sjhanc

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I have this Zinger 4 blade 22-16 prop with a spare set of 24-16 blades. I painted the 22-16 blades and applied nomenclature and Hamilton standard decals as you see in the picture. The prop was balanced by applying GOOP to the light blade hub. I flew the 22-16 for one test flight on my electric 29.5 lb. TF GS P-51B, then installed a 22.6-18 Varioprop next to compare flight characteristics and performance between the two brands. The electric Varioprop won on lower current draw in level flight so I went on to fly many flights with the electric-Varioprop combination. Different blade combinations could be made using the DB hub for a drill jig and cutting four 2-blade props to fit. It is possible that Dave Drown products could supply replacement blades if they are still in business but it was my understanding that each 4 blade prop was custom made-to-order.

Flying performance with the Zinger was good (85+ mph) but the Varioprop suited my B model the best so this Zinger has been a wall ornament after the one test flight. My best estimate of a suitable engine for this prop is a 100-120cc gas engine is required for best performance. Engines like a DA 85 or ZDZ 80-90 would give scale like flight performance with top speeds of over 75-80 mph in level flight. The electric power combo reached 100-105 mph in level flight but continuous current draw (130-140 amps) was too high for the electric motor. Takeoff current draw reached 165 amps until the gear was retracted then dropped to the level flight range.

If anyone is interested I will post it for sale (bids) in the classifieds. I cut up an old Dave brown 5 inch P-51 spinner for it and also had to enlarge the hub's front prop plate hole to be able to be able to use a countersunk prop nut and washer as the hub is thick and normal engine or motor shaft length is too short for the stock prop nut and washer. I think I still have the modified prop nut and washer, but it would take a search to find them. The Dave Brown Products nut I used had a 10-1.25 mm thread and was turned down by a private machine shop to allow the washer to fit high on the nut's shank and is a tight fit inside the prop hub's front plate. The prop came to me assembled by Dave Brown products in a large shipping container and I have not taken it apart. It could be dissembled for easier and cheaper shipping. I have recently sold the Zinger 4 blade to someone who want to try it on a large gas engine.