View Full Version : Project: Scale Model Building

08-18-2005, 05:33 PM
Good afternoon all,

I have a project that is just now in the design phase. I wanted to come in here and get some thoughts from you all before I get to far into this. Any help you have to offer is appreciated.

Goal: To build a 1/16th Scale model 'toy' farm implement.

Here is the project: http://www.berningauction.com/MVC-798F.JPG

As you can see, it should be simple to do. Here's the steps as I see them now.

1. Find the full scale version of this and measure/take pictures of everything.
2. Draw full scale plans (1/16th) to build from.
3. Determine materials and purchase them.
4. Build it.

OK, I've defined the goal, and set out steps to do this. I need help in step 2 and 3.

Roughly, this think will be about 18.75" wide given that the full scale version is ~25' wide. What I need help on is this. I need plans to build from. Should they be full size plans, meaning 1:1 of the model, or 1:16 of the full scale version? Should I draw a 1:16th plan set then convert that to 1:1? I'm thinking back to my model airplane days and what they did. They gave me 1:1 plans that fit the model, so I could build right on top of them. That is what I'd like to do here. What method or by what means would be best to draw these plans? I have a computer, but don't have "Auto CAD". Should I just draw them on paper and forget the computer idea?

Next question. The frame of the full scale version is a mixture of square tubing and rectangle tubing. Figure the largest parts of the frame at 5"x6" square and the rest at 3"x3" and 4"x4". Does anyone know if I could get 3/16"x3/16", 1/4"x1/4" square tubing? Maybe I should rather use 'key stock' or solid stock instead of tubing. I intend to gas weld the frame together. The goal is to make this model as accurate as possible to the full scale, down to working hydraulic cylinders.

Anyway, sorry for the long winded post..
This is my first shot at really doing something like this and thought here would be a perfect place to ask questions and post results as the project takes place. Remember, this is 'conception' phase...so any visible progress is still a few months away.

Thanks a lot!

Lynn Standish
08-18-2005, 06:04 PM
Can't tell from your post exactly where you are trying to go with the plans, but....

If you don't have AutoCad or similar, you'll probably need to do it by hand. 1/16 is not full scale. The actual original item is "full scale". I think what you are attempting to do is to make a model that is 1/16 the size of the real thing.

You will need to measure the original and make a drawing where all the dimensions are 1/16 of the real size. For example, if the real thing has a dimension that is 25'-0", you would need to use a dimension of 1/16 x 25'-0" on the drawing, i.e. 1/16 = .0625, so .0625 x 25' = 1.5625' = 18 3/4".

Another option might be to select a scale on an architect's scale that would work for you. They are different than above in that they are marked to allow various fractions or multiples of an inch to represent one foot. They have a triangular cross section, and each side of the triangle has four scales, so you can opt to have 1/6", 1", 3/32", 3/16", 1/8", 1/4", 1/2", and so on up to 3" equal a foot.

It may be easiest to use an architectural scale to make drawings of the original at whatever is a convenient scale and size, then take them to a blueprint company and have then enlarged by whatever % is needed to bring the enlarged copy to the actual size you want.

In AutoCad you can make your drawing to whatever decimal places you want within reason, and the drawing will be accurate to that number of decimal places. Drawing by hand, you won't be able to do much better than 1/100 of an inch, so you'd have to rely on calculated dimensions if you want something more accurate.

Hope that's of some use.

08-18-2005, 06:54 PM
www.micromark.com (http://www.micromark.com) sells small dimention tubing in round, and square. I haven't looked lately but they used to sell rectangle too. Most of it is brass so it would be easy to solder for "welded" joints.

Here's a link straight to the "metals" page.


08-18-2005, 07:02 PM
If I were doing this, I'd probably draw full-size AutoCAD drawings, then set the dimension scale factor to 1/16 before I did the dimensioning so the numbers in the dimensions would come out to the values I wanted for the 1/16 scale model.

There are some pretty good free CAD packages available for download -- search the archives for links to them. It may take you a while to learn how to use a CAD package, but once you do it is SO much easier than hand drawing.

Check www.smallparts.com (http://www.smallparts.com) for small square brass tubing. I doubt you'll find steel tubing that small. www.mcmaster.com (http://www.mcmaster.com) might have something.

One other thing to consider is the task of finding scale-size rubber tires. You ought to be able to find something in a toy store that will have appropriate-size tires you can cannibalize.

