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Hello Bruce, About 22 years ago
whilst living in Cape town I built a Roberts Ofshore 44 (multi chine steel).
Now living in Auckland, New Zealand I have been building the Roberts 370E RC steel for the
last 3 years. I am planing to retire in a few years time and then go full time cruising
till I keel over. I attach some pictures of a clamp which I used to hold the hull plating
prior to tacking and welding. I find these clamp arrangements very usefull and as I am the
only person on the job they were a great help.These clamps were made up as follows. (sizes
were based on available slot punch) Wedge section is ex 5mm plate x 120mm long tapering
from 12 to 20mm. Slotted plate ex 1.5mm plate 35mm x 20mm with a 27 x 6 mm slot punched in
the centre.
pin spot welded in slot 6mm dia x 35mm long. These clamps are used as follows:-
Pull the hull plating up to each side of the slotted
plate and secure with the wedge. This clamps the hull plates together keeping them
level/parallel and pre sets the weld gap at 1.5 mm. Position these clamps as required, at
about 80-100mm crs. When the hull plating is in position tack weld together then remove
wedges and slotted plates. The few slotted plates that get stuck are ground flush
and welded into the joint. I set the stringer at about 40mm off the side of the raduis
chine plate and tack welded it in place. When putting on topside and hull plating it was a
neat and very straight joint using these clamps. I hope that this information will be
usefull to others that are building in steel. Thanks and regards, PATRICK GOLD.
Hallo. Ive received your book
Metalboats and studyplanes of Spray 28 and Tom Tumb 26. That book is a goldmine for metal
boatbuilders.Well I dicide for the Tom Tumb. Thanks fore one of the best
and educating internet sites on the web. Best regards from north of Sweden Lennart
Broman
ATTACHING BULKHEADS TO STEEL HULL WHERE NO CORRESPONDING FRAME
EXISTS ?
QUESTION:
My main question for now is the attachment / location of the bulkheads. If I space them
according to the interior layout there is no way to weld them to the frames as the boat plans
call for, as there are no directly corresponding ones. So do I just weld them to the
stringers or do I build spacers or..?! My apologies if the questions seem like ones
I should have asked sooner
ANSWER:
To attach plywood bulkheads to steel hulls where there is no corresponding frame is a
simple matter. All you have to do is insert a piece of flat bar frame material between
each stringer where the bulkhead is to be located. We call these pieces of frame 'tags'.
The flat bar should have holes pre-drilled to allow the plywood bulkhead to be bolted in
position. Bolts will be 1/4" / 6 mm dia. spaced at say 5" / 125 mm intervals or
spaced to suit length of tag. The section of frame material should be
about 50% in length of the distance between the stringers. The welding of the frame flat
bar should be the same sequence as used for attaching the frames to the hull plating ..
short staggered welds of no more than one inch long spaced say 2
inches apart on alternate sides of the frame flat bar. Snape the ends of these
'tags' so that there will not be any hard spots showing through to the outside of the hull
plating.
CUSTOMER'S TIPS ON USING BRUCE ROBERTS BENDING JIG
Dear Bruce just a little note to pass on a tip for anyone using your
suggested bending jig .the trick I have found is to be systematic and methodical
(good words hope I've spelt them right). Once you have mounted the flat bar in the jig
snug up the jack and then pump the jack a set number of times (I found three or four to be
about right), then release the jack and move the work piece along four inches then snug
the jack up again and pump the set amount as before,do this the full length of your radius
then check it on the full size pattern, if you feel that it is about half way to the
correct profile then go back along it placing the jack in-between the positions you
used on the first pass and pump the jack the same amount if you think that it is more than
half way or less than half way you can adjust the amount of pumps to suit .I messed about
for long enough with my jig till I found this way of working it. Now I'm getting on like a
head sail in a force four. Hope this helps someone.
Yours FRANKIE McGOVERN ..... Glasgow Scotland
Hi Bruce, Here is one of Your 370Cs near the Adriatic
coast (Croatia). Since You were so nice to re-send me "The METAL BOATS", I
decided to Thank You with the picture I really like. She has a registered top speed of 12
kts and has been built in Zagreb,Croatia eight years ago. Best regards, J. Palcic |
![Bruce[2].jpg (4158 bytes)](images/Bruce[2].jpg)
