Fuel tanks 3 oz

Ken Cook wrote:GRW tanks RSM Distribution. They're going to cost more than Brodak tanks due to the fact that they're built properly using quality materials.

Thanks Ken, was hoping someone was cheaper than Brodak. Also do ya know who might sell a 3oz plastic clunk tank?

GRW tanks are much more expensive than Brodak but they work so the cost shouldn't be a concern. For the record, I've almost never had a Brodak tank work out of the package. it's leaking prior to putting fuel in it, the pipes fall out due to vibration. The seam leaks due to a non seamed joint. GRW is a quality built tank. Mecoa has purchased the Hayes plastic tanks. I don't know what sizes they offer. Certainly worth a peek.

Ken Cook wrote:              GRW tanks are much more expensive than Brodak but they work so the cost shouldn't be a concern. For the record, I've almost never had a Brodak tank work out of the package. it's leaking prior to putting fuel in it, the pipes fall out due to vibration. The seam leaks due to a non seamed joint. GRW is a quality built tank. Mecoa has purchased the Hayes plastic tanks. I don't know what sizes they offer. Certainly worth a peek.

Ken i just went to RSM Distribution and their tanks are cheaper than Brodak.  But i don't see where it says there GRW tanks.
http://www.rsmdistribution.com/index.php

On the profile uniflow tank, after refueling do you cap the fill/vent  or the overflow?

Hobby King USA has the 3 oz. clunk tanks available, $2.56 plus shipping.

https://hobbyking.com/en_us/fuel-tank-90cc.html



I don't know how long they will have them in stock. Also, I don't know how reliable they are now under Covid.

GallopingGhostler wrote:Hobby King USA has the 3 oz. clunk tanks available, $2.56 plus shipping.

https://hobbyking.com/en_us/fuel-tank-90cc.html



I don't know how long they will have them in stock. Also, I don't know how reliable they are now under Covid.

Thank you for the post info.

I have always made my own tanks.
I get the  "kit" from Brodak and solder it up.
You can purchase the 3 oz. tank and make it yourself.

It's not very hard to do.
I've been making my own tanks for years from simple fuel tanks to uniflow, to chicken hopper tanks.
Give it a try. You just need a 80 watt soldering iron.
40/60 acid core wire solder (wire size/guage 0.080")
You can get both of the above at your local Walmart or Menards.




And the 3 oz. Wide Wedge Uniflow Fuel Tank Kit 3 by Brodak (SKU# BH-783) for $14.99


Here are some fuel tanks I made for a friend for a trade.
I got "3" Tee Dee 020 engines (engines of the month - November) for making the tanks for him.
1/2oz. tanks and 1/4oz. tanks

Sosam,
I'd love to see one of those tanks on a plane and hooked up. I don't understand how the strap is used, or the orientation of your feeds with respect to the wedge.
Is the wedge a trough at the bottom of the tank?
Can we get measurements for a sense of scale?

Thanks in advance,

sosam117 wrote:I have always made my own tanks.
I get the  "kit" from Brodak and solder it up.
You can purchase the 3 oz. tank and make it yourself.

It's not very hard to do.
I've been making my own tanks for years from simple fuel tanks to uniflow, to chicken hopper tanks.
Give it a try. You just need a 80 watt soldering iron.
40/60 acid core wire solder (wire size/guage 0.080")
You can get both of the above at your local Walmart or Menards.




And the 3 oz. Wide Wedge Uniflow Fuel Tank Kit 3 by Brodak (SKU# BH-783) for $14.99


Here are some fuel tanks I made for a friend for a trade.
I got "3" Tee Dee 020 engines (engines of the month - November) for making the tanks for him.
1/2oz. tanks and 1/4oz. tanks

Thanks for that, i have made some tanks in distant past. I ordered a tank from RSM distribution a 3oz uniflow for $12.00. trying this tank in a super satan I'm building now. The 3oz clunk i was looking for will be put on a Sig 35 Skyray.
Thanks everyone for your help.
jim

Typically, the uniflow pipe is the pipe closest to the pickup. You fill through the uniflow and cap the overflow leaving the uni pipe open to the wind. Always fill through the uniflow or else you will not fill the tank completely. However, this might work, it might not work. If the tank is subjected to vibrations, uniflow is not going to work properly. I put a spritz of Armor All in the fuel and try again as this can stop the dreaded fuel foaming. When doing this, I like to launch quite rich because on release, the engine may instantly go lean. To circumvent this, I neck down the uni pipe. To do this, I have put the yellow caps that come with a Brodak tank on the pipe itself with a smaller hole in the end of it. I have also used a smaller piece of 3/32" tubing inside the 1/8" to neck it down.

