Aluminum spreader bases are the interface between the flat base of the spreaders and the curved side of the mast. They are also thinner at the top than the bottom to accommodate the angle of the spreader above horizontal.
Caution! Customers report finding remnants of broken spreader bases on deck and not knowing what they are. I can easily envision a helpful crew hosing down the deck after a rousing sail. Small pieces of the spreader base could easily be washed overboard without anyone noticing.
Inspecting the spreader bases and spreader bar should be on your annual standing rigging inspection checklist.
It is critical these bases be in place. Without them, the compression load from the spreader will be applied to just one point on the side of the mast rather than being distributed across the entire spreader base. Under the best of circumstances, accelerated wear will occur at this point. In the worst case scenario, high load at the point of contact could deform the side of the mast causing catastrophic failure.
• Catalina 34
• Catalina 36
Important note: The original castings varied substantially from one set to the next.
Our replacements are machined precisely on a CNC machine. Since there is slight variation in the mast extrusion from one to the next, some sanding of the inboard surface of the spreader bases will likely be required to create an exact match to the contour of your mast.
In addition, the thickness of the original cast parts varied. In fact, when assembling the mast, Catalina's staff was required to sort through their inventory to choose two of the same thickness for use on your mast. Our replacements are machined to the median thickness of the original castings. If the thickness is too different from your old parts, it may be necessary to purchase a new spreader bar, #F8115, in order to re-drill the bar as needed to match the existing holes in your spreaders. See "May we also suggest" below for the spreader bar.
We suggest you purchase the spreader bar so you have it if needed. The spreader bar is a stock, but low sales volume, part. As such you always have 30 days during which it may be returned if it is not needed. It must be in its original pristine, un-drilled condition and returned within 30 days to receive credit.