Compomotive MS 1380 Wheels, refurb, engineering, and use
Posted: Sat Aug 02, 2014 2:49 pm
Hi all
this will be a pretty brief thread to show what sort of things can be done to use wheels, not originally destined for use on Italian cars, and in no way fit for your ride initially.
Firstly, these are owned by Mike (Buzzed) whom i had been discussing retro wheels and styles with for a short while. It became quite clear, and expectedly i guess, that certain brands of wheels here in the uk were very rare over the ponds in Australia, and vice versa.
He had showed me the sort of wheel he would really like to see on his Fiat initially, but would also grace many of his 70/80's era cars, his newly acquired Sud for one of them.
I identified the style and taste, best produced as one of my favourites, Compomotive MS range of wheels, but he wanted a width and dish that is almost none existent today, as it generally died out with the rear wheel drive cars of the same late 70's early 80's, so trying to find some 30+ years later, and in 4 x 98 pcd, 58.1 or 58.6 centre bore, from an era that 4 stud rear wheel drive Alfa's was going to be all but impossible.
However, where there is a will, there is a way, and i knew that Mike was coming over to England for Goodwood, and a trip round old blighty, so, as a gent with the same addiction to old skool cool as myself, we just had to hook up, chew the fat a bit, and see if there isn't a way to overcome the seemingly unobtainable unicorn horn of wheel rims.
I had ready for him, a collection of wheels to show him, as i bought them, in a bit of a state, painted badly, and what paint there was applied was trying its best to unattatch itself at a rapid rate!
BUT, they were Compomotive MS 1380's, in other words the classic Pent Star design, in 13" diameter, and a whopping 8j (9") width, and a ridiculous offset giving a huge deep dish effect, almost perfect but for the fact that they had been assembled as a "set" from mismatched pairs, probably from an Opel Manta GT, early VW or other GM hub'ed cars. That means they were 4 x 100mm pcd, different centre bores etc etc, but are they the right sort of wheel for Mike?
Yes!
So a plan was hatched and a deal done, and this is how I have overcome some of the fit and mismatch issues so that Mike will end up with his awesome dream rims.
Firstly, lets get rid of the awful paint, and get back to where these wheels were 30+ years ago, stripped to virgin alloy. So to begin with a chemical strip, followed by a relatively soft shotblast. This is because ultimately the deep dish section will be getting polished, and if you try to polish a harsh deep grain shotblasted area, it can take literally forever! So twice the cost to do it this way, but the results are far better in the long run.
Now i can see the wood for the trees, time to measure up exactly where we're at for the engineering.
For starters, 2 of the wheels have got the large/tall centre cap turret, and 2 haven't, so these need machining down to be equal, and accept the same shallow type of Compomotive centre emblem.
Secondly, 2 of the wheels have a centre bore of 63.4, and 2 were 57.1, more evidence of the former GM/Vauxhall use, so again 2 of them needed to be machined to match the larger 63.4mm, so that spigot rings can be used on all 4 wheels to reduce the hub fit down to the Italian friendly 58.1mm Mike needs.
Both these jobs were done on a lovely old large bed lathe, and manually might i add, rather than vertically on a cnc mill, where the job can only be as true as the mounting and "clock" centering of the workpiece itself. These came out perfect using old skool methods and machines, and pretty quickly too once loaded up and spinning, so all 4 wheels are matching on the outside, and accept the reducing spigot rings to fit snugly onto our Alfa/Fiat/Lancia sized hub protrusions.
Next phase is to prepare the wheels ready for powder coating, and this is where i have a small delay, Grrrr!
I have converted a wheel/tyre balancing machine to be a constant and extremely true wheel spinning machine, to help get a really nice and consistent sand/polish to any outer rim or circular area, but the centering cone needed for such small centre wheels is missing and i am still waiting for it to arrive in the post from the bloke who has confirmed he still has it
I will sand all rim and edge marks from the wheels, and start the sanding off for the final polish on the deep dish so that once at Mikes end, it isn't a huge task to polish the powder off and get a high quality shine without 3 weeks of labour, a full set of finger nails and 5 boxes of abrasives!
