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Re: fitting sigma discs to bellett
Posted: Fri May 01, 2009 12:56 am
by 2ldohc
Make sure you post pics!
I'm following this post with extreme interest as I want to go from 4 wheel drum and scary stopping to some decent stopping power

Especially if Antus and I get the fuel injected beastie in the shed up and running

Good luck Bellett65, keep up the good work!
Cheers,
Ross.
Re: fitting sigma discs to bellett
Posted: Wed May 13, 2009 10:09 am
by bellett65
I picked up the brackets and discs on Monday. Got home and realised i forgot to tell them that the caliper holes should be 12mm. Well I now have 3 stuffed (were new) 12mm drill bits. The brackets are not made of mild steel, so back to the shop to get the holes reamed out. The steel is some alloy that is used on hard wear surfaces and earth moving bucket edges. All is fitting up well. But my calipers do not resemble the ones that are in the piccies that I put up. they are alloy. I just hope the 14" wheels fit. Or it might be of to the local shopping centre carpark for some wheels LOL

- DSC00317.JPG (156.76 KiB) Viewed 36968 times
Re: fitting sigma discs to bellett
Posted: Wed May 20, 2009 3:39 am
by Beetle
Bellett 65 Any further information to hand on how the fitting up job went? If you have finished the fitment, what is the braking performance like? Did the wheels fit, were the caliper brackets correct etc etc. Do you have a template available?
Is it all smiles?
Re: fitting sigma discs to bellett
Posted: Wed May 20, 2009 3:45 am
by Beetle
Stickman How on earth do you pull bearings apart swap them around and put them back together and get them to work properly? Are there special tools or machining involved? If it is possible to adapt the bearings it may well be a much easier way of fitting discs. Any info would be appreciated
Re: fitting sigma discs to bellett
Posted: Wed May 20, 2009 4:56 am
by bellett65
I have not got the brackets back from machine shop. I forgot to ask for the caliper holes to be 12mm. I stuffed 3 new 12mm bits trying to ream them out. Then I found out the engineer had used a steel called Bisalloy, it is used in highwear areas such as scraper blades and rock buckets. So I am now waiting on the call to pick them up, so I can workout where the machining has to be done.
Re: fitting sigma discs to bellett
Posted: Sat May 30, 2009 8:37 am
by bellett65
The sage so far. 2weeks to get 4 holes reamed ou to 12mm. Now back to get some machining.
Piccies below of the dry fit. Have to get 1.5 mm machined off the caliper mounting area. This is mainly to get the caliper more central, but also to give some clearance to the wheel as the caliper does just touch the rim.
Re: fitting sigma discs to bellett
Posted: Tue Jun 02, 2009 11:14 pm
by Beetle
Guys does anyone know where I can get some rubbers to fit between the master cylinder body and the reservoir.
The original rubbers on my master had perished and I have tried both brass abd fibre washers, but still have a leak between the two.
Would plumbing rubbers as used in toilet fittings etc work or would the brake fluid stuff them? Cause I reckon there would be a size to fit in the local plumbing supplies joint.
Somebody please help turn my frown upside down
Re: fitting sigma discs to bellett
Posted: Wed Jun 03, 2009 4:07 am
by bellett65
Try PBR kit K7308X Boot should fit
Re: fitting sigma discs to bellett
Posted: Wed Jun 03, 2009 5:44 am
by Beetle
Thanks bellett65
by the way, will you need longer wheel studs to allow enough thread for nuts to do up when you bolt on the alloy wheels?
Re: fitting sigma discs to bellett
Posted: Wed Jun 03, 2009 7:14 am
by bellett65
Beetle wrote:Thanks bellett65
by the way, will you need longer wheel studs to allow enough thread for nuts to do up when you bolt on the alloy wheels?
Yes I will need them. Quite possibly Commodore but i will have to wait and see once the clearances are worked out. Also longer brake hoses. The brackets are back at the machine shop getting milled down to 9mm Because they supplied me with Bisalloy instead of mild steel. They cannot be washed down to size. The steel used is extremely strong about 6 times stronger than mild steel of the same thickness.
Any one thinking of doing a brake conversion should have a look at
http://www.hoppers.com.au/articles/Guid ... 20Cars.pdfThe advice is very helpful.
This one is the Rules according to the law.Another good read and not as hard to achieve as one would think.
http://www.infrastructure.gov.au/roads/ ... 5_Section_LG_Brakes_3Feb2006.pdf
I am putting down a document that outlines the process that I am going through. With piccies.
Peter
Re: fitting sigma discs to bellett
Posted: Wed Jul 01, 2009 2:07 am
by Beetle
Does anyone know what kind of steel is used in brake rotors. Cause I'm sure if you could get the right sort of steel and the right size an engineering shop could make areplacement rotor as per the original specs
Re: fitting sigma discs to bellett
Posted: Wed Jul 01, 2009 3:03 am
by JT191
Beetle wrote:Does anyone know what kind of steel is used in brake rotors. Cause I'm sure if you could get the right sort of steel and the right size an engineering shop could make areplacement rotor as per the original specs
