:wacko:

I must have misread the OP.  I thought he was wanting to line the vessel.  All the tin cups I've ever used were soldered at a seam.  My bad, ya'll.  That's what I get for getting on a forum with very little sleep!

:rolleyes:

Yes and those tin cups were made out of tin plated steel and  you can do your own plating!  It will be a much heavier plating job more like when you re-tin the interior of a copper pot.  You basically clean the inside  very very well heat, flux and swirl/wipe melted tin.  Practice helps---at least for pans it does---but even my first tries were usable just not as pretty.

Hey guys and gals,

I've been coming to this site on and off for the last few years now, and I've always been impressed by people's knowledge and willingness to share it, so I'm hoping you guys could chuck a bit of wisdom my way?

Basically, I've got some whiskey tumblers made from a range of materials. For example, one is made from extruded steel bar and then capped at one end with a gilding metal base (gilding metal being somewhere between brass and copper).

I need to make the inside food safe as it's gonna have whiskey in it. I can't use stainless because the thing is supposed to rust on the outside.I can't use shellac because the customer is a vegetarian. Is there any way I can get around this? The inside of the tumbler is quite textured so whatever coating goes on it, it needs to be able to seal well. Also, I can't plate the inside with silver or tin because the customer likes the way it looks on the inside too..........

If any such magical substance exists, it would be great to know about. But on a more realistic note, if anyone has some kind of reasonable design compromise I could make, it would be great to hear. I did a rummage round in the forums before and didn't manage to find anything that kitted my needs, but if it's already there, I'mm sorry for my poor searching skills.

 

Many thanks in advance y'all.

Rob

so you want a clear food/alcohol resistant liner for a glass?  Have you tried glass?  Have a blown glass liner made for each one?  You charging US$100 apiece right?

Otherwise this sounds like a "I want a 10 pound item that weighs 6 pounds"...

If not a blown glass insert, see if you can find someone to enamel the inside for you. Still glass, but fused to the metal.

And they do make clear enamels.

Enamel on gold, copper or silver is a standard, and probably OK.  I'd be leery of enameling onto steel as the thermal expansion coefficients may not be all that compatible.  A blown glass insert, glued in, would be my recommendation.  Hand wash only, in any case.

Ah, now that would be a fancy idea. Yeah they are around the £90 mark (not that that is worth much anymore!). I might also look into the enamel idea, I wonder if there's any food safe cold enamels around too?

Iron is food safe, the copper and brass is too if no lead is in the alloys used.

Maybe just tin the bottom only?

Make them out of stainless and treat the OUTSIDE so it rusts.

Enamel on steel is rather a standard for old kitchen appliances so the method is known.  When I worked at the Whirlpool plant back in the 1980's they still had one line using real baked on glass enamels that were used in hospitals and labs. They had a ball mill to prepare it and the moon suits for the guys applying it and the ovens to melt it on.

Thomas,

Good point, but I would hazard to guess that the enamel materials might not be the same as those used in enameling "craft" today.  Would certainly be worth testing out before application for the final product.  Careful attention will need to be paid to firing temperatures (to avoid devitrification) and cooling rates, to ensure proper annealing of the glass layer.  Of course you also have the issue with keeping it all in place on the vertical sides of the cup as well.

Might just be easier to find a paint on polymer that would be food safe.  Not completely sure why shellac would be unacceptable for vegetarians (isn't it some kind of bug secretion?), but I don't know that I'd want it in contact with even a minor solvent like alcohol in any case.  Surely there are food safe coatings available that would be OK ((how about this one for example?)

The base would still be exposed gilding metal which would contaminate the liquid after a short while, even if I made the sides out of stainless (plus it makes my soldering more difficult and is harder to patinate). My brain just finally kicked in and realised that enameling the piece would mean all of my solder joints would fail, as they are done with enameling solder and then filled in with Easy Flo silver solder. I told you I'd be a pain. I really do want to have my cake and eat it... Sorry guys.

Ah, sorry Latticino, I didn't see your reply before sending that. I think some bugs get swept up and killed in the process of harvesting the shellac. But yeah, the point about it's reaction with alcohol was also something I'd overlooked. Some kind of spray on polymer would be perfect. The one in your link for example looks perfect! I just hope it's not only available in humongous industry scale quantities... Thanks again though Latticino.

No problem, glad if I can be of any help, as have learned a ton from this site and want to give back where I can.  For smaller quantities I'm sure you can find other sources: http://www.piwine.com/paints.html for example, though these are colored... Or perhaps the manufacturer of the industrial stuff will send you a sample for "prototyping" (works best if you have a business address for your request).

Best of luck with your project

I've made some kitchen utensils lately and I don't know what to coat them with. I want a food grade clear coat but I didn't find much when I researched it. Does anyone have any ideas for a protective food safe coating? 

Thanks!

I don't know of any clearcoats that are food safe. 

You could polimerize oil on it basically like seasoning metal cookware. There are food grade oils you could lightly coat it with. I've heard walnut oil is good because it actually dries to a light coating (and have used it myself with good results) but there is the nut allergy warning with it. Some steel utensils I've made just get a light wipe with olive oil then wiped dryish after. I never seem to have a problem with them rusting between uses. Also food grade mineral oil is safe to use on them. 

Beeswax and carnuba are both food-safe, but not if mixed with solvents. Pure carnuba is too hard to use by itself, but you can apply pure beeswax to a warm (like, cup-of-hot-coffee-warm) piece and buff smooth.

He never did state what they were made from, that can affect the coating choices, I suggest reading the rest of this thread for ideas

Heavy gold or platinum plating works very well; it's my goto suggestion when folks don't include enough information to make other suggestions!

Isn't the best finish for eating utensils; wash, dry and put them away? 

Frosty The Lucky.

I prefer air dry, leave in whatever that things is called that you put wet dishes in and use as needed.  

I will agree to dry steel utensils right after rinse. 

Anvil, I believe it's just called a drying rack for those of us without fancy dishwashers. 

I usually assume plain steel if not otherwise mentioned in a question like blacksmith03s. High or low carbon doesn't matter much. Best bet is to just use stainless steel then passivate. 

Many chefs that use high carbon steel instead of chrome steel, just wash the knife right after use, then quickly wipe the knife dry and rub with a wee bit of oil over the blade.

The knife should be quickly cleaned, especially, after cutting acidic food. Acidic food, (like tomatoes), can tarnish the metal. (= metal oxide surface).

This is no problem. It does not affect the utility of the knife.  But it looks unsightly to some people. But it can be easily polished off.

SLAG.

Can affect the taste as well some high end folding knives a century+ ago would include a silver blade for use with fruit.

If you search on:  silver fruit knife images      you can find some lovely ones and note the ones with the hallmarked blades do have blades made from silver!

440C tended to eliminate the need for silver fruit knives. I think it's the most common commercial knife stainless isn't it? First 440C blade I remember seeing was a dive knife. Nothing foodish stains mine.

Frosty The Lucky.