Casting in alloy

[Piero]

hi

just a thought,

how could a alloy gearbox bellhousing be cast.

is viable as a one off????

 

[piman]

Hello Piero,

Sand cast for a one off, which means having a pattern made then finding a foundry to do the job. Viable (economically), I would say not unless the job is for a very valuable vehicle? Usually easier to make up an adaptor plate?

Alec

 

[Piero]

I am trying to retro fit a gearbox to a bellhousing,

yes a adaptor plate would be the easy option, only the original bellousing is very very weak.

its very thin cast alloy,

i was thinking of a new thicker bellhousing with no need for the adaptor plate if a can get the diamentions right

 

[brightspark]

as above .designing and getting a pattern made for a one off would be astranomical .as would the price of getting it cast ,then factor in the price of machining

 

[Fazerruss]

if you're are accurate with cutting n fabrication and have a decent workshop then one can be made out of steel. Start with the engine and gearbox flanges and make a cage. Fill in the gaps with plate. You will need a big milling machine then to square up the mating surfaces.
PPC did it but their technique was questionable

 

[500e]

Tell us more ?
I have the occasional casting made, (usually in bronze) have friend who makes patterns, the expensive bit, casting not so if you wait for a pore on that material there is a small foundry near Wells in Somerset who does one off's

 

[mfletch]

What's the bellhousing off

 

[KemppiFrog]

We did one for an Alfa to VW box. The old man had a proper engineering training pre-war, which included hands on casting. He advised on the pattern, which we made, then had it cast at a local foundry, followed by machining the ends to match the engine and gearbox. It is time comsuming, but worth it. Can't remember the costs, but they were low. This was in the 70s, the car is still running, but with a Hewland now.
KF

If you are good with lining up and measuring, Fazerruss' fabrication method can be done without much machining, if any. The dowels on the flanges locate the parts pretty well.

 

[wookie]

I am trying to retro fit a gearbox to a bellhousing,

yes a adaptor plate would be the easy option, only the original bellousing is very very weak.

its very thin cast alloy,

i was thinking of a new thicker bellhousing with no need for the adaptor plate if a can get the diamentions right

Just an idea... Make an adaptor plate and bolt it to the existing bellhousing then build up the bellhousing with car body filler where it needs more strength and then use it as the pattern for sand casting ? Saves a lot of work making a pattern ?

Then you would have a brand new stronger bellhousing and no adaptor.

I don't know if that would work but someone more knowledgeable will be along in a minute...

 

[Fazerruss]

I'm not sure about ally but from what i've seen on various documentaries about cast iron the pattern needs to be a ?% bigger to allow for shrinkage of the metal as it cools

 

[brightspark]

I'm not sure about ally but from what i've seen on various documentaries about cast iron the pattern needs to be a ?% bigger to allow for shrinkage of the metal as it cools[/quote patternmakers use a shrinkage or so called patternmakers rule .the graduations are calibrated for varous metals for shrinkage . its a bit tough sh ,./,././,t if u buy one and dont notice till u have cocked up a load of your jobs a friend of mine cut an 1/8 th of a steel rule at college by accident on the guilotine . there was a lot of head scratching for a few weeks till it was noticed http://artisanfoundry.co.uk/store/p...d=206&osCsid=932b7bbb45af1524a27fd64a7709dd8e

 

[Piero]

Not sure if this is going to help any,

But the bellhousing is from an early Triumph GT6 mk1
The gearbox I want to fit is from a Fiat twin cam as in a Mirafiorie

I might just make a mock up adaptor plate out of MDF first, JUST to see if its going to work.
I hate modified gearbox tunnels on Spitfires/GT6,s

so if it fits and is do-able, I might move on to the second stage of a stronger bellhousing with no need for the seperate adaptor plate.

 

[Wedg1e]

Not sure if this is going to help any,

But the bellhousing is from an early Triumph GT6 mk1
The gearbox I want to fit is from a Fiat twin cam as in a Mirafiorie

I might just make a mock up adaptor plate out of MDF first, JUST to see if its going to work.
I hate modified gearbox tunnels on Spitfires/GT6,s

so if it fits and is do-able, I might move on to the second stage of a stronger bellhousing with no need for the seperate adaptor plate.

The Spit/Herald tunnel was only compressed papier-mache anyway, wasn't it?

 

[Piero]

yes but the the good quality carpet sets are moulded

 

[ronan]

Doubleboost is the man to ask if its casting you want to know about.

 

[Piero]

where are you Doubleboost???

 

[AndyStobbs]

Could you have the bell housing braced with alu flat bar to add in some strength?

 

[Piero]

That was my second thought Andy

 

[doubleboost]

Casting is possible
You would need a pattern (shape you want) then a core mould (to do the inside bit)
Other way is to make one from high density foam
This is buried in sand molten alloy poured the foam burnes away leaving a alloy casting (very messy)
Have a look on my youtube plenty of casting vids there

 

[bigegg]

I, personally, would use foam - the problem with foam is that it is one-use, so if you short-pour or otherwise cock-up your pour, you are going to need to make a new pattern.
If I thought that I could sell a few, I might even go with lost wax (which can be duplicated)

www.backyardmetalcasting.com is the place to ask.

be warned... casting is addictive!