Allen mogul plans and "scaling"

[Steven E. Kuhn]

I'll go with the ubiquitous Kinkos. Maybe the blue print shops are less. But when the closest one to me is is 25 miles and Kinkos is a mile away...and gas is $4.25 per gallon.....kindaofa no brainer. Besides with Kinkos I just want a fast copy and I get to play with the machines myself. Instead of telling somebody what I want and standing there with my thumb up my *** waiting as he does it the way I don't want it.... Anyway depends what you are looking for. I've taken drawings out of books and come up with some nice detail by blowing them up. Detail you couldn't see in the book. I can play with the machines all I want. Blow it up 125% or 500% whatever.

Good luck,
Steve Kuhn

[gwrdriver]

Funny, I've had EXACTLY that same experience with Kinkos . . . they really are clueless when it come to large format reproduction.

[Mike Walsh]

I'll go with the ubiquitous Kinkos. Maybe the blue print shops are less. But when the closest one to me is is 25 miles and Kinkos is a mile away...and gas is $4.25 per gallon.....kindaofa no brainer. Besides with Kinkos I just want a fast copy and I get to play with the machines myself. Instead of telling somebody what I want and standing there with my thumb up my *** waiting as he does it the way I don't want it.... Anyway depends what you are looking for. I've taken drawings out of books and come up with some nice detail by blowing them up. Detail you couldn't see in the book. I can play with the machines all I want. Blow it up 125% or 500% whatever.

Good luck,
Steve Kuhn

careful what you say..

they quoted $6.00 per sheet for copies, and a whopping $40 per sheet for scanning!!!

I said 'see you later'

It's much cheaper to draw them up myself and have a hard copy.

mike

[Fender]

Agreed that some people won't have a blueprint shop nearby. I did (fortunately) and took my 30" X 72" loco drawings to be copied, which cost about $5 each. What a bargain! And if the scale isn't right, they were willing to experiment with different reduction/enlargement at a different percentage (several times) and only charged for the final version...
By the way, while I agree that it isn't good practice to scale a drawing, if the prototype doesn't exist anymore, and all you have is the prototype erection drawing, that's a lot better than starting with a photograph

[FLtenwheeler]

I have purchased over 100 original drawings (copies) after I received them I took them to a Blueprint shop and had them scanned to TIFF files. I made a CD and sent it to a friend for safekeeping. I have the paper copies and TIFF files. The blueprint shop keeps a backup copy of the TIFF files also.

As to scaling: I have imported the files into my CAD program. Some are perfect and some are not anyway close to being to scale. I do a lot of CAD drawing over the picture of the original drawings. It helps make things go faster when it works.

I have stared to do 3D drawings of the Cole trailing truck parts and hope to send them out to be RPed by the end of the year. I have 20 drawings just for the early Cole trailing truck. That is all of them except for the brass and 2 or 3 other parts inside the journal box.

Tim

[LivingLegend]

Tim:

What was the cost (per sheet/size) to scan your original drawings?

LL

[Bill Wilkins]

Ben, here is my 2 cents.
Find a piece of 1/4" ply or masoinite or something 24" x 66" and lay it on something flat like a desk top on the other side of the shop away from the work area. You now can open the plans up and let it lay open at the page you want. I can't tell you how many times I have flipped through the pages looking for that "other part". Sometime I would half fold a page (no crease) just to look at two pages at the same time.
Don't take measurments off the plans with the calipers or with the ruler. Use the numbers printed. Don't set your coffee cup on the plans, don't paint your last part made on them, don't lay them next to an open window during a thunderstorm !!! Lay a piece of visqueen on them when not in use. I did not make copies, I just took care of my plans.
I would take a piece of scrap paper and sketch the part on it and write down all of the pertinent, applicable measurements and I would make my part from that piece of paper. Always double checking the numbers I had wrote down before hand. This will minimize your trips back and forth to the drawing board.
Use a dedicated light overhead for the plans.

Good Luck, Bill W. (from the Allen Group)

[FLtenwheeler]

Tim:

What was the cost (per sheet/size) to scan your original drawings?

LL

Hi

It is $4.00 to $6.00 dependent on size. They will do TIFF or PDF format.

Tim

[Steven E. Kuhn]

Careful what I say. I didn't say scan a barn. I'll stick with Kinkos.

[Steven E. Kuhn]

careful what you say..

they quoted $6.00 per sheet for copies, and a whopping $40 per sheet for scanning!!!

I said 'see you later'

It's much cheaper to draw them up myself and have a hard copy.

mike

[Kimball McGinley]

In the 1970's my college Drafting teacher told me that when he worked at GE, he was getting bad parts, and believed that the sheet metal shop was scaling his drawings. His boss disagreed saying "They know not to do that."

Finally, he sent them a drawing that was carefully marked "Do not Scale Drawing", and also marked "Scale: 7/8."

You guessed it - he got back a 7/8 scale part! Busted!!!!

[Curtis_F]

I’ve spent thousands of hours, professionally and personally, making CAD drawings from prints that are not fully dimensioned or not dimensioned at all. The tools of the trade are; Calipers, note pad, calculator, a little common sense, and a taste for humble pie. Of course numbers on the drawings take precedence, but a fully dimensioned drawing is a luxury we seldom have.

Like Tim said, some drawings are wonderfully drawing and everything scales out dead-nuts-on, and others have been revised without the draftsman taking the time to redraw the lines, or they just made it look good on paper regardless of accuracy.

Take measurements off labeled dimensions on the drawings with calipers and use a calculator (or create a spreadsheet in Excel) to find the scale, and then compare it to other labeled dimensions on the drawing. It’ll be quickly apparent how accurate the drawing is, or I should say, how accurate the draftsman was.

It’s actually like doing calculations in Astronomy. The final answer you get has to be round off to match your worst measurement. That is to say you can work with a dozen factors that go to eight or ten decimal places, but if you have one number that only has one decimal place, then you round your final answer to a single decimal place.

And the greater the distance measured the greater the accumulated error is likely to be.

When you measure a blueprint with calipers you get three decimal places, but when you work it through the drawings scale you have to round off to the nearest fraction. Depending on how consistent the measurements are will tell you if you have to round to the nearest inch or to the nearest 32nd of an inch.

I have seen Baldwin blueprints that you can measure a couple of dimensions to determine the scale of the drawing to three decimal places and everything scales perfectly to a 8th inch fraction number. Others…it’s a matter of your best guess.

Many times I’ve even found the official blueprint do not match the parts made. Patternmakers sometimes had to change things in the pattern shop to make the parts pour correctly, and sometimes the erecting shop crew had to make adjustments to make the parts fit.

Blueprints are not the official word of what the parts were like.

They’re a good starting point, but you need photographs to back up your work. Like David S. on his K4. He has prints, but he has lots of prototype photos as well to see what the parts actually looked like.

The longer I do modeling I find it’s more important to have the part look right than it is to have the part be “to the print.” As Jack B. likes to say, sometimes you just gotta’ stick out your thumb.

In conclusion (if you’ve read this far) is that there is nothing wrong with scaling off prints so long as you pay attention and think about the answers you’re getting.


Cheers,

Curtis F.