Jump to content
Sign in to follow this  
MikeDaBike

What do you use for balancing your gliders ...

Recommended Posts

MikeDaBike

To make proper lead shot originally they dripped molten lead from a very tall tower into water - surface tension pulled it into spheres on the way down then the water set it into shape. Anyone know if they still do it that way now?

Pouring molten lead into a dunked nose scares me witless - I think I'd always prefer to mix fine shot with epoxy and pour it in cold really. It's not quite as dense that way though, so takes more volume for the same weight.

Hi yoyo, Where do you buy your fine shot ? Mike

Share this post


Link to post
Share on other sites
Yoyo

Hi yoyo, Where do you buy your fine shot ? Mike

Umm. I don't, that's just the method I would use if I had to do it...

I tend to buy second hand so usually the noseweight has already been done by whatever means.

Looking around I see http://calderlead.co.uk make fine shot and have a 'consumer' page although you do need to ask them for an individual quote, and on EBay there are things like http://search.ebay.co.uk/150488248066 which look like a good place to start.

I guess it's a thing people don't buy very often (1kg would do a lot of gliders...) but if some enterprising shop (hint hint T9 et al.;)) were to buy a commercial quantity and split it up that would be extremely useful...

Share this post


Link to post
Share on other sites
satinet

Like I say lots of techniques work. I did a lead pour today because it was the only way I could get enough nose weight in to fit the battery I had made for the nose ( |||- ).

You are big enough boys to make your own mind up about safety and what not. I don't like working with molten lead if at all possible.

Fine shot works well. You could even push the battery in to it with some release agent. The model before this one I just beat a bit of lead in to a shape with a lump hammer and glued it in. I have tried pushing stuff in to the nose and pushing that in to sand and pouring lead in to that. All sorts of things work!

Share this post


Link to post
Share on other sites
Mr Ed

The shot doesn't have to be too fine. Unless the nose is tiny you get the same density if you use a constant size shot. The only way to increase that is to have two sizes of shot where the smaller shot is about 25% of the size of the larger one.

Share this post


Link to post
Share on other sites
Mr Ed

Currently my dive store in land locked Oxford sells shot at £7 a kilo in bags of 1, 2 and 3 kilos. They also sell loose. This is the price of lead. I doubt T 9 could sell it cheaper and the postage would be a sod.

Share this post


Link to post
Share on other sites
oipigface

You can see the way I do it in the second part of my build log in the thread called 'Building a Schwing'. Make a mould by shoving the plane's nose into damp sharp sand. Then find out how much weight you want to put in to leave the CG the farthest back you'll ever want it . Working somewhere well-ventilated, weigh out lead, melt it (I use a Camping Gaz stove, and a cheap camping billycan thing), pour into mould. Fix into nose with epoxy. CG adjustments I make with wheel balance weights.

Share this post


Link to post
Share on other sites
oipigface

P.S. John Bennett is quite right to point out the dangers involved in working with molten lead and water. The sand mould doesn't have to be very wet, just wet enough to stop the sand flowing.

Share this post


Link to post
Share on other sites
isoaritfirst

When I mould lead I sometimes wrap tin foil around the nose. thick stuff such as off a Mr Kiplins apple pie.

Then stand that in the sand to hold it up.

After moulding give it a good few whacks with a hammer to beat it to a smoother shape.

Don't eat the apple pie until you have washed your hands..

  • Like 1
  • Haha 1

Share this post


Link to post
Share on other sites
f3fman

When I mould lead I sometimes wrap tin foil around the nose. thick stuff such as off a Mr Kiplins apple pie.

Then stand that in the sand to hold it up.

After moulding give it a good few whacks with a hammer to beat it to a smoother shape.

Don't eat the apple pie until you have washed your hands..

