bird-shots

I'm relativley new to RC...only been in it for a year now. I have successfully built several ARF's and a few large planes from kits. I have a lot of kits and rolled plans, but would like to draw and build semi-scale from 3 views. Being all electric, I feel that I can manage weight better doing it myself. Not to mention the satisfaction of knowing that "I did the whole thing" from scratch. I am half finished drawing an 82" electric TA-152 H from several 3 views and other images. Because I'm using DesignCad and Profili2, I don't mind printing out the plans and usinging them as templates to cut by, paper is cheap. However, that doesn't work too well with purchased roll plans.

I've heard of several ways to transfer the patterns to balsa; Acetone/burnishing (best method so far), tracing with carbon paper and scanning sections of the plans to produce templates. There are a lot of true "scratch builders" out there, and those that build from other's plans, surely some of you can share some tips and techniques on the subject. Any suggestions?

Thanks,

geach
[link=http://www.bird-shots.com]www.bird-shots.com[/link]

Ross Kean

Although I haven't tried it myself, I have seen photocopied plans transferred to sheet balsa using an iron. Apparently this will work with photocopied or laser printed plans. Won't work with ink-jet printing and may not work for commercial (regular ink) printing.

Ross

Kaos Rulz

bird-shots,

First thing I do when I get those rolled plans is take them to Office Depot, Kinko's, etc.. and copy them. I then use the copied plans to cut out whatever pattern I want to transfere to the balsa. If, for example, I'm cutting several ribs of the same size, I'll cut out the pattern and temp. glue it to the stack of balsa blanks. I like to use the kids' glue they use in school. It comes in a tube similiar to chap stick lip balm. I then cut the stack of ribs on the jig-saw following the glued on pattern from the copied plans. Sand out any irregularities, and presto, perfect parts ready to assemble.

Hope this helps in some way.

Steve Collins

My Feedback: (8)

I use mylar sheet to lay over the plans and trace the parts on the mylar. Cut the parts from the mylar with scissors and you have a template. Trace around the template onto the balsa for the outline of the part to be cut out.

CoosBayLumber

My Feedback: (1)

Several methods of doing this were discussed within the Scratch Building/CAD forum about two months ago.

Big discussion and arguments for this or that style. Search there and see what others think.


Wm.

bird-shots

Thanks all,

I tried the ironing thing, but it warped the balsa. What did work great was acetone/burnishing using photo paper instead of plain paper in a laser color printer...see [link=http://modelinghints.homestead.com/Patterns.html]Making Parts from Plans [/link] .

The attached image compares .35mm and .05mm lines. Don't plan on re-using the print, however, as most of the image is tranferred to the wood.

That pretty much takes care of my CAD plans, but will keep searching for the best method for rolled plan transfers.

Thanks again,

geach

bird-shots

Do you remember the thread title? I couldn't find it with the search.

Thanks,

geach

khodges

My Feedback: (1)

Was going to reply essentially same as steve collins-- I have access to old x-ray film--it is clear and a little stiffer than mylar. makes great pattern material

sina

I have done both the paper transfer with kids glue and mylar. I like the paper/ glue technique over mylar. To get the mylar right, I ended up using a drafting curve and ended up free handing several complex curves and drove myself crazy.

Regardless of how you do it, there is no substitute for rough cutting and then sanding the pieces into shape and using the plans to compare against. Remember to ditch those that "look close enough", they'll bite you in the you know what later!

Tip2: Glue some sand paper on say your spar for ribs and use it to cut your notch for the spar. You will get a tight fit that will hold the piece in place;let you align and then add a drop of thin CA to fix it.

Hey Ed, Is it just me do you notice that the kids glue tends to stretch the photocopy paper? Sometime, I swear my pieces come a little longer than the plan template!!!

bird-shots

Thanks everyone for their input and great suggestions. I like templates, till now thats all I've used to draw parts and pieces. That can be a lot of extra work though, and my template making skills are, lets say lacking. I did try something a little different this afternoon...before going to the flying field :-) I scanned a rib printed from my CAD program into Photoshop, then printed straight to my laser printer. I was a little shocked when I overlaid the print of the scan on the one printed directly from CAD. It was a perfect match...I mean perfect. I realize that when it comes to scanning, rolled plans are a pain to deal with, but with this option I will be able to use the Acetone/burnishing transfer method.

