Custom Made Tanks? Anyone?

Anyone building custom made tanks?

Or do I have o cut up a few and attempt this myself. Yes, I can do this but I don't want to.

The tank size I need has to be, 2.5" in length, (length being measured from the prop to the tail), 1" in height and 2.5" in width. Drawing supplied, when needed.

HELP!

CB

That size is not going to give much of a run time on that MVVS 49.

>That size is not going to give much of a run time on that
>MVVS 49.

Hi Bill. As the MVVS 49 and 51 only use around 90 cc of fuel (4:1 no nitro) for a pattern, the 102cc of this tank should be enough.

HH

Check with Eric Rule at RSM, he can make just about any size and shape.

OK,

What is RSM?

Charles

CB, a lot of these same questions you have asked before a few years ago when you said you were building the "Bamboo Bomber". Use the "Search Engine" that Len has provided. A wealth of information is waiting for you. Try RSM Distribution on Google.

<>

Exactly why I'm asking questions.

You have a better memory than I do.

CB

CB,

I make lots of tanks for my shed group of newbies, and although it's not my favourite passtime, I will make one for you if you don't have any success via the avenues already suggested above (or the cost is prohibitive). I'm a bit short of $$$ at the moment, so you will need to cover costs (including shipping from Australia), sorry.

Cheers,

Kim.

Kim,

Thanks, and I'll keep this in mind. As you well know, shipping to Australia is a killer!

I just sent two boxes yesterday USPO, 12" X 13" x 24", 9 lb. each. Cost for the two, 145.10. Oh and 12.00 for two boxes from a UPS store.

It was a Mystery Ship kit. The fiberglass fuselage, I cut in half.

Cb

Could you tell us a little more about what you have in mind? My impression is that you are designing a control line precision aerobatic airplane. If so, this is an unusual shape and size tank, and I wonder why.

Jim,

I do have a design I'm working on. I'm using a slightly modified Ares wing. The trailing edge is now straight increasing the LE setback a tad and I'm increasing the airfoil thickness by .1875.

Wing tips are exhagerated so I'm adding ribs in these 4.5" extended areas. I'll have a span of 55". The fuselage is only 36" with a mild nose moment creating issues.

The fuselage is far from what you would see on a contempory stunt model. this is because I'm using a design I did some years ago on a profile model. In fact, a long time ago, but no longer profile.

Sure, I've built many CL models and designed a few which I built also, but never gave any thought to the "science" of what is taking place with todays state of the art models.

A learning process for me, actually geared towards thinking about what I'm doing, instead of doing without thinking.

CB

Make up a fuel cell from bladder material. One way check valve and hemostat. Make compartment fuel proof or just bite bullet and make a 1 1/2" thick tank. Make a mock up one from soft pine and use for template. Big tanks are much easier then small tanks to make. Kenn Smith made me several 1 1/2" thick tanks for my Sig Magnums and work great. Sad that he died from cancer treatments. Anyway Eric at RMS can make you a tank. Any engine that is .49 size and only needs less than 4 oz. of fuel for pattern I would be very concerned about its power.
Dan

Dan,

Concerned in what way about power? The 49 should have power enough to fly this model.

CB

CB, I think you have missed Dan's point and the size of tank measurements you have listed I doubt will hold 4 oz.s.

>I do have a design I'm working on. I'm using a slightly
>modified Ares wing. The trailing edge is now straight
>increasing the LE setback a tad and I'm increasing the airfoil
>thickness by .1875.

If you are working on the design, one of the important design points is to ensure that the required components fit. And that any custom components are in hand. In this case, you don't really know what size tank will be required - given that there is essentially zero basis of experience with an MVVS 49.

Looking at your impressive volume of threads, I am a little concerned at your chances for success with this project. From what I have been able to glean, these features seem a cause for concern:

MVVS 49 - no one I know has ANY experience with this engine and it is certainly not proven that it is a viable motor for stunt. And you have no idea how much fuel it needs. Failing that I would make provisions for around 7 ounces.

Ares airfoil - even slightly modified, it was very thin even for a Fox (actually, *because* it was for a Fox). It would not likely be ideal for and airplane that will likely head into the 60 ounce range. Maybe Billy could make it work to a certain extent, maybe even I could make it work to a certain extent, but it's going to quite a challenge.

Unfamiliarity with common CL practices - control hardware, suppliers (RSM is of the same scale as Brodak), design practices.

Unwillingness to do research - shotgunning out thread after thread on the simplest and most well-documented details is probably OK, and people will probably respond, but it doesn't speak to the necessary attention to detail required to do a very complex project from scratch.

I do not wish to be harsh, quite the opposite. Many of us have done many such projects and we know the sort of work and knowledge is required to pull them off successfully. Almost everything you have asked about has been hashed over repeatedly in excruciating detail both here and on Stunthangar. A few hours searching would provide essentially all the answers you need.

My suggestion - maybe put aside this project and at least do some research on modern design and construction practices. SSW and Stunthangar both have quite effective search functions where you can find out the details of just about anything you could possibly need to know. Even better, try building a well-equipped kit (I would suggest a Trivial Pursuit from RSM) where you will gain experience with modern design and construction. If you can't manage the TP kit (complex but straightforward) you have no chance of scratch-building something. If you must, you can use your MVVS 49. I think it's a bad idea until you have some experience with a known-good engine, but at least you have only ONE wild variable to deal with, since the airplane is known to be good.

