Re-building some basket case Bantams from Ebay updated 08/12/2012
In June 2012 I bid for and won a pair of engines. One of those engines was a Bantam 19 in exquisite condition. I have also aquired a number of basket case Bantams and I now plan to rebuild as many of them to running condition as I can.
I will keep a blog of progress here.
First: strip down the engines:-
The engine parts are well used and some of them will need to have significant remedial work to reclaim them. One of the cylinders has a bad dent in the bottom of the cylinder, the result of a conrod break. The only backplate assy has been hacked probably to try to extract more performance from the engine. One of the crankcases has had its mounting lugs cut off and one of the other complete crankcases has a backplate stud broken off flush and this will take some careful work to remove. There should be enough parts to build one complete timer assy. I will probably have to make at least one and probably two new pistons. Of the two crankshafts one has no timer cam machined and so will be used for a glow ign version. One of the good crankcases is magnesium and one is aluminimum. The aluminum case weighs 6.2 gm more than the magnesium one.
Another Ebay aquisition. I will probably use one of the "good" crankcases to replace this broken one. The rest of the engine looks to be in very good condition.
On 8th December 2012 I received another consignment of Bamtam parts bought via Ebay. The description was as follows :- "Box Full Of 1940's Bantam Control Line Airplane Motor Parts, They Appear Unused Just Dusty, All Of The Things I am Listing Were The Collection and Stock Of A Long Ago Hobby Shop"
I have inspected and cleaned these parts and it looks as though a lot of the parts are unused. The pistons don't seem to have been fitted to cylinders, 2 of the crankcases are only part machined. All of the cylinders are perfect with the exception of one that has a drill broken off in the mounting hole (I expect that I can deal with this and retap the hole)
So a summary of the parts in the latest aquisition.
5 off crankcases 4 are aluminimum and 1 is magnesium. 2 need machining and 1 (the magnesium one) needs a good clean. There was a 6th case but it is damaged beyond repair.
7 off cylinders. all clean and undamaged. They may need lapping to finish the bores and one needs a broken drill tip removing and the holes tapping.
4 off crankshafts all good and usable for spark ignition.
7 off pistons. all machined but will need lapping to size for cylinders.
7 off conrods. There appears to be 2 different designs so a bit of detective work needed.
9 off timing disks. Some are a bit rusty but it looks like surface rust only
3 off backplate units. There were also 3 damaged one of which one might be reclaimable.
2 off prop drivers. I can make these easily.
Engine numbers:-
0029258 - complete - broken lug magnesium case
007076 - complete unrun example non-strap case
32580 -aluminium case only
0005014 -magnesium case non-strap case unfinished machining