GP J-3 Cub right thrust?
 

Hi All, I mounted my engine on the Cub J-3 per directions using the supplied motor mount and notice there is a little right thrust, is this normal? does the J-3 have right thrust? I didn't measure the amount, but there is a little. Thanks...Bill

RE: GP J-3 Cub right thrust?
 

Hi Bill,

I have been following (and replying to) some of the GP J3 Cub posts as I am also just beginning to build mine. I noticed a couple of days ago that mine also has quite a bit of right thrust. I did not take an exact measurement yet, however, it looks to be about 2 - 2.5 degrees. Unfortunately I cannot answer your question - I am not that experienced with cubs and I do not know if this is correct. I did go to the GP website and found no listing for the ARF with respect to right thrust, but they do list 2 degrees as the right thrust for their 60 size kit. Hope this helps. I will be curious to see what some of the more experienced members say in their replies to your post.

I am with TONJ are you with LVRC Club?

Regards,

Steve

RE: GP J-3 Cub right thrust?
 

Yup! LVRC and Tri County Wingsnappers in Lenhartsville, Pa. Rod Maier of LV tells me the Cub requires approx. 2 deg r-th so we're ok! I question the method the aileron control horns are attached, looks inadequate, but will try it. I'll be using the DuBro adustable horns for the rudder and elevator and I rigged up flex cable and a ball link for the throttle. I am using an OS LA 65 for starters, maybe later a 4 cycle. The LA requires a ball link to off set the tightness of the throttle arm. I'm medium glassing the bottom of the wing whenever I get around to epoxying it together. Get to me off list if you wish and we can trade ideas! Bill

RE: GP J-3 Cub right thrust?
 

Have you tried to contact hobby services ?... they are very helpful and will assist you if they can. I have 2 GP cub arf's and I have a OS 70 fs in one, At first I had some problems with the plane trying to right turn as soon as power was applied even with full left rudder I checked the wing incidence and the alignment again everything was straight I also checked the engine's angle of thrust I did notice that there was some right thrust but I don't remember how much.( It's was 2 year's ago )..After flying the plane a few times I noticed that when the engine @ the top of the compression stroke the prop was at about 12 o'clock so when the engine fired the weight of the prop tip was at 9-10 o'clock position I changed the position of the prop 90 deg clockwise and the plane tracks straight without any right tracking. I did'nt like the plane at first now it is one of my favorite's . It is on ski's now and will be on float's this summer...The la 65 you are going to use will be sweet and I think you will like the plane ...good luck and have fun ...JW

RE: GP J-3 Cub right thrust?
 

Mr. Autoguns, Thanks I researched this and the r thrust is built in and normal. Are you into shooting? (autoguns?) I shoot Bullseye competition and other disciplines as well. Bill

RE: GP J-3 Cub right thrust?
 

Hi Bill ,Ya I'm into gun's to say the least I have built some good shooter's mainly in .223 .308 & 50 bmg...One of the REM .223 PSS's shot so good the Anchorage PD wanted it for there CIRT team I shortened it from 26" to 20" and threaded it for a can ,It's very quiet with 3000' per second ammo and with sub sonic ammo it sound's like a pellet gun ...I also do alot of work on class 3 gun's (such as machine gun's supressor's and SBR/SBS ecc.) it has been a hobby of mine sense 1983.... Lately it has taken a back seat to plane's LOL...so many thing's to do,so little time....JW

RE: GP J-3 Cub right thrust?
 

Time...I know what you mean. I shot Bullseye for 10 yrs. but have quit competing due to work, time, etc. but I still shoot weekly for practice. In fact my buddy from work and I spent the afternoon at the range today, I have a Les Baer done up Colt 1911 (45 ACP), and brought the Ruger Super Blackhawk 44 mag. for some exercise, also took an SKS just for kicks. Also a couple of 22s, a Makarov and some other toys. I don't do much shooting during the flying season, but when it gets cold and snowy, the planes go on the rack and out come the irons! Bill

RE: GP J-3 Cub right thrust?
 

Yes, the cub needs about 2 or 3 degrees of right thrust. This is true for most planes with an airfoil wing.

RE: GP J-3 Cub right thrust?
 

Thank you all for the right thrust information on my J-3 ARF. Now if I can only finish it, and if all this lousy snow will melt and warm up! Bill

RE: GP J-3 Cub right thrust?
 

I know what you mean , I havent been out shooting much lately , I have to get back into it before summer hit's ...We like to go out and shoot at ice burg's, that is allot of fun ...M16 c-beta mag with tracer's is alway's a crowd pleaser...Here is a couple of pic's of mt m16 w/can Rem PSS w/can and my springfeild m-14 e2...Talking to you i'm gettin the bug again ....LOL ... The PSS is the one I did the machine work on ....Note the guard dog ...He's blind ...Cya ....JW