I have some 'liquid lead' i.e. very fine lead peletts to use for weighting a loco body.
Does anyone have any suggestions as to the best way to secure the lead in the body.
cyano-acrylate (super glue)
Do not use PVA as the acetic acid given off during curing will react with the lead causing it to expand
I hope UHU is ok because that is what I have used!
Time for the "Science Bit".
When PVA (Poly Vinyl Acetate) adhesive cures it releases small amount of Acetic Acid. It's probably a lot less than you would put on your chips (Acetic acid is what's in vinegar) so will not do you any harm, but when PVA is used to stick in lead ballast weights the acid reacts with the lead to form Lead Acetate which wants to take up much more volume(1) than the metallic lead, causing the lumps to swell. If you have just stuck the ballast to the underside of a wagon floor it shouldn't be a problem, but if you have stuffed it into a closed box - like loco side tanks or boiler - with no space to expand into the lead/lead acetate mix can split the boiler, tank or whatever it has been stuffed into, even if it is a soldered metal kit or scratch build.
So to avoid any problems either avoid using lead(2) or use a different adhesive(3) on the lead.
(1) I did do the calculations based on a full conversion of a mass of lead to lead acetate and whilst I can't recall the numbers it was quite a considerable increase in volume per unit mass of lead...
(2) Alternatives include fine steel shot (I think that is what "Liquid Gravity" is), nickle plated lead shot (apparently commercially available), and I've even got some granular tungsten...
(3) I've known people use thin superglue, or one could mix a paste of 2-part epoxy (like Araldite) and the lead shot. I suspect that an oil-based paint could also be used as a binder for lead shot.
Hope that helps
Julien
(B.Sc. (Hons) Industrial Chemistry, M.Sc. Instrumetal Chemical Analysis)
I'm so glad I asked as I would probably have tried PVA.
Thanks for the chemistry lesson as well.
It should be noted that solid lead weighs more if used in the same space as 'liquid lead'.
Obviously, it needs to be shaped to fit, and as with all lead it is best to avoid contact with the material.
I secure the solid lead I use with super-glue.
I was disappointed to find that liquid lead is magnetic. 'Solid' lead has the advantage of being non-magnetic which may be important if using auto-uncoupling magnets along with lightweight wagons.
Quote from: Neverbetter on January 26, 2021, 14:30
I was disappointed to find that liquid lead is magnetic. 'Solid' lead has the advantage of being non-magnetic which may be important if using auto-uncoupling magnets along with lightweight wagons.
technically "Liquid Gravity", which is a product name, is magnetic (as it is iron based). As far as I am aware Liquid Lead is made from lead and so should not be magnetic.
[/end pedant mode]
It crossed my mind some time ago to use the tungsten putty coarse fishermen us as weights, but getting on for 20 x the price/weight as liquid lead, then perhaps not - but being reusable and mouldable it could well have a use when say setting up locos to add weight and adjust axle loading.
If you are feeling flush, then -
https://www.amazon.co.uk/Bank-Tackle-Tungsten-Fishing-Terminal/dp/B073V6C5YF/ref=asc_df_B073V6C5YF/?tag=googshopuk-21&linkCode=df0&hvadid=340092233909&hvpos=&hvnetw=g&hvrand=17255065972793833283&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1007293&hvtargid=pla-697587280760&psc=1 (https://www.amazon.co.uk/Bank-Tackle-Tungsten-Fishing-Terminal/dp/B073V6C5YF/ref=asc_df_B073V6C5YF/?tag=googshopuk-21&linkCode=df0&hvadid=340092233909&hvpos=&hvnetw=g&hvrand=17255065972793833283&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1007293&hvtargid=pla-697587280760&psc=1)
Quote from: hughn on January 26, 2021, 14:37
technically "Liquid Gravity", which is a product name, is magnetic (as it is iron based). As far as I am aware Liquid Lead is made from lead and so should not be magnetic.
[/end pedant mode]
That's useful to know as I'd assumed the 'liquid' products were now all based on iron pellets. I tried a while ago to buy lead shot in a tackle shop and they told me in no uncertain terms it was no longer produced.
You can still buy "shot" in fishing tackle shops it's just not made from lead, your shop were obviously trying to be clever, they should have offered you the modern equivalent, and made a sale!
Quote from: Neverbetter on January 29, 2021, 11:57
Quote from: hughn on January 26, 2021, 14:37
technically "Liquid Gravity", which is a product name, is magnetic (as it is iron based). As far as I am aware Liquid Lead is made from lead and so should not be magnetic.
[/end pedant mode]
That's useful to know as I'd assumed the 'liquid' products were now all based on iron pellets. I tried a while ago to buy lead shot in a tackle shop and they told me in no uncertain terms it was no longer produced.
Ah.. I was thinking about the products you get from modelling suppliers...
As a possible source of lead shot, Soft Dive Weights may fit the bill. I think they are indeed lead, e.g.
https://www.ebay.co.uk/b/Diving-Shot-Weight/74004/bn_7023443260 (https://www.ebay.co.uk/b/Diving-Shot-Weight/74004/bn_7023443260)
If you go to a tyre fitter they will give you a bunch of old lead weights for free and you can snip bits off until you have the weight you want.
