Trouble with plans..

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nightvision

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Hi everyone!
I'm working on to calculate the roughly cost of a single place wooden airplane to build. Because the cost is most important aspect of homebuilding for me:)
I have downloaded a minimax wooden airplane plan for free, thanks to team minimax:) Also I have bowers flybaby kit plan in PDF format.
So, I can draw anything with some CAD softwares (such as Autocad) for laser cut as long as I know what to draw. I just downloaded the plans to draw whole the airplane's wooden structure on PC to calculate the cost of whole wood structure (including laser cut).
BTW I work as a draftsman for a company, I draw cardboard packages for any products. We have a powerful laser cutting machine (Made for wood and sheet metal cutting) in the company. I can get a great discount for laser cutting from the company I think:) And the company has a plywood stock (5-6/9/12/15/18mm thickness) but I don't know whether they air aircraft quality. Anyway..
Besides, I don't have much time to work on building such a structure and I don't have a garage or something to work in and the only place which I could work is my friend's workplace and it's 110km away from my home. That means I have only weekends to work on it. Thats why I don't consider hand-cutting instead of laser-cutting.

So the problem is, I can't read the plans! I dont know how to read and comprehend those plans to draw it on Autocad. I'm looking the plan's pages and I can't visualise the parts!
How you guys read those plans:) I'm very begginner:)
 
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cvairwerks

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Try youtube for some videos on reading prints and how they are laid out. You are working in 2D now, so it isn't going to be too hard to go to understanding how a 2D drawing shows a 3D part. Think of it as unfolding your packaging and how it relates to what you draw for the cutter.
 

Aerowerx

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The Minimax plans include a bill of materials, which lists every piece of wood, plywood, and all the metal parts.

You should be able to use that to get a cost estimate.
 

TFF

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Unless they advertises aircraft ply, its not. The Flybaby was designed to use marine ply as an option. You will have to determine what they have by samples.

As for reading plans, it takes practice; visual practice in your mind. I can look at plans and see the 3D article in my head. It is just the language of building. 3D CAD is great, but the first steps is in your head. 3D CAD should what your brain sees by its self. To race to finish usually does not go well. Instead of taking the easy way out having it snap together with CAD made parts. Cutting out the parts by hand from reading the plans is how you teach your brain. Your short cut is why you are limiting yourself.
 

FritzW

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The MiniMax plans are a good place to start.

If the material call-outs are what's confusing you... Open the "Referance Sheet" page in a separate window so you can reference it easily. Then when your looking at the drawings and it calls for "RS-8" you can look it up easily.

Once you have an idea of what materials are being used all the drawings and assemblies will start to make sense.
 

nightvision

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The MiniMax plans are a good place to start.

If the material call-outs are what's confusing you... Open the "Referance Sheet" page in a separate window so you can reference it easily. Then when your looking at the drawings and it calls for "RS-8" you can look it up easily.

Once you have an idea of what materials are being used all the drawings and assemblies will start to make sense.
Ok now it makes sense:) I found and checked that reference sheet, its getting clear. Now I can see the individual parts of the structure.
I never worked with inches before and reading this plan is a little annoying but not that hard I think:) We use metric system in my country.
Thanks. I may have further questions:)
 

lr27

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Maybe looking at build logs and pictures like these will help:
https://www.teammini-max.com/aircraft/building-a-mini-max/

My set of downloaded HiMax plans includes a drawing labelled "1984 MINI-MAX" that shows an uncovered, partly cut-away Mini Max that might help. Do you have that file?

Someone somewhere probably has a 3D model.

Maybe you can build some of the smaller parts, like ribs, at home? Given the circumstances, it's probably a good idea to make your project relatively small, like the Mini Max. An even simpler project would be the Sky Pup. The landing gear is really simple and there's no bracing. The wing joining hardware is fairly simple, but the holes must be drilled exactly in the right positions. You'd need to solve your visualization problem first. Assuming the Mini Max plans are similar to the Hi Max plans, I think you'd find Sky Pup plans more confusing.

Maybe if you mock up some of the confusing parts in cheaper materials, like cardboard, things will make more sense. I'm skeptical that cutting by hand will teach you more, though. When you have a CAD cut part in your hand, it's pretty clear what the shape is.
 

nightvision

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Maybe looking at build logs and pictures like these will help:
https://www.teammini-max.com/aircraft/building-a-mini-max/

My set of downloaded HiMax plans includes a drawing labelled "1984 MINI-MAX" that shows an uncovered, partly cut-away Mini Max that might help. Do you have that file?

Someone somewhere probably has a 3D model.

Maybe you can build some of the smaller parts, like ribs, at home? Given the circumstances, it's probably a good idea to make your project relatively small, like the Mini Max. An even simpler project would be the Sky Pup. The landing gear is really simple and there's no bracing. The wing joining hardware is fairly simple, but the holes must be drilled exactly in the right positions. You'd need to solve your visualization problem first. Assuming the Mini Max plans are similar to the Hi Max plans, I think you'd find Sky Pup plans more confusing.

