pipe stress: tube stress calculator flexpipe starlight focuser patent US6069754A Well, any focuser (even starlight) can be broken if you use it beyond the payload limit, or mis-use. So don't be sold by those over-engineering marketing broken/worn brass brake : Inside the pinion block, there is a brass brake lever in which holds the pinion shaft. The pinion shaft of the focuser sits inside 2 u-shaped openings in the brake lever. When the brake thumb screw is tightened, pressure is applied on the entire length of the brake lever and not on just 1 spot where the thumb screw touches the pinion shaft. The problem is that the u-shaped openings of the brake lever were completely worn away in which allowed the teeth of the pinion shaft to wear a groove on the flat of the brake lever and this allowed brass shavings to get into the reduction assembly. If Starlight Instruments was contacted early on about any questions regarding the focuser, Starl...