HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Nov 21, 2012, 03:27 AM
Hunting for Goat Lifters
Titus ZA's Avatar
South Africa, GP, Randburg
Joined Jul 2012
109 Posts
Great work Mike. I knew you could get the weight down. A 20% drop weight is brilliant.

Keep up the fantastic work and look forward to seeing the wings take shape.

Cheers
T
Titus ZA is offline Find More Posts by Titus ZA
Reply With Quote
Sign up now
to remove ads between posts
Old Nov 21, 2012, 03:30 AM
Caravan driver
wingnutzster's Avatar
Lanseria airport South Africa
Joined Oct 2005
419 Posts
+1 - I can't wait to see you get going on the wings

I am in the process of wrapping my plug and have already removed and re applied the packing tape twice...can't get the smooth and consistent finish that you guys get.
wingnutzster is offline Find More Posts by wingnutzster
Reply With Quote
Old Nov 21, 2012, 04:14 AM
Upwardly Mobile
mikegbogh's Avatar
Roodepoort, South Africa
Joined Aug 2007
1,037 Posts
Quote:
Originally Posted by wingnutzster View Post
+1 - I can't wait to see you get going on the wings

I am in the process of wrapping my plug and have already removed and re applied the packing tape twice...can't get the smooth and consistent finish that you guys get.
Hi Wingn,
I found the best way to put the brown packging tape on over the compound curves ,was to work diagonall and smooth it on with your finger as you go, smallish pieces at a time , and you can get good results.
cheers
pics?
mikegbogh is offline Find More Posts by mikegbogh
Reply With Quote
Old Nov 21, 2012, 04:17 AM
Caravan driver
wingnutzster's Avatar
Lanseria airport South Africa
Joined Oct 2005
419 Posts
Thanks mate I will take some pics tonight...but to be honest a little embarrassed at my first attempt

I have some Cobra floor wax, will that work or do I need to get to AMT for something more specific?
wingnutzster is offline Find More Posts by wingnutzster
Reply With Quote
Old Nov 21, 2012, 04:43 AM
Upwardly Mobile
mikegbogh's Avatar
Roodepoort, South Africa
Joined Aug 2007
1,037 Posts
Quote:
Originally Posted by wingnutzster View Post
Thanks mate I will take some pics tonight...but to be honest a little embarrassed at my first attempt

I have some Cobra floor wax, will that work or do I need to get to AMT for something more specific?
Use the Cobra Floor wax to shine your floors
Use Simonez or Ram Carnuba release wax for molding.
mikegbogh is offline Find More Posts by mikegbogh
Reply With Quote
Old Nov 21, 2012, 04:48 AM
Caravan driver
wingnutzster's Avatar
Lanseria airport South Africa
Joined Oct 2005
419 Posts
Gotcha....available in SA?
wingnutzster is offline Find More Posts by wingnutzster
Reply With Quote
Old Nov 26, 2012, 06:46 AM
Upwardly Mobile
mikegbogh's Avatar
Roodepoort, South Africa
Joined Aug 2007
1,037 Posts
Long thin wings

Hi All,
Well the weather didnt look great for sloping , so I started some work on the JS 1 wings, the first two sailplanes will have the 4.5mtr wings.
I made a set of scale drawings myself as my original 3 view was mostly for the fuselage, I then placed my templates at the panel breaks and had all the correct sizes from previous builds, after these fly I will decide if I want to change the foils on the bigger C version.
Using gravity the foam was "blocked" for each panel and 2 x kits of blocks for the wings layed out and marked , this is important as its easy to cut all left wings or too many right wings.
The bow was not cutting nicely with its new wire so although not an issue on the block , it would be a problem on the cores, I replaced the 20kg piano/trace wire with 48kg and managed some smooth test cuts.
As each panel is a different size , my base board is setup with pieces that hold the templates that are screwed down with self tapper dry wall screws, so I set up for the first and biggest panel.

As the panels are different sizes and tapers I calculate the taper as a percentage and then set the pulling strings and clips to positions on the marked swing arm as a percentage.

Once everything is in order, I switch on and let the swing arm start pulling using gravity only, the bow is quite heavy and hangs from a cord from above, so it generally stays in place and provides a downward force that keeps the wire attached to the template. The only help needed is to manually guide the wire up the leading edge on the top profiles.
There is a small notch at the trailing edge of the template that catches the wire.
Turn off the power , set up new templates , and foam and repeat many times, lucky yesterday not a single bad core out of 27 cores cut.

The foam tends to have some residual hairs from the hot wire melt and I have found ,the scouring pads you get at the hardware store, are great for cleaning this off, sand paper is no good as it damages the surface and can change the profiles.I also think that the hot wire has almost sealed the surface so want to avoid sanding and see if the wing uses less resin as the foam is less porous.

The next step is to start joining all the panels and give some thought as to how to make all the di-hedral steps out at the tips.
regards
Mike

I do apaologies if you have seen this whole foam cutting thing before but for those that havent, I think there are plans on the Charles River RC web page Google is your friend.
mikegbogh is offline Find More Posts by mikegbogh
Reply With Quote
Old Nov 26, 2012, 06:56 AM
Caravan driver
wingnutzster's Avatar
Lanseria airport South Africa
Joined Oct 2005
419 Posts
Brilliant!! I been so eager to watch work begin on the wings...your photos really illustrate the techniques beautifully -

I am going to give up on my attempts...I just can't seem to get this composites thing down and waste money at every try. Pity because I really like the results of my plug. For now watching you build is as good as it gets .
wingnutzster is offline Find More Posts by wingnutzster
Reply With Quote
Old Nov 26, 2012, 09:19 AM
Hunting for Goat Lifters
Titus ZA's Avatar
South Africa, GP, Randburg
Joined Jul 2012
109 Posts
Awesome Mike. I have been eagerly awaiting to see how the wings are made. For some reason the wings are my best part about a plane. I see it as the soul and it is what makes the plane take to the air.

