Beavis

My Feedback: (19)

Greetings,

I am a fairly experienced builder and pilot of smaller airplanes, but am building my first big bird - a 1/5 scale Spitfire - so you could call this a newbie question. What kind of "lead brick", or whichever type of weight, do you guys use to balance these big boys? Sometimes they (particularly scale planes and oftentimes Spits) need a couple pounds or so to be balanced, hence those little stick-on lead weights won't cut it. Any tips you could spare? Also, if one needs bigger weights on the nose, is it safe to use them on a fiberglass cowl, or do they necessarily have to be placed on the firewall?

Thank you in advance,

Bundubasher

Icthyological metal weights - most widely used and easy to cast.

Cheers

Bundu

bubbagates

My Feedback: (32)

Go to your local tire shop and see if they will give you any old lead wheel weights. YOu can melt them down into whatever shape you need

I would not put weights on a fiberglass cowl, especially with a single cylinder gas engine due to vibrations. Yu could build a tray, if there is room for it, that extends inside the cowl to put the weight where you need it.

Why not move the batteries as far front as possible as well to cut down on unusable weight or buy a heavier gas engine, better to have "usable" weight versus dead weight or a heavy spinner and prop combination

Beavis

My Feedback: (19)

Thank you both.

I already have the batteries right behind the firewall and a Zenoah G38 up front, which is probably the heaviest option for that plane. I did convert the retracts to electric (Down and Locked), which are quite a bit lighter than the pneumatic set up - this may be part of the reason for needing weight in the nose (?).

Where would one find ichthyological metal weights? Never heard of it.

Thank you again,

speedracerntrixie

My Feedback: (29)

I'm not really sure what they are called but I used them alot when I was flying Blimps for sports teams. If you go to you your local Home Depot or the like, they have Large washers that are square and about 3/16" thick. They are used to secure framework to foundations and 4 of them are about a pound.

If you decide to melt down some lead, make sure you do it outside and avoid the fumes..........Toxic.

Lnewqban

These are some solutions for RC sailboats that may be useful:

http://www.rcuniverse.com/forum/m_93...tm.htm#9412763

Beavis

My Feedback: (19)

All very helpful info.

Thank you,

cubcrasher

My Feedback: (6)

Old dead battery packs work pretty goo too.

phantomdriver

You can either move your batteries or equipment to achieve or use some adhesive whhel weights.

aussiesteve

The other name for them is fishing sinkers
You can buy them form your local tackle shop.

aussiesteve

ALL of that is very sound advice

You can also purchase Lead shot and mix it into epoxy and glue it to your firewall.

There is also a company (I can't find the name of the guy here ) who sells steel powder that can be mixed into epoxy. That method is perhaps the safest of all to use.

Beavis

My Feedback: (19)

Of course... Dummy me...

Thank you all for the great advice,

Edwin

My Feedback: (2)

I recently put a 1/4" x 7.5" dia steel plate on my firewall to balance a stearman. I needed 3 lbs to balance.
Edwin

wayne d

My Feedback: (5)

His RCU name is, ram3500-rcu
Here ia a link, http://www.rcuniverse.com/forum/m_98...tm.htm#9831343
I have used it on a Meister P-47 and its nice and heavy. Mix it up in a spare paper wing tube, let it dry and cut it on the band saw.
or just pour in behind the firewall or in the cowl, after the cowl is reinforced

wayne d

My Feedback: (5)

Here is the link in the buy and sell

http://www.rcuniverse.com/market/item.cfm?itemId=806087

nonstoprc

My Feedback: (90)

Or move the the engine forward a little bit.

hobby_man

My Feedback: (8)

egg sinkers from the bait shop

heavydriver

My Feedback: (1)

Lead/ Tungsten Bird shot for reloading shot shell mixed with epoxy. About as dense as you can get. Any good sporting goods out fit should have bird shot.

warbird addict

I used 245 grain .44 mag slugs on my SBACH 342, 18 of em to be exact, each slug weighed 1/2 oz, made a plywoog box and glued and screwed it to the engine box dropped in the 18 slugs and topped it off with 30 minute epoxy, once it dried I screwed a cover on top , I painted the box flo orange with a label that says flight data recorder LOL

jefflangton

My Feedback: (23)

Bigger engine!!! That's what I'm doing to my 1/3 scale pup. You may find that adding too much weight may in a sense make the plane underpowered. Just a thought.......

All Day Dan

My Feedback: (5)

Beavis, You're supposed to keep your ignition system isolated from the radio system by eight inches or more to keep radio frequency interference from interfering with your receiver's reception. You mention that "both" batteries are against the firewall. That should be avoided. Dan.

Beavis

My Feedback: (19)

Dan,

Thank you for your concern and attention, but the 2 batteries I was referring to are for a JR Powersafe receiver with redundant power. The Zenoah G38 has magneto ignition, hence no battery, and it is already as far up front as it can go.

I hear that Spitfires are notorious for needing nose weight. My plane seems to be no exception...

I've received a lot of helpful info on this thread. Thank you all again very much.

flyallday

Here is what I did for my Camel. Made brackets to stick out as far forward as possible and used the sticky weights (about 1lb). Didnt want to put anything in the cowl. I also cut a hole in the firewall for the filght battery to move forward.

Harry

All Day Dan

My Feedback: (5)

Beavis, engines with magnetos generate radio frequency interference just as much as those with ignition modules. Putting your receiver batteries up against the firewall puts your plane and anything near it when the engine is running in jeopody. If you don't believe me, here is an email I got from JR discussing the matter. Dan

Here is what Futaba says about the very same thing.
http://www.futaba-rc.com/faq/faq-gas.html

And one more.

crustychief

I melt used tire weights and pour it into the bottom of an upside down soda can to make a round ingot