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#1 Shaper Dave Sep 27, 2011 06:56 PM

Arrow Ghost
 
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I have been absent for some time on this Group so decided to show a very small glimpse of what has been going on in my shop.

I had to stop all handlaunch production due to burnout and the need to move on to different projects. Those of you that did not get their new tails or whatever I apologize but I had to stop as time was running out for me to get to molding for Christmas time release of the P5 Thermal ship.

I have had the "Ghost" wing plug done for a long time and decided to mold it before I get to the 5 molds for the P5.
Right now every flat surface in my shop has parting trays and plugs sitting and waiting for their turn.

I thought it may be of interest to some of you how its done "old school" with out the use of a CNC cutter.

This is not a "How To" thread, but just a few shots of where I am at the moment. If you have questions I will be happy to answer them.

Dave

#2 DLGjunkyard Sep 27, 2011 07:05 PM

very nice. I would like to try that myself.
Is the plug just a foam core wing? Just how do you make a accurate plug without CNC?

#3 Wave Glider Sep 27, 2011 07:06 PM

Glad to see you back Dave! I've been waiting anxiously to see this apparition of a Ghost appear on camera :)

#4 The_Builder Sep 27, 2011 07:10 PM

Folks like Dave who work with their hands for a living and are accustomed to looking at how shapes will move through the water or air have no need for a CNC. There is nothing like a hand shaped wing.

Some folks just seem to have a natural ability to see things in certain ways.

Dave what did you do for a lay-up on the sacrificial wing? I have been trying to sell myself but just can't get there yet.

Paul

#5 glidermang Sep 27, 2011 07:27 PM

Dave:

You know I'm going to want one, when the time comes.

Good luck!

Yours, Greg

#6 LE PEW Sep 27, 2011 07:34 PM

Pardon my ignorance but what are the ball bearing keys? Do they align the mold halves?

#7 DLGjunkyard Sep 27, 2011 07:47 PM

Quote:

Originally Posted by LE PEW (Post 19439887)
Pardon my ignorance but what are the ball bearing keys? Do they align the mold halves?

yep.

#8 ThomasLee Sep 27, 2011 08:41 PM

Dave, thanks for sharing!
I'm also curious as to how an accurate mould can be done without CNC, I hope I'm not stepping on anyone's toes, but because me and a couple friends are working on a moulded project as well. Can a 'hand made' product really be as accurate as CNC as Paul suggests:confused:

Thomas

#9 Roy!! Sep 27, 2011 08:45 PM

Quote:

Originally Posted by ThomasLee (Post 19440521)
Dave, thanks for sharing!
I'm also curious as to how an accurate mould can be done without CNC, I hope I'm not stepping on anyone's toes, but because me and a couple friends are working on a moulded project as well. Can a 'hand made' product really be as accurate as CNC as Paul suggests:confused:

Thomas

id imagine its just like surfboards ya the cnc can be extremely accurate but most surfers are aware there is NOTHING wuite like the feel of a hand shaped board im sure its almost the same with dlg

#10 DLGjunkyard Sep 27, 2011 08:55 PM

Quote:

Originally Posted by ThomasLee (Post 19440521)
Dave, thanks for sharing!
I'm also curious as to how an accurate mould can be done without CNC, I hope I'm not stepping on anyone's toes, but because me and a couple friends are working on a moulded project as well. Can a 'hand made' product really be as accurate as CNC as Paul suggests:confused:

Thomas

not a chance,nope! I dont care how good your hands/eyes are. BUT that is not to say a hand done wing doesnt perform very well. specially if the cost is reduced.

having said that. even a coat of PVA reduces accuracy on a CNC plug

#11 Shaper Dave Sep 27, 2011 09:09 PM

It is quite possible to build a wing as accurately as a CNC. In fact you have much more freedom in small details you cant do with CNC. The only draw back is it takes lots of time to make the plug.

If your a hands on guy like me its a lot of fun and worth the effort.

The plug is a Blue Foam wing hot wired as usual but with a lot more sections than a standard wing. Hand finished and not done in a bag as per usual.

The core is done in a wet layup one side at a time.
I use the same carbon I use in the Arrows D tube at 0/90 top and bottom. then a 1.4 oz. finish cloth.

I have found that bagging actually deforms the surface more than you think.
Once its cured I fill with Duratec primer using a white base then the Grey as you see in the photos. This shows the high and low spots as needed.

I only sand these out to 600 grt. for final surface. There is no need to go any finer for the plug. All the final sanding is in the mold surface itself and you can go to 1000 grt. for that and compound and polish to finish.

Dave

#12 ThomasLee Sep 27, 2011 09:14 PM

Thanks for sharing Dave!! That sounds like a very neat way of doing it, I think a lot of guys without access to a CNC mill is going to appreciate you sharing your efforts and ingenuity!
Looking forward to progress in this thread :D

#13 Shaper Dave Sep 27, 2011 09:41 PM

I need to clarify some points on CNC cutting that most people do not understand.
I spent the better part of 12 years working on surfboards being cut by CNC machines. And I have been around a few different machines that have different capabilities.
The closer the cutting paths are together the better the finished product and the truer the finished item will be at the end. But, for most cases, you need to hand finish the mold surface to remove the tooling marks. This means sanding with different grit papers until the surface is where you want it and you have changed it, maybe as little as say, some PVA would do on a plug.

To have a completely machine finished surface lets say, in Aluminum is very cost prohibitive but would yield the most accurate wing.
When you have to sand the surface by hand your not really getting a better wing than a hand built wing, your getting a wing that took a lot less time and a lot more money.

Lets say you flew my new plane and it was the best thing you ever flew. Then I said the wing was designed in XFoil and CNC cut. You would naturally think WOW! high tech, thats got to be the secret and your satisfied and your world is in order.
Then your buddy who came to my shop for a visit tells you I did it all by hand with some templates and years of experience and I was pulling your chain for some fun! Would that plane still fly that well in your mind?

CNC's are great and I wish I could afford one for myself or had the patience to build my own but I don't.

Don't kid your self, you can make a molded wing that flys great without the computer. You just need a big can of Elbow Grease!

Dave

#14 Roy!! Sep 27, 2011 09:49 PM

Quote:

Originally Posted by Shaper Dave (Post 19441081)
I need to clarify some points on CNC cutting that most people do not understand.
I spent the better part of 12 years working on surfboards being cut by CNC machines. And I have been around a few different machines that have different capabilities.
The closer the cutting paths are together the better the finished product and the truer the finished item will be at the end. But, for most cases, you need to hand finish the mold surface to remove the tooling marks. This means sanding with different grit papers until the surface is where you want it and you have changed it, maybe as little as say, some PVA would do on a plug.

To have a completely machine finished surface lets say, in Aluminum is very cost prohibitive but would yield the most accurate wing.
When you have to sand the surface by hand your not really getting a better wing than a hand built wing, your getting a wing that took a lot less time and a lot more money.

Lets say you flew my new plane and it was the best thing you ever flew. Then I said the wing was designed in XFoil and CNC cut. You would naturally think WOW! high tech, thats got to be the secret and your satisfied and your world is in order.
Then your buddy who came to my shop for a visit tells you I did it all by hand with some templates and years of experience and I was pulling your chain for some fun! Would that plane still fly that well in your mind?

CNC's are great and I wish I could afford one for myself or had the patience to build my own but I don't.

Don't kid your self, you can make a molded wing that flys great without the computer. You just need a big can of Elbow Grease!

Dave

nothing like some hand shaped foam

#15 glidermang Sep 27, 2011 10:04 PM

Dave:

I will still want one.

Yours, Greg


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