Hi Lasse, I have not the experience with the H-36 like the Australian dudes, but I am working on a H-36 at the moment. It is an Thai Air Force one, imported into New Zealand some time ago. (from Australia)
There have been 2 issues which I think are worthy to discuss. The first is the bearings inside the wing. There are 5 linear type bearings in each wing supporting the aileron push rods. Each bearing consists of a 3 piece bracket with 3 ball bearings pointing inwards, in contact with the push rod. The problem is the early model bearings have no steel outer race... Just have a nylon (may be Teflon) outer race. Over time, these bearings seize. I have replaced all 10 which meant cutting significant holes in the wing to replace them. The replacement bearing assys were supplied by Diamond and included stainless 3 piece bracket, and the new bearings had a modified steel outer with a nylon "tyre" ... get the picture. It was a mission but I think well worth the effort. They are REAL smooth now. The second thing is the aileron attachment. They are pop riveted on with a large no of rivets ... Check that there is no corrosion and all rivet heads are intact. The NZ Gliding Engineering chief (Roger Harris) suggested checking the wing bearings because the wing "rattled" when shaken ... was the aileron push rods rattling against the bearings. His concern was that if too loose, could result in a flutter problem. Hope that is some help Ian Williams Drury Auckland New Zealand -----Original Message----- From: Lasse Schmidt [mailto:[email protected]] Sent: Friday, 29 January 2010 10:32 a.m. To: [email protected] Subject: [DOG mailing list] H36 spung tailwheel I forgot the link, sorry about that. http://cgi.ebay.com.sg/Hoffmann-H-36-Dimona-Wood-Desktop-Airplane-Model_W0QQ itemZ380121990970QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item588109473a Lasse Schmidt +46 (0)70-28 32 660 Upplevelseakuten AB Tullhus 1, Skeppsbron 111 30 Stockholm www.upplevelsepresent.se ________________________________________ Från: Lasse Schmidt [[email protected]] Skickat: den 28 januari 2010 22:30 Till: [email protected] Ämne: [DOG mailing list] H36 spung tailwheel Hi guys! This group is really fantastic. Thanks for all the tips and ideas. While checking all the service bulletins I discovered that the individual i am planning to buy was exepted (serial 36117) from bulletin No. 22 (the one about the horizontal stabilizer safety mounting). It would be interesting to know why :). Does any of you fold the wings after each flight? How long does it take to fold the wings, can it be made by one man or is two persons needed? Interesting about the tailwheels, I think I have to get my bird home to start with before starting on all the mods. By the way, found this H36 model on ebay - someone is really bad at photoshop... Cheers Lasse Schmidt +46 (0)70-28 32 660 Upplevelseakuten AB Tullhus 1, Skeppsbron 111 30 Stockholm www.upplevelsepresent.se ________________________________________ Från: Rob Thompson [[email protected]] Skickat: den 28 januari 2010 22:15 Till: [email protected] Ämne: Re: [DOG mailing list] H36 spung tailwheel What about we pay someone from nearby to Bacchus with drafting skills to draw plans (including shop drawings) from Dave Goldsmith's sprung tailwheel? The plans for the spindle part that fits into the fuselage can be done from any Dimona at annual inspection time so we won't have to pull Dave's apart. Then get the steel parts cut from appropriate grade metal, pay someone to do any necessary machining and get the lot welded by an aviation welder. Maybe we would have to make some sort of a jig to send the bits to the welder in..maybe not. >From the experience Nigel and I had refurbishing the 3 dimonas and the way Hoffman sourced components I reckon it's a good bet that the rubber blocks are an off the shelf part. cheers Rob Thompson PO Box 129, Lawson, NSW, 2783. mobile 0429 493828 ............................................. ________________________________ From: STO Airworthiness <[email protected]> To: [email protected] Sent: Thu, 28 January, 2010 1:50:52 PM Subject: RE: [DOG mailing list] H36 spung tailwheel Hi All, I would be interested in fitting the sprung unit. Probably will add a good kilo or so, which will equate to a min pilot weight increase of about 7 kgs. Dave Goldsmith's H-36 MkII VH-GFG also has the sprung tailwheel. It lives between Bacchus Marsh & Bendigo. >From a GFA airworthiness point of view, exchange of the rigid wheel for the sprung one would not constitute a mod if the factory parts are used, but should we decide to build them locally a mod would be required for each aircraft to which the new assembly is fitted. This is easily achieved; we have done it before with oil filter installations. Regards JGV Senior Technical Officer, Airworthiness GLIDING FEDERATION of AUSTRALIA INC. [email protected] ---------------------------------------------------------------------- The Gliding Federation of Australia