Model Boat Mayhem - Forum

Please login or register.

Login with username, password and session length.
Pages: [1]   Go Down

Author Topic: A frames  (Read 1333 times)

MichaelK

  • Guest
A frames
« on: December 09, 2009, 10:27:11 AM »

My Matilda is a scratsh built 820mm long with 2 x 540 motors
How are the A frames attached to the hull?
 I've thought of a "P" frame, but not enough lateral strength
  I've thought of a slot for the 2 legs, and also thought of bending the  legs  and then bending the ends of the legs and pinning and glueing them.
It's plank on frame with ply planks ,unfortunatly there is'nt a frame where the A frames have to go.
Do I need A frames? There is about 100mm of prop tube hanging out of the hull
THanks
Mick
Logged

Bradley

  • Guest
Re: A frames
« Reply #1 on: December 09, 2009, 10:44:32 AM »

Hi Mick,
Have a look at this website (click on the propellor shafts) - might give you some ideas -
http://www.gsitek-props.co.uk/categories.asp

Derek.
Logged

DickyD

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 9,497
  • www.srcmbc.org.uk
  • Location: Southampton UK
    • SRCMBC
Re: A frames
« Reply #2 on: December 09, 2009, 10:57:19 AM »

You really need A frames for that length. Though P frames will do the job.

Normally slots are cut in the hull for the frames to go through.

They are then fixed on the inside by drilling the frame and passing a short length of brass wire through each leg to stop the frame pulling out.

Alternatively, depending what your frames are made of you can bend them over on the inside.

Seal on the inside with epoxy resin and something like P40 car filler.
Logged
Richard Solent Radio Controlled Model Boat Club http://www.srcmbc.org.uk

MichaelK

  • Guest
Re: A frames
« Reply #3 on: December 10, 2009, 05:19:33 AM »

Thanks Derek & Richard , I'm getting my props from them.
 I guess that I'll just have to pull the rest of my hair out and line up, A frames, through hull slot, holes in 2  frames, and of course the motor, all at the same time, and do it twice at the same time, for 2 drivelines.
Should be easy! :-))
Mick
 
Logged

Shipmate60

  • Global Moderator
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 5,225
  • You bark - I will bite!!!
  • Location: Fareham
Re: A frames
« Reply #4 on: December 10, 2009, 05:44:54 PM »

Mick,
Line up the shafts first and give the "A" frames plenty of clearance.
Tack with superglue, then finally fit with some car body filler from the outside of the hull then epoxy resin from the inside.

Bob
Logged
Officially a GOG.

John W E

  • I see no ships !!
  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 8,511
  • Location: South shields
Re: A frames
« Reply #5 on: December 10, 2009, 06:41:29 PM »

MichaelK hi ya there

If you do a search on this Forum for HMS York type 42 build, you will find it somewhere in Warships - and you will see how I have made a ply-wood jig up.  This holds the 2 prop tubes and shafts in line, whilst I tack the tubes in place & then glue with epoxy.

I normally , like Shipmates60 has suggested, cut slots for where the 'P' frames or 'A' brackets locate in the hull - slide them in place over the shafts and then tack them into position using superglue.

Ensuring that the shafts turn freely.   I then mask off with electrician's tape around the base of the 'A' frame where it goes through the hull ; I next turn the hull over and I make plywood packing pieces which slip over the 'A' frame leg where it comes through the inner of the hull - this is then epoxied to the hull bottom along with the support bracket leg of the 'A' frame.   The packing piece ensures that the stress is spread out evenly on the bottom of the hull.    If this is difficult to follow, just give a shout and I will put a sketch on here for you.

aye
john e
bluebird
Logged

MichaelK

  • Guest
Re: A frames
« Reply #6 on: December 10, 2009, 09:21:37 PM »

Thank you Gents,
I looked at HMS York, and that jig will make life easier! and I can follow the gluing of the frames inside the hull.
Could be my little project for the weekend
Mick
Logged
Pages: [1]   Go Up