Model Boat Mayhem

Please login or register.

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

Author Topic: Masking the Waterline  (Read 12189 times)

Aidi

  • Guest
Masking the Waterline
« on: January 19, 2010, 09:40:18 pm »

Yep, its me again!

Having spent a good hour or so ploughing through the various threads on marking the waterline, i am for the first time with my build at breaking point!  Up till now with a bit of advice i have managed to progress with satisfying results. But....  for the life of me i can not get a good line around the hull or apply the masking tape so it looks right. 

I have secured the boat so its perfectly upright along the keel, and then proceeded with a block and pencil attached to mark a line.  The lines meet perfectly at the bow and stern, but where as one side the line when masked with tape looks nice and parallell, the other side takes on a cresent shape towards the deck of the boat.   In looks horrible.

Am i doing something wrong here?   I dont want to go any further as the pencil lines are making the hull look awful.

I thought this bit might be easy, but how wrong was I!    HELP!

Rgds
Aidi
Logged

Tom@Crewe

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 237
  • Location: Crewe, Cheshire
Re: Masking the Waterline
« Reply #1 on: January 19, 2010, 09:48:21 pm »

I do it the same but with the hull inverted
Logged

dougal99

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,326
  • Huntingdon, Cambs, England
  • Location: Huntingdon, England
Re: Masking the Waterline
« Reply #2 on: January 19, 2010, 10:03:11 pm »

Maybe stupid comments, but are you sure that:

1 its not an optical trick?

2. the bench you are working on is flat all over?

3. the pencil is not moving on the block? I have a commercial liner but I still have problems at times if the pencil is too long from the anchor point.

4. the hull does not have a dimple or some such?

Just some thoughts
Logged
Don't Assume Check

Aidi

  • Guest
Re: Masking the Waterline
« Reply #3 on: January 19, 2010, 10:35:21 pm »

Looking at things closely, it would apper that hull is not perfectly symetrical, which is what is causing the line to look horrible.     To say i am pretty peeved after all the work i have done is a bit of an understatement.   
Logged

Bunkerbarge

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 2,510
  • Location: Halifax, UK
Re: Masking the Waterline
« Reply #4 on: January 20, 2010, 12:07:39 am »

You follow exactly the same process as I do and if your lines meet at either end it looks like the pencil and block is stable.

Unfortunately, as you said, it looks like your hull is not perfectly symetrical so I would start with your pencil line as a guide but then 'adjust' when you lay the masking tape.  This may well take quite a few attempts and look a bit strange but you have to get away from the perfect location and try to head towards what "looks right".

You may well be surprised that when you have a line that looks right you won't notice anything else.  It's certainly worth a try as correcting the shape of the hull at this stage is going to be more of a challenge unless you want to start making profiles from the good side to use to smooth over filler on the bad side.
Logged
"Dirty British coaster with a salt-caked smoke stack, Butting through the Channel in the mad March days"

derekwarner

  • Full Mayhemer
  • *****
  • Online Online
  • Posts: 9,463
  • Location: Wollongong Australia
Re: Masking the Waterline
« Reply #5 on: January 20, 2010, 12:36:32 am »

Aidi....before you go TROPPO %%....put some warm water in the bath...add a few tea spoons of talcum powder & stir gently..........the plan is to obtain a fine layer of talcum powder evenly dispersed on the surface of the water

Carefully lower the pre ballasted vessel squarely into water ...let her sit for a few minutes ....... O0 then carefully lift her out & check the water line

Another variation on this theme is partially fill the bath with cold water..... {-) then add 1/2 a cup of thinned black oil based paint.......O0 then carefully lift her out & check the water line

Just don't tell your spouse first  >>:-( <*< :P :D O0 {:-{ :-X :P 8) .....Derek

Logged
Derek Warner

Honorary Secretary [Retired]
Illawarra Live Steamers Co-op
Australia
www.ils.org.au

andygh

  • Guest
Re: Masking the Waterline
« Reply #6 on: January 20, 2010, 07:58:53 am »

Good tip, I like it  :-))
Logged

AlanP

  • Guest
Re: Masking the Waterline
« Reply #7 on: January 20, 2010, 09:22:42 am »

you are brave Derek. I wouldnt like to be responsible for all the beatings caused by people using half a cup of oil based paint in the bath,   {:-{

Alan
Logged

Aidi

  • Guest
Re: Masking the Waterline
« Reply #8 on: January 20, 2010, 10:48:30 am »

Thanks again for all your replies chaps, it is very much appreciated.

I think i am going to have to give the bath option a miss due to two reasons...  I live in communual accomodation, so i dont think it would go down too well with my collegues!! and second the boat has been built as a static model not for water... and knowing my luck it would just sink anyway!!


After a great deal of trial and error, and who knows how many yards of masking tape, i think i have managed to get a line around the hull which from a yard or so away to the eye looks ok.    With a tape measure the distance to the water line from the deck is different on each side, however only by a few mm, so unless looking in detail close up its not that visible.   It was quite late by the time i finished last night, so ill come back to it later today and double check it.

