Model Boat Mayhem

Mess Deck: General Section => Chit-Chat => Topic started by: Brian60 on April 16, 2015, 07:45:41 pm

Title: A rescaling problem.
Post by: Brian60 on April 16, 2015, 07:45:41 pm
I have a downloaded pdf file of a plan of my next build. I opened it in Photoshop and changed display to full size and was shocked. The plan is 16 feet long :o my problem is there is no scale representation showing.

What I do have are several measurement shown on the plan, for instance space between frames is shown as12feet. So if I take a reading from the photoshop ruler to the same dimension of the frame width, ie say the ruler reads 2 inches between frames, we know the frames are 12 feet. So the scale would be 12ft to 2 inches- whatever that works out to.

Is it then just working out the difference between this scale and the scale I want to build ie 1/72nd and reduce the plans by that percentage?

I've been trying to get my head around this all day so help is appreciated.
Title: Re: A rescaling problem.
Post by: grendel on April 16, 2015, 07:56:09 pm
12 feet to 2" is 144:2 72:1 or 1/72nd so that would be what you want.
Grendel
Title: Re: A rescaling problem.
Post by: Brian60 on April 16, 2015, 08:03:49 pm
I just gave 2 inches as an example. when I look for sure its going to be something stupid like 1 and 19/32nds of an inch, you just know nothing is simple in this game  {-)
Title: Re: A rescaling problem.
Post by: grendel on April 16, 2015, 08:13:29 pm
just divide the 144 (inches) by the measurement (inches) and you will have the scale.
To get 1/72 scale you just need to scale whatever measurement you get to equal 2"
Grendel
Title: Re: A rescaling problem.
Post by: carlmt on April 16, 2015, 08:21:56 pm
Brian - If you would like, PM me your email address and I will do same.
Send me the pdf and I will re-scale it in autocad to 1:1 and then re-create pdf files of a smaller size (A1 or A0) to suit your 1:72 scale you want.  You would then be able to take them to a repro shop to have them printed out.
 
If this idea appeals, PM me.
Cheers
Carl
Title: Re: A rescaling problem.
Post by: Brian60 on April 17, 2015, 08:04:17 am
Thanks for the offer Carl. If I may take you up on the offer but delay it by 2 weeks until I have all my kit back in Spain? I'll send you a pm when I am set up again.
Title: Re: A rescaling problem.
Post by: carlmt on April 17, 2015, 09:33:01 am
OK Brian - no problem....let me know.
Title: Re: A rescaling problem.
Post by: Tug-Kenny RIP on April 17, 2015, 10:40:59 am

Sorry to interrupt the thread, but I'm building at this scale.

As an aside, can it therefore be assumed that 1:72 scale reduces a 6 foot length to down to  1 inch.  ?

cheers

ken
Title: Re: A rescaling problem.
Post by: vnkiwi on April 17, 2015, 10:50:03 am
Ken,
That's the maths that has worked for me for the whole of my working life, nearly 50 years, but now I'm retired the new maths may say different.
 :-)) %) :o
Title: Re: A rescaling problem.
Post by: grendel on April 17, 2015, 01:06:15 pm
yes, that is the whole basis of that scale 1" = 6 foot
Title: Re: A rescaling problem.
Post by: Brian60 on April 17, 2015, 01:13:57 pm
From what I can visibly see on this plan (without opening photoshop fully) it looks to be 19 feet between frames and using the inbuilt ruler the measurement is 5 and 3/8ths. So 5 and 3/8ths to 19ft.

Go on I double dare you to work that out for me %% PLEASE!!
Title: Re: A rescaling problem.
Post by: vnkiwi on April 17, 2015, 01:36:36 pm
I'd hazard a guess and say about 1 to 42.42,
give or take.
 :P

Next you'll be wanting the conversion ratio to 1 to 72.
 %%
so if my plastic brain is still working
=
a reduction of 0.589147286
or there abouts :-))

but, I have been known to be wrong, now and again.
 
Title: Re: A rescaling problem.
Post by: derekwarner on April 17, 2015, 01:43:33 pm
Brian..  :o..the batteries in my solar powered calculator appear flat, however the old Abacus suggests.......

19' x 12  = 228 inches
228" divided by 5 3/8" = the answer
228*5.375 = 42.42:1...however this is an imperial scale as the units were inches & parts thereof

Possibly my mate vnkiwi will offer to convert this to a metric scale which I suggest would be a bit less than 48:1, but a bit greater than 36:1 which are both well known metric scales  {-).....

It is also important to remember with you being in Spain, imperial scales are not appropriate for consideration as Spain has metric units....... ok2.........Derek
Title: Re: A rescaling problem.
Post by: Brian60 on April 17, 2015, 02:44:42 pm
Derek I'm not only english but also of the 'old school' or as the spanish are fond of saying, people of the third age (pensioners {-) ) I therefore measure big stuff in inches and small stuff in mm.
Title: Re: A rescaling problem.
Post by: Brian60 on April 17, 2015, 03:02:26 pm
Thanks guys. I got out the trusty calculator and it churned out a scale of 1/42.4 (possibly explained by the fact I converted imperial to mm overall before I did the scale conversion). For me thats close enough to your figures, so I'll go with vnkiwi's reduction guide!
Title: Re: A rescaling problem.
Post by: hammer on April 18, 2015, 08:43:21 pm
Brian, I understand you have a scale ruler for the plan. It don't matter what you call the spacing. ( inches meters chains fathoms or anything). Next make a scale rule to fit your model size, call them brains.  The frames will have to be drawn on the grid method. I have often built using this method, only 6ft models from 3ft plans, should be easier other way round. One tip mark the plan rule in red, to avoid confusion.
Title: Re: A rescaling problem.
Post by: BarryM on April 19, 2015, 09:18:55 am
Does this help http://jbwid.com/scalcalc.htm

Barry M
Title: Re: A rescaling problem.
Post by: Brian60 on April 19, 2015, 09:57:01 am
Had that nifty bit of software for a few years barry, it comes in useful, especially when you type the scale in rather than using the drop down list.

I think we have moved away from the original problem though,  --It is a plan without any scale on it. However it does have full size measurement marked on various points like between frames. To print out the plan as is would mean a plan of around 16 feet in length.

So taking the plan and the full size between frame measurement ie 12 feet, measuring that distance with a ruler in inches it came to 5 and 3/8ths of an inch. What would the conversion factor be to actually get the plan down from 16 feet in length to as it happens in my case 1/72nd scale- but that could equally be 1/100th, 1/144th etc etc.

That was the original question, and thanks to vnkiwi and derek I have near enough the answer. Then thanks to Carl who has kindly offered to resize the entire pdf file and reduce it to A0 sheets for me, although I can do that myself via photoshop and my laser printer, but the results would come out on many A4 sheets..