Jump to content

Acro Wot fuel tank installation


Dean B
 Share

Recommended Posts

I wondered if all you Acro Wot builders would shed some light on the installation of the fuel tank.

I have the ARTF version and rather annoyingly the supplied tank drops inside between the two bulkheads when fitting. On the Wot 4 the back of the tank extends a little through into the radio bay. Not so on the acro. I have a slightly bigger 300ml tank but putting the tape measure into the cavity shows it will have the same problem.

Any ideas would be helpful.

Link to comment
Share on other sites

Advert


Hi Dean, I wondered about that as well when I first got the kit. My solution was to cut a foam platform to position in the tank bay, foam because it could be pushed into place, and stop the tank from dropping. I also pushed foam bits around the tank to hold it steady and put some balsa across the back just to stop it from moving backwards. Had no problems with the tank to date so it seems to work OK. Hope that helps, and I am sure you will love the plane when you get to fly it. Good luck. Cheers, John.

Link to comment
Share on other sites

Yep.....bloomin' annoying isn't it Dean.....a true "schoolboy error" in my book but just about the only bad part of the model.....

I added some 20mm thick blocks of balsa to the inside of F2 & then sanded the balsa with my Dremel to suit the profile of the opening & allow the tank to fit through. When the tank is pushed home the rear edge rests on the balsa & is thus well supported...

Link to comment
Share on other sites

Yes it was a bit of a poser at first.. It would have been nice to have a longer tank that fits in there as it does in the Wot 4 but the suppliers decided to save 50p and include a small one.

I got around it by extending the base of the tank by epoxying a block of wood the the tank bottom and sanding it to the profile of the tanks walls. It now extends out of the hole by about 1/4 inch. A simple thin metal strap now holds the tank in place. A couple of blind nuts in the bulkhead to take the screws for the strap and its in and fixed nice and solid.

I had to cut the rudder off and refit it as I must have slightly overdid the super glue on the hinges whilst fitting and some ran down into the tail wheel and locked it solid preventing the rudder from moving.

Some of the fittings supplied are a bit dubious too so I dumped them and installed stronger horns and metal clevises all round.

The blind nuts that hold the wings on look suspect too. Not much thread in there. I cant believe that the supplers are providing a model with such poor fittings and fixtures. For a couple of pounds more they could include some quality items.

Link to comment
Share on other sites

Percy,

I prefer the ARTF route. i dont like building from scratch although i have done in the past . The manufacturers could provide some quality items for a few pounds more but they dont. The ARTF version is bigger than the kit build and more suited to the engine I will be fitting.

devil

Link to comment
Share on other sites

  • 3 weeks later...
Posted by cymaz on 12/09/2013 09:49:00:

I know its not the same but after a couple of club fliers lost a wot4 due to a poor stock tank, I put a Dubro tank on its side. Fitted a treat with no former cuttingcoolyes

Cymaz, you've got me scratching my head over that one - how did a fuel tank lose a model? I'm using the supplied tank in mine and it seems ok - so far!

Link to comment
Share on other sites

The bung fitting in the neck of the stock tank is not very good - easily came lose. This happend in a couple of WOT4's in our club.

A leaking tank is a sure way to stop an engine. Keep and eye on it. Maybe our fliers were unlucky or had some poor fittings - I don't know. After seeing both go in I thought it best to get a tank of known pedigree.

Edited By cymaz on 28/09/2013 09:22:42

Link to comment
Share on other sites

Hi Dean,

Just finished and flown an ARTF Acrowot and can understand your difficulty. I sacked the tank in the kit and used a SLEC tank instead. This still drops in between the two formers but a bit of foam packing sorts that out. The point I really want to make is that it is possible to get the flight battery in the same compartment either to the side of, or under whichever tank you decide to use.

I think I saw in RCM&E that 6 oz of lead were needed to blance their test model at 83 mm from the leading edge of the root of the wing. The instructions tell you to mount the servos way way back in a little cut out well behind the CoG. I put the flight battery in the front compartment. wedged it in with foam, then put two hardwood bearers immediately behind the second former and mounted the three servos on them. All being some 6 inches forward of that shown in the instructions. With an OS 55 up front, to get the CoG spot on I needed a very small amount of lead to balance the aircraft perfectly.

There is more than ample space to fit everything in a more aerodynamically sound installation and, it is easier to get to for setting up/servicing etc.

I also sacked most of the linkages prefering to use snakes and much more secure horns and clevices. I can't say that this is a problem confined just to Ripmax kits as I generally scrap most of the hardware in kits anyway. The wing nuts are easy to prize out and put decent captive nuts in their place. The engine mounting screws are dreadful and snap when tightened, and are replaced with quality items.

It seems to me that kits use items that would be barely considered up to the task. For my part, I like everything to be over engineered thus reducing the chances for a catastrophic in flight failure.

The model is a cracker by the way.

Gazza

Link to comment
Share on other sites

I made a built up Acrowot many years ago now and I think the same issue existed then - the usual fix for this is to pad the fuel tank in foam and gently force it in with friction holding it in place: the foam has the added value of reducing the vibration the tank sees and thus reduces any fuel 'foaming' which could stop an engine...

Jon

Link to comment
Share on other sites

Posted by cymaz on 28/09/2013 09:20:27:

The bung fitting in the neck of the stock tank is not very good - easily came lose. This happend in a couple of WOT4's in our club.

A leaking tank is a sure way to stop an engine. Keep and eye on it. Maybe our fliers were unlucky or had some poor fittings - I don't know. After seeing both go in I thought it best to get a tank of known pedigree.

Edited By cymaz on 28/09/2013 09:22:42

I'd assume they pressure tested the tanks ok, so I'll be looking through my tank stock to see what fits as a replacement. I've had the neck of a tank split, that was with one supplied in a YT International kit, the Wot one seemed a bit more substantial so I thought I was ok using it. Thanks for the warning.

Link to comment
Share on other sites

  • 3 weeks later...

I found the best solution is to move the tank position rearward to be better centred over the CofG. A small balsa platform on square balsa bearers at the the right height to match the opening in the former and the tank pushes a couple of inches through the bulkhead and is tied to the platform with a Velcro strap. The tank is held securely and gives much less changes in trim as it empties.

CofG was 86mm with an OS 70 for power and a 3300mAh pack in the forward compartment. No lead needed up front but I found that this was nose heavy. Although the recommended 83mm is very safe for a more neutral set up 95mm is required.

PS I replaced the supplied tank with a 12oz Dubro one.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...