The old Grob 109 design I reckon is a lot more complex than a Dimona but doesn’t seem to crack the mustard like the Dimona does But the Grob pitch change is nowhere as robust as the Dimona one. The Grob has a tricky dual cable actuating system where the pitch change is a 4:1 pulley reduction and the feather is 2:1. (I think that’s right). But the Dimona is a simple 2:1. Heave ho system If the dude with the refitted Hoffman prop wants a Dimona pull handle I have one from VH-WVW. Sent from my iPhone
> On 17/03/2021, at 2:28 AM, Mister Sutton <[email protected]> wrote: > > im a thinkin that you may have kind of answered the question rob. it would > seem whether the mechanisim is for a grob, a dimona or the occasional > industrial size egg beater, there is very little difference between the 2400 > and the 2000. its probably just more aircraft (or industrial egg beater) > specific. not sure what could be adapted for taifun. i know there are > some differences between the mk1 and mk2 h36 pitch change mechs and that crow > bars dont float so well but thats about it. > > i may be able to get you some photos this weekend bruce, of my h36 (mk1) and > a g109a that has been in storage for 5 or ten years if they of any help > > cheers > > ric > >> On 16/03/2021 1:07 pm, Rob Thompson wrote: >> I am only thinking H36 Dimonas..... It has now been 20 years since I worked >> on a Grob! >> regards >> Rob >> >> Rob Thompson >> 0429 493 828 >> >> >> >>> On Tue, Mar 16, 2021 at 3:59 PM Ian Williams <[email protected]> wrote: >>> The prob with the Stemme L2400 Rob was that the oil temp valve and spin on >>> filter were in the way of using the original Grob pitch change system >>> So had to be on the other side (same as the Dimona ) >>> >>> Sent from my iPhone >>> >>> On 16/03/2021, at 5:09 PM, Rob Thompson <[email protected]> wrote: >>> >>>> When we installed a L2400 as a replacement for a L2000, it was a direct >>>> swap... just altering the length of the pitch change cable. >>>> >>>> If you want to use a L2000 pitch change mechanism on a L2400.... They are >>>> just very slightly different and you may find that the prop doesn't >>>> feather completely and may windmill a little bit. >>>> regards >>>> Rob >>>> >>>> Rob Thompson >>>> 0429 493 828 >>>> (Please note that my new email address is [email protected]) >>>> >>>> >>>>> On Tue, Mar 16, 2021 at 10:54 AM Michael Stockhill <[email protected]> >>>>> wrote: >>>>> Thanks, Ian. >>>>> >>>>> M >>>>> >>>>>> On Mon, Mar 15, 2021 at 4:43 PM Ian Mc Phee <[email protected]> wrote: >>>>>> Michael >>>>>> >>>>>> Some years ago we fitted a Sauer S2500 to our dimona and were able to >>>>>> use the gear change metalwork. That engine was 15mm longer so rear >>>>>> engine mount was shortened but the master (the bone) was moved to the >>>>>> cockpit of firewall and mounted on standouts and the shaft was >>>>>> shortened. Personally I wod do this simple mod to all h36 as gives more >>>>>> room at rear of slick 4330. >>>>>> >>>>>> We already had the BT Blades (rount tip) and outr STC required that (not >>>>>> the T with point tip) >>>>>> >>>>>> The electric prop sure can use power and as battery gets low it slowly >>>>>> goes coarser. In extreme case it will no longer climb. Thus with the >>>>>> hk36R you must keep an eye on voltage and think manual suggest TURN OFF >>>>>> ELECTRICS to save power. >>>>>> >>>>>> Back to the 2500 Sauer I was never happy with the cruise setting. >>>>>> Recently I got a sliver taken off the adjust nut which brought the two >>>>>> settings closer together. I am extremely happy with the results, not >>>>>> only can I cruise at 90 kts to 95kts (even 100kts). The bonus is IT >>>>>> USES LESS FUEL. The throttle is back 8mm than before. In cruise it is >>>>>> going along at 2800rpm which is close to spot on to max torque. I >>>>>> think previously the engine was labouring going up the hill. The higher >>>>>> revs are fre revs. The engine loves it. >>>>>> >>>>>> Another on props is club has a falke which had L1700 but now fitted a >>>>>> L2000 but have retained the original 75cm pitch (150 dia) which Scheibe >>>>>> approve but most these days have 90cm.pitch. It climbs like a home sick >>>>>> angel at 3000revs >>>>>> >>>>>> I have not answered your question >>>>>> >>>>>> Ian McPhee >>>>>> +61 428847642 >>>>>> Box 657 Byron Bay NSW 2481 Australia >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>>> On Tue, 16 Mar. 2021, 07:44 Michael Stockhill, <[email protected]> wrote: >>>>>>> Ian, >>>>>>> >>>>>>> That would be great if you sent some snaps to Mike Hoffman, and copy me >>>>>>> too! >>>>>>> >>>>>>> [email protected] >>>>>>> >>>>>>> You guys are great. >>>>>>> >>>>>>> M >>>>>>> >>>>>>> >>>>>>>> On Mon, Mar 15, 2021 at 1:23 PM Ian Williams <[email protected]> wrote: >>>>>>>> Gidday Michael, >>>>>>>> I may be of some help there. A few years ago I installed a Limbach >>>>>>>> L2400 from a deceased Stemme S10 >>>>>>>> into an early Grob 109A and used the original Hoffman prop. It was a >>>>>>>> mission as we also applied for a 1 off STC. Which was eventually >>>>>>>> approved by the NZ CAA. >>>>>>>> However at the time I was unaware that the approved prop for that >>>>>>>> combination was an MT. >>>>>>>> So I designed a system based on the Dimona H36 pitch change. >>>>>>>> So it the dude wants some pictures of the system I can send a few >>>>>>>> The Grob has since done about 300 hrs and no >>>>>>>> Problem >>>>>>>> >>>>>>>> Best regards from New Zealand >>>>>>>> Ian Williams >>>>>>>> >>>>>>>> >>>>>>>> Sent from my iPhone >>>>>>>> >>>>>>>> > On 16/03/2021, at 8:58 AM, Michael Stockhill <[email protected]> >>>>>>>> > wrote: >>>>>>>> > >>>>>>>> > I caught up with the Taifun group when researching resurrection of a >>>>>>>> > Taifun here in the states. >>>>>>>> > >>>>>>>> > One Taifun owner makes many 6-8 hour wave flights. He said he >>>>>>>> > removed his MT propeller which requires electric power for >>>>>>>> > unfeathering because his batteries run too low. He installed a >>>>>>>> > Hoffman on his L2400, but he does not have a pitch change mechanism. >>>>>>>> > I expect to ask him if he then flies with the engine windmilling, >>>>>>>> > and has flat pitch for all flight. I don't yet know the model number >>>>>>>> > of his prop. >>>>>>>> > >>>>>>>> > Questions for the group: >>>>>>>> > >>>>>>>> > Are the pitch change lever and components the same on the L2400 as >>>>>>>> > on the L2000? >>>>>>>> > >>>>>>>> > Does anyone have a set of those components for either series engine? >>>>>>>> > >>>>>>>> > I am 1000 miles from my parts books. Are these parts Limbach or >>>>>>>> > Diamond/Hoffman? >>>>>>>> > >>>>>>>> > Thanks for your usual insights. >>>>>>>> > >>>>>>>> > Michael Stockhill >>>>>>>> > Polson, MT >>>>>>>> >>>>>>>> >>>>>>>> --------------------------------------------------------------------- >>>>>>>> You are subscribed to the Dimona Owners Group mailing list. >>>>>>>> This list is archived in public. http://waikeriegliding.com/dog/ >>>>>>>> To unsubscribe, send email to: [email protected] >>>>>>>>
