Home made sink

[Fintan]

Thanks for the info Sile. I think my father-in-law uses that company, he has restored a big boat.

I wonder if I would be too ambitious to try to make a sink for my wet bench which is 128" long and 30" wide. It's really L shaped with another bit 33" long again by 30". Maybe the L bit would be too much trouble. The bench top itself is a fairly solid formica kitchen counter.

This really has me thinking

 

[Síle]

I just finished our 40ft sink with West Systems,, great stuff goes down really well no stink , three coats and your printing.

I wanna go live with Bob


Síle

 

[pesphoto]

Im thinking of going about 8ft long and 36" wide. Even considering an L shape as well, but it might take up too much space and I dont think I need to go that big.

 

[Síle]

The latest on the West systems epoxy is that you need a coat of epoxy followed by a 2 pack paint system followed by an interim coat of paint.. all coming in somewhere in the region of €40 + VAT per coat but they don't recommend MDF as a base..
So I'm back to where I started unfortunately.
Has anyone ever tried Perspex to construct their sink? If so I'd be very grateful of any advice.

Síle

 

[Dinesh]

I wanna go live with Bob


Síle

No you don't!

 

[dferrie]

Has anyone ever tried Perspex to construct their sink? If so I'd be very grateful of any advice.

Perspex is not an easy material to work with, it can be difficult to cut as it is fairly brittle and can shatter when being cut. Getting an adhesive to put it together is not always easy either. Added to that it can be bloody expensive. There is a company I know in Newtownmountkennedy who specialise in working with perspex, they may be able to suggest an alternative, but they would certainly do the cutting for you.

David

 

[Fintan]

Sile would you not go back to marine ply?

 

[Bob F.]

Did you price the fibreglass option? If it's not too expensive it would seem the ideal solution. Using fibreglass tissue embedded in resin means the MDF just provides the mechanical support and it does not matter if it flexes a little as the fibreglass will take it.

I'd be worried that any kind of thin coating such as paint would not stand up to the inevitable flexing where two sheets (three in the corners) meet at right angles (but then, I have a one-piece plastic moulded sink so I'm not exactly an expert on the matter...).

Good luck, Bob.

 

[Jon King]

For yet another idea for Síle or anyone else: the membrane roofing material used for horizontal roofs. To do it economically, you might need to know a roofer and get what for him might be scrap. The joints are 'welded' together, and can have standing water on them. Ice and rain shield material used on sloped roofs might not seal well enough - it doesn't seem to be recommended for flat roofs.

If you were worried about wear, you could run strips of thin wood or plastic that trays could rest on. The strips would also have the advantage of keeping the trays out of any (cold) running water.

I am following this thread with great interest, for my own sink project is in the future. When all is said and done though, I think a couple of coats of a marine finish will serve a personal darkroom well. Perhaps a coat or two more if I used MDF.

At a local art school where I take courses, the darkroom sinks lasted several years with just paint before any gouges showed up from constant daily use. I think I'll be repainting my house far more often than I will my sink.

 

[matti]

Why? Epoxy would be a perfectly good finish by itself. It is really hard and abrasive resistant and it also has resistance against chemicals. The only thing to watch out for is lots of sun light, but your dark room is dark, no?
You would have to make sure you get epoxy everywhere, though. As I said, round any sharp edges and make filets where the mdf-boards meet. It would be best to also use glass fiber, but I think it might work without. Also, apply the epoxy coats with no more than 24 hours between them, otherwise you need to wash with water and sand between coats.

If you decide to make a new sink in plywood, you don't need marine grade stuff. But use something with few voids between the layers and a smooth finish, like birch. Don't use fir-plywood.

/matti

The latest on the West systems epoxy is that you need a coat of epoxy followed by a 2 pack paint system followed by an interim coat of paint.. all coming in somewhere in the region of €40 + VAT per coat but they don't recommend MDF as a base..
So I'm back to where I started unfortunately.
Has anyone ever tried Perspex to construct their sink? If so I'd be very grateful of any advice.

Síle

 

[CBG]

Why? Epoxy would be a perfectly good finish by itself. It is really hard

That's the issue, hardness. Hardness translates into a tendency to crack and break. Epoxy is a very, very good material, properly used. Thin coatings, unreinforced, are not a recomended use.

Epoxy is, in this sort of job, properly used as one component in a composite material. Composite materials of this type deploy the complementary strengths of multiple materials to create a new material better than it's parts.

The whole reason epoxy is reinforced is to take care of the hardness / brittleness. and give the composite material the monolithic nature and compressive strength of the epoxy, and the ability to take impact and the tensile strength added by the glass fibers.

If epoxy was tough enough on it's own, reinforcement would not be common. The same logic results in the reinforcement of concrete. Concrete is a great material, and it has great compressive strength, but it does poorly under tensile loading and under impact. Steel mesh within a concrete plate gives it the strengths it lacks on it's own.

A sink will be impacted by every item that gets put down on it, and any item too sharp, or placed too heavily, will fracture the epoxy coating and let liquids get trapped into the MDF, which has very minimal resistance to degradation from water. It just takes one small crack. Once a little water gets in, it swells the MDF, which will further crack the expoxy coating. It becomes a self degrading system. An unreinforced epoxy coating is a much less than ideal companion for MDF in a wet environment. MDF needs full time babysitting.

It might work, but I wouldn't do it that way myself or suggest anyone else try it, without at least trying to communicate the likely mode of failure. The glass fiber is far cheaper insurance than ripping out a sink to re-do it. I think it's false economy.

C

 

[matti]

I do agree with you. As I said, it would be best to use one layer of thin glass. But it might work with only thick epoxy coatings. What I don't agree with is the earlier suggestion to use other paints over the epoxy. It is unnecessary.

/matti

That's the issue, hardness. Hardness translates into a tendency to crack and break. Epoxy is a very, very good material, properly used. Thin coatings, unreinforced, are not a recomended use.

Epoxy is, in this sort of job, properly used as one component in a composite material. Composite materials of this type deploy the complementary strengths of multiple materials to create a new material better than it's parts.

The whole reason epoxy is reinforced is to take care of the hardness / brittleness. and give the composite material the monolithic nature and compressive strength of the epoxy, and the ability to take impact and the tensile strength added by the glass fibers.

If epoxy was tough enough on it's own, reinforcement would not be common. The same logic results in the reinforcement of concrete. Concrete is a great material, and it has great compressive strength, but it does poorly under tensile loading and under impact. Steel mesh within a concrete plate gives it the strengths it lacks on it's own.

A sink will be impacted by every item that gets put down on it, and any item too sharp, or placed too heavily, will fracture the epoxy coating and let liquids get trapped into the MDF, which has very minimal resistance to degradation from water. It just takes one small crack. Once a little water gets in, it swells the MDF, which will further crack the expoxy coating. It becomes a self degrading system. An unreinforced epoxy coating is a much less than ideal companion for MDF in a wet environment. MDF needs full time babysitting.

It might work, but I wouldn't do it that way myself or suggest anyone else try it, without at least trying to communicate the likely mode of failure. The glass fiber is far cheaper insurance than ripping out a sink to re-do it. I think it's false economy.

C

 

[Bob Carnie]

If you make the wood sink in such a way that parts can be taken out , West Systems is the way to go, We have one sink where we cut on the epoxy itself, when the cut marks are too much we, just sand the area and apply more West.
I don't think it needs to be any harder than this unless you are using the sink for a permanent water bath or green house for plants.

Sile , I cannot recommend this product enough.

happy printing

 

[bdial]

MDF wouldn't be an ideal substrate for the epoxy, but it should work, and it's what you have already. It is very prone to excessive swelling if it gets wet, so it would need protection on all sides, and a precoat of some sort of sealer under the epoxy might not be a bad idea. For the non-working surfaces, a good marine varnish should work well.

 

[CBG]

I do agree with you. As I said, it would be best to use one layer of thin glass. But it might work with only thick epoxy coatings. What I don't agree with is the earlier suggestion to use other paints over the epoxy. It is unnecessary. /matti

Ditto on that: paints over epoxy are not a first choice. Most paint products have far less strength than epoxy, and there can be adhesion issues if the materials and surface preparation are not just right.

If you wish for a colored surface, there are tints and pigments that can be mixed in with the epoxy to create an integrally colored surface.

C

 

[Síle]

Thank you to everyone for taking the time to answer my question. There is a wealth of knowledge here, and subsequently a huge diversity of ideas. Unfortunately I have my hands tied as the sink has not only been made out of MDF already, but is currently in situ in a counter-top and work-surface.

Bob, thank you, I appreciate your advice knowing you've constructed some huge sinks (remember if that vacancy in your house ever comes available...) I'm sure West systems is an excellent medium, however their agents here didn't recommend using MDF to me at all, which brought me back to square one. Maybe when I build my next darkroom...

Matti, the suggestion to use paint over epoxy was that of West System's agent in Ireland I appreciate your saying it wouldn't be suitable, but I'm simply passing on the information made available to me.

Jon I do intend to use a couple of coats of Marine varnish on the existing MDF, and hopefully as you said, it should be sufficient for a personal darkroom.

Bob F I did some research on the fibre glass option, but it was turning out to be elusive and expensive. The MDF as a base however is the premise I'm counting on for the finished sink!

CBG thank you for your obviously very informed advice. I appreciate that you wouldn't recommend or do it this way yourself, but as I explained, I'm working backwards and therefore am limited with my choices. For others out there who have yet to embark on their sink making, yours was extremely detailed and helpful, thank you.

Bdial, Fintan and David thank you for your advice and taking the time to answer the thread, they were all helpful and even if not the solution to my problems, I'm sure someone out there will benefit in some way.

As for the outcome? I've decided to go with a Perspex insert sink into my MDF base. A 4x4 sheet costs just €40 and an adhesive called Dead Link Removed which was recommended to me as an adhesive and sealant suitable for aquariums.
If I spring a leak within a short space of time however.. you all have my permission to say "I told you so".

Thanks again to everyone,

Síle

 

[Bob F.]

This reminds me of the old joke: woman pulls up in her car and asks a guy for directions to her destination. He thinks about it for a few seconds and says: "If wanted to get to there, I wouldn't start out from here"...

Good luck! Bob.

 

[CBG]

CBG thank you for your obviously very informed advice. I appreciate that you wouldn't recommend or do it this way yourself, but as I explained, I'm working backwards and therefore am limited with my choices. For others out there who have yet to embark on their sink making, yours was extremely detailed and helpful, thank you.

You are most welcome. Some of my "I wouldn't do it that way" information was directed to some degree to various other folk's remarks, as I am aware you have an existing sink base you just wish to make water proof. I wanted to be clear for the record that the MDF substrate needs to be well protected.

It is most gratifying that you have taken the time to respond to the various posters individually. It gives a better sense that whether or not one's advice is taken, it was all indeed heard.

Thanks!

C

 

[Steve Smith]

As for the outcome? I've decided to go with a Perspex insert sink into my MDF base.

That seems like a good idea. A local swimming pool here was 'repaired' temporarily with Perspex sheets.

You should also consider ABS sheeting as it would be easier to cut. All you need to do is score it with a knife along a straight edge then fold it over. It can be joined with acetone or a solvent based adhesive as is used for ABS waste pipes.

Post some pictures when it is done.


Steve.

 

[Fintan]

Perspex sounds a great idea Sile, how is it working out cost-wise?

 

[Síle]

Bob.. that's my kind of joke and I will certainly need the luck so thank you!

CBG I absolutely understand your advice was to essentially to others, which is why I wanted to make it perfectly clear that just because something might not work for me, it could be the solution to other's problems. All advice is good advice.. to someone.

Steve thank you for letting me know about the swimming pool.. if they can do it on that scale (even temporarily) then it should work for me! And yes, of course I will definitely get some photo's up when it's done.

Fintan.. so far it's working out at :

• €18 for an 8x4 18mm sheet MDF

• €34 for a 4x4 4mm sheet of perspex

• €14 for a 310ml tube of Trans Clear adhesive

• €25 for outlet and waste

• Advice from Apug members ..priceless

A grand total of €91 not including paint/varnish to seal the MDF before I start. So all told my 4x2ft sink will come in at under €100..

Síle

 

[Fintan]

sounds great Sile, let me know when the darkroom warming party is on, i'll be over

 

[Fintan]

How much of an angle do you need to get the water to run off and where is best for the plug hole?

 

[Fintan]

How much of an angle do you need to get the water to run off and where is best for the plug hole?

Can I bump this question, if I make a sink from some sheets of marine ply, how will it drain if its too level, can anyone offer some advice? Or am I worrying over nothing?

 

[Edward Rios]

Hi Fin, read all the posts about your sink project. Sounds like its coming along great too! A basic rule in plumbing is to pitch a 1/4"/foot. That may be too much depending on the size of your sink and the location of the drain. Even if it is level, water will seek the lowest point. So you may have to sponge things dry but don't worry too much on this point IMO. Also, you can get excellent water tempering capabilities with relatively inexpensive single handle tub/shower faucets on a budget. Good Luck!!