posts · joined Dec 2003 ·

#388258
yes I agree with you are the vw fly wheels chrome molly ??
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tassupervee That really hurts doesnt it!

1,171 posts · joined Sep 2003 ·

#388262
Yep agree with Wes here.
By the time you either make or source your steel fly and then machine up a centre for it, weld it and then remachine it for true, you would be well advised to simply machine a complete custom fly.
As for the fly material? Dunno exactly.

L8tr
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Im not a complete idiot, quite a few parts are missing....

Baja Wes V6 Baja Pioneer

3,119 posts · joined Aug 2002 ·

#388796
I think most flywheel materials are a high grade cast iron. I think they are generally either grey cast iron or CGI (compacted graphite iron). CGI is stronger than your normal grey iron, partly because the graphite particles are smaller and slightly rounded (hence the name compacted). It is kinda like a cross between grey cast iron and SGI (spheroidal cast iron). CGI is difficult to weld properly.

Have a look at the 4th, 5th and 6th pic on this page - http://www.offroadvw.net/bajawes/V6_baja/december.html

I made my flywheel by putting a VW ring gear on the outside of the mazda flywheel. I did this by having a vw ring gear machines off an 1800 flywheel (as on those the ring gear is machined into the actual flywheel, and is therefore the same cast iron material as the flywheel). This meant the two should weld and work together quite well as they should be similar cast irons. My engine sees up to 8,000rpm every now and again and hasn't explode yet.

So I don't think your welding idea is good because you wouldn't want to weld steel parts to cast iron parts.

If you cut the center out of one flywheel and weld it into the center of another cast iron flywheel, then that's a whole other story and would work fine (and has been done for ages by off-road racers.
Wes - www.offroadvw.net - 200HP Quad Cam V6 in a VW Baja - with climate control... 🙂
www.taylorcycles.com.au - My DH MTB racing brothers shop.

choppa Seriously Crusin Dubber

190 posts · joined Oct 2002 ·

#391799
Neil.
You need an engineer for this, or a metalurgist.
But then they would be driving BMW's or Merc's, id guess.
And probably not watching this forum.
However I would doubt very much that VW flywheels are cast.
I machined a 1600 flywheel years ago and damn it was tough.
Id say they are some sort of Chrome moly.
I have read that you can weld to chrome moly without post weld heat treat, but that its not as strong as if PWHT was done.
But for us, id say its gotta be better than some cast iron ive seen.
Saying that, my Sherman Engineering conversion flywheel looks like cast iron. It hasnt busted yet. But then im easy on the clutch let up and i dont run slicks.
Bright bar has some chrome in it. Get a lump of that and machine that up for the centre.

Choppa

seagull Compulsive Aussie Vee Dubber

4,979 posts · joined Dec 2003 ·

#391801
its going to be a very big bit of steel .

your bros , was very hard when I machined the weld section , looked good , but shit it was hard going .
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nbturbo Veteran Volks Folk

2,171 posts · joined Dec 2002 ·

#391851
Neil- A mate of mine here is putting a Datsun 2lt into his Bay Kombi at the moment and he bought all the bits from some body in Castlemaine in Vic.The whole lot was only about $350 which included modifying the flywheel.I gave him one of my spare 1600 VW ones to convert, because his from the Bay was cast iron.It was away for less than a fortnight to have the Datsun centre welded in,and it looks like a great job.I will find out today who does this work,and will get a phone number for you.

seagull Compulsive Aussie Vee Dubber

4,979 posts · joined Dec 2003 ·

#391878
Cheers for that .
I been looking at your oval , some great work there .I have to come past and have a look when I come over .
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nbturbo Veteran Volks Folk

2,171 posts · joined Dec 2002 ·

#392098
Neil-checked my mate out about the flywheel-it only cost $290 for the adapter plate and to modify a steel VW flywheel that he had to supply(Which he still owes me for).They supply the machined centre to suit the specific relacement motor.Check them out at www.rodshop.com.au - phone them,my mate reckons they are really helpful.Oh and your welcome any time for a visit.nn[ Edited on 31-7-2005 by nbturbo ]

seagull Compulsive Aussie Vee Dubber

4,979 posts · joined Dec 2003 ·

#392102
Thats well priced .I have a look at the web page , thanks neil

O I will take you up on that offer for a shed visit 🙂
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1303Steve Scirocco Rare

8,650 posts · joined Aug 2002 ·

#392181
Hi

36 hp through to 1600 Type 1 & 3 motors all use steel flywheels. The type 4 motors use cast flywheels. The steel Beetle flywheel is a beautiful piece of metal.

Steve

seagull Compulsive Aussie Vee Dubber

4,979 posts · joined Dec 2003 ·

#392191
yep and very hard !
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