Advice on simple building practice please


So I have made an horrendous jif65 (contains the new main ingredient - body filler) and moved onto planking and glassing a little racingsparrow 350 for practice. It’s come on in leaps and bounds thanks to all the build logs I’ve seen here etc, but 3 BASIC questions I have are:

  1. I extended the bulkheads to fit onto a jig (so the deckline sits about an inch above the board, all the same amount of wood added) and planked it. How on earth do you elegantly cut them off? I manged but not in a pretty manner at all. which leads to question #2

  2. How on earth do you get a nice straight deckline to fit the deck to? Mine is sanded by eye but there must be a better way. Do you use a really long sanding block that reaches both sides or what?

  3. At what point do I make the countersunk sections in the bulkheads for the spruce supports etc, and how are you all doing it so neatly? I tried a blade last night and although functional it really is ghastly. I know you’ll never see it but I’m having so much fun making these things that I’m getting a bit silly with details :slight_smile:

Thanks in advance


Andrew -

will attempt to answer what I can - and leave remainder to others.

  1. I built my very first JIF on a piece of glass with deck/bulkhead drawing underneath. I used a small block of foam and glued my bulkheads to it. Then use a few drops of CA glue to fasten foam block to glass. After locating the bulheads and fastening, I took a long piece of “dental floss” (a waxed string for cleaning between teeth) and looped it around the foam block, letting each separate piece of thread stick out well beyond the deckline. Once I had panelled the hull (4 pieces balsa with hard chines) I simply took the “dental floss” and using pliers on each end to keep fingers safe, simply “sawed” the floss back and forth while pulling toward me. The wax on the line/string acts much like a saw blade and it is easy to cut the bulkheads loose from the building plate. Once all are loose, I turned hull over and removed the foam block remains, and finally sanded all foam from bulkheads. I have since switched to a wood building board and use tape to cover th edges of the bulkheads to be removed, and no tape so the panels can glue to the bulkheads that are to remain.

  2. Normally the deck line is kept straight by the cut panels. If not, glue in a small 1/8 x 1/8 or 1/4 x 1/4 strip of balsa along inside edge of each gunwale (where deck and sides meet). Then use a long board with coarse grit sandpaper and sand down so both sides are level. The added benefit is that the remaining balsa inside on each gunwale will aid in gluing deck to hull using thickened epoxy (my recommendation).

  3. Can’t respond to #3 - but check the Simpatico build log for photos and alsk questions there.

I don’t know if this helps or not, but in dealing with my Simpatico build where the bulkheads
and stringers are soft balsa wood and the panels are hard ply wood I use masking tape to
keep from sanding them beyond there original shape. see pictures.

  1. shows that the side panels need to be sanded down to be flush with the formers.

  2. shows how I use masking tape to keep the sandpaper working where you want it to.

  3. shows my sanding block in the general manner I would use it.

I go thru allot of tape and redo or move it as necessary .
This is a technique I have used on models for a long time, don’t know were I got it from.

Hope this helps


Thanks guys, apologies for the late reply, busy building/moving a recording studio…not fun.

The dental floss worked brilliantly, and I have a constant supply of Hi-E guitar strings that will work a treat too :devil3:

Kurt - so basically cover the sections that are fine and keep replacing that tape as it gets ground down?

And with regards too bulkheads - when using balsa I’ve had the grain running horizontally. Correct? I assume most stresses would be from the sides as opposed to a vertical force?