When are you next moulding some lead ? I'll bring the custard :)

Share this post


Link to post
Share on other sites
rumbey

I get mine here. http://www.ebay.co.uk/itm/150441459612?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

Cast lead Ingots. Reasonable price too

Share this post


Link to post
Share on other sites
MikeDaBike

I get mine here. http://www.ebay.co.u...984.m1438.l2649

Cast lead Ingots. Reasonable price too

I ended up buying the following :

http://www.ebay.co.uk/itm/1Kg-LEAD-SHOT-SCUBA-DIVING-WEIGHT-BALLAST-/150488248066?pt=UK_SportingGoods_Scuba_SnorkellingEquipment_SM&hash=item2309cc6f02#ht_1605wt_1139

Arrived quickly and for me is a convenient size (about 1mm) to pour into the nose & glue. Mike

Share this post


Link to post
Share on other sites
JG

Hello Everyone - I've just brought a Multiplex Balancer seems to work fine but not yet flown any models after balancing them on it :rollyeyes:

Share this post


Link to post
Share on other sites
bogbrush

I use lead flashing to make nose slugs and adjustment weights:

 

- if you see a house having a roofing job check the skip !

i tend to make a slug to fit inside the nose then file it back to adjust C/G

 

1 get plasticiene and roll into sausage shape then wrap in cling film (not too tight), push this as far foward as itll go in the nose, the leave it somewhere col to go harder, then pull out again with the trailing cling film . Plug should be shaped like inside of nose-cone (nb, some folks use clay).

 

2 pour some fine sand into a plant pot then put the plasticiene plug in, suspended verticaly (just hold on to it), fill around it with more sand and add water to wet the sand and make it all stick together. gently pull out the slug. this leave sand teh same shape as the slug (coarse sand works, but less well)

 

3 Whilst still wet pour your molten lead into the hole and before it has set insert a screw thred into centre holding it with pliers and let it cool.

 

4 when set pull out the shaped lead slug and clean up with a file. the screw allows you to repeatedly trial fit and adjust with a file until the fit is good, without it ever getting stuck.

Share this post


Link to post
Share on other sites
oipigface

I've not tried the plasticine trick, but it seems unnecessarily complicated. The outside profile of the nose is more or less the ams shape as the inside. I just shove the nose into the wet sand, then carry on as in 'clumpflier''s post.

 

I make my cast lead nose weight the right weight to bring the CG to the farthest rearwards I think it is ever going to go. Then I use 5g wheel balancing weights for fine-tuning. These come with adhesive backing, so they can be stuck to the battery or anywhere that's convenient. I also use them to find out how much cast lead weight is needed. (Take a look at my thread on Building a Schwing.)

Share this post


Link to post
Share on other sites
isoaritfirst

Try, rather than filing your lead just tapping it into shape with a hammer.

 

Saves getting covered in lead filings, and also will improve the external finish after sand moulding.

Share this post


Link to post
Share on other sites
Rob Thomson

I used this rather simple method the other day.. 1. Got the model balanced using small bits of lead flashing pushed up into the noses. 2. Took out the bits and snipped them all to about 1cm x 1cm in size. 3. Squeezed a load of silicon into the nose. 4. Dropped all the lead bits into the silicon and smoothness off. Job done! Guess the same can be done with epoxy... But silicon can be removed a bit more easily!

Share this post


Link to post
Share on other sites
Yoyo

I used this rather simple method the other day.. 1. Got the model balanced using small bits of lead flashing pushed up into the noses. 2. Took out the bits and snipped them all to about 1cm x 1cm in size. 3. Squeezed a load of silicon into the nose. 4. Dropped all the lead bits into the silicon and smoothness off. Job done! Guess the same can be done with epoxy... But silicon can be removed a bit more easily!

 

You must fly bigger fatter planes than I do...  ;)

 

There's barely enough room in for instance a Sunbird to get the lead in there.

Share this post


Link to post
Share on other sites
Rob Thomson

Depends on the model. You can always cut the lead smaller :) I sometimes use a round fishing sinker in the nose... Then the lead flashing butted up against that in the smaller gliders.

Share this post


Link to post
Share on other sites
Yoyo

Depends on the model. You can always cut the lead smaller :) I sometimes use a round fishing sinker in the nose... Then the lead flashing butted up against that in the smaller gliders.

 

I use 1-2mm lead shot but silicon does sound like an interesting alternative to epoxy. No reason not to pre-mix it either - as you press on it (messy job) the lead shot should push densely to the front as the silicon oozes back.

Share this post


Link to post
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.   Restore formatting

  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.

Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.