It would appear that something went astray whilst building the hull, thus making it ever so slightly out of symetry. 

Thanks for all your comments

Best Rgds
Aidi
Logged

Wasyl

  • Guest
Re: Masking the Waterline
« Reply #9 on: January 20, 2010, 10:55:23 am »

When i was a youngster,..eons ago,my mum was forever on at me,for leaving a Tide mark on the bath,so if a tide mark can be left after having a bath,then your talc/oil water will be bang on,..just make sure you,ve got a bottle of Cif for cleaning afterwards, {-)

Wullie
Logged

Rex Hunt

  • Guest
Re: Masking the Waterline
« Reply #10 on: January 20, 2010, 01:31:15 pm »

laser spirit level from B&Who?

Rex
Logged

Aidi

  • Guest
Re: Masking the Waterline
« Reply #11 on: January 20, 2010, 04:13:46 pm »

laser spirit level from B&Who?

Rex

never thought of that...  Just checked my local homebase, so i think ill pop down and get one. 

Thanks for the idea

Rgds
Aidi
Logged

dougal99

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 3,326
  • Huntingdon, Cambs, England
  • Location: Huntingdon, England
Re: Masking the Waterline
« Reply #12 on: January 20, 2010, 05:31:13 pm »

Interested to hear how you get on. In theory you should get the same result that the pencil gave ie a horizontal line that doesn't look right viewed from certain angles. Let us know your findings please.
Logged
Don't Assume Check

des321

  • Guest
Re: Masking the Waterline
« Reply #13 on: February 05, 2010, 11:37:38 pm »

Having the same problem for marking a tricky yacht hull I went to Homebase today and for £11.99 bought a laser level that produces a horizontal beam. It made the job really straightforward. I will always use this method in future. Unless someone has an even better idea.
Logged

pugwash

  • Guest
Re: Masking the Waterline
« Reply #14 on: February 06, 2010, 12:06:57 am »

If you get a laser level it should do a brilliant job - just finishing tiling two bathrooms , kitchen and utility room
- never  more than 1mm out of line after going right round the bathroom - just make sure it is well anchored
down and your workbench does not move when you go near it to mark on the pencil line
I can now get back to my model
Pugwash
Logged

John R Haynes

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 265
Re: Masking the Waterline
« Reply #15 on: February 06, 2010, 11:02:25 am »

On larger hulls especially ,if you put on the masking tape straight and level you will get a hogging effect . Mark the W /L straight as normal and then  when applying  the tape [ Tamyia ] allow the tape to slightly fall in the middle . This will fool the eye into thinking its straight and level .
I  fix the tape to the bow and with my eye on the pencil waterline , run the tape to the stern and a natural droop below the w/l appears . You may need to do this several times until it looks right from the side at a distance but avoids a sagging look .
The tape needs to rise above the W/L at the bow also to get a correct look. and was done on real ships. 
Logged

justboatonic

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 1,516
  • Location: Thornton Cleveleys
Re: Masking the Waterline
« Reply #16 on: February 14, 2010, 09:58:38 pm »

I normally use my eyes tbh. I drew the WL on Drumbeat this way although it is a straight sided hull. Was thinking it may be more difficult on the MSW Envoy Im now build so will consider a laser level.

Guess it will come in useful when swmbo wants me to put up more shelves!
Logged

tomo55

  • Guest
Re: Masking the Waterline
« Reply #17 on: March 10, 2010, 12:17:26 pm »

Like the talc idea Derek not sure if my better half would agree to the oil based paint though.I think id end up sleeping in the shed (A bit cold at the moment)
Chris
Logged

Bradley

  • Guest
Re: Masking the Waterline
« Reply #18 on: March 10, 2010, 04:43:32 pm »

My method of marking the waterline is to mount the hull, inverted, on the kitchen table which is nice and smooth.  Mark the waterline at the bow and stern, set the hull up on wooden blocks and adjust them until the bow and stern markings are the same height.  Then, using the piece of equipment shown below which, I believe, is called an engineer's scriber, with a pencil securely taped on, set the pencil to to the required height and slide the scriber along the table marking the waterline as you go and 'hey presto' one waterline accurately marked out. :-))

Derek.
Logged

derekwarner

  • Full Mayhemer
  • *****
  • Online Online
  • Posts: 9,463
  • Location: Wollongong Australia
Re: Masking the Waterline
« Reply #19 on: March 11, 2010, 06:00:08 am »

mmmm......... this is clearly a bit cleaner than my concept of black paint floating on water in the bath  O0 {-) %% :embarrassed: :D :} :o .....Derek [from the other side of the world]
Logged
Derek Warner

Honorary Secretary [Retired]
Illawarra Live Steamers Co-op
Australia
www.ils.org.au

tomo55

  • Guest
Re: Masking the Waterline
« Reply #20 on: March 13, 2010, 01:21:01 pm »

Just a bit cleaner Derek
And your better half wont banish you from the house.must be a result.
chris
Logged
Pages: [1]   Go Up
 

Page created in 0.103 seconds with 22 queries.