They are easy to use Lead pellets, just put superglue inside the bottom of the base, then hold the base over a tray to catch the excess Lead balls as these little beggars will roll all over the place and get absolutely everywhere. If you've got that hard flooring, then these balls will be worse than those things the Ninjas use! They roll really well because they are heavy and very uniform. Personally I keep them in an old plastic "take away" container.  They are also absolute beggars to pick up, because of their size you cannot get your fingers round them. Try using a good sticky tape wrapped around your hand, to dab them up, then rub over it with the other hand over your container. Wash your hands afterwards as the item contains Lead, do not place in the mouth or swallow as it may be harmful if eaten or chewed.  Wash your hands after handling and keep away from foodstuffs.

Anyway, once you've got the glue in place, let it run around a bit (or use a toothpick to get it into the corners) and then pour on the Basing beads. Use a flat edge, such as a steel ruler or knife blade, to remove the excess, moving it across the bottom of the base.  Leave to dry (do not turnover until fully dry!), and then give them a tap to check they are all attached. You can put an extra dab of superglue on top if you wish, personal choice really. Then use plastic glue to attach the model to the top side. Superglue dries pretty quick, so you can use these basing weight balls if the models already attached, but it's easier to do it prior.

Once the Lead beads are fixed in place, they shouldn't really come in contact with the hands, due to the way miniatures are handled, by the sides of the base, or people picking up the miniature itself.  If correctly fitted, then the surfaces that bases are placed on won't be discoloured, as the actual beads will be inset.  But it is possible that storage foam might come into contact with the attached Lead pellets if there's a hell of a lot of prolonged shaking about, or they are depressed right into it. I can't see that being a big issue, but thought I'd mention it.  A spray of undercoat over the base balls would sort that, or if the models been already painted, then a dab of black paint would seal them in. If you've put a layer of superglue over these little Lead spheres, as mentioned prior, then that would also sort it. Just thought I'd mention that for completeness, so you are covered. Remember if you do use superglue, then you'll get what's known as "bloom." This is the white vapours that will show clearly on the black plastic, due to superglues drying process. It can be rubbed off, or painted over, but be aware that it can occur.

You may well fill your bases with Milliput (modellers Epoxy putty), Plaster of Paris or my preferred Base weight beads (because I sell them!). Seriously though, I've used Milliput and it doesn't bond well with the plastic and neither does Plaster of Paris. They do work, but they are messy, it takes ages to do and neither have the weight that Lead shot does. I definitely know that Milliput can later pop out of the base (as plastic gradually degrades and shrinks slightly over time), to which you then need to glue the Milliput back in again. I'm telling you this happens, as it happened to me, and it's a ballache! Some people use 1 pence or 2 pence pieces to weight bases, but again these coins do not have as much weight as the Base beads and, as with some base weight plugs that are sold by people, they can only be used for specific sizes of plastic bases. If you use 1p and 2p coins and want to have a magnetic ball in Bloodbowl then you may have to drill through the coin, which isn't easy. Plus the Base weight beads weigh more than these coins, which is the whole point and purpose of weighting your bases. I truly feel that the way to go, is to put a magnet in the base, a second one for the ball if needed (ensure you get the polarity the same way around) and to fill with Base weighting beads.

The Lead Base weighting beads will roll and form into any space. This flow of base balls means that they can be used for a multitude of different base sizes. 1p and 2p coins do have the advantage that the newer minted ones (since September 1992) are not actually copper. This is because copper is now more valuable in weight than the coins value that it represents. Instead the newer coins are actually a mild steel core and electroplated in copper so are actually attracted to a magnet. An advantage being that you can then use magnetic sheeting on the shelves of a miniatures storage box to attach these to, or the movement trays, for transport. If you do this then please be sure to fix the coins in such a way that minimises the distance between the coin and the magnetic material. Due to the thickness of the coin and the depth of some bases you can get an air gap, which will affect grip dramatically. If you place the coin on the table and place a small ball of epoxy putty on top, then force the base down onto it, the coin will be flush to the bottom of the base. As I said earlier though your epoxy putty may lose it's grip over time, so when it's set you may want to dab on some superglue so that it runs round the hidden side of the coin to ensure it remains solid. Always wise to do this kind of work prior to having glued your miniature on the base, as the bases can just be turned over and will lay nice and flat.