Maybe if you mock up some of the confusing parts in cheaper materials, like cardboard, things will make more sense. I'm skeptical that cutting by hand will teach you more, though. When you have a CAD cut part in your hand, it's pretty clear what the shape is.
Thank you for the answer.
Actually the problem was not about visualisation, but reading the plan. Once I can draw all the parts individually, it would not be hard to get them together.
Yes I can build some parts at home or at work but I still need to draw them to send laser machine to cut and estimate cost.

Fortunately I found the refence sheet and

I can build a scale model in cardboard but thats not the point. If I could see all the parts and their dimensions on the plan, its easy to draw by hand or CAD and cut them on cardboard or wood and get them together by referencing the plan.

Fortunately I saw the reference sheet thanks to answers on this post. I'll work on it again tomorrow at work:)
 

Jay Kempf

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Thank you for the answer.
Actually the problem was not about visualisation, but reading the plan. Once I can draw all the parts individually, it would not be hard to get them together.
Yes I can build some parts at home or at work but I still need to draw them to send laser machine to cut and estimate cost.

Fortunately I found the refence sheet and

I can build a scale model in cardboard but thats not the point. If I could see all the parts and their dimensions on the plan, its easy to draw by hand or CAD and cut them on cardboard or wood and get them together by referencing the plan.

Fortunately I saw the reference sheet thanks to answers on this post. I'll work on it again tomorrow at work:)
Don't worry about metric or inch. Just draw your CAD in drawing units and then you can always scale to whatever you need in the end.

Most plan sets are understood by looking at the assembly drawings first and there will be a numbering system that will have a symbol like a round circle (balloon) with a number or numbers in it that relate to the bill of materials. Then some have a key where the sheet number of the drawing relates to the part number and the balloon number. Once you figure that out it should be better to understand which parts are which. That lets you see a gusset even drawn in the assembly of other parts or a metal part on a wood part. Start with the bill of materials and look for item number or part number or some column labeled like that and then look for those same numbers in the individual drawing sheets.
 

lr27

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Converting feet and inches and fractional inches to metric. Or the other way. So much fun! Here in the USA, engineers have to do that all the time, at least if they're working with anything that came from other countries.

An RC flying student of mine once had a model with a 2-56 clevis over a 2mm thread on the elevator pushrod. By the time we got it down, it needed half up elevator just to fly level.
 

TFF

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If you are looking for some dimensions and they dont seem to be there in front of you, they are on a different sheet or different area of the drawing. There is not enough room to have all the dimensions every time on what you are looking at on printed paper. You have to find and or add some dimensions. When studying plans that is one of the things you make note of.
 

FritzW

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I'm sure you know this but don't convert anything. Just set "units" to imperial in your page preferences for the part. If the plans say 37 5/16" just type in 37 5/16. When your done drawing the part just turn it back to metric, the part will be 947.7375mm long. ...if your eyeballs and tablesaw are accurate down to nanometers your a better man than me :gig:

IMHO people make waaaaaay too big a deal out of units of measure.
 

autoreply

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I'm sure you know this but don't convert anything. Just set "units" to imperial in your page preferences for the part. If the plans say 37 5/16" just type in 37 5/16. When your done drawing the part just turn it back to metric, the part will be 947.7375mm long. ...if your eyeballs and tablesaw are accurate down to nanometers your a better man than me :gig:

IMHO people make waaaaaay too big a deal out of units of measure.
Replacing hardware is a mess. Fasteners, sheet thickness etc.

But you're right, stick to the original units. The risk and extra effort of converging them isn't worth it.
 

FritzW

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...just saying ...to no one in particular

If the plans call for an AN3-42 -no big deal- order an AN3-42 (and a -41 and -43 just in case ;)). Weather it's inches, millimeters, cubits or Klingon kellicam doesn't matter as long as you have the right tape measure. Don't over think it. Mark it, cut it, glue it in, paint it yellow and go flying.

And if you can't comprehend fractions how the hell do you split a pizza and a six pack with two friends? (splitting a pizza and a six pack with friends will come up, many times, during any build ;))

...sorry, repressed emotions from a long forgotten thread :gig:
 

MikePousson

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It took me a month of just looking at Roger Mann's version of the Parasol to even pretend to know where it was coming from. I could see it in 3D but nothing seemed to fit with a corresponding part. It all came together after a bit. That was my first experience with drawings. As far as cost of materials, wood or otherwise, be prepared to pay as you go. Buying everything upfront for Aircraft quality material will be a shock. Fuselage framework can be substituted with any good straight grain lighter weight lumber. It does not have to necessarily be Aircraft grade Spruce. Wing structure should be of the very best grade lumber and usually the plywood will be only Aircraft grade as they are usually the only kind that's available in the thin thicknesses you need to avoid weight. And they will cost and are only available thru Aircraft supply companies.
When you pull the trigger to build a plane, you are making a commitment to spend money. Someone, lots of it.
 
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