                If using the tank on a profile, it's also important to get your uniflow pipe out into clean air. Due to the engine cylinder laying down and in front of the tank blocking the flow of air into the pipe, you can do a few things. You can route a piece of pipe through the fuse and out onto the inboard side of the fuse pointing into the wind. You can also extend the uniflow pipe with a 2 " piece of tubing and just let it rest directly on top of the cylinder head. Your just trying to get your uniflow pipe out of turbulent air.

            If the uniflow proves to be problematic, you could cap the uniflow and leave the overflow open and the tank is now running on standard vent. Keep in mind the engine will run richer in the first few minutes of the flight leaning as the tank depletes.
Another thing that I've been plying with has been wrapping the tank in bubble wrap prior to mounting. This has been very successful. While it's not pretty, it's effective. I wrap 3-4 wraps around the tank and rubber band the mess onto the plane. Most profiles suffer from vibration and this was a quick field fix for a few planes that were not cooperating.

944_Jim wrote:Sosam,
I'd love to see one of those tanks on a plane and hooked up. I don't understand how the strap is used, or the orientation of your feeds with respect to the wedge.
Is the wedge a trough at the bottom of the tank?
Can we get measurements for a sense of scale?

Thanks in advance,

O.k.

Yes, the wedge is a trough at the bottom of the tank, so you get every drop of fuel in the tank.
I run fuel allotment events and the tank is measured by the contest director for fuel size.
If the tank is bigger than the fuel allotment. Your tank is only filled with that allotted fuel for that event.
With the measured fuel tank you can top off the tank before releasing the plane
This is an event for SAM (Society of Antique Modelers) called "Texaco". Longest flight wins (engine plus thermals)
There are three different Texaco events. One called 1/2A Texaco. Which uses the Cox 049 with the 5cc tank. The next is "A" Texaco which limits the engine size to .051 to .20cc and fuel to 14cc for glow / 8cc for diesel. Then the "Big" Texaco .21 to.90cc with fuel allotted up to 28cc. Favorite engines for "Big" Texaco are the Open Rocker 4 stroke engines.

Here are my uniflow tanks mounted to my Enya 06 glow and Enya 06 diesel.

This photo of my Enya 06 glow shows the uniflow tube up over the engine to get "clean" air (from the prop) to push air into the tank. The bent tubing goes to the bottom of the tank -- above the fuel pickup (the wedge -- "Vee"). The fuel is sucked up from the bottom of the wedge to get every drop of fuel. I cap off the overflow vent so the bent pipe will pressurize the tank from the prop wash.
This is why I have a left side or right side tank depending on which side the fuel nipple is on.



This photo shows this tank's uniflow where both the fuel pickup and intake (uniflow vent) go to the bottom of the wedge.
I have not capped the vent tube yet as this was a photo before fueling.
I wanted to see the difference it would make to have the bent tube pressurize the tank verses a straight tube.


The last photo is of my Enya 06 diesel. With the tank from the photo above. The bent tube as the fuel pickup and the straight tube as my uniflow vent. and as usual, I'll cap off the vent when I fill the tank.
Then, I tried the bent tube uniflow tank facing the prop wash.
With the diesel, it has more than enough suction compared to the glow, it didn't matter to have the bent tube face the prop wash or have the straight tube uniflow tank.


As for the brass strap. It just makes it easier to mount the tanks to the firewall of the plane or the side of the plane.

@Sosam117.
I am new to this forum so Hi and I hope I am not too late to reply as your input is a few years old now.
I have a standard Cox 049 just arrived but without fuel tank.
It has what looks like a plastic back plate fitted to it which holds the needle valve and four mounting holes.
I have ordered a tank but it will take many weeks to arrive from Canada to Australia.
So I thought I would make a tank.
I have made tanks before from tin plate and brass tube for diesels but I read here on the forum that brass and nitro glo fuel do not go together well.
So I can knock one up from an old baked bean can but need to source the copper tube somehow.
My question is that of fuel tank feed tube height to the feed at the bottom and back of the engine.
No matter where I mount the tank the feed tube from motor will obviously come from the bottom and have a loop in it until it gets to the feed pipe at the bottom of the tank.
Will the engine still suck up the fuel?
Make the loop as short as possible?
Height of bottom of tank feed pipe to fuel intake on engine?
BTW I really like your machined ally engine mount with machined in downthrust.
I am clearly writing to a serious modeller!
OHH....I get the bit about ordering the tank kit but I will have the same problem with the long postage wait.

