Larger Holding Tank for Catalina 34 MK II

[cmainprize]

Hi Fredrick
Don't be too disapointed the tank does not fit, the only easy thing when making improvments is spending money, everything else is a pain in the butt.  I still have not pulled my tank out yet, we are still in the water untill the 29th.  I would be interested in trying your model to see if it fits, but  it's not a big deal if it does not.  A custom tank is not much more the the ronco tank, once you pay shipping.  Like I posted before, once my tank comes out it is not going back in.  I will be putting in either a cutom tank or modifying my aft water tank to a holdng tank. 

I hope to get up to the boat one day this weekend, but I am not sure yet.   My personal email is mainprize@bell.blackberry.net

feel free to message me anytime, maybe we can figure it out together.

[Fred Koehlmann]

Hi Cory,

You mention a custom tank is not much more in cost. Where were you looking, also with Ronco? What sort of costs were you quoted?

Cheers, Fred.

[Ken Juul]

I'm not sure how different the MK II boats are from the Mk I, but there is probaby room to add another 10-15 gals to the tank if you cut out the center of the seat, remove the plywood tank end and extend the tank all the way forward.  Once installed, glass/epoxy the piece you cut out back in to support the seat cushions.  Not sure what the extra tankage would do to the boats balance.

[Stu Jackson]

Hi Cory,

You mention a custom tank is not much more in cost. Where were you looking, also with Ronco? What sort of costs were you quoted?

Fred & Cory, from everything I've read from Peggie Hall, Ronco will do almost anything as far as custom tanks go. Not sure why you'd be looking anywhere else.

Ken's idea is very good.  That's what I'd do if it was my boat.  If you are contemplating using the aft water tank, consider some things associated with it:

--- material: is it right for a holding tank
--- reduced water capacity
--- distance from the head for pumping the head to the tank:  this is a very real issue, since head pumps usually can only pump 6 feet

[cmainprize]

Stu,
The very reasons you mention (excluding reduced water capacity) are why I have not changed the aft water tank to a holding tank already.  I removed the aft tank last season with the intent on converting it, but no one can confirm if the plastic is suitable for a holding tank.  But the bigger factor is the distance and height of the aft tank.  The head to tank hose length on a mk11 is about 10.5 feet and the head is almost the same height as the top of the tank.  If I make the switch to the aft tank the hose length increases to about 15 feet and the top of the aft tank is 2.5 feet above the head.  I estimate the head would need to pump up about 4-5 feet then I could slope the hose downhill from there.  I do not think I am going to use the aft tank, besides I really like having all the extra storage space for fold up chairs and fishing rods.   

I would suggest that if someone is going to have a tank made, they should go with someone you can bring a mock up too including the inlet, discharge, and vent locations.  This way you are ensured it will fit.  I am not opposed to ronco, but they are 1000 miles further then the guy down the road who does great work. 

If I was ronco I would just adjust the size of the tank to fit the C34, they would probably sell about 300 of them in the first week.

[Peggie Hall]

from everything I've read from Peggie Hall, Ronco will do almost anything as far as custom tanks go.

Not QUITE true, nor is that what I've said.  Ronco DOES have more than 400 shapes and sizes in their catalog, in addition to all the proprietary molds for a number of boat builders including Catalina for whom they've made water and waste tanks for at least a couple of decades...and they WILL install fittings in any locations and sizes specified by the customer....BUT-- 

Ronco only makes rotomolded tanks...so if you want it for a reasonable price, it has to be one for which the mold already exists. You CAN get a custom one-off tank from Ronco, but if the mold doesn't already exist, you'll have pay through the nose--way more than a custom welded tank would cost....UNLESS you can present 'em with a minimum initial order of at least 20 identical tanks, all from that new mold, all paid in advance.

So if there really is a demand for at least 20 of a particular specific shape/size for which y'all can furnish a drawing, talk to 'em...

