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[Black Shoe]

I'm building a small RC trawler and have the majority of the components and ballast installed. It seems I need just an ounce or so of ballast (lead shot) to finalize the trim. I don't have any clay, but thought if I put some shot in the appropriate places and melt candle wax over it that it 1. wouldn't be as permanent as epoxy, 2. would be removable if I went to larger batts, 3. easy to do. 
Any thoughts - pros or cons?

Thank you!

[Rottweiler]

 seems like an easier way of doing it, but removing it would be a pig of a job,if the wax was melted in situ,retaining the shape of the hull where it sits? unless perhaps you lightly grease the hull perhaps,so that the candlewax wont stick to it,making it removable in one piece? Dont know,perhaps it could be more trouble than you think!

[Black Shoe]

I don't know...... What I did was pour the shot where I needed it, then just held a candle over the area, and let a few drops of wax encapsulate it. My thought was any kind of glue - particularly epoxy was permanent and I wanted the flexability to move/remove the weight if necessary. My test proved pretty satisfactory in that I could move the ballast/wax with a tea spoon, yet it wouldn't drop out of the hull of it's own accord when I turned the hull upside down. This wouldn't be a good idea when dealing with a lot of weight I wouldn't imagine, but for slight amounts.....well, I'll let you know. Sea trials should be in a couple of days.

Thank you

[sailorboy61]

Can you get some clingfilm in the hull, the shot ontop and then wax it in place??

[Black Shoe]

Can you get some clingfilm in the hull, the shot ontop and then wax it in place??

I tried something very simular but it was too smooth inside the hull. If there were a couple of dams, or if I had had the forethought to glue in some obstructions to keep the stuff in place it may have worked better. The heat was hard on the film too. All in a day's experimenting I suppose.
So far, the shot on the bottom, and sufficient wax to hold it in place seems to work pretty well. It's not very pretty, but allowed a simple solution.....so far 

[deadbeat]

Just an idea - instead of wax would PVA glue do just as well.

[malcolmfrary]

A nice 1oz lump of Plasticine works well for me.  Figure out where its wanted, press down a bit, done.  Has the advantage that it can be reshaped into a slightly different position should it need further trimming.  If it needs something a bit denser, you can always embed shot into it.  I think I read about doing that in a Railway Modeller mag in the late '50's as a means of increasing traction in plastic bodied locos.

[Black Shoe]

Thanks to everyone. If it turns out the wax won't work, I'll have a couple of other ideas to fall back on.

[Black Shoe]

Although the project isn't complete, I thought I'd do an update. The candle wax has worked great. I had to shift a little ballast when I added another aux battery (lighting), and part of the wax was removed/ replaced with no problems. As I mentioned earlier, I wouldn't use this method on anything over a few ounces, but for shot it works very well.

[kiwimodeller]

Try putting your lead shot in a plastic ziplock bag and pushing it in to the part of the hull where you need it. When you are sure you have the right amount in the right place then pour some epoxy in to the bag and push the bag back down in to the hull. That way it sets to the correct shape but you can still remove it if neccessary and you can trim some off if you want to lighten it up a little. Cheers, Ian.