transducer hole size

[csamsail]

I need to replace the DataMarine Dart model 2490. I do not want to drill new holes in the bottom of our 26 year old Wilbur as there are enough there already. Is it possible to find a unit, transducer, that will fit the holes that are already in the hull? I have been on the DMI page, looked at what they have to offer, and would like to move on to a unit from a different company, if possible. The 2490 has a depth transducer and a knot/temp unit. Any suggestions. Thanks.
csamsail

[cburger]

It is generally possible to get a hole saw to match the transducer size and just enlarge the existing hole to fit the transducer you wish to install.

[GordMay]

Originally Posted by cburger

It is generally possible to get a hole saw to match the transducer size and just enlarge the existing hole to fit the transducer you wish to install.

When enlarging an existing hole, with a Hole Saw, you need to provide a temporary plug for the hole saw’s Pilot Drill (Arbour). Clamping a 1/4" piece of plywood over the existing hole is one easy solution to the problem of hole saw “wandering”.

Another technique is to install two hole saws on a single arbor, one inside the other. The larger, outer saw should be the size of the new hole, and the inner saw should be sized to the existing hole and protrude at least a half inch beyond the outer saw.

Chuck the arbor into a drill and insert the smaller saw into the old hole. Then squeeze the drill trigger and carefully guide the saw through the hole to keep the drill on a straight, steady course as the larger saw cuts a new hole around it.

[Chief Engineer]

Ah...the wisdom....who would have thought of that?

I can't wait to try it out ( or "oot")

[bob_77903]

Your get'n that North of the border language down Cheif