08-18-2005, 07:27 PM
Another source of small structural parts, and lots of misc. other neat stuff is:



08-18-2005, 07:29 PM
Hmmm, sorry about the double small parts thing, I swear that post wasn't there when I started out.

Tin Falcon
08-18-2005, 09:41 PM
Kansas Farmer:
If you draw plans 1/16 the size of the original that will be full size of the model or 1:1 at model size no further conversion. use the 3/4 to the foot scale on an archetects (SP) scale they should be available from staples etc. small brass tube round, square, and rectanular is available from K & S Engineering. Here is a link to a chart of sizes
http://www.ksmetals.com/Cuttolength/chart.asp and is sold at local hobby shops.
I would check into the posability of lego tires. Or if they ar all the same size you could find one you like and try to mold your own. Casting supplies from micromark or http://www.hobbycast.net/
Looks like lots of fun and work if you decide to make it stick to it and post some pics when you are done.

08-18-2005, 09:42 PM
<font face="Verdana, Arial" size="2">One other thing to consider is the task of finding scale-size rubber tires. You ought to be able to find something in a toy store that will have appropriate-size tires you can cannibalize.</font>

Look in the tire section of a hobby shop or catalog. Airplane and car tires come in sizes from about 1/4" all the way up to 4". Different tread designs are available too. Wheels are also available, if you don't want to make them.

08-19-2005, 12:03 AM
Kansas Farmer... Here some inspiration. This guy does some amazing work.Don Campbell (http://www.doncampbellmodels.com/index.html)

08-19-2005, 12:31 AM
Hey all,

Thanks for all the cool ideas!! That Don Cambell is one heck of a good builder! Interesting reading there!

Now, to find some time to get all this stuff done....!

08-19-2005, 05:01 AM
From that Don Campbell page:

"I wished I could make them look more perfect but without a lathe and a milling machine it's hard to make many of the parts."


08-19-2005, 06:19 AM
bikepete, that's a humbling line isn't it? that combined with how much stuff he's built, wow.

Your Old Dog
08-19-2005, 06:32 AM
Kansas, if you haven't already, go to any hobby shop and check out the materials they have on hand before ordering from out of state. You will not only find much of what you need but some stuff you didn't know you needed ! good luck.

08-19-2005, 07:49 AM
bikepete: Don't you just hate people like that? http://bbs.homeshopmachinist.net//smile.gif

08-19-2005, 08:45 AM
Kansas Farmer, have a look at this lot and if you think that I can help in any way,


just let me know and I'll get back to you.

08-19-2005, 10:28 AM
<font face="Verdana, Arial" size="2">Originally posted by radish1us:
Kansas Farmer, have a look at this lot and if you think that I can help in any way,


just let me know and I'll get back to you.</font>

WOW! Nice detail there! Only one thing wrong with it. The steering wheels on the wrong bloody side of the cab! :P J/K

It'll be a while before I can do that kind of work. I picked a farm implement as a project because I wanted one and it's simple enough for a beginner like me to do without too much frustration.

I have to get my iron rack built, then get the engine overhauled/replaced in my pickup before I can get started on this model job. I'm thinking that this is going to be a winter project really.

As far as tires go, that part is solved. A place called Dakota Toys has all the wheels and tires I'd ever need for farm equipment. This kind of stuff is what they do.

Paul Alciatore
08-19-2005, 11:27 AM
If I were doing it, I would consider CAD a must. If you don't use it already, FORGET AutoCAD. It will take you longer to learn it than to build the model. I use FastCAD which is easy to learn and they have a 30 day free trial. www.fastcad.com (http://www.fastcad.com)

As to the scale, one wonderful thing about working with CAD is that you can change the size/scale at will. You can draw it "full size" in the computer and it does not take a drawing table the size of your living room. Once the full size drawing is done you have several options. You can use a simple Scale command to change it by any factor. If you have already added dimensions, the dimensions will automatically change also. Neat, ha?

Another thing is that the prints can be scaled. Thus you can have a full size drawing for your 1/16 scale model and then print it in smaller or larger scales. In this case, the dimensions will not change so you still have the correct numbers for what you are doing.

CAD is great.

For square tubing check out hobby shops - the kind with planes and boats and model RR stuff, not women's hobbies. I can't remember the brand name but there is a company that makes brass structural shapes in scale sizes. They should have wheels also.

Paul A.

08-19-2005, 11:41 AM
CAD? From Don Campbell's page: "I look at a few pictures as guidelines, but because I use no measurements on most of my metal creations, I must have some artistic ability."

