Old Hirobo Bell 47

[pchristy]

Well, the one's Dave had were all for the later version, and too short for a Mk1 - so there won't be any test flying tomorrow!

However, the bend is only tiny, so I'm hoping one of my mates who will be at the field tomorrow, will put it in his lathe and tap it straight.

Then I can get another mate (who loves doing this kind of thing!) to knock me up a couple of spares from the other (bent!) sample I have.

What a lovely hobby this is! There's always someone around who can fix/make almost anything!

[lawrencelkl]

Hi Pete,

How is your Bell 47G doing? any test flight yet? the weather cannot be any better since last few days!

I have now got a pair of Vario semi blades which I will bring back to test next month. Getting really excited about that and hope it will improve the lift over my symmetrical pair!

Will report the performance once I get back to UK!

Enjoy flying!

Cheers.

Lawrence

[pchristy]

Yes! Between the weather and work interrupting proceedings, its been a bit of a struggle! As soon as the fine weather arrived, work wanted me in every day! I've worked all week-end (Grr!), extended hours at that (thanks, Eurovision!) and then they rang and wanted me in again today! Needless to say, I declined!

I gave it a maiden hop a couple of weeks ago with the new ignition system in, and couldn't get out out of ground effect! A couple of inches off the deck was all it could manage! I changed the plug a couple of days later, but no improvement! With the Scottish Nationals approaching fast, I re-installed the Hirobo ignition, and suddenly all the power returned! I think its a timing issue, but I've had a few minor mechanical gremlins to sort out as well, and as Scotland is next week-end, I've decided to stick with the Hirobo ignition until I have time to investigate further!

I put the new blades on this morning to replace the woodies I've been using whilst sorting out the bugs, and she flew fine. I've loaded up the engine a lot more. It sounds like its over-pitched, but flies OK and it seems to have cured the misfire, once the engine is warm.

So now its wrapped in cotton-wool and awaiting Thursday morning, when we set off for Aberdeen (at about 0600! Ugh!)

If all goes well in Scotland, I'll have another play with the new ignition when I get back. Despite being set up as recommended, I don't think it had enough advance. I suspect the engine is lower revving than those for which the ignition is designed. But I haven't given up yet!

To be continued......

[electricsceadu]

good luck in the scottish nats pete


and if you wish to over power the old girl retro fit a zenoha g290rc into it
as the one in my vario bell 47g3 is a total power house that just pulls and pulls, i can't wait to see how much better it gets once run-in

[lawrencelkl]

Hi Pete,

Thanks for the updates. Glad that she is back to OK with hirobo original ignition. Hope it serves you well at the Scottish Nat. I will try to load up the new blades as well to lift off mine this time. but first is to repair the tail boom broken bits.

I have made the tube end with dowel and vice as you recommented (at an angle)and it seems working fine. I made a few 'plug in ' ends so that I can get it repaired quicker once back home end of this week.

keep us updated on how it goes in Aberdeen.

Cheers

Regards,
Lawrence

[pchristy]

Thanks for the good wishes, folks! I'll let you know how we get on!

I think its actually a good thing for a scale model to be slightly under-powered. It forces you to fly it in a realistic manner, as the full-size machines have nowhere near the power-to-weight ratio that we enjoy! As long as I have a positive rate of climb, I am happy!

Just hope the weather holds for Scotland........!

[lawrencelkl]

Thanks for the good wishes, folks! I'll let you know how we get on!

!

Hi Pete,

How did it go? any video upload?
I am back from Malaysia yesterday morning. I tried the Vario Semi Blades (order number 420) on my Bell 47G in Malaysia and wow! great improvement on the lift compared to previous symmetrical baldes.
Previously in Malaysia the symmetrical blades struggling to lift, was only managed to 'hop' at almost full throttle.. and with this vario semis, it lift easily at mid throttle so sufficient margin to climb out etc.

in order for fair comparision, i jsut swapped the blades and did not change any single setting and it was absolutely great flyer now.

Also, previously i have broken tail structure and I did repair using the method you suggested, i.e. aluminium tubes with dowel insides. and it worked very well with some epoxy! thanks for the tips Pete.

now I only wish I get to fly it more ofthen. it is like maybe on average twice a year whenever I am back to Malaysia...

anyway, glad that it is flying well now. did noticed some vibration at the tail 'hoop' so next trip back I will try to do something about it.

