Castings

Castings

In the early decades of the 20th Century many manufacturers, including magneto manufacturers, made use of a new zinc based alloy to die cast some of the component parts of their products. Probably considered to be an excellent choice at first, it was soon discovered that, in time, this material, commonly known as 'pot metal' deteriorates with age. This is due to a destructive, inter-crystalline corrosion process referred to as 'zinc pest' or 'zinc rot'. Typical symptoms of this problem include numerous cracks, splits, blisters or pitting followed by dimensional changes as the material slowly expands and it ends up in a very weak, brittle condition. The rate of deterioration is greatly increased in damp, humid conditions. Unfortunately, damage is rarely limited to just the zinc alloy parts as the expansion process usually causes problems with adjacent components too. Sometimes the problem is very obvious but in the early stages, things might appear to be not too bad until an attempt is made to dismantle the magneto. As soon as they are disturbed, affected parts often just crack and fall apart as soon as a screw is loosened. 
On these EIC end housings, the alloy had expanded to such an extent that the cam rings were seized solid. We wanted to re-use the cam rings so needed to get them off. Inevitably, our attempts to remove the cam ring  caused the casting to fracture in both cases. Disappointing perhaps but not really a problem - these end housings were already too far gone. Even if the cam rings had come off ok, with the casting suffering from zinc pest, there would have been no point in attempting to get a press fit with a new bearing.....
There is nothing that can be done other than to replace the affected part. In order to keep some of these affected magnetos in good working order, we organised the manufacture of foundry patterns  and arranged for small batches of new castings to be made.

We are often asked if we can convert fixed ignition magnetos to manual control of advance and retard. Quite straightforward as long as a replacement bearing/cam housing is available. This conversion is commonly requested for BTH magnetos and we fairly quickly ran out of spare housings. We now have the new castings for two types of BTH bearing/cam housings available to satisfy this demand.

We have used these castings in the course of overhauling and repairing our customer's magnetos and are pleased to make them available as a stand alone item for others with access to the required facilities to carry out the necessary machining themselves.
PLEASE NOTE - These are all new castings which will need to be machined before they can be used. Sorry, we are not able to supply ready machined castings. Nor can we supply detailed drawings at the current time.
In the pictures below, the red parts are the foundry patterns made specially for us by a time served pattern maker.

HOW TO BUY: These castings can be purchased direct from us, For all customers, both in the UK and overseas, the price indicated includes postage/packing. There is no more to pay, everyone pays the same all inclusive price wherever they are located. A full invoice will be included with all purchases. Payment can be taken using PayPal by clicking on the Buy Now button  associated with each casting.

Dixie base castings
Dixie Base
This casting can be used on a number of different types of Dixie magnetos including Model H, Model M, Aero AE and possibly others. Made from LM25 aluminium and then heat treated, they machine very easily.
PLEASE NOTE - This is a bare casting only. It will need machining before it can be used. At very least this will involve drilling/tapping holes. 
Dixie base casting
Dixie base casting: £ 62.00
(includes P&P to anywhere in the world)

'Round' ML Bearing/face cam housing
This casting can be used on all 'round' ML magnetos using face cams. We can supply two types, one with the advance and retard on the left, one with it on the right. The choice of a left or right casting is determined by the direction of rotation of the magneto plus your preference for 'tight wire' or 'slack wire' advance. More information is on the Advance and Retard page in the Technical section.

Made from LM25 aluminium and then heat treated, they machine very easily.
PLEASE NOTE - This is a bare casting only. It will need machining before it can be used. This will involve lathe work and drilling/tapping holes. 
ML Face cam end pattern - left
ML face cam end pattern - right
Round ML bearing/face cam casting - cable on LEFT: £ 41.00
(includes P&P to anywhere in the world)
Round ML bearing/face cam casting - cable on RIGHT: £41.00
(includes P&P to anywhere in the world)

'Square' ML Bearing/ring cam housing
This casting can be used on all 'square' ML magnetos using ring cams. We can supply two types, one with the advance and retard on the left, one with it on the right. The choice of a left or right casting is determined by the direction of rotation of the magneto plus your preference for 'tight wire' or 'slack wire' advance. More information is on the Advance and Retard page in the Technical section.

Made from leaded gunmetal, they machine very easily.
PLEASE NOTE - This is a bare casting only. It will need machining before it can be used. This will involve lathe work and drilling/tapping holes. 
ML round cam end pattern - left
ML round cam end pattern - right
Square ML bearing/ring cam casting - cable on LEFT: £ 51.00
(includes P&P to anywhere in the world)
Square ML bearing/ring cam casting - cable on RIGHT: £ 51.00
(includes P&P to anywhere in the world)
Currently
OUT OF STOCK
More on the way!

BTH end housing - clipped cap type
BTH Bearing/cam housing - clipped  cap type 
This casting can be used on many BTH magnetos including KC1, KC2 and KD1, KD2, KDV magnetos.  Made from LM25 aluminium and then heat treated, they machine very easily.
PLEASE NOTE - This is a bare casting only. It will need machining before it can be used. This will involve lathe work and drilling/tapping holes.
BTH bearing/cam casting - clipped cap type: £ 42.00
(includes P&P to anywhere in the world)

BTH Bearing/cam housing - competition type 
This casting can be used on many BTH magnetos including KC1, KC2 and KD1, KD2, KDV models. Made from LM25 aluminium and then heat treated, they machine very easily.
Cap for BTH competition housing 
This casting can be used on the competition type bearing cam/housing listed above. We have included a stub on the casting to make machining of the gasket side easier. It is then machined away when working on the outside. Made from LM25 aluminium and then heat treated, they machine very easily.
PLEASE NOTE - These are bare castings only. They will need machining before they can be used. This will involve lathe work and drilling/tapping holes.
BTH bearing/cam housing casting - competition type: £ 56.00
(includes P&P to anywhere in the world)
Cap casting for BTH competition housing: £ 24.00
(includes P&P to anywhere in the world)
BTH competition housing and cap - both castings: £74.00
(includes P&P to anywhere in the world)
If you are buying these BTH castings in order to convert to manual advance and retard, you will also need the parts shown in this picture. We do not supply these as they are already available from Dave Lindsley - davelindsley.co.uk - that's where we buy them from when we need them. The cam ring from the fixed ignition magneto could be modified to suit manual control or Dave can  supply the correct ring as well.

PLEASE NOTE - These are all new castings which will need to be machined before they can be used. Sorry, we are not able to supply ready machined castings. Nor can we supply detailed drawings at the current time.

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