Think you'll find they use zinc or steel weights these days...
If it is just lead metal that is wanted rather than finely divided material then roofing lead flashing is a ready source.
As a source heavy pourable material then tungsten powder as used for weighting golf clubs is a possibility, tungsten being more dense than lead (1.7 x). The issue with powder or pellets is all the voids in between the material reducing the density. It has occurred to me to compare say a 1 cc cube of solid lead with a similar volume of tungsten powder with appropriate glue. Packing density assuming spheres is something like 60% to 70% at best so the difference between a shaped piece of lead and tungsten powder is possibly marginal.
Never knew that! I haven't need lead for awhile and I have a few old wheel weights.
It has got to be ask the local roofer for an offcut of lead flashing then. If they still use lead, of course.
Roofing lead is readily available. You don't even need to go to anywhere exotic to buy it:
https://www.wickes.co.uk/Calder-Code-4-Roof-Lead-Flashing---150mm-x-3m/p/241450?utm_source=google&scid=scplp241450&sc_intid=241450&ds_rl=1255384&ds_rl=1255441&ds_rl=1256318&gclid=CjwKCAiApNSABhAlEiwANuR9YL0r093JiEUbfkKDCZxf9gHv9a8l5aC49WOmG14zIRI2Y-RcQg4wMhoCKaIQAvD_BwE&gclsrc=aw.ds (https://www.wickes.co.uk/Calder-Code-4-Roof-Lead-Flashing---150mm-x-3m/p/241450?utm_source=google&scid=scplp241450&sc_intid=241450&ds_rl=1255384&ds_rl=1255441&ds_rl=1256318&gclid=CjwKCAiApNSABhAlEiwANuR9YL0r093JiEUbfkKDCZxf9gHv9a8l5aC49WOmG14zIRI2Y-RcQg4wMhoCKaIQAvD_BwE&gclsrc=aw.ds)
https://www.amazon.co.uk/Code-Lead-Flashing-Sheet-Rolls/dp/B00LAAS2RW/ref=sr_1_12?adgrpid=53051549277&dchild=1&gclid=CjwKCAiApNSABhAlEiwANuR9YCIqD_j6wZBd-VwMjv1lSDrA2BTS6C7lpIE1JEwGrpWm_8tQlYO-uRoCJikQAvD_BwE&hvadid=259086527989&hvdev=c&hvlocphy=1007346&hvnetw=g&hvqmt=e&hvrand=15793452313769225790&hvtargid=kwd-301467216953&hydadcr=28148_1752695&keywords=lead+flashing&qid=1612017033&sr=8-12&tag=googhydr-21 (http://ttps://www.amazon.co.uk/Code-Lead-Flashing-Sheet-Rolls/dp/B00LAAS2RW/ref=sr_1_12?adgrpid=53051549277&dchild=1&gclid=CjwKCAiApNSABhAlEiwANuR9YCIqD_j6wZBd-VwMjv1lSDrA2BTS6C7lpIE1JEwGrpWm_8tQlYO-uRoCJikQAvD_BwE&hvadid=259086527989&hvdev=c&hvlocphy=1007346&hvnetw=g&hvqmt=e&hvrand=15793452313769225790&hvtargid=kwd-301467216953&hydadcr=28148_1752695&keywords=lead+flashing&qid=1612017033&sr=8-12&tag=googhydr-21)
Trouble is, who would need that amount for modelling purposes!
These lead curtain weights are quite good and easy to cut to whatever size you want.
https://www.amazon.co.uk/Rufflette-Curtain-Weights-Penny-Size-Lead/dp/B0063G5P7S/ref=sr_1_37?crid=1GG0X3K4QM9C4&keywords=lead+weights&qid=1553038601&s=gateway&sprefix=lead+weight%2Caps%2C167&sr=8-37
Quote from: hughn on January 24, 2021, 20:11
Do not use PVA as the acetic acid given off during curing will react with the lead causing it to expand
That explains why it came loose then. :-\
Its a shame that hot glue is not suitable either, I have loads of that.
Quote from: Stephen Rainsbury on February 11, 2021, 00:08
<snipped>
Its a shame that hot glue is not suitable either, I have loads of that.
I'm not sure why it shouldn't be - as far as I know the hot melt glue doesn't get hot enough to melt the lead, nor the plastic kit / scratch built wagon/loco you might be sticking the lead to.
I'd have thought that if the lead shot was being poured into a cavity it could be capped off with hot melt glue. The other thought would be to run a bead of the glue along the underside of the wagon and sprinkle on & press in as much lead shot as possible before the glue cools and hardens (without burning your fingers!), or stick lead sheet down with it instead.
What the hot melt glue probably will not do is soak through the shot to weld it into a single mass, which is why people tend to use the PVA (usually thinned with water) that causes the problems. If that's the effect you are after (welded mass of shot) then thin superglue should do the job, and it might also be possible to do much the same with paint or varnish - just not a water-based one (as we may well be back to PVA again!).
Stick on lead decoration for windows can work well too, and can be cut with a Stanley knife.
https://www.ebay.co.uk/itm/self-adhesive-lead-strip-tape-for-windows-glass-crafts-4-5mm-6mm-9mm-12-Regalead/274052400219?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649