Home › Forums › Free Flight › Old Time Rubber › Keil Kraft Senator
- This topic has 7 replies, 3 voices, and was last updated 13 years, 11 months ago by JIM MOSELEY.
03/28/2009 at 2:17 pm #41092AnonymousInactive
I have just completed my second KK Senator and taken care to build the tail end light.The C of G with 35g of rubber is still an inch too rearward.It is shown as about 60% on the plan.I am loath to add weight to the nose as this will increase the total weight and reduce performance.Are there any experienced Senator flyers out there? Will I get by with reduced decalage at 70% CofG?
My first Senator flew OK but had no D/T and was too heavy.Getting a 2 min max out of it was near impossible.
03/28/2009 at 2:47 pm #47184AnonymousInactive
Photo attached03/28/2009 at 5:21 pm #47185JIM MOSELEYParticipant
I’ve been flying Senators for many years, and run the Postal as an aside.
70% is about right and you shouldn’t need any rigging change.
What strandage are you using with 35gms? I now fly 30gms with 6x 1/4″ or equivalent … similar strands with 35gms have been discarded due to bunching at the peg03/28/2009 at 9:42 pm #47186gosParticipant
I’m with Jim. 30 grams is plenty. 6×1/4, 8×3/16 or 12×1/8.03/29/2009 at 7:06 am #47187AnonymousInactive
That is very helpful.If I reduce the rubber to 30g the CofG will be better.I am just off for the first flight.There seems to be no wind today.Do you braid your motors? More details please.
Sorry the photo did not work.I have hinged the tail end of the fuselage for D/T.Maybe a wing D/T would be lighter and less weight at the tail end.I am using a Tomy timer at the nose end.03/29/2009 at 8:44 am #47188gosParticipant
Some (Jim, etc) use a spring and stop on the prop. shaft to stop them unwinding and flopping around in the fuselage…….bad for glide CG position, but I like to braid my motors by winding on turns before the motor is fully made up.
If you say used 8 strands of 3/16 then at 4 strands wind about 50 or so turns on it and then loop it over to make the finished 8 strands.
I place a small rubber band around each end first then a band around the lot.
The motor will wind around its self to shorten. Clear as MUD?????
04/02/2009 at 10:07 pm #47189AnonymousInactive
First flight was a spiral in to the left,but this was cured with some right thrust.I have not reduced the rubber to 30g yet but the 35g braided works OK.I am using 6 strands of 1/4″. It is flying much better than my first model. I hope to have it trimmed for mini-vintage at Middle Wallop over Easter.
It seems a long way removed from F1G and all that carbon.
I reinforced the spar under the rubber bands that hold on the wing with some vertical webbing.It enables me to attach the wing without breaking the 1/16″ balsa spars.I think spruce spars would have been better.The weight gain would have been minimal.
As stated previously,the C/G seems spot on at 70%
I have 4 grub screws in the nose to adjust side and down thrust.It is much easier than shimming with balsa.
Does anyone know of a link describing a wing D/T mechanism?04/03/2009 at 2:56 am #47190JIM MOSELEYParticipant
>Does anyone know of a link describing a wing D/T mechanism?
Doc – email me! I need your address to send pics, etc.
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