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New project, 1725 alloy flywheel.

R

RootesRacer

Donation Time
I bought a slab of 12 inch round 6061 aluminum.

Ive been planning to make a lightweight flywheel for some time, with the
winter round the corner and no fishing, I figured I'd convert that time into a flywheel on my new lathe/mill.

A question arises, which series clutch should I use?

The SV 7 1/2 cover is the lightest, but I have had problems with mine slipping under extreme power. The SIII-SIV 8 inch diaphragm clutch would probably hold more torque (I dont know Ive never used one). The SII-SIII clutch is probably the strongest, but is also very heavy, which undermines the whole light flywheel thing.

I also have a very lightweight 7 1/4" race clutch, but its so noisy, I was hoping not to use this one.

Any opinions, or option I've overlooked?
 
alpine_64

alpine_64

Donation Time
Jarrid,

i would go for the SI-II setup.. larger clutch will be better and longer lasting for your application. Also, i assume you are either going to go for a custom clutch.. or an aftermarket performance option.. in which case the slightly larger size might give you better options.. the comon street mod of volvo disk, MGB pressure plate and TO bearing on an early fly spring to mind.

Just my .02c

Are you going to do an alloy version of brian holmes flywheel? Or a alloy version of the modified rootes setup?
 
R

RootesRacer

Donation Time
Well Michael,

The SI/SII (they are actually different, the SII has more coils) is out of the question, simply its too heavy and I think I'd sooner use my light racing clutch and accept its clatter. Seems kinda silly to shed 15 lbs of iron and put on a 15 lb clutch cover.

Brian runs a T5 trans, so he has probably utilized a beefy clutch, with T5 compatible disc. I dont recall seeing his setup, so not sure what is magic about it.

Tell me more about the MG pressure plate, I recall reading something of this in McGoverns book (which I no longer have), but I recall it had an 8 1/2" disc.

A lightweight cover and 8 1/2" disc sounds appealing.

If you know specific applications for the disc and cover, that would be great.


BTW The stock SII flywheel sits at about 29 lbs, the slab of aluminum I just received is only 15 lbs and it hasnt been machined yet. Add on 3 lbs of stainless for the friction plate and I hope to be under 12 lbs.

Thx.
 
tigretr

tigretr

Donation Time
Jarrid,
Glad to hear you got your new toy up and running. I am curious to hear how well the lathe/mill combo works for you. As for the clutch, I would not expect you to use a stock alpine clutch. If you are going to the trouble of making an allow flywheel, why not find an aftermarket super light pressure plate and have a clutch disc made to fit your tranny. Since I put the 8.5 inch clutch on my car I have never had a slipping problem. With my 7.5 I had a lot of slippage. Of course slippage is also a function of disc material and pressure. My 7.5 was constantly in an oil bath which didn't help things at all. Kevlar clutches are much more forgiving in an oil environment. If you have had slippage problems in the past with the 7.5, I would recommend the 8.5 inch or better.

My winter project already in full motion is to upgrade my valvetrain to a full roller system. Crane billet cam, Comp Cams roller lifters, Manton pushrods, Fererra 462lb/inch springs, and Crower roller rockers.

Keep us posted on your progress.

Brian
 
64beam

64beam

Donation Time
Hi,

Is that a special type of aluminium designed for this type of application? Do you need to go through any hardening or coating processes? Just wondering as it is a fairly soft metal. If the 71/2" is a good size, could you use a different clutch to overcome the slipping factor? Are you limited by the rules in regards to clutches?

Regards, Robin.
 
alpine_64

alpine_64

Donation Time
RootesRacer said:
,

Tell me more about the MG pressure plate, I recall reading something of this in McGoverns book (which I no longer have), but I recall it had an 8 1/2" disc.

A lightweight cover and 8 1/2" disc sounds appealing.

Thx.
Click to expand...


Jarrid, will see if i can dig up the info.
 
R

RootesRacer

Donation Time
64beam said:
Hi,

Is that a special type of aluminium designed for this type of application? Do you need to go through any hardening or coating processes? Just wondering as it is a fairly soft metal. If the 71/2" is a good size, could you use a different clutch to overcome the slipping factor? Are you limited by the rules in regards to clutches?

Regards, Robin.
Click to expand...

Robin,

6061 is a decent grade of aluminum, easy to machine, relatively cheap, easy to get. It is very commonly used by folks that make alloy flywheels. 6061s softness has no impact on its use as a clutch because you need to install some sort of harder material for the clutch disc to wear on. The 6061 should not require any additional heat treatment (as far as I know).

From what I see from companies that make these flywheels is they use 1050 steel for the friction face on the flywheel side. 1050 is a high carbon steel, not sure why thats what they use, I doubt I will be able to machine it, so I was planning on using some form of stainless steel due to heat warpage resistance. But then again I'm no metallurgist.

Clutches are not scrutinized, I want one that holds up to racing abuse but still has street manners.
 
F

Frontalobotomy

Donation Time
Aluminum

Why not try 2024-T351 alum. rod or 2024-t351 plate. As far as the 1050 carbon steel if you want to go this route look into 11L17 stressproof or 11L41 fatigueproof or 1045 pump shaft quality material.
 
