1/6th A-6 Intruder Scratch Build
#51

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I have been on each one 5 times. Your on one right now. Keep on pluggin.[8D][sm=thumbs_up.gif]
David Hudson
David Hudson
#52

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Sweet post David!! I look forward to all stages 


#53

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HEY OBER- I dont need the plans, plots or documents- but can borrow the molds when you are done- oh yeah i could use a little resin and cloth too-and while your at it let me use your vacume bagging system- I'll let you know if I need anything else. Scotty
#54

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ORIGINAL: GSR
HEY OBER- I dont need the plans, plots or documents- but can borrow the molds when you are done- oh yeah i could use a little resin and cloth too-and while your at it let me use your vacume bagging system- I'll let you know if I need anything else. Scotty
HEY OBER- I dont need the plans, plots or documents- but can borrow the molds when you are done- oh yeah i could use a little resin and cloth too-and while your at it let me use your vacume bagging system- I'll let you know if I need anything else. Scotty

#55

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ORIGINAL: ianober
ORIGINAL: GSR
HEY OBER- I dont need the plans, plots or documents- but can borrow the molds when you are done- oh yeah i could use a little resin and cloth too-and while your at it let me use your vacume bagging system- I'll let you know if I need anything else. Scotty
HEY OBER- I dont need the plans, plots or documents- but can borrow the molds when you are done- oh yeah i could use a little resin and cloth too-and while your at it let me use your vacume bagging system- I'll let you know if I need anything else. Scotty

LOL.... Quit talkin, start workin

#56

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Havent thought of a paint scheme yet but have been looking. Something colorful thats for sure. The EA-6B and the A-6 variantes had a good amount of differences but mostly they are the obvious ones. The stretched nose, the bulge in the tail for the extra electronics and such but for the most part the wings and other gear was relatively the same. I never did like the looks of the EA-6B though, somehow it always looked WAY uglier than the A-6 variants.
For sure a get together will be in order when they are done, that would be awesome!
For sure a get together will be in order when they are done, that would be awesome!
#57

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Ok, on to some progress for tonight. I got the rest of the formers in so they are ready for foam and speaking of which I just got back from Home Depot on a little foam run. All I am waiting for is some wire I ordered from Tekoa for my home made hot wire bow. More on that to come though:
#58

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So are the formers spaced apart by the same distance as commercially avaliable foam sheets? John
#59

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No John, The formers are spaced based on the distance provided to me by a 3 view, so that makes it a little more interesting. But I think I have a solution so stay tuned!!

#60

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Well I have been messin around in Rhino today doing a "virtual" assembly of my mold. Its been fun and I am hoping to be able to be able to skin it and use the model to work out things like control surfaces and what not, pretty neat stuff though:
#61

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Rhino v4.0 is awesome- wish i knew how to use it more though! Would really help out with my Galaxy project!
#62

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Ok, here is basically where I am at digitally. I will keep playing around and see about adding some skin and tweaking it a bit.
#63

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looks good ian. wish i had taken the time to scan and input all of my bulkheads from the plans into cad, as it would help out alot with figuring out all those "little" details.. hell who knows, i might still do it, just gotta find a place that can scan them into a PDF format, so i can convert them to DXF..
#64

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Yeah, fortunately I didn't have to worry about scanning as I took mine straight from the 3-Views. I still don't know a lot about Rhino but I am learning by using it more and more. I am also sure there are more efficient ways of doing these things in the program but hey, I know what I know.
#65

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ORIGINAL: ianober
Yeah, fortunately I didn't have to worry about scanning as I took mine straight from the 3-Views. I still don't know a lot about Rhino but I am learning by using it more and more. I am also sure there are more efficient ways of doing these things in the program but hey, I know what I know.
Yeah, fortunately I didn't have to worry about scanning as I took mine straight from the 3-Views. I still don't know a lot about Rhino but I am learning by using it more and more. I am also sure there are more efficient ways of doing these things in the program but hey, I know what I know.
yea i hear ya on that... i know just enough about solidworks for someone who's a pro to go "wow, how dumb are you".. lol... its a process, but i've enjoyed it.
#66

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What a fantastic project. It's awe inspiring to see someone take on a project like this.
Keep up the great work Ian.
Subscribed!
Keep up the great work Ian.
Subscribed!
#67

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Thanks Brown, not too much progress tonight. I tried to hunt down some wire for my foam cutting bow but no luck. I ordered some last week but was getting impatient at the fact that it has not shown up yet. Anyways, it should be here tomorrow and I can get started on filling in the voids. In the meantime I think I will play on the computer more and see what I can get done.
#68

