Maintenance & Fitting
Castors will not roll easily unless they are big enough for the load and floor conditions. Castors 75mm (3”) should only be used on light weight, seldom used equipment. Even diameters of 100mm (4”) are only useful on smooth floors. Any trolley wheeled quickly, or on uneven floors, needs wheels 125mm (5”) or larger. The heavier the load, the larger the wheel. Hard treads roll most easily on smooth floors, but may damage them, and are also hard to roll over obstructions. Most people can exert 17kg of push to get a trolley rolling, and about 12kg (26.4lb) to keep it moving. This reduces to 6kg (13.2lb) over long distances. This is the reason that ball bearings and roller bearings are more popular than plain, as they allow more load for the same push effort. Castors will not swivel properly unless they are mounted vertically. Otherwise they will track to one side.
Some recommendations Heavy trolleys need plate mountings, but the base of the trolley must be strong enough to withstand the load. Never mount a plate castor by three bolts only. Never skimp on the mounting base.
Remember - if the castor does not stay mounted squarely, it will not swivel freely. Medium duty castors (L, K, M & F series) are often mounted into tubular legs. But again, it is important that these legs stay vertical. We recommend that the leg never extend more than 125mm (5”) below the nearest support, and (apart from the lightest uses), the tube should be 1.4mm (17G) thick or more. Thinner guages often split. If you wish to use lighted gauge in the rest of the trolley, insert a sleeve for at least 150, (6”) where the castor is mounted.
Never put a round expanding fitting into a square tube. The first time a trolley hits a bump, the tube will elongate, and the castor will fall out. We do have square fittings, and ask that you use them. If for some reason you need to put round into square, then weld an insert sleeve of round tube (remember - our smallest fitting needs 3/4”ID). When using Directional Lock (DL type Castors) it is best to use the solid swivel stem (A type) and weld or bolt it in - screwed types can become misaligned. To achieve the best performance from the larger 175 (7”) and 200mm (8”) castors, use solid stems.
When fitting expanding stem castors, make sure that the fitting is fully inserted into the tube, with the tube firmly down onto the castor head rivet, before tightening it up (you may have to remove some of the burr on the inside of the tube before you try to push the fitting in). After making sure the weld on the inside of the tube is not excessive, align it with one of the slots down the outside fo the adaptor fitting. Put the fitting into the tube ALL THE WAY, then put some sideways pressure on to it to help the fittings grip, then tighten the stem bolt firmly. Tighten, but NOT over tight, or you will make it hard to remove later.
Never try to get the unevenness out of a warped trolley by half inserting fittings. You can get up to 8mm (5/16”) of adjustment with washers, or an offcut of tube tightly jammed between leg and castor - but do not let it float. Tighten tubular fittings firmly, but do not over-tighten. You should retighten castors after 3 months of use, and annually after that. We recommend ‘3 finger’ tightness, ie the amount of torque you can get onto a standard spanner using your 3 middle fingers. (Ask for our separate detailed ‘Fitting Instruction’ sheet.) Under average conditions of intermittent use, FALLSHAW castors will run for 5 years without maintenance. If the castors are in constant use, this reduces to 1 year.
Greasing: Grease in both the swivel and the wheel serves three purposes; a) it prevents rusting of the balls and raceways; b) prevents galling; c) it reduces noise. It does not need a lot of grease to do this. Too much is unsightly and only attracts dust. A liberal smear is all that is needed. If you only have a few castors to grease, use your finger to apply the grease, then wipe off the excess with a rag or use a needle tip grease gun. If you have many of them we suggest the following: • Turn the trolley upside down and remove the wheels. • Re-grease the head, either through the grease nipple if fitted, or by a needletip fitting on a grease gun. You will need to lift the seal on the heavier range of castors with a sharp pointed screwdriver. Two full squirts are usually adequate, but make sure enough grease gets through to the centre so it can descend to the bottom race. • Check the wear of the axle bushing. Reuse if not heavily worn, otherwise replace. Smear about a teaspoon of grease along the inside of the wheel bearing with your finger, taking care to force the grease up into the rollers and reassemble. • Be careful of the lip seal on the wheel as you reinsert the axle bushing into the roller bearing wheels. Make sure the axle bushing is clean as you reinsert it. • Reassemble the wheel into the castor. Replace washer where fitted. A drop of Locktite High Assembly Strength solution on the axle thread is a good precaution. • Use a No.2 bearing grease (not sodium based). Swivels: All castors have the races staked during assembly so therefore do not requre any adjustment throughout their operating life. Wheel Bearings: Any slackness present in plain bearings or roller bearings can often be improved by replacing the axle bushing. If necessary, the plain or roller bearings can be replaced as well. Often simply re-greasing B type bearings is enough, though they can also be replaced if necessary. Sealed precision Q type bearings seldom wear sufficiently enough to need attention. Wheels: Polyurethane wheels usually outlast any trolley to which they are fitted, such is the wear resistance of polyurethane. In general, all our wheels are designed with adequate tread thickness for long life and allow for replacement rather than repair. Tube Fittings: It is advisable that any tube fitting on expanding stem castors be checked after the first 3 months, and then yearly to make sure the tube fitting is fully and firmly into the tube and the tightening nut is firmly but not over tightened.
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