Protecting finish of the wooden HLT lid

[nexy_sm]

Hi all guys,

I am making my new HLT of 70L stainless steel pot. My plan is to make a wooden lid but with that idea come certain questions.
If I would glue alu foil on the inner part of the lid, what kind of glue would be appropriate for it?
What kind of finish would be appropriate in this situation? Some kind of oil?
What kind of wooden glue would be appropriate for gluing the planks?

Thanks and cheers, I hope somebody have already had the same doubts

 

[mirthfuldragon]

I'm always leery of aluminum in relation to beer - the pH can damage the aluminum, and potentially leech out the aluminum into the wort itself. Titebond III would work for glue; per their website, "Titebond III Ultimate Wood Glue and Titebond II Premium Wood Glue have both been approved for indirect food contact. For this reason, it is the glue that we recommend for making cutting boards."

As for finish, I would shy away from oils for the risk of getting them in your beer; even non-toxic or food-safe oils can affect the flavor and head retention of the beer. My maple mash paddle is unfinished and I've used it for years. I would be tempted to leave it unfinished. Otherwise a good polyurethane should suffice. Depending on your joinery skills, I would be tempted to skip the glue altogether make joints and design to allow for steam expansion of the wood. YMMV and I am sure there are better woodworkers than I to advise on the issue.

 

[kh54s10]

There are plenty that brew in aluminum pots. I would look online for a stainless steel lid that would fit. If you couldn't find one, I would opt for a sheet of aluminum and create a top out of that.

If you are set on wood, I would leave it unfinished, and no foil on the bottom.

 

[lump42]

Unless for aesthetics and a challenge, why not just buy a stainless lid. It would be much simpler and cheaper.

For a wooden lid, I would stick with using a neutral hardwood (hard maple, beech). I would avoid walnut, oak, or softwoods (pine, fir, spruce). Look at either creating a tongue and groove, or dowel/biscuit/domino joinery. Like, kh54s10 said aluminum in the kitchen/ food handling are generally regarded as safe with normal usage. I would also skip the foil. leave the wood bare or look at a high temp countertop epoxy. The high temp epoxy I've seen are rated for 500F and are food safe. You could coat the whole lid to seal it and minimize moisture expansion.

 

[LittleRiver]

...wooden lid... what kind of glue...What kind of finish... Some kind of oil?...

A stainless lid has lots of advantages, but if you want to try wood here's what I would do. It could be a fun project.

Use a wood that is naturally rot resistant. White oak, teak, cedar, or genuine mahogany would be good. Check the Wood Database for toxicity of the wood dust and protect yourself accordingly (especially your lungs).

For glue, Titebond III should work. West System 105 epoxy with 207 hardener is also really good for wet environments (it's expensive, but it's really good, and useful to have around for other projects).

I would definitely put a finish on the wood, to help inhibit water absorption. Don't use polyurethane, epoxy, or any other finish that forms a surface film. It will eventually crack and flake, and pieces could fall into your vessel. Not good -- those pieces are not food safe.

Mineral oil should work fine as a finish. Give the oil plenty of time to soak well into the wood, then thoroughly wipe away any excess on the surface.

If you're worried about the oil dripping into your vessel, I don't think that's much of a concern. The oil is going to soak into the wood. The oil is not going to want to mix with the H2O condensate that will form underneath the lid. In the unlikely event there are trace amounts of oil in the condensate drip, it's food safe. If there is a trace amount in the drip it's going to be so small that I don't see how it could negatively affect your brew, or you (you can drink mineral oil as a laxative).

If you don't put some type of finish on the wood, it's going to warp significantly when the bottom surface expands as it gets moist, while the top remains dry. Even finished with oil it may still warp some, but if you keep the mineral oil renewed every so often (twice a year?) it should really help in limiting warp. It's also going to be more susceptible to surface mold growth if you don't finish it.

Don't make your inner lip fit too tightly into the vessel, leave room for the wood to expand, which it will do across the grain (not along it). Use a simple construction, where all the grain is running the same direction, i.e. don't attach cross braces whose grain runs a different direction than your main panel. That will cause cracking as the main panel expands and contracts. Just edge glue the boards together, cut to shape, cut the lip, and attach a handle.

For storage, prop the lid open a bit, so any dampness left in the vessel or on the lid can escape.

 

[nexy_sm]

Hi all and thank you for your suggestions,

First of all I missed to mention in my first post that I want the lid to be made of two concentric discs, one that goes inside and one that sits on the top of the pot.
There are now few things I am not sure about:
1. How to connect the two discs? Are screws ok or should I also use some kind of join?
2. When making a cutting board with dowel/biscuit/domino join, should I use the glue at all or not? Omitting the glue might help with wood expansion due to the steam?
3. As far as I can see I am able to buy (here in Europe) Tung oil. They say it is food grade. I also believe the contribution to the final taste of the beer can be probably impossible to notice.
4. Any idea of having some kind of seal on the rim of the inner disc in order to make better seal?

Best and cheers!

 

[LittleRiver]

... How to connect the two discs? Are screws ok or should I also use some kind of join?

Stainless screws and glue. No joinery needed.

When you assemble the two disks, align them so all the grain is running the same direction.

If you want to make it lighter, cut out the inside of your inner disk before you attach it (so it looks like a loop).

...with dowel/biscuit/domino join, should I use the glue at all or not? Omitting the glue might help with wood expansion due to the steam?

Use glue. Omitting it is not going to make any difference in wood expansion.

I would be comfortable making this piece without biscuit/domino joinery, just edge gluing the boards. It's a small piece that won't have to endure the forces that furniture does.