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Old Oct 17, 2008, 12:10 PM
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Sabrejock's Avatar
Winnipeg, MB Canada
Joined Jan 2000
2,419 Posts
Quote:
Originally Posted by jfetter
DAG,

You are correct about the Battery-to-ESC leads BUT you can extend the ESC-to-Motor leads considerably. I've extended them 36" in pushers before without issue (make sure they are even) and I've heard others that have extended them more...

Jack
And you can add another couple of good size capacitors at the input side of the ESC, just like the ones that are already there. I do this with large twins that have the batt in the fuse. I really don't know when they become needed, but I did it as a safety factor. Tex.
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Old Oct 17, 2008, 03:12 PM
It only takes one good idea
dag214's Avatar
Fishers, Indiana
Joined Oct 2004
6,017 Posts
Quote:
Originally Posted by jfetter
DAG,

You are correct about the Battery-to-ESC leads BUT you can extend the ESC-to-Motor leads considerably. I've extended them 36" in pushers before without issue (make sure they are even) and I've heard others that have extended them more...

Jack
jfetter,
What amp ESC were you using, what size motor. I was told by Castle not to go more than 12" from battery to motor. If I can go more then I will move all my Lipo's to the front center of the wing with the ESC close by then run wire out to the motors. I may have to test to make sure it will work.

Thanks, DAG
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Old Oct 17, 2008, 03:15 PM
It only takes one good idea
dag214's Avatar
Fishers, Indiana
Joined Oct 2004
6,017 Posts
Quote:
Originally Posted by Sabrejock
And you can add another couple of good size capacitors at the input side of the ESC, just like the ones that are already there. I do this with large twins that have the batt in the fuse. I really don't know when they become needed, but I did it as a safety factor. Tex.
Tex,
Castle said that I needed to add the same size capacitor that is one the ESC for every 1" that I go past 18", now others have told me that it is 1 capacitor for every 6". But if I can add on the motor size that would help a bunch.

Thanks, DAG
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Old Oct 17, 2008, 03:18 PM
It only takes one good idea
dag214's Avatar
Fishers, Indiana
Joined Oct 2004
6,017 Posts
Well here is the first Rib (really Rib#2, but the first one cut).

It is only 1.5oz, which is .5 heavier than I had wanted.

I am using my V.P. of develpment (Emma) in the pic for scale.

This is really going to be a cool project.

DAG
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Old Oct 17, 2008, 03:23 PM
Bi-Planes
Tim Farrar's Avatar
Houston Texas
Joined Apr 2006
1,589 Posts
Quote:
Originally Posted by dag214
Well here is the first Rib (really Rib#2, but the first one cut).

I am using my V.P. of develpment (Emma) in the pic for scale.

This is really going to be a cool project.

DAG
Wow that is really huge !!!!

I cant imagin how this will look when finnished !!!

The VP there must be doing a great job because she is the same as the one for your last build !!..lol...


Seeya, Tim
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Old Oct 17, 2008, 04:01 PM
Put a bigger motor on it!
gtfreeflyer's Avatar
Costa Mesa, CA
Joined Feb 2007
1,443 Posts
How do you cut the rib? Do you print out the shape full scale and then trace it onto the rib? Do you then just carefully cut it manually with your router? What's the trick to getting it exact?
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Old Oct 17, 2008, 04:23 PM
It only takes one good idea
dag214's Avatar
Fishers, Indiana
Joined Oct 2004
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Quote:
Originally Posted by gtfreeflyer
How do you cut the rib? Do you print out the shape full scale and then trace it onto the rib? Do you then just carefully cut it manually with your router? What's the trick to getting it exact?
gtfreeflyer,

I will take some pics when I cut the next one. I was lucky enough to find a used HP plotter very cheap that prints up to 110" long, and 36" wide. Plot out the rib, then take 3M super 77 adhesive and spray just a dusting on the back of the plotted paper rib, then stick it to the wood, then cut on the lines. The whole process from plotting to a cut rib is about 20 minutes, but keep in mind that I cut the ribs in pairs so it goes a little faster than you would think.

If anyone ever has any giant scale projects in CAD that need plotting let me know, in most cases I can do as long as shipping is covered, if it takes a bunch of paper I might have to have some help with the cost of the paper.

Thanks, DAG
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Old Oct 17, 2008, 05:18 PM
Vintage Flyer
Indiana
Joined Jan 2005
1,674 Posts
Quote:
Originally Posted by dag214
gtfreeflyer,

I will take some pics when I cut the next one. I was lucky enough to find a used HP plotter very cheap that prints up to 110" long, and 36" wide. Plot out the rib, then take 3M super 77 adhesive and spray just a dusting on the back of the plotted paper rib, then stick it to the wood, then cut on the lines. The whole process from plotting to a cut rib is about 20 minutes, but keep in mind that I cut the ribs in pairs so it goes a little faster than you would think.