08-19-2005, 11:59 PM
For square or round brass tubing,look for the "K&S"brand.Also useful is "Plastruct",they make (made?)many different profiles in ABS plastic or styrene.


Tin Falcon
08-20-2005, 02:50 PM
K F:
Another couple of thoughts. I you have a set of drawings the full size of the prints you can lay the parts right on top of the print to build. An old airplane building trick is to lay out the parts on a piece of wax paper layed over the print. the other way would be to make a wood jig to hold the parts in place for intial soldering. (Not torch soldering) also the K & S folks have tube that will fit one size into another so long pieces can be easily made from short ones K & S usualy sells in on foot lengths.

Paul Alciatore
08-20-2005, 05:56 PM
<font face="Verdana, Arial" size="2">Originally posted by matador:
For square or round brass tubing,look for the "K&S"brand.Also useful is "Plastruct",they make (made?)many different profiles in ABS plastic or styrene.

"K&S", that's the brand I couldn't think of. Thanks matador.

Paul A.

08-22-2005, 01:01 AM
Thanks guys!!

I'm going to start taking some pictures and getting measurements now. Then draw out a bunch of plans. I guess I'll just do the plans for the model, scaling everything as I draw it, so I can build 'on top' the plans as it were.

Now, all I have to do is find me a machine and get started.

08-22-2005, 02:10 AM
Hi Kansas, the first thing to do, is get hold of the tyres and get an accurate measurement from them.
This will determine the actual scale of the completed model.
When you know exactly what scale you are building, draw ALL the parts to that scale size and you then make everything, direct from the drawings.
Here is a link to K & S, have a look thru this site and you'll see what bits are available. By using brass for the frame, you can use soft lead solder or use silver solder to hold it all together.


Get ready for a headache and for all your friends to call you a nutter, but you will have fun doing it tho'.

08-22-2005, 09:28 AM
I already know the Scale, it's 1/16th. The reason is that is what all the other 'toys' are and this needs to be of the same scale so it looks right behind a commercially availalbe 1/16th Deere 4430 from Ertl.

I notice most people say to use Brass. That's cool, can do. One question though. How well does Brass hold paint? What if any special tricks do I need to use to make it paint better?

Thanks again!

08-22-2005, 12:02 PM

brass holds paint fairly well, just go back about 40 years before your 4430 was made and check out the painted brass carbs on the original Deeres. http://bbs.homeshopmachinist.net//smile.gif

just give the brass a good scuffing and paint as normal.

make sure to post pics once you get going!!!!

andy b.

08-22-2005, 12:46 PM
Yea, Andy, now that ya mention that, I "knew" that...

Getting forgetful in my old age I guess...

Anyway, I'd still prefer steel or iron in the construction as opposed to brass, mainly for looks. What I mean is, once I build a few of these, the one I keep I want to paint up nice, then bead blast it slightly, knock some of the paint off of it, then hit it with a water hose and a mild acid. That'll rust it where the paint came off. I can't have 'new' equipment!! Brass won't 'rust' and I don't feel like 'painting on rust' later, as I just can't get the same 'realistic' effect.

So, with that in mind, I'll go looking for steel first, if I absolutely can not find that I"ll go brass..

08-22-2005, 07:31 PM
As the equipment is of current manufacture, you might contact the maker. Tell them what you're up to! They might be willing to help out with the plans or dimensions; in exchange you might make two models and send them one. Sometimes things work out pretty neat that way. They could tell you no, or not answer, but what the heck, it's worth a try. Full size plans? Not even the equipment maker would mess with that; it'll be scaled, maybe even what you're looking for...

08-23-2005, 03:27 AM
Hi Kansas, you're ideas of having the rust look realistic on the model has been kicked around by modelers for many, many years.
The conclusion that dozens and dozens of highly skilled modelerers have arrived at, is that you can make a model to scale, but you sure can't tell the rust to stay to scale.
Make a 1/16th scale model from STEEL and then deliberately make it rust, is just asking for a tragedy, when the rust just keeps-on-a-rustin'.
In a couple of years you will have a good looking model of -- RUST.
Think about why modellers use brass and then just add the rust effects by cautious use of rust coloured paint, you can get that from the model railroaders, mixed with a bit of dry Bicarb of Soda powder to give it that true to scale look of rust.
Talk to quite a few modellers before you go ahead and make the model from steel, the more ideas you can get hold of, will sure make life easier for you.

08-23-2005, 09:40 AM
Yea, I suppose you're right. Hadn't thought that rust problem completely through...