The bottom 2" pipe is the full 21' length, and the top 1-1/2" pipe is about 17' long to give the total of 36' with the 2' overlap. The drawing to the left (not to scale) shows the base and some of the details of the assembly. The base is made of another 21' piece of 2" pipe cut in half to make a 10-1/2' long base unit. The pipes are spaced a little more than one pipe diameter apart and secured by welding 3/16" X 2" steel strap between them. The mast pivots on a 3/8 X 8" bolt at the base midpoint just above ground level (dashed rectangle). This leaves about 5' of base both above and below ground.
To achieve this we studied the gene expression profile (GEP) of purified mast cells (with purities greater than 95-98 percent) of bone marrow samples.
The great difficulty involved in this work was precisely to obtain the biological material, because the mast cells do not spend much time in the bone marrow of healthy individuals or patients with indolent forms. (Mast Cells in bone marrow are usually very rare, typically less than per cent of the bone marrow cells).
Even in aggressive forms it is rare that the percentage exceeds 1-3 percent. For this reason, the selection of patients and obtaining the biological material (RNA purified mast cells) took over six years of work.
Many people may wonder why some of these differences matter. One would think the only important aspect of a forklift mast is how high it can lift. However, the lowered height is sometimes just as crucial as the maximum lift height. If your application requires you to take a load through a door or your facility has any overhead restrictions, the down height is very important. Can you make it through all your doors? One step further, can you make it through your doors with your load raised 6″? Full free lift can make that difference when loading and unloading trucks on a dock, in a container, etc…