Cheers.

Regards,
Lawrence

[pchristy]

Well, I won the scale event! Haven't had time to down-convert the video for youtube yet, but will try next week!

The comp wasn't without its problems. During the practice session, the engine backfired whilst starting, resulting in damage to the recoil starter. The nylon pulley that the cord wraps round split in two! I didn't think it was repairable, and was resigned to not flying, but Paul Roberts came up with some brake cleaner (to de-grease the joint) and some new super-glue from MacGregors. Now I've never had any success trying to glue nylon before, but we left it for a couple of hours and it seemed secure. I didn't try and start it again until the contest flight - just in case it broke again - but it held fine, and allowed me to take part in the flying section.

How long it will last is a good question! Dave Nieman has no spares for it - although he has a few recoil starters that have been robbed of this pulley! Obviously it is a weakness! I'm going to be seeing someone from RipMax next week, so I plan to ask there. Failing that, I'll have to try and persuade someone to machine me a replacement.....

Next job is to repair some "hanger rash" that it acquired in Scotland, and try re-fitting the RXcel ignition.

Onward and upwards, as they say!

[pchristy]

Should have added that the Scottish Nats were something of a clean sweep for my club (Watford Wayfarers). Steve Roberts won F3C, F3N and the Auto spot (with Dave Wilshere coming second). Roger Mayo (WW member) came second in F3C, and with me winning scale, it means the only trophy we didn't win was "Best Scottish" pilot - which would have been pushing it a bit!!!

[electricsceadu]

you should have worn a kilt
and spoke with your best scottish accent
for the best scottish pilot

how many scale heli's competed this year?

[pchristy]

Sadly, only 4 - and I entered two! It wasn't the best turnout for any of the classes. Probably something to do with the weather (thought it was fine - if cold - in Aberdeen!) and the financial crisis.

There are loads of pix up on the Scottich heli-nats website: Scottish Model Helicopter Nationals - News

Click on the Photo Gallery tab, then the "General Photos 2012" picture to view the gallery.

And come on guys, lets have some more entrants next year! The Scots are amazingly hospitable!

[lawrencelkl]

Well, I won the scale event! Haven't had time to down-convert the video for youtube yet, but will try next week!

I'm going to be seeing someone from RipMax next week, so I plan to ask there. Failing that, I'll have to try and persuade someone to machine me a replacement.....

Well done Pete, Congratulations!!! I have to say that it sounds not easy nor straighforward at all to finally get her fired up and winning the scale category!

I am still waiting for your youtube video!

by all means, if you managed to persuade someone to machine you one, please make it a pair and I am more than happy to take the other one as contingency spare for my Hirobo Bell 47 G

Cheers!

Lawrence

[Johnny Bravo]

The comp wasn't without its problems. During the practice session, the engine backfired whilst starting, resulting in damage to the recoil starter. The nylon pulley that the cord wraps round split in two! I didn't think it was repairable, and was resigned to not flying, but Paul Roberts came up with some brake cleaner (to de-grease the joint) and some new super-glue from MacGregors. Now I've never had any success trying to glue nylon before, but we left it for a couple of hours and it seemed secure. I didn't try and start it again until the contest


Failing that, I'll have to try and persuade someone to machine me a replacement.....

If you pm me some photos of the offending part, i will look at making a replacement.Have a very nice setup, not much i cannot make. Besides, its a Hirobo..... I have a soft spot for them.......

[pchristy]

If you pm me some photos of the offending part, i will look at making a replacement.Have a very nice setup, not much i cannot make. Besides, its a Hirobo..... I have a soft spot for them.......

Thanks for the offer! I'll bear it in mind if I can't get a replacement! Haven't had chance to down-convert the video from HD yet (it takes ages - even on a fast computer!), and it looks as if I'm going to be busy for most of the week - but it IS on my "to do" list!

[electricsceadu]

[QUOTE=Johnny Bravo;857581 Besides, its a Hirobo..... I have a soft spot for them.......[/QUOTE]


i would never have guessed that one