Removing a holding tank -- epoxied in place?

[sona1111]

Hi All,

After some problems with the old marine head and other reasons, I am considering trying the composting head route on my Bayfield 29. As a first look into this process, I am familiarizing myself with the old holding tank system and trying to determine the best way to remove it. It is situated all the way forward in this boat, under the anchor locker.

The immediate issue is that it looks to be bonded to the hull with some kind of epoxy material (?). Pictures below. This presents a bit of an issue, because this is directly attached to the hull (below the waterline), and I am not sure of a safe method to cut it without any chance of hitting the hull fiberglass. I also thought about perhaps trying to use a heat gun to loosen it, but I am also unsure is this would also "melt" or deform the fiberglass hul or in any way compromise it. Does anyone have any suggestions for tackling the removal of this holding tank?

[Rod B]

Check 'oscillating tool' on the web, can be used to cut parallel to a surface. For fiberglass use a carbide tipped tool. Keep a vacuum cleaner running with hose close to the cut to dramatically reduce the spread of irritating dust. Doesn't look as though it would be too difficult to cut the tabbing in your pics. Good luck!

[gonesail]

what he said: it's probably just tabbing that can be carefully cut away from the hull. the question is will the tank fit thru that opening? god knows you don't want to cut up a holding tank inside your boat

[Chotu]

Above is good advice but if it’s not leaking maybe just leave it?

The smells from standard marine heads are from the hoses mostly. Get rid of them an you’ll forget that decommissioned tank is still aboard.

[thinwater]

That is a fiberglass holding tank and may be more trouble to remove than you think. It may be (probably is) bonded on the bottom as well.


Not what you want to hear, but your problems are probably neglected maintenance by the prior owners rather than a failure in concept. Clean, install a new head and new hoses, and I think you will find that all of your problems are gone for years. These problems mostly come from people trying to limp along on old worn-out permeated old stuff. And don't use the cheap white hose. Use Rairitan Saniflex. It won't stink and it is much easier to work with.


The hose clamps should have staggered clamps. Side-by-side they can leak.


If that clearish vinyl hose is the vent, that is the WORST material for a vent. It always stinks, like within months. Use the white stuff for that (because it is the only sanitation hose that comes in small sizes).



The good reason for composting is the absence of pump-out facilities. Other than that, it seems like you have a very good tank.

[Captain Puget]

Suggestion - leave it, clean it, paint it and use it as a form to hold a bladder tank for extra water or fuel?

You may want to line it with carpet to minimize chafe on the bladder.

[Exctyengr]

Before you do anything get ahold of Peggy Hall's book, "Get Rid of Boat Odors" it covers the full gamut of marine heads, head plumbing, odors, maintenance and yes, "composting heads" She points out that composting heads have limited applicability in marine use because of the difficulty in disposing of the liquids in human waste. Now, I am no expert in heads, but Peggy is and, if I were you, I would not want to experiment with an alternative that a known expert says doesn't work well at sea.

[Chotu]

Originally Posted by Exctyengr

Before you do anything get ahold of Peggy Hall's book, "Get Rid of Boat Odors" it covers the full gamut of marine heads, head plumbing, odors, maintenance and yes, "composting heads" She points out that composting heads have limited applicability in marine use because of the difficulty in disposing of the liquids in human waste. Now, I am no expert in heads, but Peggy is and, if I were you, I would not want to experiment with an alternative that a known expert says doesn't work well at sea.

This is an absolutely ridiculous post.

Better not try a GPS, chart plotter, non-cotton sails, non-wooden boat, refrigerator or an anchor other than a fisherman then. That’s your logic.

Not to mention you only listen to “marine experts?” Is this a joke? What makes someone a “marine expert?” Their telling you so? How many years have they lived at sea and how many miles sailed? Ridiculous. Nobody is a “marine expert “ unless they’re selling something. (No offense to Peggy)

Finally, desiccating heads are the utmost in odor free, maintenance free heads. You don’t have a clue because you never had one.

[Chotu]

Originally Posted by Chotu

This is an absolutely ridiculous post.

Better not try a GPS, chart plotter, non-cotton sails, non-wooden boat, refrigerator or an anchor other than a fisherman then. That’s your logic.