[Indian Falls]

Fred,

Have you considered a bit of wood work to accommodate your tank model?
You can raise your seat cushions with a 1-3/8'' to 1-1/2" frame that goes over the top of the full length of your settee.  I don't see the "keepers" in your photos that keep the cushions on the settee, but this would take their place, create a space to accomodate your 1'' shortfall, raise the seating surface not more that 1- 1/2''  It also would have the rabbeted openings for the access panels.   Just a quick thought!  Only down side is congruity through out your salon.

[Fred Koehlmann]

Yes, I have... that was my option #2. It would involve some 2X material so tht it would be raised 1-1/2" with a plywood top supporting the cushions. At least then there would be room for a 1" vent line. However before I pull out all the power tools, I'd like to know for sure that I have no other tank options. Raising the settee becomes only the start, because then the cushions are higher and the back cushions and their anchor snaps. Currently the seats are also the perfect height for our legs when we sit.

Cheers, Fred.

[Peggie Hall]

Fwiw,  it is possible that we could find a better location for a tank, and I'll be glad to help your hunt for one....but you're not gonna find any better TANK option than a tank from Ronco...in fact, it would be hard to find one that's anywhere near the same quality.

[Indian Falls]

Has anyone thought of this one:

Rather than using the aft water tank...

Move the fuel tank to the aft  water tank location. 
Put a custom waste holding tank in the Fuel tank location.
Use the macerator to fill the extra holding tank when the settee tank starts filling up.
You will have two waste pump out fittings on port side.

Getting the 1'' hose back there may be a challenge, it would have to follow the one from the head and then it certainly would have waste inside at the level of the sette tank all the time.  But if you use that non permeable hose, maybe it'll be ok.  The one inch hose should be as large an ID as possible due to pumping resistance and clogging issues.

[Jim Hardesty]

Looking at the picture, it occurred to me that possibly cutting the top opening (of the locker) would allow the tank to be moved inboard and aft.  Both directions, due to the curve of the hull, would give you more height.  Once the tank is in, the opening could be repaired, or a larger cover.  In other words looks like there may be enough room once the tank is in place, but the opening is restricting installing the tank.  May be you could check that out by cutting a corner from the mock-up tank.
Jim

[Peggie Hall]

Has anyone thought of this one: Rather than using the aft water tank...Move the fuel tank to the aft  water tank location.   Put a custom waste holding tank in the Fuel tank location.
Use the macerator to fill the extra holding tank when the settee tank starts filling up.
You will have two waste pump out fittings on port side....

    It's certainly creative...I'll give it that much!

[cmainprize]

I pulled my holding tank this weekend to measure and install the new tank.  I measured the tank capacity when I had it out just for curiosity and it holds 15 gallons.  Not sure how ronco does their math but the real capacity is a less the they say.  Like Fredrick posted earlier the 30 gallon ronco tank is a little big so I am having a custom tank made.  It should hold around 27 gallons.  This will be enough for us to make it at least 7-10 days with between pumpouts.  The cost of a custom made 1/2 inch thick welded poly tank is around $900.00, about double the cost of a ronco tank with delivery.  Seems like a lot but, but it will drop right in, and requires no mods.  I am still considering a stainless tank made locally as well, many of friends use them and have no issues.  A local builder has made lots of them and has a great reputation for quality work.  I will get a quote from them and decide.  I believe a properly constructed and welded stainless tank is bulletproof (small caliber only) setup.  Once I get the price I will know what way to go.

[tonywright]

Re tank size:  I posted on this topic a while back.  I measured 14.2 US gal, or about 12 canadian gal.  I asked Ronco why they published 18 gal as the capacity and they said: we got that from Catalina. Yes folks, the same people that brought you the 12,550lb boat that actually weighs 16,000 lbs plus. Best to check all other specifications carefully if these 2 are so far off the mark...Has anyone discovered others?

Despite knowing that the capacity is wrong, the brochure and the selling specs for both Catalina and Ronco have never been updated/corrected.

Re stainless: I think that Peggy has previously warned against it as not suitable for waste tanks.  Too prone to corrosion from urine.

Tony

[Fred Koehlmann]

FYI... 18 gallons US = 14.9 gallons UK (or Canadian)

So Catalina wasn't too far off on this. That said, I think they included the thickness of the walls (taking the dimensions form the outside for the volume instead of the inside).