BEGIN YOUR PROJECT BY SETTING UP YOUR FILE SYSTEM

I have been at several firms over the past twenty years that use CAD. There is always a situation wherein someone leaves the firm, and I have to take over his project and finish it up. Most times I spend a half day in figuring out what the predecessor did, then figuring out the little code of file names that person may have used. By far, the simplest way to leave a project and then get back on to it several months later is to set up the file structure using common sense terms. Also, having worked in an office environment, it is always pleasant to boot up your personal computer at 8:05 and find out Twinkle Fingers in room six has altered all your files overnight, and now the two of you do not know how to make things work as it did the afternoon before. In this way, you don't need a crib sheet for figuring out what has changed nor what those little drawing names mean.

If you are using Microsoft Explorer, File Manager, Xtree, or whatever, we need to create one file (or folder) in the most common place for you to reach CAD items. The simplest way to begin is to make a yet another directory attached or within the CAD program directory you so often use. If you are using Autocad, create a directory such as C:\ACAD\SPITFIRE It can be done in any of the above three utility programs, or by dropping to the DOS prompt, then finding the directory where the CAD files rest and do a MD SPITFIRE. Follow up with a DIR command, and you should find a newly created directory called SPITFIRE with zero in it. Do not copy or switch any of your CAD program executables into this directory (or folder). Most CAD programs can read/write/save to files outside theirown parent directory.

Putting most all your new CAD drawing files into this new directory branch becomes about the simplest place to find drawing files concerning this one project. The CAD directory gives the next guy a little clue as to where to find the project. A secondary item being is that whenever you need to pull up one of the drawings, it is the CAD named file/directory which is always at the top of a pull down window. The shorter the directory tree, the quicker you will be able to find the drawings. If you are experienced, you can also put all your correspondence and other non-cad files in this directory. Most CAD programs will not immediately identify files other than their own, so this secondary use does not interfere with your quick access to all the numerous drawing files to be used. Just as Windows will only highlight WORD compatible files when within a directory, your new CAD software will also only highlight drawing files. Then, down the road whenever a question is raised concerning some parts, some dimensional conflict, or an old letter created during some phase of the SPITFIRE project, you only need to go to one place to begin a search.

Don't get excited here in thinking you may choke up the CAD directory. The directory and files will only be active for the period you are on the project. After which, or after you are done, you can wholesale transfer the entire SPITFIRE job into another place on your hard drive. Then again, if you are on-again/off again working on a HELLCAT, this too can be added into the CAD directory, and not cause interference. Thus a year or two from now the CAD directory containing all the executables, will also have two, three, four sub-directories such as SPITFIRE, HELLCAT, PREDATOR

With hard drive failures becoming less often, you will undoubtedly read of or experience computers using two drives. The main hard drive will contain the Microsoft Operating System and the bulk of your programming and be labeled as C:\ drive. Then many home and office users like to incorporate a second hard drive which is labeled as D:\ drive. Those experienced computer users like to point out that in case of a power spike or an electrical storm, the D:\ drive seldom receives damage. The finished product which you are creating is much more vulnerable than the original software programming presently stored on a CD-ROM sitting safely in a desk drawer. The computer may go up in smoke, but at the end of the week you have the CAD software running again, but can you restore all the little drawing files as easy? Thus, if you are using two drives, with the parent CAD software loaded onto C:\ drive, you will need to establish a PATH so that it is easy to access the data saved on a different drive. Once you learn how to, it becomes second nature, and a safe way to store those time consuming drawing files. Microsoft Explorer will quickly and readily recognize the second hard drive within a minute after booting up the computer.

A point of warning. You do not know what the end recipient may need to do with your files. Keep the name short too. Less than eight letters or numerals is pretty standard. Yes, we know Microsoft will now permit long named directories, but can the end user read them? Also, if you are on the FILE32 system, there may be some question as to if the end user can use your output. Most generally they too must be on the FILE32 quick disk access system. This format has been generally accepted since about the introduction of Windows 95. You may be totally compatible within your own computer, but the object here is to be compatible with all those other computers too.

When you get going, I suggest you use the titles for parts which are already noted on the set of plans for the project instead of using some standardized title for everything. Thus if the project gets handed off to another person completely unfamiliar with the aircraft, or you get into telephone conversation concerning the plans, you have a visible and handy set of reference papers at your table top in which you can talk to them with. If the original draughtsman for the plans used "W" or "R" for all the parts to make up the ribs on the SPITFIRE plans, then use that title for the applicable parts. Your directory system will sort the order all out automatically. Whereas if the original draughtsman for the HELLCAT used "RIB", and that for the SPITFIRE it was "W" or "R", you should be using those titles for that particular project you are involved in, not some standardized system that was dreamed up.