Not to mention you only listen to “marine experts?” Is this a joke? What makes someone a “marine expert?” Their telling you so? How many years have they lived at sea and how many miles sailed? Ridiculous. Nobody is a “marine expert “ unless they’re selling something. (No offense to Peggy)

Finally, desiccating heads are the utmost in odor free, maintenance free heads. You don’t have a clue because you never had one.

This post is even more ridiculous. Sorry. It came out very confrontational. It wasn’t supposed to be so attacking in nature.

Please accept my apologies.

[billgewater]

Oh dear! We did fall out of the wrong side of the bunk this morning. Everyone trying to assist and then we have ......

[Chotu]

Originally Posted by billgewater

Oh dear! We did fall out of the wrong side of the bunk this morning. Everyone trying to assist and then we have ......

It might be that I did not wake up in a bunk at all. Ha ha ha.

Stuck on land for 6 weeks.

Again, I apologize for the idiotic post. I was actually arguing with someone else in a work sense and the emotion bled into my post.

I don’t know if anyone has experience something like that before?

Feel free to delete this whole mess if anyone would like.

[billgewater]

Originally Posted by Chotu

It might be that I did not wake up in a bunk at all. Ha ha ha.

Stuck on land for 6 weeks.

Again, I apologize for the idiotic post. I was actually arguing with someone else in a work sense and the emotion bled into my post.

I don’t know if anyone has experience something like that before?

Feel free to delete this whole mess if anyone would like.

Totally understand. On land for 6 weeks would test the rationality of anyone!

[sona1111]

Hi Everyone,

I appreciate all of the suggestions and replies -- sorry for now being online for a little while -- life -__-.

In any case, as you may have guessed, the lack of pump out facilities at my current location is a large motivator for the change, I have needed to travel relatively far to get a pump out, making the current head basically 'emergency use only'. Recently, the hand pump seems to have stopped working in general, which is why I am looking to replace it now. Oder / smell has actually never been any issue with it before.

I agree that I don't technically need to remove it, but it is a relatively small boat so the wasted space is a bit of a pet peeve. The current anchor locker is pretty underwhelming so I had some vague plans to use the space to build a deeper one. Also, I'm not sure how I could ever verify if I cleaned the tank properly to re-use it for another purpose, so that seems a little dicey.

I'm thinking I will look into this 'oscillating tool' as a potential safe method to start cutting. If I end up needing to chop it up in place, I guess I will just need to grin and bear it

Thanks again for the suggestions all, I'm glad I didn't try to use heat.

[sona1111]

Hey all,

I'm just going through a few old posts and making some closing remarks that the next readers will hopefully find useful.

The recommended "oscillating tool" and carbide attachment were extremely useful for this project. Many thanks for this suggestion. I cut along the marked areas in my original photo. After cutting through all of them, the tank was indeed free and I could move it. However, actually removing it took a few on and off days of alternating a power saw and the oscillating tool to carefully take chunks off and not damage the hull. It was quite a struggle but I feel the extra space I have now is worth it.

I used a box of kitty litter to fill the tank with before I cut too large of a hole in it.

Thanks for all of the suggestions, everyone!

[peghall]

Please don't put words in my mouth! I've never said that composters don't work well at sea...although I have said that they can be problematic. The need to collect urine separately from solid waste can be challenging as can disposing of it legally inside the "3 mile limit." The need to carry bio-starters that accelerate breakdownand dry material to absorb the liquid in solid waste require a place to store it...and if you don't use either one or the wrong one, you have a "box" full of nothing but solid waste. And while they can work well in moderate or even tropical climates, because they rely on bacterial activity, which starts to become very sluggish below 70F and ceases at 40F, they aren't recommended fr live-aboards where winters get cold. And an increasing number of coastal towns are banning bags of not-even-close-to-composted material from their dumpsters.

So while "composters/desiccators" CAN work quite well at sea, they are not just "collect it and take the bag ashore" systems...they require a good bit of effort and a whole different approach to body waste disposal from traditional marine sanitation systems.

But, to each his own, so go with whatever floats YOUR boat for YOU! And if you do opt for composting, spend the money for the best ones...the cheapest are little more than kitty litter boxes.

--Peggie