B

Bill Blue

Platinum Level Sponsor
RootesRacer said:
Robin,

6061 is a decent grade of aluminum, easy to machine, relatively cheap, easy to get. It is very commonly used by folks that make alloy flywheels. 6061s softness has no impact on its use as a clutch because you need to install some sort of harder material for the clutch disc to wear on. The 6061 should not require any additional heat treatment (as far as I know).

From what I see from companies that make these flywheels is they use 1050 steel for the friction face on the flywheel side. 1050 is a high carbon steel, not sure why thats what they use, I doubt I will be able to machine it, so I was planning on using some form of stainless steel due to heat warpage resistance. But then again I'm no metallurgist.

Clutches are not scrutinized, I want one that holds up to racing abuse but still has street manners.
Click to expand...

Jarrid, did a quick search on 1050, this turned up:
http://www.admiralsteel.com/products/200/hr1050.html

looks like a tough spring steel. I checked into the hardness as I am unfamiliar with the Rockwell B scale. A 90 on the "B" scale is at the bottom of the "C" scale. I think it will machine, no problem.

What kind of 3 in 1 did you get? I have always been fascinated with them, but never bought one.

Bill
 
Jim E

Jim E

Donation Time
The 140 and some of the 240 Volvo have the one inch 10 spline disc, the pressure plate also bolts to the Alpine F/W just requires a roller throw out.
Typically use the Volvo disc and a MGB plate that has the reciever for a carbon throw out. Pretty sure there are off the shelf race clutch packs for the Volvo.
 
R

RootesRacer

Donation Time
Frontalobotomy said:
Why not try 2024-T351 alum. rod or 2024-t351 plate. As far as the 1050 carbon steel if you want to go this route look into 11L17 stressproof or 11L41 fatigueproof or 1045 pump shaft quality material.
Click to expand...

Well like I said, I am no metallurgist, I looked at what the materials were used for the commercial offering and decided to emulate them within reason.

6061 is VERY available, I really dont know anything about 2024, let alone where to buy it.

As for the 11L alloys, why would you choose those (are they not low carbon and therefore non hardenable?).

Thx
Jarrid
 
R

RootesRacer

Donation Time
Bill Blue said:
What kind of 3 in 1 did you get? I have always been fascinated with them, but never bought one.
Bill
Click to expand...

I bought a harbor freight T5980, it was a downright steal and less than $.75 a pound all said and done. One major CON is that all the screws and dials are calibrated in metric. This wasnt even apparent until I turned the screws 10 turns each and divided the measurement by 10, this was becuase there was so much backlash in the gears and guides, you couldnt count on the dials at all. Needless to say, these machines need a bit of extra work before they are tight and reproducible, luckily there is a lot of info available on the internet.

It has a 6" by 8" table and about 8 X 15 machinable area over the bed.

The lathe center has 7 1/2" clearance over the bed and will therefore accept
a 12" diameter round, provided it is already pretty well balanced.

It came with a 4 inch 3 jaw chuck, some dead centers, a drill/tail chuck and thats about it.

Since then I bought a bunch of lathe tooling, a decent toolpost, a rotary table, some edge finding gear, mill holders and had a nice set of milling bits were donated.

I also bought 3 appropriate digital readout scales, of which I have installed and adjusted the X and Y. This gets around the oddball metric screws and allows the tool to graduate from a toy to something somewhat useful.

Upcoming purchases will include some thick alum plate to raise the table for milling so the Z axis doesnt have to be moved down so far to mill (makes the mill walk). Also I will be buying a 6 inch 4 jaw independent chuck and a better vice.

I have already machined some pretty neat parts, but now am getting ambitious (with the flywheel project).
 
B

Bill Blue

Platinum Level Sponsor
Jarrid, I don't know just how experienced you are as a machinist, but your comment about backlash makes me think you are just starting. If so, please consider this.

Backlash is a normal constituent of any machine that is not set up for CNC and the amount of backlash in a machine is not important. You simply must always make all adjustments into the part, not away from it. Thus, if you are turning a shaft that has a .100" step, back the tool away from the part 2 or 3 turns, then move the tool into the proper location, moving into the work. If you overshoot the mark by a few thou, back off 2 or 3 turns and try again.

Bill
 
R

RootesRacer

Donation Time
Bill Blue said:
Jarrid, I don't know just how experienced you are as a machinist, but your comment about backlash makes me think you are just starting. If so, please consider this.

Backlash is a normal constituent of any machine that is not set up for CNC and the amount of backlash in a machine is not important. You simply must always make all adjustments into the part, not away from it. Thus, if you are turning a shaft that has a .100" step, back the tool away from the part 2 or 3 turns, then move the tool into the proper location, moving into the work. If you overshoot the mark by a few thou, back off 2 or 3 turns and try again.

Bill
Click to expand...

Oh I am a newbie at machining, but the backlash on both the X and y were along the lines of twenty thou each. I can live with backlash but not that much. BTW, the digital scales totally negates the backlash, any you have to "feel" the turn of the screws to decide when you have broken through the slop and you are actually moving the bed.

The Chinese method for setting up the thrust clearances for the table screws was laughable. Ill give you a hint, it involved a bench grinder.:D

Its all better now, that is the cleanup of sloppy manufacturing, which is what you expect when you buy cheap Chinese machine tools.
 
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