Hi Rob,
The advice that Nigel passed on was essentially not to "trust" any work the previous owners carried out. While your refurbish work was over 10 years ago compared with my work here, obviously there are significant parallels. However I am finding it all quite satisfying from an engineering perspective. If financially viable I would like to "do" another. Apart from the UC rod ends, an issue which did really worry me (hence this reply) related to the tailplane AD. The front pin (that was in the AC when I picked it up) didn't fit the (real expensive) replacement rod end. It would seem it the HT original was replaced with a mild steeI one (presumably in Thailand) . Fortunatly the correct pin was available from Diamond so all OK, but it could be possible that some other ex Thai H36's had similar pins. I guess if a U/C rod end broke, a landing could be tricky but if the tailplane comes off in flight things could get real dodgy. Another problem was all the nylon fittings ... rudder pulleys behind the seat and the bearing sets on the wings supporting the aileron control push rods. In all cases, the nylon (being slightly hydroscopic and exposed to Thai weather) had expanded. The rudder pulleys were jammed in their mounting brackets and all the bearings in the wing (older model with 5 sets per wing) were seized (30 bearings in all. Replacing them was a major mission. The Diamond sourced replacements were "proper" bearings with a nylon "tyre" rather than the entire outer being nylon. (identical to the DA40 elevator bearings) The other Dimona here in NZ (which I maintain) has very stiff, sticking ailerons in flight which makes flying it not real pleasant. Nigel B has explained the change in aileron design with later A/C's. However I am hoping that the new bearings will sort out that problem . The old design does use centering springs which presumably will tend to reduce the "feel" of the ailerons but going well, no "sticking" The H-36 here also has the U/C with the serial no of your H36. That does worry me a little as it seems this one had an engine failure in Thailand and landed in a paddy field, busting its U/C (in the centre) That does account for some repairs we had to do around the attach points (and internal skins) and the bent rod ends. "your" U/C has cleaned up well and there is no sign of any repairs but there is still the lingering question of why it was replaced in the first place. THe little ship here is looking quite nice now and I am really looking forward to getting it in the air. I have tried to keep it as original as possible. The exceptions are .. electronic tach, USB port for Ipad power, GPS, Dittel com and a microair transponder. Of interest, the L2400 from the Stemme which I installed in a Grob 109A over here is going really well. I think it has now over 200 hrs of trouble free operation. Keeping those little engines cool seems the secret. It was not a cheap exercise though. The NZ CAA were at that time charging $90.00 per hour for any inspection work (which I thought was rather high) but now are charging $240 per hr. Best regards Ian Williams New Zealand From: [email protected] [mailto:[email protected]] On Behalf Of Rob Thompson Sent: Thursday, 15 August 2013 10:00 p.m. To: [email protected] Subject: Re: [DOG mailing list] H36 undercarriage When Nigel and I restored the three Thai Dimonas in 2002 we replaced the undercarriage rod ends. Most of the the old ones were bent and they must have been original...we had to cut out the panels to gain access. My question is....do you really want a high tensile rod end that tends to snap or is it better to have one that bends? This is a question that is right up Nigel's alley of expertise. The flask is under the seat pan...can't remember which side...I think passenger. Poke a mirror through the inspection panels and look rearwards and you will see it. cheers Rob Rob Thompson mobile 0429 493828 ......................................... _____ From: Ian Williams <[email protected]> To: "[email protected]" <[email protected]> Sent: Thursday, 15 August 2013 7:22 PM Subject: Re: [DOG mailing list] H36 undercarriage Hi Ian, Same here. The ones here were bent indi ating they weren't HT. RickFisher sourced the right ones from Germany for me. there were also other rather dodgy issues as well but all OK now. Nigel B's advice dead right. A question for you Dimona Technocrats however. ..Where the hell is the flask For the VSI stashed. Ian Williams Sent from my iPhone On 15/08/2013, at 20:42, Ian Mc Phee <[email protected]> wrote: Friend with early Thai h36 found an undercart ball rod end broke after landing but zero damage luckily. He fount the Thai we assume used non standard ball rod ends with no untreated shank. The correct ball rod ends are made by hirshmann in Germany and have a X indicating they are high tension ball rod ends. Lesson you can not trust Thai airforce or was it Geoff Edwards?? the guy that brought them in. When I was at Archer field there were broken undercarriage everywhere. If ball rod ends have been changed then there should be a repair in the floor when they have been removed. I think I have read somewhere after hard broken undercart either ball rod ends are to be replaced or are the brackets to be replaced. I would say it is ball rod ends. May be worth a look and always do perfect landings. Ian mcphee ..
