Home › Forums › Free Flight › The Engine Shop › Steel Fin OS Max .19
- This topic has 6 replies, 5 voices, and was last updated 16 years ago by gos.
03/20/2007 at 3:54 am #40609AnonymousInactive
I just picked up a new in Box Max .19 with steel fin. Looks like late production model of steel fin engines. Looks just like my Max .15 111 engines. It just has OS Max .19 on side. Anybody run one of these and what ship you used it in?
Cheers,Dan03/20/2007 at 10:43 am #44171AnonymousInactive
OS19, great engine and will happily run on 15 -20% nitro and no synthetic oil. Bit more power than the 15 and suitable for any of the class A gas designs up to 500 squares of wing area. Not quite sure of the vintage possibly 1958-59 and only one run before switching to the later 20 size
Ployd03/20/2007 at 11:32 am #44172Dean McGinnesParticipant
That is my number one Class A Nos Gas engine!! I have 3. Very, very strong. Bob Mattes has a really great service. He will make you a head to convert to the Bullet-Proof Nelson HD plug, fit the crank, and blueprint the timing.
It will out pull my Greenless Head .23 on my Bird 525.03/20/2007 at 10:38 pm #44173AnonymousInactive
Thanks guys sounds good. I also got a fine Veco plain bearing Veco .19. Aewsome compression I hear these go pretty good to.
03/21/2007 at 12:28 am #44174Glenn SchneiderParticipant
It would be very interesting to compare the Veco to the O.S. head to head, same day same fuel, same plug, same prop and a tach. Both are top notch nos engines in that size. My O.S. is going into a Lucky Lindy, yet unrun but I’ve seen the same setup perform very well. Any of the FAI models of the era would probably do fine including the Lindy, Crescendo or a Swiss Miss.
The shaft thread on the O.S. is very strange, turns out to be a 7/32-32. I’m not sure if a 12-32 is the same. Tower Hobbies has spinner nuts to fit in colors yet, Goldberg brand.
What are the favorite props for the O.S.?
Thermals, Glenn03/21/2007 at 11:31 am #44175Dean McGinnesParticipant
The thread is 5.5 X .8 mm., which is a non-standard thread. 12 X 32 is a good match. I did not know spinner nuts were available. Great. I had to make my own tap to make mine. Then discovered a 12 X 32 on the Grainger web site!!
Mine is pulling a 9 X 4 APC in order to “match” my K&B .23. Turning an 8 X 4 APC, it accelerates so fast the model goes off pattern. Still working on that one. 🙂03/22/2007 at 7:25 am #44176gosParticipant
Just further to 19s in your NOS class, we simply have vintage here in OZ pre. 1955.
I have a Swiss Miss that flew well with a K&B 15, as per the original that got second in the 1954 World Champs, but I always felt it was underpowered, so I have put a K&B 19 in it for more grunt.
I thought about an 8×4 APC being a bit small, and a 9×4 being a bit big, so as I had a Taipan 9×4 cut down to 8×4 in stock, that’s what I have stuck on it
a ‘big’ 8×4, but as yet unflown, so I will be interested to see how your 19s go on what props.
- You must be logged in to reply to this topic.