In using the noted directory system, you can have one part C:\acad\hellcat\rib4.dwg and another in C:\acad\spitfire\rib4.dwg and not cause confusion on the hard drive. Likewise, the part C:\acad\spitfire\rib5.dwg, C:\acad\spitfire\rib5a.dwg and C:\acad\spitfire\rib6.dwg will each automatically fall in order when viewed in Windows Explorer. When your get going in making up all the individual drawing files, you will be repetitively placing them into the correctly named directory, not just one big huge filing system. However, often times I have found that plans will just list a part for a rib as being R4, and yet have a rudder part labeled as R4 also. You need to investigate this in advance, and assign non-similar titles to the parts. Otherwise, when you get around to making up the rudder parts, you may be wiping out all the work you did a few days ago in forming the rib parts. Depending upon your mood that day, just pencil in on the plans that rudder parts are named RUD6, RUD7, RUD8 and RUD8A. This will keep you away from interfering names and extensions.

A word of warning. Do not randomly number the parts being created. Numbered parts are confusing, unless the original draughtsman did it that way. Part number 10, 11, 12, 13 etc. will mean little to you a few weeks down the road on the project. Rud10, Rud11, Rud12, etc. will trigger the memory after a few weeks. Likewise, from nose to tail, or root to tip, do not randomly assign part numbers, even if that is the order in which you draft up the parts. You do not need to create part drawing files in consecutive order. If Rib6 looks to be easier to draw up at this time than Rib5, then do it. Again, the standard Microsoft file system will sort it all out automatically. However logically, Rib2, should be more towards the center than Rib3 is. If you come upon an un-numbered part, number it into a logical sequence like from the root rib towards the tip, of from nose towards tail.

Likewise I find all too often that on a constant chord wing the original draughtsman may draw on one rib, and then place a label on the plan stating it is "Similar, except as noted, for Ribs 3 through 8". For inventory purposes, although the rib has all the same interior and exterior lines, I assign a file name and number to each of those ribs. Thus in the end, a continuous series of ribs come out all neatly labeled 1 through 12. Not, 1 through 3, a gap in sequencing and then 9 through 12. Again, who knows other than you and the original draughtsman just how many Rib3 parts will be required for one kit. When the SPITFIRE directory is viewed in Windows Explorer, no gaps will appear in the file numbering sequence. In a week or so, maybe after vacation or holiday time, when your inventory is run, you will appreciate the simplified part numbering system.

Along a similar vein, I often see draughtsmen show one rib on the plan, but it is in two or three parts. You can handle this later as drawing the one part to begin with, but in the end you will be copying and breaking it down into sub-parts. It can be handled simpler in the format such as: Rib3, Rib3a, Rib3b, Rib3c, Rib3PLY, Rib3bPLY, etc. The parent drawing of Rib3 shows all the pieces, and the sub-set drawings show each on an individual need basis. Thus when you view the directory of SPITFIRE parts, you should automatically be able to determine that it takes more than one part to make up rib number three. Also, as most often left hand rib three is the same as the right hand rib three, you will in the end normally run two sets of parts to make up rib three as compared to running each side separately. Thus you don't need double the sets of parts drawn up.

Some of the plans designers like to take a balsa wood part and laminate on some thin plywood. Perhaps Rib3 needs to be made of 1/8" thick balsa and of 1/32" plywood. For this situation, I generally make up two part drawings. It helps at inventory time, and at cutting time too. At first glance, the parts of unidentical materials look to be the same, however there usually are minor line work differences involved. You may not remember two years down the road as to just why there are two very similar looking parts, but on the day you created them there was a real need. The second part will only take less than a minute to create, but months from now, it will take many minutes of thinking as to just why it exists. For the second part, like in the instance of a plywood lamination, I generally name the part Rib3P.dwg. The balsa part being Rib3.dwg.

Well, lets get bored with the project, or better yet finished with the SPITFIRE project. I create yet another directory within the ACAD directory called "OLDER" When a project goes dormant, the entirety of the directory gets transferred over to the OLDER directory on your hard drive. Use Explorer for this and it is done in seconds. When the SPITFIRE project needs to be revived, just transfer its entirety back to the active slot, and go. Thus when you are on to the MUSTANG project, which is long after the SPITFIRE project and the HELLCAT project and the FW-190 project are completed and in the can, they do not show up in your active directory window. I usually only leave a project such as SPITFIRE in the active window for only a month after its completion, then transfer it over to the OLDER directory and clear the window for faster identification and access. Give some thought to using zip compression software on those older projects to conserve hard disk space too.

One other thing ought to be brought up here too. That is suppose you are really a big fan of the Spitfire. You want to build a type II variant, a type VIIb variant, and maybe a type XXIII too. You are lucky and obtain a set of plans from England, all to the same scale, by the same designer etc. Number the variants as you wish, and create unique named file directories for the different parts. The designer may have changed a few fuselage formers, but incorporated the same parts and numbering from one of those earlier versions into his representation of a later variant. Just copy the unchanged parts over into the new directory, and you have saved yourself a few hours of work. Then all you have to do is add in the missing or different parts.

Just remember, that Rib3 in one variant has little to resemble with another variant. The home user has option as to title here. Think about using the title SPIT-23 or SPIT-7 as your main directories. Avoid using a title like SPITFIREXXIII, as it goes past that eight numeral file/directory figure in which you will need to copy and transfer to a laser cutting firm. It is also difficult to correctly keyboard in a series of similar numbers.

