34" Vosper RAF Crash Rescue Tender - Aerokits model

Started by Back in the Groove

5 updates 56 likes 31 comments

34" Vosper RAF Crash Rescue Tender - Aerokits model

It must have been in the early '70's when my father and brothers built this model. It had a car blower motor, a home made server to steer (see picture), and my eldest brother built the RC system. We had fun on many boating lakes on holidays in North Wales, and I've decided to refurbish her, and get her on the water again. She was named "Endeavour", as my mother said it took a lot of endeavour to build her! I think I'm going to fit the missing chine and gunwale stringers and repaint her as a Fireboat - of some sorts!
I'd like to go modern with the RC, motor (brushless?) and metal geared servo.
Any advice - particularly on motor sizing would be appreciated. I saw a similar Fireboat on the water at Southport Model Boat Club open day recently, with an 850 motor, which seemed to sail very nicely
Liked by DaveWhittaker and Fred and
25 comments
  1. Graham93
    Vice Admiral
    Re: There were actually ten versions of the Fire Float (seemingly often erroneously called a 'Crash Tender')

    Rightly or wrongly, referring to these as 'Crash Tenders' probably has something to do with this!

    Graham93
    Liked by DaveWhittaker and hermank and
  2. Back in the GrooveSilver
    Petty Officer 1st Class
    Graham93,
    That plan looks exactly like the one I have - only mine is much more yellow! I have 2 other documents - the Building Instructions and "Constructional Details"
    Liked by hermank and BOATSHED and

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Float Test!

So having stripped out all the old equipment - see image of home made rudder servo! - I decided to check for leaks. I used some soup cans for ballast, and after around 45 mins found some water coming up the old 3/16" x 9" prop shaft.
Having asked advice on the forum, I need a new 5mm prop shaft, but will wait until I have the motor, before ordering one. I may need a different length, and now I know I'm opening the hull, I may as well fit a new metric rudder and tube too 🤔
Liked by AlessandroSPQR and SouthportPat and
1 comment
  1. Martin555
    Fleet Admiral
    Hi,
    I like that old servo system, using that system slightly modified you could control all sorts of things.

    Martin555.
    Liked by hermank and BOATSHED and

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Restarting the Refurbishment

After a very long pause 🙄, I have resumed work on the Crash Rescue Tender.

I found and tested the new electronics I'd bought:
Controller: M-Troniks G2 Hydra 50
Motor: M-Tronics Brushless 1900KV 600can (came with Controller)
Antenna: Futaba R3106GF
Rudder Servo: Futaba S3004
Batteries: 2 x VP Racing Battery Ni-Mh 10x2600mAh 12V
Transmitter: Futaba T6L Sport

and found the new hardware:
Prop-Shaft: 9” x 5mm dia. (8mm dia tube) with bearing
Rudder: Brass 5mm shaft

Having stripped the paint from the boat, and removed the old propellor and rudder tubes, I set about fitting the new propellor and rudder tubes.
I made a new motor support to ensure alignment with the propellor tube.
I had to enlarge the prop tube hole to 8.5mm to ensure the resin would flow all round the tube for the best seal
Having never used this type of resin, I went for Z-POXY 30min 2-pack, sealing up the outlet of the rudder tube with blu-tak (with space for waste that I would file off once set) and made a small frame from thick card to contain the resin in the hull I drilled a hole to ensure resin got all the way into the prop-tube hole. I poured the resin with the motor, prop-tube and shaft, and outer support all in place to get good alignment, and twisted the prop tube post-pour, to ensure the resin flowed all round for a good seal
I would use a shorter set-time resin in future!

Next, I set about fitting the missing gunwale rubbing and chine strakes. Over 50 years ago, Dad had obviously decided he’d gone far enough and hadn't fitted any.

I steamed the Obechi Gunwale strakes using a plastic tube and wallpaper steamer, then clamped them to a frame mould I’d cut to shape them, which made them easier to glue and pin. I used J Perkins Aliphatic Resin, and the tiny Amati pins and “nailer” – which proved particularly challenging on the beech chine strakes

Overall very pleased with how this is going together. Now to find some paint!
Liked by SouthportPat and DaveWhittaker and
3 comments

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Painting and Fitting-out

I used Johnstones Trade Wood Primer and Grey Undercoat for the base layers, sanding between each coat to try to get a smooth finish. The hull is painted "Victory Red" and "Black", and the waterline painted white with Craftmaster Signwriting Enamel
I made a frame to sit the boat on, using my laser level to project a level line on the boat and after an attempt to paint to this line, changed to sticking a masking tape layer along the line to get a decent line. It was really difficult to paint a line over the chines!
I used Craftmaster Signwriting enamel for the Upper structure - in Silver Grey, Charcoal and Raw Sienna - unconventional it maybe, but at this point I'm not planning to add any fittings to the boat, other than Port & Starboard lights, but am very tempted to paint FIRE and add the RAF Roundels - maybe after I've done running trials!
I've still to fit the rudder mechanism, but filled the prop shaft and rudder post with grease, and tested the RC, and it all works, so 🤞 for a water test in the bath soon!
Do I add polycarbonate windows - or do I need airflow through the boat?
Liked by BOATSHED and peterd and
2 comments
  1. PeteJevBronze
    Petty Officer 2nd Class
    Hi Back in the Groove, are you aware that SLEC models do a decal set for the FIRE wording RAF roundels etc and also an acrylic precision cut window set. I am at similar stage of construction with mine also an original Keil Kraft / Aerokits 34" version. I tested my watertightness on a large puddle that appeared at the bottom of my lawn after a rainstorm!! Must get on and finish it this year.
    Liked by hermank and SouthportPat and
  2. Back in the GrooveSilver
    Petty Officer 1st Class
    PeteJev,
    Thanks for the suggestion re SLEC. I actually had them make me a set of windows and frames for the version of the boat that I have, but I think my drawings were "not the best", so am still trying to decide what to do - and consider if I need to leave the windows out to keep the motor cool
    Regarding the FIRE and roundel decals, I will paint them if I decide to add them.

    Since my last post I have done a successful bath float test, with no leaks, and need some small weights for ballast to the waterline!

    Your boat is looking great, and I like the stand you have for it!

    Cheers!
    Liked by hermank and SouthportPat and

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We are sailing!

I finally got the boat on the Water at Jubilee Pond - the home of Southport Model Boat club
We took some video, which I have uploaded to You-Tube, as I don't know the max file size I can put on this site

I spent around an hour "messing about", and I'm very pleased with how she ran, and look forward to the next time

Thanks to everyone who made comments on my blog, and for the encouragement provided from the site
Liked by hermank and RNinMunich and

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