Pricing

Calculating the number of links in each coil type

To work out how much steel I needed to order for each piece, I needed to work out how many links I could get out of a metre of steel. 1 metre of steel is the longest I can safely wrap around the stakes to produce a coil. Having accounted for 10% wastage for manufacture, each coil length is actually 900mm. I divided the 900mm coil by the length of each link type to calculate the number of links per coil.

Calculating the material cost for the Shoulder piece

Referencing the cardboard model, I counted the number of each different sized links required and calculated the number of coils and metres of steel needed for the piece.

To calculate the material cost, I worked out how many coils I needed for each of the different link sizes using the calculations above. I then looked at 3 different online suppliers to get a range of quotes and found that there was a consistent problem with sourcing the 4 and 5mm mild steel rods that I use at University. This is because the suppliers only offer a higher quality cold rolled steel which is used in machining. For my application, the quality makes no difference and therefore the only impact is the increased cost.

I found that the company F.H. Brundle was the cheapest despite the additional shipping cost. The company is the only one which sells the steel in 3 and 6m lengths rather than 1m resulting in some excess stock. However, this could be used for testing and further projects. Additionally, I calculated the price for the copper clasp and found that Rapid Metals LMT was the cheapest option. To calculate the cost of the pieces I worked out both the total upfront cost and the price of how much I needed for each piece, using the latter for the final calculations.

Material cost = £50.14

Manufacturing plan for Shoulder piece

To understand the order and keep track of the different processes I needed to carry out to produce the Shoulder piece, I created a manufacturing flow chart. Additionally, this gave me the ability to cost out the timings associated with the different steps of the manufacturing process.

To make the 3 pieces, I decided to batch produce them, doing each manufacturing stage for all pieces at once. However, to record the time from start to finish would have resulted in an overall time cost for the 3 rather than individual pieces. Therefore, I worked out an average time for every manufacturing stage of each coil type. I can then use these averages to calculate the time cost for every piece by multiplying how many coils the piece requires. Additionally, this will allow me to work out the predicted overall time required ahead of manufacturing and better plan my work week.

Calculating the manufacturing time for the Shoulder piece

I calculated the manufacturing time by multiplying every stage by the required number of coils. I then added in the different set up and tidying up times for the processes. Also, I accounted for a 20min break for every 60mins of forging and de-burring as these are very labour intensive and I require rest periods

Calculating the cost of the the Shoulder piece

I first worked out the Time cost by multiplying the total hours by the hourly rate for a graduate of £27.08 as stated by the Artists' Union England. I then added this to the material cost for the total Item cost, which I multiplied by 2 for the Wholesale cost and again by 2 for a Gallery cost.

The gallery cost = £3341.84

Calculating the material cost for the Head piece

I repeated the same calculations to work out the rest of the pieces.