Woody wrote:@Sosam117.
I am new to this forum so Hi and I hope I am not too late to reply as your input is a few years old now.
I have a standard Cox 049 just arrived but without fuel tank.
It has what looks like a plastic back plate fitted to it which holds the needle valve and four mounting holes.
I have ordered a tank but it will take many weeks to arrive from Canada to Australia.
So I thought I would make a tank.
I have made tanks before from tin plate and brass tube for diesels but I read here on the forum that brass and nitro glo fuel do not go together well.
So I can knock one up from an old baked bean can but need to source the copper tube somehow.
My question is that of fuel tank feed tube height to the feed at the bottom and back of the engine.
No matter where I mount the tank the feed tube from motor will obviously come from the bottom and have a loop in it until it gets to the feed pipe at the bottom of the tank.
Will the engine still suck up the fuel?
Make the loop as short as possible?
Height of bottom of tank feed pipe to fuel intake on engine?
BTW I really like your machined ally engine mount with machined in downthrust.
I am clearly writing to a serious modeller!
OHH....I get the bit about ordering the tank kit but I will have the same problem with the long postage wait.

Woody. It would be best to keep the fuel line as short as possible, but dipping down low under the engine to enter the spray bar from the bottom shouldn't pose a problem if you make sure that the tank pick-up is level with the centre-line of the venturi. To save the fuel syphoning don't have the tank any higher. A couple of MMs lower won't hurt and may be a safer option. It should still draw fuel ok.

Woody is there a Hobby Lobby near you ? If so they carry pretty much everything you need to make your own tank including metal tubes instead of copper . https://www.hobbylobby.com/Crafts-Hobbies/Hobbies-Collecting/Tools-Blades/Assorted-Brass-Soft-Bendable-Metal-Tubes/p/59087

Eric, it appears that Australia, where Woody alluded to be from, does not have a Hobby Lobby (American chain store).

Woody wrote:I have ordered a tank but it will take many weeks to arrive from Canada to Australia. So I thought I would make a tank.

Are brass tanks really nasty? Some sea fittings on ships are made of brass, because they do not corrode like steel does. Many of the CL kits of the past came with brass tanks.

My 30-in wingspan OK Model Pilot Cessna 177 Cardinal kit:


Brass tank as installed:


Old surgical rubber tubing used back then used to go bad in short order, needing replacement, just saying.

Check your local.auto repair parts house for a mechanical oil pressure line kit. You may find it is 1/8" soft copper line. Even brass will work for a while.

At the end of the day, you use what you can find...I used locally-sourced twisted strand picture hanging wire for lead-outs until I found more appropriate wire at the hunting store. My first tanks were made with a piece of oil pressure line as I indicated above. And I sourced some of my fuel line from the IV tubes used during my back surgery and "the very special internal camera glamour shots" most of us endure when over 50 yo! The nurses look at me funny until I mention what I keep it for!

Hi Guys and I really appreciate you inputs and interest. I do have a good model shop about 40 Kms away and yesterday I bought some nice very thin steel plate coated with tin ( KS metals).
Also to my surprise they had the 1/8th OD thin walled copper tubing.
Game, set and match!
I can now make several fuel tanks.
I can post pics of my work if you are interested.
Just need to read up about " image posting" as every forum is different.
Thank you so much for your friendliness.
I am in the right place.
For the uncertain, yes I am from Australia whereas we always mount engines upright so that they come out as inverted!!!!
When you fly inverted we see that as normal right way up!!!!
Woody.

Show and tell please!
But I have to ask...how does fuel stay in upside down tanks?

Here Pete let me help ya > https://www.coxengineforum.com/t15569-how-to-embed-a-youtube-video-in-a-post?highlight=how+to+post+images and >> https://www.coxengineforum.com/t15567-how-to-post-an-image-in-a-topic?highlight=how+to+post+images

Woody wrote:Hi Guys and I really appreciate you inputs and interest. I do have a good model shop about 40 Kms away and yesterday I bought some nice very thin steel plate coated with tin ( KS metals).
Also to my surprise they had the 1/8th OD thin walled copper tubing.
Game, set and match!
I can now make several fuel tanks.
I can post pics of my work if you are interested.
Just need to read up about " image posting" as every forum is different.
Thank you so much for your friendliness.
I am in the right place.
For the uncertain, yes I am from Australia whereas we always mount engines upright so that they come out as inverted!!!!
When you fly inverted we see that as normal right way up!!!!
Woody.

Sorry Woody for replying so late.
Been working around the house since it spring time here.
Getting the swimming pool ready, yard work, getting the snow blower put away and getting the lawn mower out and working.

Anyway, You are on the right track.
I get my tank building supplies from K&S (hobby shop).
The other place is Brodak with his tank kits.
https://brodak.com/catalogsearch/result/index/?p=5&q=tank+kits

I also see you got many good replies from your question as well.
Best of luck!