Wooden- This type of beam is structurally strong in tension and compression but does have weaknesses when it comes to shear forces. Generally it would not be sufficient as the wood would have to be made of probably oak and be very heavy to cope with the lifting of a tonne of material.
The cheapest price I was able to find was £30 per cubic foot less of VAT which means it would be very cheap but because of transport issues and also deterioratory issues it wouldn't be first option. I decided to go for manufacturer prices because trying to evaluate an estimate from raw wood market prices is frivolous.
Metallic - This is more of a realistic option as there are a wide range of materials available which are more expensive than wood but provide the strength requirements that wood, would not (excuse the pun). Generally a low carbon steel would be most ideal but the lower the carbon content the higher the prices generally goes because of the extraction process involved from the kind folks over at the blast furnace. I wasn't able to find exact prices on a fairly low carbon steel of our sort of sizing range but generally speaking (having to refer to market prices) it would be around £40-£60 per cubic foot minus of finishing previously mentioned in the post 'Finishing'. This would tend to add £8-£10 per. The extra price of this material and finish would pay countless dividends in extenuating the life of the crane itself.
For the less important parts of the crane, costs of the boom can be offset to these areas and materials costing less can be employed here. As long as strategic strength is not lost where it is needed, of course. Also, wood would have to be a custom made beam and the metallic beam could be of a standard size already mass produced driving down cost further.
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