GP14 Sailing Forums Forum Fitting rowlocks/ oar length

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    • #24352
      Mike_H
      Participant

      Hi all, I have an old GRP (8049) that I am slowly upgrading and hoping to tempt my young daughters into sailing with me. They have some interest in rowing, which might help them feel comfortable in the boat. Any advice on fitting rowlocks and position? I’m thinking of sitting in and getting a feel for what is the right position. Also, what length of oar?  I’m thinking they would need to be quite long. If anyone had anything suitable in the midlands area, that they would consider selling, please do message me.

      Thanks!

      Mike

    • #24353
      Oliver Shaw
      Moderator

      Rowlock/Crutch Socket location:

      It would indeed be a good idea to experiment with a mock-up,  to see what is comfortable.    However the following dimensions have proved to work well for me,  and also for my various crews,  on two successive boats;   so they may well be a good start for you.

       

      Approximate measurements from A Capella

      (Measured, albeit only with tape measure, so a little crude, 12/01/22)

      Distance abaft centreline of thwart 19” or 48 cm

      Distance forward of at face of transom 53.5” or 136 cm

      As far outboard as possible; those on A Capella are not really far enough outboard.
      This is in order to avoid oars chafing on rubbing strake on the pull stroke.
      If using flush rowlock sockets it may also be necessary to raise the rowlocks slightly by means of a collar.

      Spindle diameter 12 mm (less than ½ inch)

       

      Length of oars.   Absolutely the longest that you can stow in the cockpit,  and even then you will feel that you would have liked them slightly longer.   I cannot remember whether A Capella‘s oars are nominally 7′ or nominally 8’,  but I will try to remember to measure up when I am at the boat in the next day or two.    However do be aware that the lengths of manufactured oars do not appear to be exact round numbers whether measured in Imperial or metric units.   If you can try a selection for size,  so much the better.    Or you could try a length of 2″ x 2″ timber to see what you can stow.

       

      Stowage of oars.    On A Capella (a Series 2 boat) I have them on the cockpit sole,  as far outboard as possible,  retained outboard by a length of shockcord.    That requires that the loom end be passed under the thwart (from aft) when stowing it,  and the maximum length is then determined by what will clear the stern deck as you work the oar forward under the thwart.

      On Tantrum (a series 1 boat,  with the original twin-slat side benches) back in the late sixties and early seventies I had the oars mounted above the outboard slat of the side benches,  retained in place by plastic “Terry” clips.   There,  choosing the length is less critical;   the oars merely need to fit into the cockpit.

      Hope this helps,

       

       

       

      Oliver

      • This reply was modified 1 year, 10 months ago by Oliver Shaw. Reason: Completion of reply after "blind" copy and past of data, which for some obscure technical reason was not visible until submitted
    • #24356
      Windychippy
      Participant

      Mike,  I have just measured the rowlock socket position on my newish wooden Dinghy “Neema” The centre of socket is 1370mm from rear of Transom measured along the side deck. The deck is approx 125mm wide at this point and centre of socket is 40mm from outer edge. When measuring under deck the socket is approx 30mm from inside the hull. The socket is mounted through an under deck support block which sits tight up against the rear side of the 3.5 station former this sits at 1395mm, so the socket is approx 25mm to the rear of that former.  Having read a few rowing blogs on line with them giving various formulas and ideal measurements I soon realise that the only measurement that I could glean was the one for how far aft from the seat to place the sockets. The Ideals seemed to place the socket smack on top of the 3.5 former. So to place it just fore or just aft was the decision to be made. I think I read somewhere on this forum that Oliver Shaw place his sockets just aft of 3.5 so I did like wise. Mind you if you decided to place them just in front of 3.5 I think that would work to, just sit with bum overhanging thwart a bit.

      I purchased 8ft oars which arrived being only 7ft-10 1/2in and these fit easily under the thwart from the rear. There seems to be room for slightly longer oars may be 4 or 5 ins longer ( they say the longer the better ) If you are going to just row with your family (No mast) then even longer will do but you will need to stow these on the side decks .

      All the best   Windy

    • #24357
      Mike_H
      Participant

      Thanks Oliver thats a great start – good idea to get some 2×2 and check stowage. I’ll take those notes down and see what that looks like. I see one oar seller recommending oar length as 1.5x beam so will add that to the mix.

    • #24358
      Oliver Shaw
      Moderator

      Oar length;   those on A Capella are 82½”,  or 2085 mm,  long.    So they are probably a nominal 7′ (84″).   I did warn you not to expect round numbers!

      They fit nicely between the forward buoyancy tank bulkhead and the aftmost side bench support.

      Hope this is helpful,

       

      Oliver

    • #24359
      Simon Heath
      Participant

      I’ve just got back from a holiday in Wareham, Poole harbour and have some very imporatant advice! Don’t buy the shiny chromed brass rowlocks as they have a fatal flaw. They break! Buy the galvanized ones. I have a pair of Lahna Seagrade 2.7m oars which seem about perfect length, just fitting in my old (I believe) series 1 with wooden benches and full length buoyancy tanks I store them on the floor as they take too much of the seat. They can be left in the row locks on the deck just in board of the rear horse.

      The oars  didn’t sit quite comfortably in the row locks as the internal diameter was a bit low. I tried them out at my sailing club before venturing out to sea and they needed a bit of a push and twist due to the rubber collars to get them so they didn’t get in each others way.

      I sailed down the first part of the Wareham channel from our slip at Redcliffe campsite, about the first 1km, as we turned up wind, just after Ridge Wharf yacht centre. I decided to drop the sail and row as it was too narrow to tack. Pushed one of the oars in place then the other and it went ping and jumped out the row lock base. Thought that’s odd – I’ve got cotter pins to keep the row lock in place. Then realised with a heart sinking feeling… it was the rowlock had snapped at it’s narrowst point. Thankfully I’d read a lot of the advice on here, so had an anchor with 2m of chain and 30ft of rope, which was dropped after I managed some SUP Style rowing to the bank standing up with 1 oar, Then we wedged the boat in place at the rear by using the oar. But I’d now lost my means of propulsion. Thankfully after a 30 minute wait we managed to flag a passing tourist trip boat for a tow back up stream. Had no one come, I’d got a phone and floating handheld VHF to call the marina.

      Having just done my Powerboar 2 last year meant I knew how to hitch on a tow unlike the boat owner who wanted to tie us on. It’s much safer to have a loose wrap around a cleat and hand hold it so when the tow slows, you can pull in the slack and not risk getting the prop wrapped. Same at the end of boat being towed. Either one can let go if something goes wrong.  Also keep the tiller on, but raised so it’s just in the water so you can help navigate tighter turns, and as we did…. get a slingshot back onto the slipway where I was able to land us perfectly.

      The new 10mm galvanised locks I bought from a chandlers in Poole didn’t quite fit, thankfully my parents have retired down there so dad came out with an 11mm metal drill to widen the base plate and now they fit perfect.

      One thing you may want to practice with daughters is rowing with the tiller in place. My 8 year old was zig zagging us all over the place on the first trip even though she can sail an oppy. However on 2nd trip my mum came along So with the new rowlocks we managed to get out the River Frome, had a beat up wind in the main channel back and forth. I didn’t realise outside the channel it was only about 2ft deep at hight tide, not enough for a centreboard!,  so would have rowed a bit further had I known, despite having just bought the Poole Harbour map. I had done some training with Rockley last year based up the top end of the harbour, and despite it drying at low tide, at high tide a dinghy can clear the shallow water.  We even managed to beat an Elan 22i into the moorings near Hamworthy, despite me having to have a tack as I was running out of sea on a close haul.

      We sailed all the way across Poole Harbour including the main ship channel and had to avoid larger traffic (which was my main mission… to practice my COLREGS), over to Baiter Park, dropped mum and daughter then back, a bit faster this time with the boat heeled, to a secret slip so we didn’t have to pay £14 at Baiter Park.

      Am currently looking at electric outboards with hydro-generation, as I’d prefer to be getting down the river much quicker. According to Google maps it’s 3km. And we’re likely to camp there again.  Plus having 2x 2.7m oars  means you are quite wide and have to keep out of everyone’s way, Long term plans are for a 32+ foot yacht with tender, so its helping spread the cost of the upgrade 😉 The electric outboards allow you to store the battery inboard to help boat balance and most important don’t make a racket or stink when running.

    • #24364
      Mike_H
      Participant

      Thanks also Windy and Simon for the advice. Sounds like you had fun in Dorset, Simon.

    • #27047
      Steve
      Participant

      Hi all 🙂

      I appreciate this thread is almost 2 years old, but it seemed a good place to pose my question…

      I have a series 2 (converted from series 1) which I generally use for cruising, which doesn’t have rowlocks fitted.
      Are there any “how to” guides available on fitting rowlocks?  Or is this a job best left to the professionals?  (I’d be nervous cutting holes!!)
      If the latter, can anyone recommend a good dinghy builder in the north west that could make these modifications?

      Thanks all 🙂

       

    • #27056
      Oliver Shaw
      Moderator

      Noting that this is a wooden boat (Series 1,  with the series 1 to 2 conversion done),  that you say you are nervous of cutting holes,  and that you want a good dinghy builder in the north-west,  I would recommend Tim Harper,  who is based in Southport.   He has in his time built some beautiful,  and somewhat bespoke,  GP14s,  including my own A Capella.    Last time we met,  at a Past Commodores’ Dinner earlier in the year,  he gave me the impression that he is now semi-retired,  and said that he no longer builds,  but still does repairs.

      It would be worth determining first where you want the sockets to go;    there is a lot of material pertinent to this earlier in this very string.

      Then decide on what rowlocks you want.    Metal is vastly stronger and more rigid than plastic,   so I personally would never have any confidence in plastic ones.   Galvanised are el cheapo,  and very strong,  but a bit “agricultural”;   you may feel (as I myself do) that to fit them to a beautiful wooden GP14 would deface the boat.

      The strength of Chrome-plated rowlocks depends heavily on the quality of the substrate,  which is likely to be either brass or die-cast zinc alloy.    I have heard mixed reports,  with some owners reporting fractures,  and others having had no problem.   Indeed there is one adverse report almost immediately preceding this reply in the same string.   However it is difficult to compare like with like,  as I have no information on particular brands;   and even for the adverse reports that I have heard in most cases I cannot recall what the substrates were.

      For my money the choice is either stainless steel or bronze (gunmetal).   Bronze are probably the easier of the two to obtain,  and are normally available from Classic Marine,  or other specialist classic chandlers (such as Marinestore.co.uk,  or Davey & Co.)   Stainless steel may require quite a lot of online searching,  but if you can find stainless ones (that you like) they will be amply strong and they will also be a good cosmetic match to the rest of your stainless fittings on the boat.

      It would be worth discussing this with Tim before you buy;   he may possibly have sources of supply,  or he may prefer you to source them and he will then simply fit them for you.

      The neatest type of installation is to have the deck plates (sockets) recessed into the deck so that the surface is flush;  and that also gives the most comfortable seating if you happen to sit on top of one of the sockets.   However if you opt for that you may find that you need to put a short collar on the stem of the rowlocks in order to lift them a little,  so that the oar does not scuff your varnished rubbing strake on the pull stroke.   I made my collars by buying a short length of stainless steel tubing of suitable diameter (again an internet search will bring up suppliers),  and then cutting it to length.    The length is not critical;   half an inch,  or 15 mm would seem a good length to try.

      Hope this helps,

       

      Oliver

    • #27081
      Steve
      Participant

      Thanks Oliver 🙂

      I’ve dropped an e-mail to Tim.

      In the meantime, have you any suggestions on how to reinforce under the deck to take the forces of the oars?
      e.g. type of wood to use, size of the block, how to fit it in place, etc.
      (Just in case I’m brave enough to take the job on myself 🙂  )

      Thanks

      Steve

    • #27082
      Oliver Shaw
      Moderator

      If you ask Tim to fit the plates he will of course do the reinforcing.

      It is not a job that I have ever done myself,  but it is one that I would have been perfectly happy to do.    (Tim fitted the socket plates on A Capella,  since this was part of the build).    Sitting at home in my armchair(!) I would expect to do the following:

      • Measure up and mark the centres of the holes.    Double check these measurements;    the old adage is “Measure twice,  have a cup of tea,  then measure again;  then cut once”.
      • Offer up a piece of mahogany under the deck,   I suggest 3/4 inch to 1 inch thick,  very substantially longer and wider than the socket plate,  but precise dimensions not critical;   bond this in place with epoxy.    If underside of deck is bare,  or if it is coated with epoxy,  the new bond will be strong.    If it is merely varnished,  the bond will be the (uncertain) strength of the varnish,   so err on the large side with your choice of dimensions for the reinforcement.     One way to hold the reinforcement in place while the epoxy cures would be to drive a single screw into it from above,  screwing exactly through the marked centre;    once the epoxy has set you can remove the screw,  and when you then drill out the hole all trace of that screw will have been removed.   Preferably remove the screw before the epoxy has cured fully hard;   but if you misjudge and then find difficulty in getting the screw out a soldering iron applied to the head of the screw should soften the epoxy enough to enable removal.
      • The socket plates may have a very short downward protuberance around the hole;   to call it a tube would be too grand a term,  perhaps between 1/8 and 1/4 inch (3 to 6 mm) deep.    If so,  using a self-centring wood bit,  drill out to that diameter and depth  –  adding the thickness of the plate to the depth,  to enable the socket plate to eventually sit flush,  recessed into the deck.    If no such protuberance,  reverse the order of some of the following steps;   drill for the shank first,  using a self-centring drill,  then match the plate to the drilled hole,  using the drill bit as a mandrel for getting the plate in exactly the correct position.
      • Insert the plate into that hole (it will of course still be sitting proud of the deck at this stage),   line it up accurately fore-and-aft,  then use a Stanley knife (craft knife) to mark around the outside.    This will probably be a rectangular shape;   if you happen to have chosen socket plates of elliptical shape this really is making a lot of extra skilled work for yourself!   Take great care to cut exactly along the line of the plate,  and not to mark the varnish outside the plate.   You can afford to cut into the deck to fractionally more than the thickness of the metal plate.   Note that at this stage you have still not cut the hole for the shank of the rowlock;   that is left for much later.
      • Using a freshly-sharpened wood chisel,   remove  the necessary depth of plywood from inside the marked region,  taking particular care not to damage the deck outside that marked region.    It is vitally important that the chisel is really sharp.   Initially settle for making the hole very slightly too small;   it is easy to open it out further,  but impossible to do an invisible repair if you cut too much!    Aim to achieve a level bottom to your hole,  which will perhaps be about 1 mm deep.
      • Using the chisel and the Stanley knife as required,  open out the hole until the plate sits neatly inside the hole,  and flush with the deck.
      • Once you are satisfied with the fitting of the plate,  insert the securing screws.
      • The shank diameter will typically be either 12 or 13 mm or 1/2-inch (which falls between the two metric sizes).   Provided you have access to the correct size of drill bit (which may be a problem if it is 1/2 inch and you have only metric sizes),  you can drill through the socket plate,  and in that case the bit does not need to be self-centring;   either a wood bit or a metal bit will do equally well,  as the plate will keep it centred.
      • So,  with the plate fitted,  and screwed down,   drill through the hole in the plate for the shank of the rowlock,  provided you have the correct drill bit size.
      • However,  if you find yourself having to drill fractionally larger than the hole in the plate,   e.g. 13 mm for a 1/2 inch plate (just 0.3 mm over-size) you will need to take the plate off again,  and then you must use a self-centring wood bit;   a bit designed for drilling metal will be too prone to wander off the true line.
      • Now check the rowlock in the hole,  to test for a good fit.
      • Finally,  with everything fitted,  and working,  remove the plate again.   Varnish the bare wood.    Then refit the plate,  bedding it down onto your choice of sealant.

      Job done!

      It actually sounds more than it is;    if you are reasonably familiar with quality woodworking the job is not particularly difficult.    But accuracy at all stages is the name of the game,  and if you are nervous of your abilities then it is a job perhaps better left to a professional.

      If you happen to read these posts by email rather than on the website,  please be aware that this one has had several edits,   so do look up the latest version on the website.

       

      Oliver

      • This reply was modified 1 month ago by Oliver Shaw. Reason: Notification of edits
      • #27083
        Oliver Shaw
        Moderator

        The differences in likely shank diameters,  i.e. 12 or 13 mm,  or 1/2 inch (= 12.7 mm) can be significant.

        Although in deference to age (81) I have reluctantly retired from GP14s,  and have very happily passed A Capella over to my godson as an advance on his future inheritance,  I have recently refitted her for him.    After revarnishing the decks and replacing the fittings the starboard rowlock was fine,  but the port one was very stiff.    The obvious solution,  in default of a reamer,  was to re-drill the hole for the shank.

        I tried a 12 mm (metal) drill,  but it went in far too easily,  and achieved nothing.    I then tried a 13 mm drill,  but that would not pass through the hole in the socket plate.   However I am of an age to still have some pre-metric tools,  so I then tried a 1/2-inch drill,  and it did the job to perfection.    A Capella‘s rowlocks,  bought new in 2006,  very much in the metric era,  clearly have 1/2-inch (i.e. non/metric Imperial size) shanks.    Of course,  I could have saved myself a couple of trials had I bothered to get out the micrometer,  or the verniers,  and actually measure the shank  …   …

         

        Oliver

    • #27088
      Steve
      Participant

      Thanks so much for the comprehensive replies Oliver.

      Much appreciated 🙂

    • #27089
      Oliver Shaw
      Moderator

      Steve,

      In an idle moment I looked at your profile,  and spotted the name of the boat.    That name rang a bell;   and coupled with a sail number around 9000,  and the Series 1 to 2 conversion  –  which is quite rare,  and based in the northwest,  I think I know the boat.    Did you buy her from Peter Johnson,  a member of Liverpool Sailing Club?

      That is my home club,  and when Peter was considering buying her I vetted the boat for him!

      Peter had joined the club a short while earlier,  declaring that he wanted to try out a number of different boats until he had decided which class to buy.   I took him out just once in A Capella,  and he was so delighted with her that he immediately declared that his search was ended;   his choice was a GP14.   I didn’t attempt to persuade him to try others,  because I am an enthusiast for the GP14 myself.

      Regards,

       

      Oliver

    • #27090
      Steve
      Participant

      Oliver, I did indeed 🙂

      Since acquiring her I’ve added a reefing furler to the genoa, and more recently reefing lines to the mainsail following your excellent guide.
      I’ve also sanded her deck back to the bare wood, expoxied and re-varnished.  Slowly fitting her out to be a cruiser, rather than a racer.  I can’t tell you how useful and informative your guides have been in helping me with this.  I’ve even had a couple of them printed and bound for easy reference.

      Haven’t sailed her quite as much as I’d hoped, but have been on Bala, and Barton Broad in Norfolk just a couple of weeks ago, so building my confidence up.  Hoping to join a DCA event when the stars align with my other weekend commitments.

      Best regards.

    • #27091
      Oliver Shaw
      Moderator

      Excellent!

       

      Oliver

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