Jump to content

Transducer holes part 2

Recommended Posts

Hi again,


For some reason this forum would not allow me to reply to my thread about making holes through a FC hull to install a couple of transducers, so I am asking my follow up questions here. Thanks so much for your replies.


The Epoxy Mortar sounds really interesting. Is there any brand that is better than the others? I googled a sikaflex product this arvo.


Diamond hole saws I am familiar with but these plunger type boring machines are new to me. I'm imagining something that looks similar to a drill press. Can anyone point me to a link for one of these things so I can try and track one down. Is it practical to use one under a hull? I imagined drilling a small pilot hole from inside the hull but making the large hole from the outside in.


And just in the vain hope of saving myself a heap of work (and probably pain) I don't suppose the glue inside type transducers will work through a ferro hull will they? The steel would bugger up the signal I'm guessing.


Thanks again



Link to post
Share on other sites

Hi again jr3. I will start by answering your last question first. I don't think so. I have often wondered that myself. Certainly sound travels well through FC and I had thought maybe a transducer would shoot through. But never tried.

OK, so the drill machine may not be the best idea. Firstly you would need to hire one. They are mega dollars to by. And they are heavy. Personally I wouldn't worry about what that other poster said re the breaking out of the concrete. You will make the edge ragged, but there is no way a huge chink can break away unless the boat has not been built properly. Mesh should keep it all together. I would drill in as best I could and then break the concrete away with a sharp pointed punch.
Yes the Sika product is good. There are many on the market. Are you in NZ? That would help me suggest a product if you are.

Link to post
Share on other sites

Even the big boy hammer drills with an sds max chuck don't usually drill much over 30mm. If the boat is up the hard I would contact a local concrete cutter, they will already have all the drills and cores, and most importantly experience. I've seen a lot of expensive coring gear trashed by people who think they know what they are doing. If you are in Auckland I can recommend a couple. As for sealing, I came across a new product today, a gunnable cement polyurethane( I think, will have to check) for sealing pipe penetrations in concrete structures instead of grouting. Initial cure is 35 mins and gets to about 80MPa, also non sag so handy for overhead.

Link to post
Share on other sites
  • 2 months later...

Interesting thread. I will need to cut a 51mm hole in the hull for exactly the same purpose. I own a heavy duty 240v hammer drill (previously owned by my father, a refrigeration engineer who used it to cut holes in bricks) and managed to buy a hole saw of the right size from the UK. Will let you know how it goes.

Link to post
Share on other sites
  • 2 weeks later...

OK, so just did this a week ago. I had to fit a new Transducer and needed a hole 51mm diameter through the Hull. The Town I live in does not have a lot of choice when buying such tools. My choice was Bunnings and Mitre 10. So off to Bunnings I went (they were closer) and all I found was a diamond hole saw for cutting tiles and glass, made by Sutton. I asked if it would be OK for concrete and the guy said yeah I guess. So $65 later (ouch) off I went to the Boat up on the hard. The instructions said to use plenty of water and not go too fast. I couldn't use water, so with the aid of the battery drill, I went as slow as I could. I also used very light pressure. Just basically let its own weight do the work. It took probably 20min to cut through, but it went nicely all the way through the cement and the steel rod with no problem at all. A lovely smooth sided hole and no wear on the cutter.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...