Inc invites you to visit the web site www.gfa.org.au newcomers to gliding and soaring are invited to visit www.soaring.org.au ---------------------------------------------------------------------------- --------------------------------------- This email transmission may contain confidential or privileged information that is intended only for the individual or entity named in the email address. If you are not the intended recipient, please be aware that any disclosure, copying, distribution or reliance upon the contents of this email is strictly prohibited ________________________________ From: John C [mailto:[email protected]] Sent: Thursday, 28 January 2010 12:00 PM To: [email protected] Subject: Re: [DOG mailing list] H36 spung tailwheel The only H36 with a sprung tailwheel that I know of in Australia is GJD owned by John Mason. The sprining consists of two rubber blocks which take the bumps out of the tail compared to the non sprung version. It does raise the tail slightly. There is a drawing on page 4.10 in the H36 parts catalogue. I did replace the top section on GJD when I imported it as there was a very slight bend in the vertical spindle and this caused tailwheel shimmy. The faulty part is still in the workshop. There's no place like cloudbase. John Callahan. ----- Original Message ----- From: John Mason<mailto:[email protected]> To: [email protected]<mailto:[email protected]> Sent: Thursday, January 28, 2010 11:09 AM Subject: Re: [DOG mailing list] H36 spung tailwheel I'd certainly be interested in that... John Mason - GJD ----- Original Message ----- From: Rob Thompson<mailto:[email protected]> To: [email protected]<mailto:[email protected]> Sent: Thursday, January 28, 2010 11:03 AM Subject: [DOG mailing list] H36 spung tailwheel I'm keen on the idea of getting a sprung tailwheel on our H36 - the rigid one is not at all good on rough surfaces. I think the sprung wheels may also reduce the "bunny hopping" on rough runways....can anyone enlighten me as to whether this is the case or not? Last time I saw a sprung one I didn't think it would be particularly difficult or costly to manufacture - perhaps we could get some plans drafted from one of the dimonas with a sprung wheel and see about getting a few made up with appropriate approvals. How many of you would be interested? cheers Rob PO Box 129, Lawson, NSW, 2783. mobile ............................................. ________________________________ From: Ian Mc Phee <[email protected]> To: [email protected] Sent: Wed, 27 January, 2010 11:39:22 PM Subject: Re: [DOG mailing list] Dimona 1984 Interesting about tail wheel mod from Michael - sure gives smoother ride. You mention the heads/valves lasting only 300hrs. I would recommend to all analysis of exhaust at FULL POWER with lamdameter etc. You may find it is running slightly lean on full power (actually plugs look OK) but gas analysis does not lie. More recently i have been using digital CHT and you can really see what is happening. I set them up so full power CHT rises to about 170degC then very slowly falls. If you bring throttle back just a bit in revs CHT will quickly rise to 180degC and beyond. This proves to me you are running rich on full power- also confirmed on EGT. To achieve this it may be necessary to carefully thin out the end 6mm to 8mm of each the needle in carby and thus achieve the low CHT on full power. (do not think of touching jet) Fuel is cheap when compared to repairing heads. Limbach Tech bull 53 makes mention of max on climb of 180degC (forget what max the manual says - that is stupid value) Also Tech bull 44 (11page edition) is well worth a read. Ian mcPhee 2010/1/27 Michael Grimwood <[email protected]<mailto:[email protected]>> Hi John and Lasse I have owned a Mk1 H36 since 1988 (G-MRG in the UK, now VH-VRG in Australia). It originally came with an un-sprung ________________________________ Yahoo!7: Catch-up on your favourite Channel 7 TV shows easily, legally, and for free at PLUS7. Check it out<http://au.rd.yahoo.com/tv/catchup/tagline/*http://au.tv.yahoo.com/plus7/ ?cmp=mailtag>. ________________________________ Yahoo!7: Catch-up on your favourite Channel 7 TV shows easily, legally, and for free at PLUS7. Check it out<http://au.rd.yahoo.com/tv/catchup/tagline/*http://au.tv.yahoo.com/plus7/ ?cmp=mailtag>. --------------------------------------------------------------------- You are subscribed to the Dimona Owners Group mailing list. To unsubscribe, send email to: [email protected] --------------------------------------------------------------------- You are subscribed to the Dimona Owners Group mailing list. To unsubscribe, send email to: [email protected] No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.432 / Virus Database: 271.1.1/2654 - Release Date: 01/28/10 19:36:00 --------------------------------------------------------------------- You are subscribed to the Dimona Owners Group mailing list. 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