You can buy flexible adhesive backed magnetic material in tape, off a reel, or in sheets to cut yourself using scissors. You can also buy this magnetic material in precut pads for the bottom of bases for when the sheet is put on movement trays. The disadvantage being that the magnetic material works out pretty expensive when you add it all up, for the overall coverage that you are going to need for a Warhammer army. If you go that way make sure you get it in a thickness to give a good strong hold (be aware that magnetic sticky tape on a reel can be super thin and offers little grip). I've seen people put magnetic sheeting under the bases, on the top of the movement tray, then also underneath the movement tray, and also on their storage trays. Easy carriage, time saving to game, but this works out hideously expensive. The individual miniatures look nice from underneath though, but the movement trays depth is virtually taken up by the magnetic material. So miniatures tend to ride high in the standard trays. Also, When you use this magnetic sheet, you need to get the polarity right. I don't think a lot of people are aware of this issue. If you have regimental type bases, and cut the magnetic sheet in squares, it will not hold anywhere near as well if turned 90 degrees. This means if you have a 5 x 5 square movement tray, you need to align all the pads correctly before sticking them on. If you wish to use a 5 x 6 movement tray, thinking that you can have a different frontage (6 at the front with 5 ranks, or 5 at the front with 6 ranks), then it won't work. Unless you want them all facing the wrong way in game or not attaching as well to the tray in game. I know this for a fact, as I've fiddled here with it myself. An example being lightweight 1998 era Skaven slaves on 20mm x 20mm square bases (pre Age of Sigmar, AOS). I can hold the tray upside down if the minis are on correctly, but turn the bases 90 degrees then you've got no chance. The Skaven slaves are very light metal miniatures, not weighing much at all, if you have heavier miniatures (not so much an issue with plastics) then you will have problems. Just ensure that you use thick enough magnetic sheet because if it's too thin, the sheet will not have enough magnetic strength to hold the model in place, be sure to check your largest model first. 

I genuinely think that you are better off putting the much more powerful magnet in the base and instead using a steel tool box which they will then attach to (utterly excellent for 1st edition Man O War miniatures, which even have a hollow for the magnets). You can use magnets with a thin carbon steel shim or (also called steel foil, steel sheet or steel paper) on your movement trays, but it rusts, so you'll need to coat it with a non waterbased undercoat. If you are using carbon steel shim, degrease it and clean it up prior to painting, or any paint you put on will just not get a good grip and will lift off. This is because of the oil on the rollers, that is needed to manufacture the carbon steel shim. For cleaning it I'd advise Acetone (which is available in some nail varnish removers) or perhaps Isopropyl / Isopropanol alchohol (it's flammable, take full safety precautions). They'll evaporate leaving the surface clean, rather than a petroleum based such as White Spirit, although you'll get away with useing the latter. Get the right shim, don't buy stainless steel, it's more expensive and the magnets will not grip to it well, if at all. Please be aware that the thinner the shim, the more expensive it can get so to go a little thicker means you save money. I'd advise to buy it on a roll, rather than sheets of it, to save on wastage. The thinner shim steel can be cut with scissors, confirm with the seller first, tell them what you want, and they may even send you a few off cuts to test your magnets grip on. Magnets will also be attracted to the magnetic sheet but nowhere near as well. Even using large ones, 5mm x 2mm, the grip will be weak, so not very practical. If you choose to use magnets with the steel shim on your movement trays, this is a win win situation, but may well fall out of fashion over time because of the more skirmish orientated Age Of Sigmar (AOS) rules. They really make a difference with plastic miniatures. I truly feel that to have magnets in the bases and carbon steel shim is the way to go, but it may come down to personal preference. You may instead wish to use magnetic sheet to attach to carbon steel shim lined boxes. I like KS storage, but setting up my Skaven army takes an age.

In a separate listing I also sell small self adhesive pads to cover up the base weight beads. These are mainly sold with Bloodbowl in mind, to offer grip on the board, but might prove useful to you as they do look nice. The Velour pads are a synthetic material and finish off the base of any miniature nicely. They cover and effectively seal in these Lead balls and can be seen here: