When you are making up the frames, or moulds as they are sometimes called, it is best to make up the two halves of the frame at once.   This is achieved by nailing the two pieces of timber together, usually 1” by 8” [25mm x 200mm] or similar sized material and of suitable length to cover the section of the frame you are making.   The two pieces are tacked together and the pattern marked out on one side.   Clearly mark the waterline, sheer line and headstock line where they occur, on any one frame section.    After you have joined up, faired and clearly marked the line of the outer edge of the frame you are making; then carefully cut the frame section out on a band saw or other suitable saw.   Make sure you cut the frame piece square off the marked surface otherwise the two sides of the frame will not match.

   Once you have assembled the pieces of the frame to make up one half, which consists of two layers; these should be joined on one side with gussets.   Next remove the nails holding the frame halves together and lay out the frame as you would open an oyster and bingo you have the entire frame.  

   Before you attempt to assemble the complete frame, measure directly from the patterns, the width of each frame at the headstock line; sheer line and waterline and make a check mark on the opposite side of the frame patterns and include the frame number.   Now you have three reference points to make sure the other half of the frame is laid out symmetrically.   Problems can arise if you try to use the offsets when taking the measurements off the patterns as these may not have been corrected at time of lofting.

   Now you can lay out the complete frame by installing the headstock or baseline board,  and gusset the keel together;  add bracing and strengthening members to the frame as shown in the your plans.   Your frame must pass the test of both sides matching the master pattern.   You now have one completed frame ready for installation on the strong back, bedlogs or setting up rails.   After you have marked out all the frames, stem and the backbone and they have been cut out and assembled, your next job is to prepare your strong back or bedlogs. 

SETTING UP THE FRAMES

Usually, the bed-logs or strong back are made from 6” x 2” [150mm x 50mm] or similar sized timber, depending on the size of the vessel.   Your plans should give guidance on the scantlings and assembly method for the setting up base.  The size of the strong back, which is the width and length, will be decided by the shape and size of your hull. The forward end will be narrower to accommodate the shape of the frames whereas the aft end will be wider for the same reason.   As the widest part of the hull is normally around or just aft of the centre, it will be easy to arrange adequate support in this area. Sometimes it is best to build the strong back coffin shaped, to offer the best support to the hull, at all its various widths.  

   The setting up height is quite important.   The hull will be upside down and there must be room for you to have easy access under the sheer and into the interior of the hull.   Your hull must not be so low as to allow the bow, which is usually the lowest point, to touch the floor.  

Once the strong back is completed, it should be checked for level in all directions. The use of chocks and wedges can correct any misalignment.   Make sure any blocking or wedging is done so it will remain permanently in position until the hull is completed.   If you are working on an earth floor you may wish to install concrete pads.   The strong back and the whole mould structure must be capable of supporting the weight of the completed hull, until the laminating and fairing is completed and the hull turned over.  

   Once you are satisfied that the strong back or support rails are level in all planes and securely in position, install a string line down the centre line and mark out the station spacing on the rails on both sides of the strong back.   All station marks should be marked square off the centre.   Nailing 2” x 1” [50mm x 25mm] cleats across the strong back or bed-logs, at each station point, may be the best way to accurately position the frames.   Make sure you consider which side of the station mark your frame is to be positioned.   Make sure the frames are installed square off the centre line and level across the headstock line.   It will be necessary to attach each frame to the strong back.   You may attach the headstock to the upper rail or the bed-log, by through bolting, coach screws or skew nailing.   Access to the strong back or bed-logs may decide your method of attachment.   Remember you will not want the strong back to come loose and be waving about during the turning over process.