I still think there's a better, simpler and faster way...how about it?

geach

Xrod

My Feedback: (2)

Here's how I do it: Make copies of the plan if you like and lay this on the balsa to be cut. Trace around the outline with a pounce wheel to make an impression on the balsa. These are sold at sewing supply places. As an alternative use a modeling pin to make pin*****s through the pattern and into the wood. If needed you can mark the balsa with a pencil....connect the dots for better visibility. Seems time consuming, but when you consider the time to cut a pattern, glue it to balsa, wait to dry............. The glue seems to distort the pattern for me, and the pin***** method eliminates cutting around an outline for more accuracy. Try it!

Steve

sina

So what is this "Acetone/burnishing transfer method" anyway?

bird-shots

Thanks Steve, will do. I bought one of those wheels and some dress making carbon paper several months ago but never did try it. I like the pin idea better. I don't think my hand is fluid enough to use the wheel.

geach

bird-shots

Works great. This old timer, or should I say classic builder, knows his stuff... [link=http://modelinghints.homestead.com/Patterns.html]http://modelinghints.homestead.com/Patterns.html[/link]

geach

patternwannabee

My Feedback: (1)

Here's a different way.

I'm surprised no one has said this yet.

Using CAD, I print out the template on my inkjet (laser would probably work even better) using the thinnest lines possible.

Then I attach the paper template to the balsa or ply using spray adhesive. Use Repositionable spray. You don't want it to stick permanently.

Then rough cut the parts using a scroll saw, or bandsaw (bandsaw is best).

Lastly, I final sand using a disc sander. When done, peel off the paper (can be helped with the heat gun)

With the thin lines, you can get very accurate. I've done identical parts this way and when put one on top of the other, could not feel a difference in size.

bird-shots

Template to saw...sounds like a winner. At least its one less tracing to agonize through :-)

geach

Kaos Rulz

Sina,

I haven't noticed any stretching. If it's a large area to be glued, I only glue around the perimeter. If your's are coming out too long, that's better than too short, cause everytime you cut a short one - it'll still be too short. Sorry - couldn't help myself.

tucker1865

My Feedback: (6)

For wing ribs, where I need many of the same, I photocopy the rib, rubber cement to a piece of tempered hardboard (masonite), make a rib and then use this to form the ribs in balsa. Cut the ribs out with whatever you have, Scrollsaw, bandsaw, or by hand. I drill a couple of holes in the masonite pattern and wing ribs for holding and alignment and sand the ribs to shape, maybe 3 or 4 at a time with a disc sanber and a sanding block for final sanding. You dont want to sand the masonite pattern, just the balsa. The pattern will hold up a long time if you sand carefully. As for formers, I just rubber cement the xeroxed copy to the balsa and when finished peel it off, rub the cement residue off the balsa and done. Be carefull, some photocopy machines will not copy accurately. The Kinkos I use for large plans produces a copy slightly larger, like 50 inches becomes 50 1/2 inches on the copy. Use rubber cement to attach the large parts to the balsa. Last resort is carbon paper but this is very messy. If you rub a #2 pencil over the back, covering the lines with graphite it will act as carbon paper when you draw from the front side. Dave

sina

Man using Acetone still sounds messy[] Anyway, thank Bird-shots for the link though. A wealth of good information there. The trouble I find these days is that every generation has to "rediscover" these old tricks.

Ed, you're right. I always cut them longer and notch the trailing or leading edge. Provides for more gluing surface and avoids cutting them short!

Flypaper 2

I still use the old pin***** method. Straight lines need only pin ***** on each end. curves, cowls, canopys, etc. 1/4 to 1/2 in. apart depending on how tight the curve.

bird-shots

The acetone/burnishing from scans is time consuming...accurate but time consuming. I suppose a mix of methods is best, depending on the part.

geach

glommes

There used to be a marker in craft stores called a color blender. The marker is clear, has no color to it. I don't remember what brand it was I used though, I think it was about 3 dollars or so. Anyway, take your plans and get them copied from a CANNON copier. Don't know why, but it only worked with this particular copier. Then take the copy, place it ink side down on your wood, and trace it with the color blender marker. The ink from the marker will soak through the paper and you'll be able to see the lines you want to transfer to the wood. For best results, press the marker harder along those lines, but not so hard you leave dents in your wood. No need to let it dry.

bird-shots

Sounds very similar to the burnishing method I'm using. Its hard to believe how fast the acetone dries...doesn't affect the wood or paper. It isn't as messy as it sounds.

Heck, I'm almost to the point of building a small CNC machine and use CAD files to cut out ribs and such:-) It wouldn't have to handle more than 15 or so inches. Anyone have any recommendations on a CNC?

geach

apalsson

My Feedback: (1)

I simply use some cheap black carbon paper between the plans and the wood and trace the outline with a soft pencil.
Cheap and works every time. Not as messy as acetone and doesn't damage the plans