No offense intended, but what I see is someone trying to learn how to dog-paddle by jumping off a cruise ship in the middle of the Pacific. If you see that and want to proceed anyway, fine, you can do whatever you want and if you enjoy it, no harm to anyone. I would just feel bad if you got into this project, couldn't finish or wind up spending a year and having an airplane that doesn't work, and hadn't said anything about it.

Remember - excellence is a journey, not a destination.

Brett

>Kim,
>
>Thanks, and I'll keep this in mind. As you well know, shipping
>to Australia is a killer!
>
>I just sent two boxes yesterday USPO, 12" X 13" x
>24", 9 lb. each. Cost for the two, 145.10. Oh and 12.00
>for two boxes from a UPS store.
>
>It was a Mystery Ship kit. The fiberglass fuselage, I cut in
>half.
>
>Cb


Not that I've shipped lots of stuff to the US, but I'm pretty sure a single fuel tank in a bubble pack wouldn't be too bad (I think it's weight and size that really knock the cost up). Probably depends more on whether you want it to be registered/signed for etc.

Right, CB,

Those dimensions, for a rectanglar tank, would hold just under 3.5 fl oz of fuel. A wedge on the outboard side reduces that further. ...as would the thickness of the shell sides and ends.

Rectangular tanks - without wedge - can serve well in a stunt model, but I notice they usually can hold more than needed. Level flight at the end of the run might not bring the slanted fuel surface to the pickup tube properly, as a wedge does.

Luck!

Lou,

OK, let's work backwards.

How many onces do I need? Seven?

How long will the flight be in time?

I think the solution is a tongue muffler. I'll probably have to start another Thread to find someone that can make one with the MVVS .49's footprint.

Anyone making custom tongue mufflers?

CB

CB,

1.0 fl oz volume is 1.80+something-small cu in.

If you need, say, 7 (fluid) ounces to get the needed air time on your engine, that works out to 12.6 cu in.

Using that number, and your "cross section" of 2.5" X 1" (2.5 sq in), a rectangular tank would need to be (12.6 / 2.5) 5.04" long... call it about 5 1/8".

Again, that doesn't consider volume lost to shell thickness, plumbing, and any wedge form on the outer wall.

If you had a definite number for fluid ounces needed for the air time, you could make a start with an approach like the above. Be a bit generous, tho. It is easier to take fuel out to get airtme down to what's needed than to try to overstuff a full tank that's too small.

You're telling me I need 14 ozs to do the pattern?

I would have to place the tank above the needle valve center line.

Are they doing this?

CB

In reality I think that you would be better off with one of the 1/2A kits from Blackhawk or maybe a ARF. Sometimes you just appear to be a bit out of your league. Please understand that I am not trying to be cruel but some of your questions are borderline absurd. Some of them you could answer yourself with a little common sense applied. There is supposedly no such thing as a stupid question but there is a line. Since you have discovered Brodaks website just how many 14 oz. stunt tanks do see listed???????

You learn by doing. If you rebuke answers don't ask ! Some replies are very good others may not suit your intent. Do what you want and use out of date or cheap engines and enjoy. A Fox .35 uses close to 4 oz. of fuel for pattern. Do you think less than 4 oz. will be ok for a .49? If it is good for you. Use 1/8" wire horns and Morris controls for .49 power. 3/32" are to lite duty. If you do not like my post thats fine do your thing.
Dan

rebuke?

My questions are all good ones. Remember, I haven't built CL models in 48 years. 48 years!

Loosing sight of that? Just view me as a newbie.

I'm just looking for honest straight answers from fellow modelers.

Nothing difficult about that.

If you don't have the answer, don't reply.

You would be surprised what replies can tell you.

CB

>rebuke?
>
>My questions are all good ones. Remember, I haven't built CL
>models in 48 years. 48 years!
>
>Loosing sight of that? Just view me as a newbie.
>
>I'm just looking for honest straight answers from fellow
>modelers.
>
>Nothing difficult about that.
>
>If you don't have the answer, don't reply.
>
>You would be surprised what replies can tell you.
>
>CB
>
>
>
Maybe they appear to be good questions to you but I think that you might be alone on this conclusion. I have suggested the "search engine" a couple of times and Brett has given what I feel is the most sound advice you could possibly ask for. Hopefully you will take it. Your last sentence pretty much tells it like it is.

OK,

Back to the tank issue. Now that I've decided to go with a tongue muffler, AND eliminate the RE by rotating the cylinder, I'll have more space for a larger tank.

I plan on measuring my space, and I'll make a drawing.

Possibly something off the shelf will work. I'm not farmiliar with CL tanks so someone may be able to offer a suggestion based on my engine placement, and location.

Thanks,

CB

Brodak has large selection of fuel tanks ,measure your space and put in the largest tank that will fit . Here is their website;

http://www.brodak.com/shop.php?pageNum_ProductInfo=8&totalRows_ProductInfo=205&CategoryID=47



Also RSM has big selection of tanks also , their website ;

http://www.rsmdistribution.com/index-2.htm