4*40 Fuel Tank
10-30-2002, 02:11 PM
#1
Junior Member
Thread Starter
Join Date: Sep 2002
Location: Ocala, FL
Posts: 26
Likes: 0
Received 0 Likes
on
0 Posts
4*40 Fuel Tank
What seems to be a simple thing is giving me a problem. I am building a Sig 4*40 and am in the process of installing a Du-Bro 8 oz. tank. I am presently at the stage where the top of the fuse is still open and accessible. My problem is how best to install it so that it will be stable and can be removed at a later date if required. How should I keep it in place? Should it be padded all around? Problem is, when completed, it can only be accessed from the bottom through the former that is directly behind it. Does anyone have any good ideas?[img]i/expressions/face-icon-small-blush.gif[/img][img]i/expressions/face-icon-small-confused.gif[/img]
10-31-2002, 10:52 AM
#2
Banned
Join Date: Jan 2003
Location: gone,
Posts: 4,923
Likes: 0
Received 0 Likes
on
0 Posts
4*40 Fuel Tank
Tie a harness of dacron thread around the tank. This will allw you to have something to grab for pulling the tank to the rear for removeal. The 8 oz tanks fit snugly through the bulkhead at the wing LE without the blkhead being trimmed.
The plane will need the servos mounted as far back as possible if you are using a ball bearing engine. So, when you drop the battery and RX out (they'll be strapped in under the canopy somewhere) the tank will have plenty of room to slide out.
To keep the tank from bouncng around.. just stuff some foam rubber in on each side, and (if you can...) along the top, after the tank is in. The foam will fall ut when you remove the tank.
Lite ply is vulnerable to fuel soaking... worse than balsa, as it can delaminate the layers. Be sure you fuel-proof the interior of the fuel tank compartment, and the separated lower area with a coat of 2 hour epoxy. (goes on like paint.) When you pre-form (dampen and wrap arond a large cylinder to give it the curve, then let dry overnight... it glues on easier) the forward top deck, its a good idea to coat it with somthing t slow down fuel soaking too.
The plane will need the servos mounted as far back as possible if you are using a ball bearing engine. So, when you drop the battery and RX out (they'll be strapped in under the canopy somewhere) the tank will have plenty of room to slide out.
To keep the tank from bouncng around.. just stuff some foam rubber in on each side, and (if you can...) along the top, after the tank is in. The foam will fall ut when you remove the tank.
Lite ply is vulnerable to fuel soaking... worse than balsa, as it can delaminate the layers. Be sure you fuel-proof the interior of the fuel tank compartment, and the separated lower area with a coat of 2 hour epoxy. (goes on like paint.) When you pre-form (dampen and wrap arond a large cylinder to give it the curve, then let dry overnight... it glues on easier) the forward top deck, its a good idea to coat it with somthing t slow down fuel soaking too.
10-31-2002, 01:18 PM
#3
My Feedback: (3)
Join Date: Jul 2002
Location: Pointe Claire,
QC, CANADA
Posts: 2,015
Likes: 0
Received 0 Likes
on
0 Posts
4*40 Fuel Tank
Take a tip for the Sig SE..
Make a pull tab out of packing tape. Fold a length of tape in half, and stick about 3" onto itself at the fold. Keep teh ends free! Don't let them stick to each other! then stick the ends to the top and bottom of the tank. You should have a tab in the middle and at the rear of the tank. Secure teh tape in place with a few wraps of the same tape around the tank. Install as usual. The tab should stick out the back of the 'tank removal hole' and should be able to be pulled out by grabbing the tab!
Make a pull tab out of packing tape. Fold a length of tape in half, and stick about 3" onto itself at the fold. Keep teh ends free! Don't let them stick to each other! then stick the ends to the top and bottom of the tank. You should have a tab in the middle and at the rear of the tank. Secure teh tape in place with a few wraps of the same tape around the tank. Install as usual. The tab should stick out the back of the 'tank removal hole' and should be able to be pulled out by grabbing the tab!
10-31-2002, 01:44 PM
#4
Junior Member
Thread Starter
Join Date: Sep 2002
Location: Ocala, FL
Posts: 26
Likes: 0
Received 0 Likes
on
0 Posts
4*40 Fuel Tank
FHH & Dr. Wogz, thanks for the info. You have made my day. I will be running an old OS-40 Max H that I have had for some time. Have built plane with an adjustable mount to accept OS-40FX at a later date when the skills at flying will allow.
11-01-2002, 12:02 PM
#5
Banned
Join Date: Jan 2003
Location: gone,
Posts: 4,923
Likes: 0
Received 0 Likes
on
0 Posts
4*40 Fuel Tank
Start out usig the FX. The match is good for the 4*40. Use a 11X4 or 11X5 prop. (10X6 and you'll think it'll never slow down for landing.. because idle speed gives minimal flying power! It can fly all day at idle using a 10X6.)
Don't worry so much about any .40 being too much for the 4*40. You can easilly limit throttle travel if you think you must... but you won't need to.
The main difference you'll see flying the 4* vs the trainer is the aileron are much more sensitive. If you have dual rates.. set the aileron dual rate to 60%. Have a more experienced modeler do the test flight, and while its up a good way, practice flying it a bit. After the first flight, you shouldn't have any problems. (it is recommended by Sig as a trainer...)
Don't worry so much about any .40 being too much for the 4*40. You can easilly limit throttle travel if you think you must... but you won't need to.
The main difference you'll see flying the 4* vs the trainer is the aileron are much more sensitive. If you have dual rates.. set the aileron dual rate to 60%. Have a more experienced modeler do the test flight, and while its up a good way, practice flying it a bit. After the first flight, you shouldn't have any problems. (it is recommended by Sig as a trainer...)
