The index is a set of cards in six drawers in its own heavy steel cabinet. There is one card per drawing and information about who accessed them and when. These are known as ``drawing issue cards''. We have yet to fully analyse what this information might tell us. Unfortunately this is an incomplete record of withdrawals since, once a card was ``full'', it seems to have been replaced by a new one as noted on some of them.
The drawing issue cards in the Archive cover many other models in the Rootes range in addition to Imp and derivatives. This is however the only index we have and it was hitherto impossible to locate a drawing number from a text description of the part, although reference to the published parts lists helps for ``finished parts'' (see below). By having the drawing numbers and titles entered on computer, we aim to provide a searchable list and make it easier to locate individual drawings or sets pertaining to the manufacturing process and changes to specification over the 13 years of Imp manufacture. Actually the time period covered is more, as the first Imp drawing dates from July 1960 and the last from February 1977.
Drawings numbers are in two ranges, from 7100000 to 7106066 on the left hand side and 7200000 to 7291200 on the right hand side. Other part numbers are from the range of Rootes Company Limited standard parts which are catalogued separately in books now at the Rootes Archive Centre.
We have yet to fully understand the link between the system of numbering the drawings and the Parts List for the Imp Range. We note from inspection of the drawings themselves that the numbering is not simply chronological. Some of the numbers have also been changed from their original 7 digits to 8 digits. The prefix used also varies and is either `7', e.g. making 7212710 into 77212710. Others have an `S' indicating possibly a ``scheme'' which may or may not have gone into production, e.g. 7212960 becoming S7212960. We do not know what is implied by the 'A' or 'X' prefix.
Some of the index cards for the body panel drawings have another number which may be the Rootes Pressings number. This mostly follows a pattern, so 7201338 becomes 11500/0338 etc. This changes later so that 7202001 becomes 21500/0001 and 7203300 becomes 31500/0300 etc. However this conversion does not always work. This theory is confirmed by one card for drawing number 7202521 which states ND, master held at Linwood PSF 31500/0127.
There are other numbers on some cards, such as 20097400.500 on drg 77212826-7 or 201626.00 on drg 77212870. We do not know what these mean.
In working through the first drawing cabinet we tackled, number 40, Roger Swift and I noted that in some cases there are several different drawings for the same part. This pertains to the manufacturing process. For instance, for the early camshaft 7100000 there are casting drawings, a finished drawing and a drawing showing specification of the camshaft profile. The only number found in the parts list is the finished part number, 7100000, but the camshaft will be stamped with the number 7010103. Similarly the later Sport camshaft stamped with 7010157 is finished part number 7100423 which may cause some confusion. These are the casting numbers. There are similar sets of drawings for other cast or forged parts.
Because of the length of time it is taking to check and catalogue all the drawings based on the information drawn on them, we have decided to focus for a while on the index and note the drawing titles and numbers from these cards. Further information will be completed later and the information transferred to the second set of tables in Section 3.
The index cards also indicate the size of the drawing. They were originally labelled 1 to 4. Number 1 corresponds to approximately A4 size. Higher numbers have been re-marked ``Bin'' which indicates that they are in the full size cabinets. Once our listing is complete they will be moved to Section 3.