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Ian,
The foam you have chosen is perfect for the job ( not too soft, not too hard to carve ), but I don't think that you took enough material...
Cut the slices noticeably larger than the formers: you'll have to make provision for the convex curves.
When you'll glue the foam into the skeleton, make sure that the glue stay inside near the tubes.
If you get some glue at the sanding interface, you'll have hard spots and the carving will get much more painful.
I use a long surfboard electrical carving tool at the beginning of the carving work ( have a light hand here ) then heavy duty coarse wood work files and finish with Permagrit tools.
Always work symmetrically, alternating from right to left every 5 minutes. Have someone from outside the workshop with a good eye check your work on a regular basis ( body repair guys are usually good at this, if you know someone. Otherwise I can go to you
The last stage before glassing consists in a layer of ACE acrylic spackling filler followed by a coat of water based black paint.
This will show you all the shape flaws that need to be filled or sanded away. Alternate this filler+painting process until you are happy with the result.
Use only water based product before glassing !
No need for a perfectly smooth surface before glassing BUT the shape should be perfect. Correcting a shape defect after glassing is really, really painful.
Remember that each 100gr/m2 of glass fiber will take 0,1 mm of thickness at the glassing stage. I assume that you have taken provision for this before cutting the formers...
The fabric used for glassing shall have a very flexible rowing. Twill is what you need. Put as few layers as possible. Each overlap will cost you a lot of time to smooth down...
A total thickness of 600 gr/m2 in two layers is optimal.
Also bear in mind that the plug will get close to 100 lbs when finished. So you might need an assistant to move it around a the finish stage.
I also would like to strongly advise you not to use the aluminium sheeting for finishing the job. Engraving the final surface is time consuming enough and you don't really want to mess up with demoulding problems...
The foam you have chosen is perfect for the job ( not too soft, not too hard to carve ), but I don't think that you took enough material...
Cut the slices noticeably larger than the formers: you'll have to make provision for the convex curves.
When you'll glue the foam into the skeleton, make sure that the glue stay inside near the tubes.
If you get some glue at the sanding interface, you'll have hard spots and the carving will get much more painful.
I use a long surfboard electrical carving tool at the beginning of the carving work ( have a light hand here ) then heavy duty coarse wood work files and finish with Permagrit tools.
Always work symmetrically, alternating from right to left every 5 minutes. Have someone from outside the workshop with a good eye check your work on a regular basis ( body repair guys are usually good at this, if you know someone. Otherwise I can go to you

The last stage before glassing consists in a layer of ACE acrylic spackling filler followed by a coat of water based black paint.
This will show you all the shape flaws that need to be filled or sanded away. Alternate this filler+painting process until you are happy with the result.
Use only water based product before glassing !
No need for a perfectly smooth surface before glassing BUT the shape should be perfect. Correcting a shape defect after glassing is really, really painful.
Remember that each 100gr/m2 of glass fiber will take 0,1 mm of thickness at the glassing stage. I assume that you have taken provision for this before cutting the formers...
The fabric used for glassing shall have a very flexible rowing. Twill is what you need. Put as few layers as possible. Each overlap will cost you a lot of time to smooth down...
A total thickness of 600 gr/m2 in two layers is optimal.
Also bear in mind that the plug will get close to 100 lbs when finished. So you might need an assistant to move it around a the finish stage.
I also would like to strongly advise you not to use the aluminium sheeting for finishing the job. Engraving the final surface is time consuming enough and you don't really want to mess up with demoulding problems...
#69

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Thanks for the tips Oliver, I know I don't have enough material. I wanted to first experiment a bit before buying a whole lot of it. At $24 a sheet it was a little pricey for what I thought. Thanks for the info though.
#70

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What wing profile did you choose? Original one ?
You should be able to source this foam at half the price. Especially at the current times.
You should be able to source this foam at half the price. Especially at the current times.
#71

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For the most part. I have a cross section of the original and it is a semi-symetrical airfoil. I have the NACA profile of the base one that Grumman used before they modified it so between those 2 I have one that should be pretty close to original. Same for the stabs and the rudder.
#72

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Hey Ian,
I have a 1/4lb. spool of .020 Inconel foam cutting wire. Pretty much the best foam cutting wire available...How much do you need? I can send you some tomorrow. This stuff is awesome. No matter how hot it gets, it doesn't stretch like nichrome wire does.
Best of luck on the A-6. It looks like a great project.
Dan
I have a 1/4lb. spool of .020 Inconel foam cutting wire. Pretty much the best foam cutting wire available...How much do you need? I can send you some tomorrow. This stuff is awesome. No matter how hot it gets, it doesn't stretch like nichrome wire does.
Best of luck on the A-6. It looks like a great project.
Dan
#73

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Location: Houston, Texas.
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ORIGINAL: Details 4 Scale
Hey Ian,
I have a 1/4lb. spool of .020 Inconel foam cutting wire. Pretty much the best foam cutting wire available...How much do you need? I can send you some tomorrow. This stuff is awesome. No matter how hot it gets, it doesn't stretch like nichrome wire does.
Best of luck on the A-6. It looks like a great project.
Dan
Hey Ian,
I have a 1/4lb. spool of .020 Inconel foam cutting wire. Pretty much the best foam cutting wire available...How much do you need? I can send you some tomorrow. This stuff is awesome. No matter how hot it gets, it doesn't stretch like nichrome wire does.
Best of luck on the A-6. It looks like a great project.
Dan
I am very interested in that stuff.
How much do you sell that per foot ?
#74

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Hi Ian,
Awesome project! Looks like you have got a great start. As a suggestion, and this is one I picked up here on RCU: Before you add the foam, paint the formers white. That way when you are sanding, you will know when you get down to the hull line.....they start showing up in brown. It's amazing how easy it is to undercut when you are shaping that foam. Drywall mud works well to fill in the dents and cover the bare foam prior to glassing....It's cheap and easy to sand.
For foam cutting wire I have used safety wire for years!
Tailwinds,
John
Awesome project! Looks like you have got a great start. As a suggestion, and this is one I picked up here on RCU: Before you add the foam, paint the formers white. That way when you are sanding, you will know when you get down to the hull line.....they start showing up in brown. It's amazing how easy it is to undercut when you are shaping that foam. Drywall mud works well to fill in the dents and cover the bare foam prior to glassing....It's cheap and easy to sand.
For foam cutting wire I have used safety wire for years!
Tailwinds,
John
#75

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Ian,
i have also use safety wire, and i believe a #2 guitar string as well for foam cutting..
i have also use safety wire, and i believe a #2 guitar string as well for foam cutting..