They are cast iron. The exact alloy of the originals might not be as important as what is being used now, because metallurgy has improved a little in 40 years. Most metal suppliers will not lend technical information on brake rotors for liability reasons. Some disk manufacturers say they use "gray iron".
I've had rotors turned from solid rounds. I vaguely remember about $100 USD each for the iron and over $350 USD for the labor for each one. I come close to a heart attack every time I try to remember the details, and things get mercifully less accurate over time. These are solid, not vented.
Hindsight: AP makes the best selection of smaller disks, vented and solid. Vented in the same diameter as original would be $375 USD each. Hats and four piston calipers would be less than the cost of the cast iron material and the cost to rebuild and make parts for the original calipers.
Re: fitting sigma discs to bellett
Posted: Fri Sep 30, 2011 4:06 pm
by Simmo
If you use a gh sigma disc setup, its a very easy conversion. My Dad did it a few years ago in less than a day. Before he started he got a spare set of brake hoses modified so they bolt to the bellett at one end and the sigma calliper at the other end, he also got a set of wheel bearings the same od as the sigma bearings and the same id as the bellett bearings. Then everything basically bolted straight up except I think you have to swap the calliper mounts and redrill to suit the bellett. Done, and with no machining.
Re: fitting sigma discs to bellett
Posted: Mon Nov 21, 2011 3:44 pm
by 65bellett
Silly question Simmo you don't happent to know the bearing number do you?
Re: fitting sigma discs to bellett
Posted: Tue Nov 22, 2011 6:34 am
by Simmo
Sorry buddy, it was years ago. Dad walked into cbc bearings with both sets of old bearings and it didnt take them long to find the right ones.
Re: fitting sigma discs to bellett
Posted: Tue Nov 22, 2011 6:02 pm
by JT191
One of the original bearings has a part number with a slash dividing the number for the inner race and rollers/balls, and the outer race. The same inner race and rollers/balls can be used with several different outer races, and they offer several different OD outer races to be paired with the inner pieces.
That might be how simple it was for Simmo's dad. Measure and match the alternate outer race or inner race and rollers/balls.
With the unsealed type bearings, mixing spindles and hubs that were not originally designed to go together sounds a lot less complicated than with the more modern sealed bearings.
Re: fitting sigma discs to bellett
Posted: Sun Nov 27, 2011 5:02 am
by CQGT
65bellett,
Prior to the first Bellett Nationals that my brother Joe and I had attended, 2007, I did some research on this same
subject.Using the sigma hubs and rotors.
I approached my local CBC bearing shop, and supplied the info. required. ie. bearing part numbers of both hubs
and what would be able to be purchased to do a swap.
The outer bearing was easy. They are both the same part numbers. And will fit numerous brands of vehicles and
are available as a set. Set "A". LM11949/LM11940. Paired as per JT191 referral.
The inner bearing does not come as a set, as they are not a popular size for the motor industry. [as I have been told].
Part numbers are. Inner race [cup]. LM67010. Inner cone. [bearing]. LM67043. The seal is the Sigma seal, C7017
[mits 4067116]. I advise that they are not cheap, and not readily available.You may have to wait a while for them.
I have purchased these bearings and have done a 'dry run' with them in assembly. Using a PR20 stub axle and steering
arm. My next part was to try to use the Sigma caliper bracket, not to have one fabricated. This I had to 'shelve' , as
I was spending too much time in modifying parts from other brands for my sedan project, as I found more rust in it,
more than I had expected. This meant fabrication of panels for the upper control arm chassis side members.
I hope this wil assist you and other forum members and Bellett owners.
By the way. If anyone knows of a Ford Escort GT, not sure if single or twincam, laying around. The bearings are the
same part numbers as the Pr20. The hub may bolt straight on.?? Food for thought. Now I've Planted the seed.
Enjoy..............................Dave.
Re: fitting sigma discs to bellett
Posted: Sun Nov 27, 2011 11:14 am
by 65bellett
Thanks for all the info guys. I already have a set of modded stub axles and Galant disks on a car and a spare set under the bench but I am always keen to hear of a way to do it with a minimal amount of machining.
Re: fitting sigma discs to bellett
Posted: Thu Apr 26, 2012 3:20 am
by Glenn
Gents, been reading this thread while back and went past a wreckers today so decided to see what TP magna disks etc look like. The calipers seem to be different to that shown. Hard to tell, but maybe larger ?
Glenn
Re: fitting sigma discs to bellett
Posted: Thu Apr 26, 2012 3:22 am
by Glenn
while there, saw a N13 Pulsar. Not sure of the PCD of these though, I suspect a bit smaller.
Glenn