Possible to convert Survivor 35 to electric power?

[newhaul]

Here ya go a new old 35E for 1850 or possibly less PUR Katadyne Watermaker Survivor 35E Desalinator 12volt | eBay

[newhaul]

Originally Posted by Tellie

Great, I have to admit, it looks a lot better engineered than I was imaging in my mind. Send me a few more pics a different angles and I'll show the boys at Katadyn.

Halden Marine Services – Marine Watermakers, Solar Panels, Wind Generators

Would love some of those pictures myself I have a 35 that I would love to convert .
Your job looks as good as the factory original on our Spencer did

[liberte]

Pizzazz, I enjoyed reading about your post about converting the watermaker. When you have time, could you please share more information about how you put the system together. Thanks!

[BandC]

Pizzazz, I have also enjoyed reading the post about converting the watermaker. With survivor 35 watermakers available from about £250, this conversion makes a lot of sense. If you could provide more detailed information on the build that would be really great. Many thanks.

[boatnerd]

Nice work on the conversion! I had one of the original Pur powersurvivor 35 a while back. I also recently bought one of the $250 surplus manual Katadyn 35s on eBay for the ditch bag, what a deal. Mine too made good water, 250ppm. Since the Pur I've had an Aquamarine AC unit (power hog) and currently an old Village Marine LW DC 6gph with regular 2521 membrane($140 Applied Membrane). If you like to tinker there's lots of ways to do it cheaply without resorting to buying a brand new unit. My current setup including spares(30filters) has cost me under $500. .

[Pizzazz]

Dears,

Sorry for the tardy reply. On the Survivor 35 conversion, the key components are the motor (https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1) and the reciprocating saw, a Dewalt DC385B from Home Depot. You could use any reciprocating saw as long as the saw travel is 1 and 1/8" which happens to be the travel of the manual watermaker piston. I also advise to get a pwm control circuit to be able to vary the motor speed. Also, refer to the ereplacementparts.com site for a schematic of the reciporacting saw mechanism when you work on the conversion.

Start with the circular saw, disassemble and degrease. Then use a Dremel tool to cut out pieces of the aluminium enclosure that you do not need. Cut the bottom and drill three holes as shown in the picture. The motor will attach through these holes with M6 bolts. You may need to flatten out the bolt heads so that they do not touch the gear. Use nuts to compress the bolts once the motor is in position, roughly aligned with the hole for the gear assembly. Take the gear and spindle assembly and cut it at the thickest part, roughly in the middle. The spindle is 1/2" while the motor shaft is 10 mm. You need to make a sleeve in the spindle and flatten the motor shaft so that it goes in the sleeve. Then put a coupling on top of the assembly. Note that initially I just uses a coupling... it is not strong enough and it would disengage after a couple of hours of run time. Next tighten the three bolts through the gear disk to make sure everything is tight. It helps to run the motor with everything slightly loose and tighten the bolts/nuts gradually to ensure alignment.



Now work on the top part of the assembly that houses the piston. I used 2" x 3" aluminium profile cut to the shape of the plastic part of the watermaker. You need to drill four holes for the attachment bolts (I used rods from Home Depot, 5/16"). Measure twice before drilling, make sure the holes are aligned. In the centre you need to drill a bigger 1/2" hole for the pump piston. Then you take the top part of the drill assembly, position it on the top surface of the profile and connect it to the pump piston. Mark the position with a pencil. Find at least three suitable attachment points and drill holes through the saw upper assembly and the top of the aluminium profile. Use M4 stainless steel bolts. This part is not difficult bit the pressure the motor develops is fairly high and there should be no loose movement at all. Use nuts and counter nuts.

Assemble the two parts and run the watermaker dry for a couple of minutes. Whatever is not in alignment, please align. Then tighten all the bolts to the max torque you can. Next test it with water, at low rpm's first then increase the rpms. For the first couple of hours you need to babysit it, as some parts will get loose but eventually it settles. I should probably do a disassembly/assembly video.

Measured performance: I am still running it with the original membrane it came with (15 years old) and I get up to 1.4 gph at max speed (around 40 rpms). The current is oscillating from 2A to 9A depending on the position of the piston. I average around 4.1 amps per gallon. I believe this would get better with a new membrane. The water quality is around 200 ppm.

Now, before you replicate this project, here are my thoughts. It works based on the initial design criteria. The motor gets very hot but it has not burned out yet. I am a little disappointed with the watermaker itself: it leaks, it has a disturbing noise pitch and it produces very little water. The noise is similar to what you hear in the car with the windshield wipers on... yieng, tuk, yieng, tuk. It is not loud but noticeable. Then, the poor thing has to work nearly an hour to produce a gallon of water. It is not enough. It will not make you forget about saving water. You could run it off a solar panel (possible) but do you want to listen to the noise for five six hours every day? Further You would need to buy a new membrane ($340) and possibly the seal kit ($145). All of this because it is a proprietary system. It does have benefits (small, portable, you can tuck it anywhere) but it is better suited for emergencies.

