Painted Transponder

[oneman]

Hi Everyone,

I'm just in the process of having my new (old) steel hulled boat re-vamped. I'm doing all the painting and scraping now myself, however the initial sandblasting and original coat of primer was applied by spray-gun by the fellow who did the sandblasting. In the process he sprayed over the transponder which is located underneath the hull with a couple of coats of primer. I blame myself as I should have masked it over, but what's done is done.

What I'm wondering now is whether this coat of primer over the transponder will affect the operation of the depth sounder or whether I should try to clean it off with some thinner. Or am I likely to cause more damage by doing that?

Any advice would be greatly appreciated.

Thanks.

[Nausikaa]

I can't answer your question but can give a hint how not to end up in this situation in the future. Vasoline! In the Coast Guard we coated all which was not to be painted with Vasoline and, well, painted it. As soon as the ship was back in the water and under way the Vasoline and paint washed off.

It works on windows too instead of fiddling around with masking tape.

Aye // Stephen

[oneman]

Thanks Stephen,

I've never heard of that one.

I'll try it soon.

[MMNETSEA]

Originally Posted by oneman

Hi Everyone,

In the process he sprayed over the transponder which is located underneath the hull with a couple of coats of primer.

What I'm wondering now is whether this coat of primer over the transponder will affect the operation of the depth sounder or whether I should try to clean it off with some thinner. Or am I likely to cause more damage by doing that?

Any advice would be greatly appreciated.

Depending what was in the primer ie.. if it contained metal like iron oxide or zinc chromate, this could effect readings by the sounding signals being reflected before they get out. If there was NO metal in the primer, leave it on - many transducers inside composite hulls operate fine right through the hull without being inserted in a through-hull.

Therefore if the primer did have metal in it - clean it off - suggest not with thinners as the face of the transducer may be plastic. Use Brasso or some other metal polisher.

[Coyote]

Originally Posted by MMNETSEA

Depending what was in the primer ie.. if it contained metal like iron oxide or zinc chromate, this could effect readings by the sounding signals being reflected before they get out. If there was NO metal in the primer, leave it on - many transducers inside composite hulls operate fine right through the hull without being inserted in a through-hull.

Therefore if the primer did have metal in it - clean it off - suggest not with thinners as the face of the transducer may be plastic. Use Brasso or some other metal polisher.

If your transponder works through a plastic hull (as mine does) and if the bottom pain has metal (No idea) then I would have the same problem. Which I don't. Does this mean I need to carefully avoid metal in my bottom paint?

[oneman]

I had a go at cleaning off the primer with some solvent. Not quite sure whether it worked or not. My question now is does anyone have any ideas on how I can test my depth sounder while the boat is still on the hardstand before I get it back in the water.

Any ideas would be greatly appreciated.

Thanks all,

Oneman

[GoneTroppo]

My depth sounder works with a layer of epoxy and then 2 coats of copper epoxy anti-foul over it. So I expect that some undercoat won't cause much of a problem. Anyway good luck.

[oneman]

Hi All,

Bit late but better late than never!

Finally got back in the water (about 6 months ago). Transponder works fine so the primer coats didn't appear to affect it nor did my attempt at removing the primer.

Cheers everyone.

Oneman