As an example here, many of the old Cleveland plans were done to one scale. If you obtain a catalogue, you will find your favorite in several scales or wingspans. These were often simply photographic reductions or enlargements of one basic plan. If you did the 1 inch scale version and now want to do the 2 inch scale version, just copy over the parts into a new directory, and begin the long process of re-scaling the individual drawing parts. Thus you have directories of C:/CAD/Condor1 and a C:/CAD/Condor2 which can later be edited into: C:/CAD/Condor/1 and into C:/CAD/Condor/2 and thus keep Condor as the main thought.

Yet another thing comes along here too. That is revisions, second thoughts, maybes, secondary or lets try this... designs. The basic end product is that you want to save what you have as it is OK, but again you want to try something else too. I had some laser cutting sheets of parts set up for a kit cut at one laser cutting firm. He could only handle up to 36" long sheets of wood initially. Later on I came upon a firm that had a machine which could handle 48" sheets. Via telephone with the customer, it was agreed to take advantage of the capabilities of the new firm. I had to re-sort all the parts with a line dividing the sheets into two 24 inch long sections for mailing purposes. Thus parts could cut in less over-all time, and save me some on the material costs. To keep work and not destroy my efforts, nor double or triple the hard disk storage space, a couple of directories were created within the drawing file directory. As an example under SPITFIRE you would make yet another single or set of directories. Title these with simple terms such as 24INCH, 36INCH, 48INCH or whatever you determine to be a simple named directory. If original parts were unchanged, and need no changes, leave them in the parent directory for the project. Put only oddball items into these sub-directories as the CAD system is smart enough to look into other directories for missing file names.

In Autocad by Autodesk, there is the capability to revise a single part and have that revision reflected in every-single-instance where that part shows up. Consider that in making up Rib3 for the five variants, you neglected to take into account a cap strip. Revise the parent Rib3 drawing, and if the file structure is properly set up, that one rib will then be correctly represented everytime in the future, and without initializing some revision command. But, more on this feature later.

Down the road the experienced CAD user will need to consider that of bringing in to your project or importing files created by another person or program. Most often these files will already have a unique name or extension that will not interfere with already developed individual drawing files. This variance in named file extensions will also enable the CAD program to only recognize the files (parts) which can be pulled into and be used by the program. If you have a airfoil or rib development program, after the creation of a rib, its output name and extension for your RIB4 could be Rib4.DXF or something similar. Likewise, if you are going the scanned image route (see Use of Aides) your parent image file could have a name like RIB4.TIF and thus there would not be any conflict with your creation of a drawing file using an extension such as DWG. If you are using Windows Explorer, just highlight the file name, then hit the PROPERTIES button and it will give you the whole name and extension. For older Windows 3.1 and XTREE users, the file extension names are readily shown.

The only problem exists when perhaps you and a friend across town are co-operatively creating all the drawing files. He may be doing the wings, and you are doing the fuselage and rudder. He may create all the required ribs using names such as R3.dwg, R4.DWG, R5.DWG etc. as shown on the plans. You at the same time are creating rudder parts with file names such as R3.DWG, R4.DWG, and R5.DWG. He gives you a disk or a download from the Internet, and when you pull up his parts, it will erase your parts at the same of the same title. You are then out maybe a dozen parts of effort. I find many times the program will automatically warn you that the directory contains that file title already. If you do a SAVE or SAVE AS watch for running the risk of overwriting, and destroying the earlier work. So watch out, or rename his or your files prior to importing.

This file swapping brings up a flaw to which maybe had not been considered. The flaw being that a good drawing file can be overwritten by a bad or obsolete one. This so often happens when you take a floppy disk to work which contains the raw ribs or fuselage files. During lunch hour you take advantage of the office CAD computer. Over the lunch hours of the week, you managed to fix up and draw only two or three parts. Progress, small but for sure. Then you take the disk home, insert it into the drive slot, and begin copying over those files. Instantly, Microsoft will tell you that another version of the same file title exists, and do you want to overwrite? As you just created all those new parts, why not say YES to the prompt. The problem here is that you need to take notes as to what files were actually changed. As you can easily open up a CAD drawing file, look at it, do no changes, but Microsoft will assign a later time/date stamp on it. Thus you may have twelve ribs on the floppy disk of which only two were altered at work, and five were altered on Thursday at home. The dates will not be identical anymore. Thus in this situation, it is always safer to open up the CAD program, and take a direct look at those twelve rib files resting on the floppy disk. You can then overwrite those originals to which improvements have been done during lunch hour. If you punch YES to all in Explorer on Friday, you will have ruined some of the work done in the evenings. Be careful, and don't trust the date always.

To recap what you will have created down the road. You should be able to drop to a DOS prompt and upon doing a DIR you should be able to see individual drawing files listed such as this:

C:/ACAD/SPITFIRE/RIB3.DWG

C:/ACAD/SPITFIRE/RUD2A.DWG

C:/ACAD/SPITFIRE/1-8.DWG

C:/ACAD/SPITFIRE/SHEET3.DWG