I am now thinking about producing the maximum amount of water in the shortest time, using standard membranes. The topic has been discussed many times and I believe it is the right way to go. One 2521 membrane could give you 12-15 gph and it costs $170. I am tending towards using an engine driven pump with a manual clutch but have not worked out the specifics. Whatever you decide, AC-powered via generator or engine driven, I think it would be a more satisfying experience as the average boat uses at least 8-10 gpd. You could do this with a two hour engine run every other day.

Regards,
Pizzazz

[boatnerd]

On my Aquamarine unit I experimented with an electric clutch and various mount configurations but ended up abandoning the idea. Was concerned that the belt tension at that horsepower would damage mainbearing/seal on my old Perkins. I know of others that have done it sucessfully. The biggest annoyance is probably belt dust and hot oily engine rm environment. I suppose it's all a tradeoff. . If anything i would try to avoid any plastic components at high pressure, regardless of efficiency. Plastic at high pressure, especially moving parts seems to result in leaks, premature wear and higher maintenance. .
Applied Membranes is a great source for low cost membranes/pressure vessels/consumables. One of the bigger outfits which cater to industry. Their AMI brand is a great value(comparable to Dow Filtec). They actually manufacturer in house.

AMI 2551 - $147

http://www.wateranywhere.com/product...products_id=80

[Pizzazz]

Just wanted to share with the group my findings on Dow membranes and required horse power for reverse osmosis (since now I am building a real watermaker). I will focus on the 2.5" x 21" Dow membrane @ $150 as the most practical size for small boats. The larger membrane is even more efficient.

The membrane output is proportional to its size and the water flow rate (among other factors). Optimizing for membrane life, one should run approx. 2.8 gpm through, which gives 12 gph fresh water requiring about 110A and a 2hp motor. This is quite inefficient. However, later in the application note Dow says for small system installations you could run seawater at a much lower rate down to 0.6 gph at which point the membrane will recover 20% fresh water giving 6-7 gph output. This is equivalent to a 1/3 hp or 20 amps or 3 amp/gallon vs. 10 amp/gallon above. By the way any flow rate between 0.5 gph and 2.8 gph will produce roughly the same output but will impact the life of the membrane.

At the low seawater flow rate, they note:

In the table below, the small commercial systems are typically between 1–6 elements that are either regularly replaced or else cleaned (every half year or year) or performance loss is acceptable. The expected element lifetime is not more than 3 years. This is a low-cost, compact solution for intermittently operated systems.


For me the conclusion is obvious, you run at 3 amps/gallon and replace the membrane every 2-3 years. If you go for the longer membrane or put a few in series then the numbers go to 2.2 amps/gallon. Further, you can rotate the membranes from the last to the first housing every couple of months. I think this is more than acceptable.

A further note on comparing to Spectra which is 50% more efficient (at 1.1 amp/gallon). Why would anyone spend thousands on the energy recovery device and the custom (expensive) membrane that would probably last 10 years on the Spectra, when a new membrane is only $150?

Just to summarize, for DIY watermakers, it is best to use the longest membrane possible, 1/3 hp motor (or 1/2 hp to be safe), run the membrane to the ground and replace bi-annually.


Regards,
Pizzazz

[newhaul]

Any new pictures of the conversion . I just acquired a katadyn 35 and am really wanting to make it powered by solar not my arms .

[sailabroad]

Off topic but I had though of making a mil surplus 35 into a foot pump system like the sea water galley foot pump, just for drinking water, but i calculated it would take about 2mins and 60 handle cycles to make 250 mils of water.

Have you looked on aliexpress? I think there were some very small 12volt high pressure pumps advertised?? Perhaps not 600psi..
I'm also sort of looking into putting together a small sink faucet watermaker.

Does anyone know if all the "reverse osmosis water purification" membranes on alibaba are the same membranes necessary for a deslinator?

[Tellie]

Originally Posted by sailabroad

Off topic but I had though of making a mil surplus 35 into a foot pump system like the sea water galley foot pump, just for drinking water, but i calculated it would take about 2mins and 60 handle cycles to make 250 mils of water.

Have you looked on aliexpress? I think there were some very small 12volt high pressure pumps advertised?? Perhaps not 600psi..
I'm also sort of looking into putting together a small sink faucet watermaker.

Does anyone know if all the "reverse osmosis water purification" membranes on alibaba are the same membranes necessary for a deslinator?

Unfortunately they are not. Salt water membranes are a different beast than the fresh water membrane for home use. The pressures for salt water RO membranes are in the 700-800psi range and home RO pressures are around 35 psi.


Halden Marine Services – Marine Watermakers, Solar Panels, Wind Generators

[Fix]

Just found you posts related to S-35 conversion
I have been working for a while on this
Using a modell brushless motor with inverter and purpose built pcb for speed control.Drive is made of household grinder angle drive.Works great.

[Fix]

More pictures

[newhaul]

Fix looks good more pictures of the mounting assembly .

[Fix]

Parts cost for this prototype : 400 $ + labour
Amp draw : 4 A