Dumb question 101

[Maverick]

Hello everyone. I have a basic question, I have plans for a Thacher CX4 and I want to know how to I transfer the bulkhead drawings to wood ? I can't and don't want to cut the drawings up and have no idea how to transfer them. I'm

[rwanttaja]

Do the plans show the bulkheads against a grid? You can use the grid to re-create the drawing.
9515

Otherwise, find a roll of very thin paper, the original plans on a solid surface, lay the thin paper over it and trace the outline.

What size of drawings are we talking about?

Doing a Google search, I found several social media sites for the aircraft that might be able to give you some advice. There's also the "Thatcher Experimental Aircraft" Facebook page with almost 3,000 members.

Ron Wanttaja

[Maverick]

Great idea! Thank you.

[Maverick]

The plans have no grids unfortunately. They’re large, 16x20ish.

[DonN]

Take the drawings to FedEx/Kinko or equivalent and have copies of the drawings you want to transfer to wood made. Use the copies and keep the originals pristine.

[BJC]

Another method is to spread the drawings smoothly over a piece of poster board, then use a pin to prick through the drawing into the poster board. Do it in enough places to be able to connect the points smoothly. Cut the posted board, place it on the wood, and trace the outline.

You can also use varnish to adhere paper (not thick poster board) directly onto the wood, then use the pin prick method to transfer the shape directly to the wood.

I consider templates expendable, and would varnish the plans drawing directly to the wood.

Whatever you do, be sure to mark vertical and horizontal axes on the templates for transfer to the forms and the bulkheads for alignment.


BJC

[asport22]

Be careful trying to transfer parts drawings directly to parts. Copying machines don't always copy at exactly 100 percent of the original size. In addition, paper shrinks and swells with changes in humidity. Your plans are a copy of unknown accuracy - if you copy them, you may get a copy that is closer to true size, or farther away.

Measure the copy carefully before you use it to directly transfer dimensions to a part.

Plans suppliers often supply full size prints of wing ribs to save builders the task of laying out an accurate airfoil profile. Minor errors (a few percent) in the outline of the airfoil won't have a big effect on aircraft performance. However, on a metal aircraft like the Thatcher, if the ribs don't fit the spars correctly that can cause all sorts of problems.

Warren

[Maverick]

Thank you everyone for the input. I have a lot to ponder.

[mmarien]

You could use more modern methods than tracing or gluing paper to wood. I converted my ribs to digital (AutoCAD) and cut the jig and all the parts with CNC. I found a web page that plotted airfoils and started from there.

http://myhatz.blogspot.com/2016/09/march-2016.html
http://myhatz.blogspot.com/2016/04/april-2016.html


(http://myhatz.blogspot.com/2016/04/april-2016.html)

[vondeliusc]

Hello everyone. I have a basic question, I have plans for a Thacher CX4 and I want to know how to I transfer the bulkhead drawings to wood ? I can't and don't want to cut the drawings up and have no idea how to transfer them. I'm
A quick trick: get a clear Sterilite tote with a flat bottom from Wally World, turn it upside down, put an LED or light under it, and place your plans with tracing paper (with a grid?) over it, and trace it.