If anyone ever has any giant scale projects in CAD that need plotting let me know, in most cases I can do as long as shipping is covered, if it takes a bunch of paper I might have to have some help with the cost of the paper.

Thanks, DAG
Hi Dag, I have a set of plans for a 78 inch JN-4 Curtiss Jenny on a CD.
Can you print something like that out?
I am also interested in blowing up a second set of plans to 150% or 117 inches.


Ed
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Old Oct 17, 2008, 05:28 PM
Put a bigger motor on it!
gtfreeflyer's Avatar
Costa Mesa, CA
Joined Feb 2007
1,443 Posts
Very cool. Thanks for the explanation. What is the row of holes for? Does it serve a function other than lightening? Holes like that are pretty bad for stress as you can get a "gang chain crack" that can easily run across all the holes very quickly. I've done that on one of my designs here at work, and it got torn apart by the stress analysists. I think the rule of thumb they stuck to was two or three diameters between each hole. Lightening holes actually don't lighten as much as they weaken. When I'm trying to reduce weight of a part, it's much better to decrease the thickness rather than cut a hole in the part. Of course, this would be a big pain in the butt in your situation unless you have a planar next to that jigsaw. Sharp corners are another concern as cracks will propogate from here. Try to put corner fillets, even 1/16" radius will do, wherever you can.
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Old Oct 17, 2008, 06:01 PM
Registered User
Texas
Joined Nov 2005
60 Posts
B-36 Fuse

DAG, you are doing the same thing I have already been through. The mold is done. Sure would save a bunch of time.
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Old Oct 17, 2008, 06:29 PM
It only takes one good idea
dag214's Avatar
Fishers, Indiana
Joined Oct 2004
6,017 Posts
Quote:
Originally Posted by Ercoupe Ed
Hi Dag, I have a set of plans for a 78 inch JN-4 Curtiss Jenny on a CD.
Can you print something like that out?
I am also interested in blowing up a second set of plans to 150% or 117 inches.


Ed
Ed,
How big is the drawing on the CD, can you e-mail me the plans, if not I bet if you copied the CD and sent it to me I could figure it out.

Thanks, DAG
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Old Oct 17, 2008, 06:37 PM
It only takes one good idea
dag214's Avatar
Fishers, Indiana
Joined Oct 2004
6,017 Posts
Quote:
Originally Posted by gtfreeflyer
Very cool. Thanks for the explanation. What is the row of holes for? Does it serve a function other than lightening? Holes like that are pretty bad for stress as you can get a "gang chain crack" that can easily run across all the holes very quickly. I've done that on one of my designs here at work, and it got torn apart by the stress analysists. I think the rule of thumb they stuck to was two or three diameters between each hole. Lightening holes actually don't lighten as much as they weaken. When I'm trying to reduce weight of a part, it's much better to decrease the thickness rather than cut a hole in the part. Of course, this would be a big pain in the butt in your situation unless you have a planar next to that jigsaw. Sharp corners are another concern as cracks will propogate from here. Try to put corner fillets, even 1/16" radius will do, wherever you can.
The big holes on the sides are for carbon fiber tubes, the fuse breaks down into 3 parts.
The other holes are both for lightening and systems, airlines, power cords.

The right angles in the fuse bulhead is where the long fuse truss lives, this is where I get 80% of my strenght from so I am not to worried about having to many holes in each bulkhead.

Keep the in put coming though I am not ever 100% sure that anything I do does not have a better and more stronger way.

Thanks, DAG
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Old Oct 17, 2008, 06:39 PM
It only takes one good idea
dag214's Avatar
Fishers, Indiana
Joined Oct 2004
6,017 Posts
Quote:
Originally Posted by B Sickels
DAG, you are doing the same thing I have already been through. The mold is done. Sure would save a bunch of time.
This plane has a 257" span and the fuse is 182" long now. Didn't you say your molds were for a 161" fuse??

Thanks, wish you had a 182" fuse.

DAG
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Old Oct 17, 2008, 10:32 PM
Vintage Flyer
Indiana
Joined Jan 2005
1,674 Posts
Quote:
Originally Posted by dag214
Ed,
How big is the drawing on the CD, can you e-mail me the plans, if not I bet if you copied the CD and sent it to me I could figure it out.

Thanks, DAG
Dag I have the plans on an email attachment if you want to take a look at them.
emailed the files to you.
let me know if they came through.
I also have them on a CD.
I tried Kinkos here locally, but the gal running the place seemed totally stumped when I told her that I simply wanted the plans printed out.
She tried 3 times, and 3 times they did print but were on the paper the wrong way, and about 1/3 of the plans were cutout.
So I gave up, and after waiting for an hour also, I went home.
Obviously with no plans.

PS- Our VAA Chapter had a movie nigt tonight at the clubhouse at the airport. We watched a trilogy of three short movies "Flights of Courage" about the US Air Mail Service, very good, then the next one was "The Red Baron, also quite good, and the last short movie was "The Lindbergh Story".
My buddy Geoff got it through Netflicks.


THanks!
Ed
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