Jump to content
gerard

Stainless steel quality

Recommended Posts

One of your competitors seems to have lots of problems with stainless steel parts rusting. It seems there are more and more problems as their cookers are starting to age. There have been allegations that they have used (and still use?) woefully lousy steel in the past.

You have great photos of your metal parts and they certainly seem robust in comparison. But do you use a higher grade of stainless steel? How about in your "standard models?"

Will you guarantee it will not rust?

TIA.

Link to comment
Share on other sites

FYI

One of the problems that plague anyone who uses SS is carbon contamination. All it takes is to use a carbon steel brush wheel to clean up a weld, a little moisture and rust will develop real quick (although it is just surface rust). A simple cleaning with the proper brush and the problem is solved. I had problems with mine on the very same issue. As you mentioned, there are also different grade of stainless with varying amounts of nickel added to it to give the stainless steel it's stainless properties. One quick magnet test will tell you if it is lower grade stainless as it is magnetic whereas higher nickel stainless the magnet will fall right off. But this is not a quality check as they are made different for strength reasons. Maybe cheap quality made stainless steel was an issue for some on the other grill? My issue was simple; they were clueless about carbon contamination and obviously welding after having to patch up some of their mess (another story there). There were other properties of stainless they were uninformed of too. For example: high coefficient of thermal expansion (almost double that of carbon steel); they allowed 1/4 round grill bars to extend over the outer support which jammed into the side walls causing the bars to bend wildly and lock the grill grate in place till it cooled. But that was a simple fix of grinding them down.

-=Jasen=-

Link to comment
Share on other sites

Stainless quality...

Hi Gerard,

The quality and price of stainless has to do with the nickel content. Type 304—the most common; 18/8 stainless steel contains composition is 18% chromium and 8% nickel. This makes such steels non-magnetic and less brittle at low temperatures. Lower qualities have less nickel and magnetic.

Being that I live and produce these cookers in a third world country I'm constantly amazed at the resourcefulness of people in finding ways to cheat me :lol:

A few cents here, a buck there all add up to something in a country where 40¢ gets you a decent filling meal.

A few years ago, I purchased a couple of boxes of "imported stainless acorn nuts" only to find that when exposed to water they achieved a lovely rust colored patina :wink:

Today I went through my factory with a magnet and was very pleased that out of 50-70 pieces in the rack the magnet was not interested in any of them.. I did although find some cut pieces that go behind the handle that did.. Yikes :o

Looks like we need to have a magnet at the truck during deliveries...

But after doing a little rust research and was very surprised that contamination not low quality stainless may be the culprit..

Here is a lot more about stainless, rust and corrosion than most of you will care to read but I of course found it fascinating...

Looks like I'm going to have to segregate my shop.. and work on contamination...

Almost everyone who makes stainless steel products finds that they rust occasionally. That upsets users since they have paid for “stainless.â€

Link to comment
Share on other sites

Re: Stainless quality...

The quality and price of stainless has to do with the nickel content. Type 304â€â€the most common; 18/8 stainless steel contains composition is 18% chromium and 8% nickel. This makes such steels non-magnetic and less brittle at low temperatures. Lower qualities have less nickel and magnetic.

Hmm, sounds vaguely familiar? hehe 8) It also increases it's shear strength while reducing it's tensil strength. I like to call it gooey metal. Tuff as hell to cut through unless you have a plasma, water cutter, laser or a lot of patients and determination.

But after doing a little rust research and was very surprised that contamination not low quality stainless may be the culprit..

:shock::o

Looks like I'm going to have to segregate my shop.. and work on contamination...

I completely agree. At my work, we must keep all stainless segregated and also the rack they are placed on has to be made of stainless or at least have stainless sleeves. We have to be cognisant of any materials that come in contact with the stainless: fasteners, cleaning / grinding devices and chemical agents. Chlorides will cause stainless to pit and be subject to corrosion too (ie: certain types of tape).