That said, no-one ever told him that would be easy, just very worthwhile!
this will be a pretty brief thread to show what sort of things can be done to use wheels, not originally destined for use on Italian cars, and in no way fit for your ride initially.
Firstly, these are owned by Mike (Buzzed) whom i had been discussing retro wheels and styles with for a short while. It became quite clear, and expectedly i guess, that certain brands of wheels here in the uk were very rare over the ponds in Australia, and vice versa.
He had showed me the sort of wheel he would really like to see on his Fiat initially, but would also grace many of his 70/80's era cars, his newly acquired Sud for one of them.
I identified the style and taste, best produced as one of my favourites, Compomotive MS range of wheels, but he wanted a width and dish that is almost none existent today, as it generally died out with the rear wheel drive cars of the same late 70's early 80's, so trying to find some 30+ years later, and in 4 x 98 pcd, 58.1 or 58.6 centre bore, from an era that 4 stud rear wheel drive Alfa's was going to be all but impossible.
However, where there is a will, there is a way, and i knew that Mike was coming over to England for Goodwood, and a trip round old blighty, so, as a gent with the same addiction to old skool cool as myself, we just had to hook up, chew the fat a bit, and see if there isn't a way to overcome the seemingly unobtainable unicorn horn of wheel rims.
I had ready for him, a collection of wheels to show him, as i bought them, in a bit of a state, painted badly, and what paint there was applied was trying its best to unattatch itself at a rapid rate!
BUT, they were Compomotive MS 1380's, in other words the classic Pent Star design, in 13" diameter, and a whopping 8j (9") width, and a ridiculous offset giving a huge deep dish effect, almost perfect but for the fact that they had been assembled as a "set" from mismatched pairs, probably from an Opel Manta GT, early VW or other GM hub'ed cars. That means they were 4 x 100mm pcd, different centre bores etc etc, but are they the right sort of wheel for Mike?
Yes!
So a plan was hatched and a deal done, and this is how I have overcome some of the fit and mismatch issues so that Mike will end up with his awesome dream rims.
Firstly, lets get rid of the awful paint, and get back to where these wheels were 30+ years ago, stripped to virgin alloy. So to begin with a chemical strip, followed by a relatively soft shotblast. This is because ultimately the deep dish section will be getting polished, and if you try to polish a harsh deep grain shotblasted area, it can take literally forever! So twice the cost to do it this way, but the results are far better in the long run.
Now i can see the wood for the trees, time to measure up exactly where we're at for the engineering.
For starters, 2 of the wheels have got the large/tall centre cap turret, and 2 haven't, so these need machining down to be equal, and accept the same shallow type of Compomotive centre emblem.
Secondly, 2 of the wheels have a centre bore of 63.4, and 2 were 57.1, more evidence of the former GM/Vauxhall use, so again 2 of them needed to be machined to match the larger 63.4mm, so that spigot rings can be used on all 4 wheels to reduce the hub fit down to the Italian friendly 58.1mm Mike needs.
Both these jobs were done on a lovely old large bed lathe, and manually might i add, rather than vertically on a cnc mill, where the job can only be as true as the mounting and "clock" centering of the workpiece itself. These came out perfect using old skool methods and machines, and pretty quickly too once loaded up and spinning, so all 4 wheels are matching on the outside, and accept the reducing spigot rings to fit snugly onto our Alfa/Fiat/Lancia sized hub protrusions.
Next phase is to prepare the wheels ready for powder coating, and this is where i have a small delay, Grrrr!
I have converted a wheel/tyre balancing machine to be a constant and extremely true wheel spinning machine, to help get a really nice and consistent sand/polish to any outer rim or circular area, but the centering cone needed for such small centre wheels is missing and i am still waiting for it to arrive in the post from the bloke who has confirmed he still has it
I will sand all rim and edge marks from the wheels, and start the sanding off for the final polish on the deep dish so that once at Mikes end, it isn't a huge task to polish the powder off and get a high quality shine without 3 weeks of labour, a full set of finger nails and 5 boxes of abrasives!
That said, no-one ever told him that would be easy, just very worthwhile!