When using the grease gun bear in mind that it is better to lubricate a little and often rather than to neglect this attention for a considerable time and then over-lubricate. In very wet or dirty conditions, lubrication of the various points should be carried out more liberally. Should it be found that for some reason or another grease will not enter a bearing but escapes between the grease gun nozzle and the nipple, this can usually be prevented by inserting a piece of clean rag between the nipple and the grease gun nozzle. The rag forms an effective seal and will usually prevent all leakage but will allow grease to pass freely into the nipple. Do not use heavier grades of grease than are specified as there is a danger that the various bearings and bushes may not receive a proper supply due to the grease choking the passages, etc. When greasing girder fork spindles it is advantageous to support the machine with the front wheel off the ground to get the grease between surfaces normally in hard contact.