One more interesting carbon contamination from personal experience; even though it made perfect since afterward (hind sight is 20/20), I had some stainless kegs I converted to brew kettles that I took to get sand blasted (thank God just the outside). Well after I started using them, I noticed rust everywhere. Not thinking about this fact, the weld shop uses their blaster for every type of metal and the blaster uses a frit reclaimer - DUH! That was a lot of work fixing.

-=Jasen=-

Link to comment
Share on other sites

Gallery

Here ya go Porkchop! Opps, I thought you said gallery - my bad!

-=Jasen=-

PS - obviously I could give a crap about carbon contamination at home (looking at the photos below). But in reality, it would take way more than my lifetime for corrosion from the metal stand to affect the beer being brewed inside (that and the keg has a huge lip at the bottom which lifts the vessel completely away from the carbon). I just hated looking at rust all over the sides of the kegs; so I had to clean that up. Oh and there is no corrosion on the inside where it counts. :wink:

It ain't purdy, but man it does a good job. Oh yeah, I did not have a plasma, water cutter or laser - so yeah it was a pain.

DSCN0557small.jpg

Ah, cool you sweet nector known as wort!

DSCN0558small.jpg

This is an old photo of the wine press, I have added a stand to it and a cover.

Press1.jpg

Nobody tell the revenuers - ok - hehe - :lol:

Link to comment
Share on other sites

Re: Gallery

Yeah sweet! Wort is unfermented beer.

ok then' date=' drink some :shock:[/quote']

Actually been there, done that! Prefer the later version where the sugars are replaced with alcohol though - hehe! :wink:

-=Jasen=-

Damit, we did it again. We're gonna piss Dennis off having to constantly move our hijacked threads!!

Link to comment
Share on other sites

Yup!

Since I do not have a stainless coal basket, I will have to let Dennis answer that for sure. But what dealings I have had with stainless in the fire area is any metal is gonna degrade in those conditions. I mean, you are talking a couple thousand degrees heat and plenty of caustic ash. Stainless might make it last longer, but size of the metal would seem to be the biggest benefit in a coal basket.

My 2cents!

-=Jasen=-

Link to comment
Share on other sites

I do not think we will ever have to worry about burning out Dennis's coal basket. Just my opinion, but at the rate it would corrode, it would seem to me that it should last as long as the grill. Porkchop just asked if it would rust - and I think yes it will certainly corrode. But not where we would ever care. I still have a carbon steel basket and I cannot see needing a new ones for many years.

-=Jasen=-

Link to comment
Share on other sites

Wow, Dennis, thanks for the very thorough answer to my original question. Seems my questions keep you on your toes and make your write essays for answers. :lol::lol::lol: Glad you learned something in the process and that your product may improve because of it... just never expected you to have to run through your factory with a magnet.

BTW, I recall my defunct cooker's SS failing the magnet test.

I wonder if your competitor has improved their steel since. Perhaps some readers can go perform a magnet test and report back.

I have an engineering question follow up though...

Your photos comparing your damper top assembly with your competitor's are very impressive: http://upload4.postimage.org/154006/photo_hosting.html

But some folks on the other forum, discussing possible solutions to their cooker's problems with the bolt and nut of their dampers rusting seem to authoritatively dismiss the notion of a stainless assembly as being very prone to seizing:

http://www.kamado.com/discus/messages/3 ... #POST45184

Assuming they know squat... and they do seem to speak authoritatively, is your unit not prone to SS on SS seizing (if such a thing exists)? Or are yours exempt from this phenomenon because they are machined with such robust deep wide threads? Or are those folks full of hot air?

Have you had any reports of your damper tops becoming tough to turn? Have they truly proved to be maintenance free?

Drunk_J, feel free to chime in here... it's good to have our own resident expert.

Once again, TIA.

Link to comment
Share on other sites

My guess is that he eliminates this by using acme threads. They are large and roomy threads that should allow for the thermal expansion. I will say that I have galled many a nut or bolt (standard threads) due to the thermal expansion after welding on them as you have to be quick (but were talking loads more heat). Acme threads are very strong threads, but they are also very course. It could make adjusting the top damper not as precise. Curious what Dennis says about this. :?:

-=Jasen=-

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



×
×
  • Create New...