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RoyJ
 
Posts: n/a
Default How to make "divot" in 1/4" aluminum plate

I can't say I've done that one but the principle is pretty easy: just
use a suitable male and female die. Tonnage will vary with the exact
shape of the angles and clearances you put in there. Large clearances
will reduce the tonnage but make it more difficult to get the clean
lines you would like. A quick calc for 6061-T6 says that it should be
easy with a 50 ton shop press, suspect less would work
http://www.harborfreight.com/cpi/cta...emnumber=46768

Die design is a bit tricky. You need to have a retainer ring to hold the
plate flat while you extrude though the center of the ring. If you don't
hold it flat the plate will 'pucker'

andy wrote:

Hello folks.
I am writing to get some suggestions for making an aluminum deck hatch
for a boat.
These hatches are mounted flush with the floor (deck) of a boat and are
watertight.

I am just in the thinking it out stage, but would appretiate any input
the group may have.
The product I am trying to duplicate is:
http://store.hamiltonmarine.com/browse.cfm/4,224.htm
It is basically a piece of 1/4" diamond tread aluminum plate. This
plate has a series of "dogs" or latches which secure the hatch into a
stainless steel frame. the dogs are pieces of stainless flat stock
attached to a nut which is operated from above the hatch with a socket.
each dog has a corresponding divot in the hatch which serves to recess
the operating nut flush with the top of the hatch. The divots are
approximately 3" in diameter and 3/16" deep.

My question is this: is it possible to make these divots using a
hydraulic press (the sort with the hydraulic jack) and some dies? or
does this type of forming require a punch-press type of sudden impact
to get the desired results?
I have acess to a lathe to make the dies. I would like to produce say 8
hatches with 4 divots each.

any suggestions would be appretiated (including "go buy them you cheap
p.....")
Andy Hall
Lynn, MA