Concrete weights ??

Posted: Sun Nov 02, 2008 10:10 am

Hi all, been toying with the idea of buying some weight moulds but instead of filling them with lead filling them with concrete.
I used to manufacture concrete products by pouring concrete in to moulds which is what gave me the idea.
You can use a water based oil to prevent the concrete sticking to the mould, I think That more concrete would be needed to make the equivelent weight of lead so I might have to fill a 8oz mould with concrete to give me 6ozs in weight.
Can anyone see any other problems I might encounter doing this??
The reason I don't want to use lead is that It's toxidity its not good at all and I would have problems sourcing the material.

I would not be using these weights anywhere near anyone else, I fish isolated rock marks where there is no-one around that could be hurt if something went wrong with the weight.

Any info appreciated cheers !!!

Occasional Joined: Dec 28, 2007 Posts: 154 Location: Barry

The only problem I can think of would be that concrete is made with chippings and the weight moulds are small , I think you would struggle to make a strong enough concrete to fit in the mould, ie if the chippings are too small the concrete would be weak.
Cheers Steve

Posted: Mon Nov 03, 2008 3:40 am

How about plaster of paris or drywall paste. The weight difference might be too big as you weresaying. Plaster of paris could be poured or you could fill both halves and close the mold. You could insert a wire to add support also. Not sure how long they would hace to sit before you could take them out. Maybe do a couple a day during the cold winter.

Posted: Mon Nov 03, 2008 8:14 am

It would certainly be interesting if there was an alternative to lead weights,keep the ideas coming lads winking

Member Joined: Oct 12, 2008 Posts: 51 Location: Sheppy

Hi all
you could try silversand,portland cement with unibond added, silversand because it would be fine enough for the mould, portland cement because the wetter it gets the stronger it gets( i think) and a bit of unibond to help tie it all together, dunno might just work,let us know how you get on
seaferret

Posted: Mon Nov 03, 2008 9:31 am

Hi, I cant imagine cement being that heavy, the weights would be quite large. Why not try pebbles off the beach, some are very dense and quite heavy, you could grind them into a more aero dynamic shape and drill a hole for the wire or line to attach it. just a thought. big grin

Posted: Mon Nov 03, 2008 10:01 am

I think it can't work very good ,because cement is lighter than lead

Posted: Mon Nov 03, 2008 10:09 am

A friend used to weld together a long bolt and several nuts fitted to it. Less toxic than lead and proberbly better for the enviroment than concerete and if you wash them off after use then they shouldn't rust to quickly.

Good luck with your quest.

Posted: Mon Nov 03, 2008 4:51 pm

Thanks for all the replies, was interested to see what other peoples thoughts were. My 2 worries were that the weight wouldn't be heavy enough, and that the concrete might crack on impact.
Gonna try and pick up a cheap adjustable grip mould off E-bay if any come up and try a few different materials.
Probably try concrete, not too worried how big the weights are (within reason) cheap material not nearly as toxic as lead gotta be worth a shot.

Posted: Mon Nov 03, 2008 7:58 pm

I remember when i were a wee lad getting excited when my dad changed his sparkplugs as it ment i would get 6 new weights for free!LOL big grin

Posted: Mon Nov 03, 2008 10:14 pm

andiroo wrote:

I remember when i were a wee lad getting excited when my dad changed his sparkplugs as it ment i would get 6 new weights for free!LOL big grin

Did try spark plugs a while ago just not heavy enough, even tried tying 3 together. The lightest weight I can get away with is 6 oz and it has to grip. Normal leads just roll round till they find a snag, even 5 oz grips do this as well.
I'm sure there's a alternative.........it's just finding it crying

lol

Occasional Joined: Nov 01, 2008 Posts: 118

My only guess would be to enclose something in a small contaner or something like an old shotgun shell what to fill it with I dont know confused

maybe a bolt with nuts on would work in the shotgun shell if you could drill a hole in the the brass bottom

Posted: Tue Nov 04, 2008 9:57 am

Water is a major componant of concrete. once concrete is dropped in water it is much lighter than lead. You would deffinatly need wires to hold bottom.This is why most areas don't allow concrete mooring for boats. It simply has no holding power.

Posted: Tue Nov 04, 2008 9:39 pm

heres one for you use your concrete mix but add iron filings ,that should get the weight up abit ,we used to use this concrete called rc35 with wire in it to make it very tuff ,but you dont need alot of it we used it for floors about 100m deep,just a thought all best gaz

Member Joined: Aug 18, 2008 Posts: 32 Location: Herne Bay

I like Gaz's idea of incorporating iron filings, but how about using a cementeous self levelling compound (you can get it in DIY shops easy enough). It has very fine granules so pours into the mould well; it has similar density to concrete too, and has a fair amount of PVA type binders. Ok, it's less dense than Lead, so a given size will be about 2/3 the mass (weight) of lead, but an 8oz mould should give you a 6oz (approx) sinker. Big downside will be the setting time - lead is quick by comparison
I'd be interested in how it works out - good luck you eco-warriors!