3/16 Carbon Fiber Pushrods

I am currently building an Impact with a Ro-Jett 65. Could anyone tell me if the Ball Link System with the 3/16” carbon fiber push rod Tom’s Building Service sells is strong enough for this plane? I have concerns about the threaded inserts breaking at the threads.

Well, My Impact from Ultra Hobbies has the Tom Moris system. It does look frail at the joint of the threads and the insert, but the metal is high strength. I'm more concerned about the insert pulling out of the push rod. If this new plane lasts as long as my old one, I'll keep using the ball links/ carbon rod, etc. If not I'll go back to the old system. Wish us luck, best regards,

My plane I am flying now has at least 3000 flights with the same system in it and it is fine. I expect 3000 more. I do not advocate it but mine are glued with CA and then tied with carbon tow and CA from the outside as well.
Richard Oliver

LAST EDITED ON Aug-14-03 AT 08:44 AM (CDT)
 
>Well, My Impact from Ultra Hobbies has the Tom Moris system.
>It does look frail at the joint of the threads and the
>insert, but the metal is high strength.

Titanium in fact.

Noel Dindrak tests showed that the Central Hobbies system will support well over 400 lbs. Actually, it never failed in his tests.

Ball link systems, compared to everything that came before it, is like comparing persimmon drivers to titanium. I liked persimmon, but there is no question in my mind which performs better.

My Legacy has Tom's system, complete with bellcrank. My only worry is that I buried the bellcrank in the fuselage before I heard about beefing up the ends. Tom now suggests you wrap the ends with wire to keep the rod from splitting. I am not going to cut into the Legacy as many High time 60 ships are out there without the ends wrapped so I will take the chance.. Someday (if I ever get it painted) I will report on the outcome.. Thinking it is a pretty safe bet..

>I am currently building an Impact with a Ro-Jett 65. Could
>anyone tell me if the Ball Link System with the 3/16” carbon
>fiber push rod Tom’s Building Service sells is strong enough
>for this plane? I have concerns about the threaded inserts
>breaking at the threads.
>
>Don
>
Hi Don, There should be no problem at all as to strength. Clean the inside of the cf tube with acetone, and scratch the inner surface slightly. I use a new 6-32 bolt to break the "glaze".
I would recomend only j b weld to attach, but others have used various adhesives. I wrap the end of the tube, overlapping the shoulder portion of the threaded insert, with CF mat attached with CYA after the jb weld has cured. Unlees the part has an unseen defect, they are more than adequate for the job.
Bill

>I am currently building an Impact with a Ro-Jett 65. Could
>anyone tell me if the Ball Link System with the 3/16” carbon
>fiber push rod Tom’s Building Service sells is strong enough
>for this plane? I have concerns about the threaded inserts
>breaking at the threads.
>
>Don
>
The system is plenty strong, when I decided to use it I had a long conversation with Tom about it's development. It's success is world wide. Follow Bill's advise along with instructions Tom’s sends. I re-printed Tom's assembly article in the last issue of stunt news (with his permission). If you’re not a member I would highly suggest doing so. You’ll get six issues of great building advice and interesting reading.

Thanks All, I go ahead and order the stuff.
Thanks Larry, I'm not a member but I found the web site and printed the form, I'll join right away.

Rather than wrap the tube, I slide an appropriate size piece of aluminum tubing about 1/2" long over the CF tube, install the ends, and then slide the aluminum into place with a bit of epoxy to hold it. Makes a very tidy end.

I have seen this aluminum tube method on three planes at Brodak's Fly In this June. Neat and clean. My next plane will have this too. I am a copy cat and use only the best ideas I can steal.

Hey KD!,

Great tip on the aluminum tubing! I sleeved a rod for my Cardinal last evening and was very impressed with the out come. It takes a slight bit of sanding on the rods I use (.196") for KS 7/32" tubing to fit nicely. It sure is a "sanitary" detail. Way Zoot!

Many Thanks and Nitro Fumes!.......Hib

Dang, I wish I could remember who I stole the idea from so I could attribute it.....
Kelvin