I continue to sit on the edge of my seat for the next installment of your masterclass.

Cheers
T
Titus ZA is offline Find More Posts by Titus ZA
Reply With Quote
Old Nov 26, 2012, 12:50 PM
Registered User
North Yorkshire UK, on a big hill facing the prevailing wind. Coincidence?
Joined Oct 2007
915 Posts
So helpful Mike. From my perspective, don't leave anything out - the more details the better. Even the stuff that seems obvious to you!

Thanks,
Rog
Sutton Bank is offline Find More Posts by Sutton Bank
Reply With Quote
Old Nov 26, 2012, 03:04 PM
Registered User
Joined Nov 2008
187 Posts
Ditto Rog - I'm going to have to build one of those weight/pulley systems now todo my wings....


Simon
swarrans is offline Find More Posts by swarrans
Reply With Quote
Old Dec 11, 2012, 07:41 AM
Upwardly Mobile
mikegbogh's Avatar
Roodepoort, South Africa
Joined Aug 2007
1,037 Posts
No Progress to report

Hi All,
To those who were following this build thread ,no prgress to report because I have had to do some real work and also got side tracked with another project, reason being makes sense to cut all the cores with the cutter and then bag all the wings when bagging , so the production line will get moving again soon .
regards
Mike
mikegbogh is offline Find More Posts by mikegbogh
Reply With Quote
Old Dec 11, 2012, 07:56 AM
Caravan driver
wingnutzster's Avatar
Lanseria airport South Africa
Joined Oct 2005
419 Posts
uM ...PLEEEEEEEAAAAASE tell me you have found a local supplier of blue foams??? I gave up trying and had a very very kind falcon5 on rcg post me a box full from the US but it now seems the box is lost somewhere in "la la land" as he put it.

I am sommer excited now!!

I get a bunch of Isoboard every now and then, being up the road and have arranged to take all their offcut sheets and throw away's but how would you say the magical 'Dow foam' compares? I tell you this stuff is like gold here.
wingnutzster is offline Find More Posts by wingnutzster
Reply With Quote
Old Apr 08, 2013, 02:42 AM
Upwardly Mobile
mikegbogh's Avatar
Roodepoort, South Africa
Joined Aug 2007
1,037 Posts
Back at last

Hi All,
I shelved the JS1 build around December after having cut the foam cores for 2 sets of wings.
The pile of cores is cluttering my workshop so this last weekend I decided to continue with the JS1 builds.
Having labeled the cores it was easy to layout the cores and start glueing them together to make the wings, the next step was to mark up and cut out the spar groove, I decided to cut out the grove with a modeling knife and not sand it at all,
This will eliminate any dust, a fairly accurate grove was obtained and will easily take all the carbon tows, as usual I will contour and fill back to the original shape.

The aluminium tubes , for the joiner are also cut , sanded and will be bonded in against the top spar .
cheers
Mike
mikegbogh is offline Find More Posts by mikegbogh
Reply With Quote
Old Apr 09, 2013, 07:22 AM
Upwardly Mobile
mikegbogh's Avatar
Roodepoort, South Africa
Joined Aug 2007
1,037 Posts
Joiner tubes

Hi There,
A couple more pics from the weekend, so just to"recap" the top spar is layed up into the groove 14 x 48k carbon tows for the first 30 cm the 10 then 40cm futher 8 tows down in steps to the tip which has 3 x tows.
Long wings like this need more tows on the top surface than underneath as the carbon is stronger in tension than compresion unless you fly inverted

The aluminium, tubes are cut and roughed and then the foam core cut away to expose the top spar, this is sanded and dusted clean, then painted with a coat of resin, to aid adhesion. Now a mix of resin and milled fibreglass (flox) not balloons is pasted into the grove and the tube bonded in and aligned , I use a piece of an old joiner to set up the alignment.
By lifting the centre of the joiner tubes you can build in a degree or two of dihedral.

Next will be to cut out a shear web grove and complete the bottom spar.

regards
Mike
mikegbogh is offline Find More Posts by mikegbogh
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion 80 in. W/span, 1/4 scale Sopwith Triplane tenacious101010 Giant Electric Planes 1 Sep 03, 2012 05:04 PM
Discussion Dummy radial instalation in 1/4 scale round cowl greggk Fuel Warbirds 5 Jun 18, 2012 04:06 AM
Sold 1/4 scale 4 1/4" inflatable cub tires lla Aircraft - General - Miscellaneous (FS/W) 0 May 28, 2012 10:55 AM
Sold 1/4 Scale Balsa USA Cub Nice, no engine LPU in OC Ca. $250.00 stevster Aircraft - Fuel - Airplanes (FS/W) 3 Apr 13, 2012 01:17 AM
For Sale SIG 1/4 scale Cub Airframe in NJ LPU CarreraGTSCS Aircraft - Fuel - Airplanes (FS/W) 0 Mar 25, 2012 03:29 PM