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Scott Parks
12-20-2004, 4:00 PM
I haven't actively used AutoCad for about 10 years... Trying to re-teach myself.

Anyway, does anyone have a solution or tips when designing casework or cabinets using undersized plywood? Not sure exactly what I'm trying to explain here, but for example: If assuming plywood is exacltly 3/4" in Autocad, but you use 23/32 ply for actual construction, by the time you use 4 panels accross an axis, you are 1/8" off. (Hope that made sense). But on the flip side, If you draw assuming 23/32", setting your snap to 1/32 increments is a pain. Also, I'm not patient enough to make calculations to 1/32". What techniques do the Pros use? Is there an easy compromise? Maybe I'm making this too hard.

Is autocad still the industry standard for drafting?
Any other general tips? Thanks...

Randy Meijer
12-20-2004, 5:33 PM
Is autocad still the industry standard for drafting.....
Guess it depends upon what industry you are talking about; but yes, Autocad is still probably the standard by which other drafting programs are measured. Don't how much response you are going to get here?? A full bore version of Autocad is in the vicinity of $4-5 k so your average home craftsman isn't using it. There are quite a few "home" drafting programs available that are reasonably priced and maybe one of those would be more useful to you??

I am a casual Autocad user.....took a couple of courses at the local community college and use it at work on occasion.....not a full time drafter. Having never drawn plans for cabinets, so I may not fully understand your difficulties; but I will offer a couple of thoughts. First off, if you want your furniture accurate to a 32nd, your plans are going to have to be that accurate. There are no short cuts.....so do try to be a bit more patient.

Using the offset command should solve a lot of your problems. Draw one edge of your panel whereever you need it, then offset 23/32" and you will have a perfect width with no calculations.

Another thing I find useful is to make up some standard sizes and shapes and then copy them where needed. If you make up a 23/32 x ??? shape (both a horizontal and a vertical) you can pop that whereever you need it and then use either a trim or an extend depending on your need. Maybe the above are things you already know......if so, I apologize for the repetition. It's hard to know how familiar you are with the program.

Do consider visiting your local community college and taking a basic Autocad course......may be just the thing???

Keith Cope
12-20-2004, 7:09 PM
Scott,
I agree with Randy, you will get a lot of mileage using the offset command. You may want to consider turning SNAP off, and using direct entry lines and OSNAPS. When you draw a line, start at one end and instead of clicking for the other end, you can type in the distance and direction. For instance, a 2' horizontal line would be '@24<0'. From there, using OSNAPs you can start a new line directly at the end or the midpoint, etc. It's pretty hard to give an AutoCAD tutorial in a forum, I'd recommend buying an aftermarket user's guide for the version you are using. Hope this helps, you can PM me for specific questions, etc. if you'd like.

Keith

Randy Meijer
12-21-2004, 1:12 AM
Scott:

I use Autocad R14 for land surveying so I've been fooling with some of the other "units" options and maybe the following will be of help to you. If you select the units command and select either the architectural or fractional option(with a precision of 1/32), you can input your dimensions to a 32nd without converting from decimals. If you select the architectural units, you will be working in feet, inches and 32nds and the entry format will look like this: 2'6-23/32" and the output will show 2'-6 23/32". If you select the fractional option you will be working in inches and 32nds. The entry format will be 50-23/32 and the output will be 50 23/32. Note that you need ' &" symbols in the architectural option but nothing in the fraction option.

Hope this will be of some help!!

P.S. You can find the units option in the format pull-down menu or you can enter the command directly.....ddunits.

Kirk (KC) Constable
12-25-2004, 6:41 AM
You can enter your dimensions either as feet/inches/fractions or just inches/fractions...the display will be the same as whatever you have dimunit set to (dimunit=4 displays feet/inches/fractions). I enter the distance whichever way is more convenient at the moment. AutoCAD is pretty smart. :-)

KC

Todd Burch
12-25-2004, 11:40 AM
Scott, I don't use AutoCad, and I'm not going to force feed you with what I do use, but here is the technique that I use when drawing.

First, I'll state that in my construction drawings, a human will be doing the cutting and fitting and assembly. If I were drawing for CNC output, it would probably still work just as well, but the reference surfaces might have to change from what is usually used. (I don't know enough about CNC setup to say.)

If I want a cabinet 3' wide with a dadoed bottom shelf and top shelf, I draw the cabinet 3' wide, using 3/4" for the plywood sides and shelves, and draw my dados 3/8" deep by 3/4" wide - just as you would in a perfect world where thicknesses were as stated.

So, in my drawings, my shelves are 3/4" shorter than my cabinet is wide. When I go to cut the shelves, I cut them as exactly in my drawing. When I cut the dados in he case sides, I cut them so that 3/8" material is left behind the dado. The dado depth is something less than 3/8", but this way, I never care how thick the material is (except when setting my dado blade height, but that's a scrap piece action anyways), and my outside case dimension is not affected, and I'm not (typically) having to mess with distances in odd fractions (unless the case width is an odd fraction to start with).

For the next step, a face frame, I key off outside case dimensions again. That way, if my face frame part widths are not perfect - doesn't matter, I'll adjust the doors or drawers when I get there.

For doors (or drawers), I always make them the same size as the opening, or just a bit proud actually, and then trim them to fit (I mostly make inset doors - overlay doesn't matter how off they are). When I trim to fit, any offsets that occured during the glue up of the, for instance, top rail to stile, are trimmed off while fitting the door. As an example, in my drawings, door rails and stiles are 2 1/4" wide. When I machine them, I leave them 2 5/16" wide and cut my stiles 1/8" longer than the drawing. I cut my rails just as in the drawing. My panels are also cut just as in the drawing.

Hoefully, I was clear in the description of what I do. Todd

Scott Parks
12-25-2004, 2:40 PM
Thanks for the tips...

I think I'm trying too hard. I should just stick with 3/4 units to keep it simple, and do what Tood does, and adjust to fit. Trying to draw to 1/32 is too time consuming for me. Close enough for government work. Todd, that makes sense on leaving 3/8 behind the dado/rabbet. I was trying to plan with a 3/8 deep dados, and rabbets, thus making errors in the end product. Sometimes it is so simple, yet I don't see the solution. Thanks...