Engineered Smoke - High Quality Electric Smoker

Quick update!

We're going to aim for nine cubic feet of useable space - 24" wide, 18" deep, and 36" tall.

Heating element is going to be 1500W.

The convection fan and element will both be located on the back wall behind a "plate" which pulls air into the fan, over the circular element, and out along guided paths parallel to the back-wall.  This is similar to some foreign convection oven designs.  The entire space will be useable from the floor to just below the ceiling, no complex drip systems (just a full-size removable pan in the base), even heat distribution, simple clean-up, and reduced fire danger.  Speaking of clean-up, we're discussing a clean feature which will peg the heat and moisture systems to help break down any build-up to the point where it can be easily wiped away.

The design is going to require some custom castings, so our machinist and yours truly are currently putting together a micro-scale foundry which will support this phase.  It will allow us to make fast alterations during the repeated design/measurement phase.  An insulated chamber fitted with test instrumentation will be fabricated soon as well.

We'll be posting some concept CAD drawings/animations, photos, and test data over the next few weeks.  This phase is expected to take some time, but there should be plenty of tid-bits to share.

Thanks for reading and offering suggestions!

- Nick

Hello,

Lot's of research, experimenting, and discussion going on related to the design of the convection system - I expect this to go on for at least 2-3 more weeks.

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Ribwizzard - While the smoker size will certainly affect the final price, the difference between a smaller unit and the size we're proposing will only be a matter of $100 or less.  Around 70% of the projected cost to build is tied up in the systems that are largely independent of size (such as the electronics, fan, smoke/moisture systems, etc.).  We're not expecting general consumers who are in the market for an entry-level smoker at the $200 or $300 level to consider this product.  While reducing build cost (and sale price) is certainly being considered at every step of the way, we're not looking to see this product mass-produced and found next to $99 Char-Broil grills at Home Depot.  The quality components we're sourcing and fabricating simply can't be purchased at prices or volumes that permit this, and quality is more important to this design than price (although both are important).  I understand this eliminates the chance of getting rich off QVC sales, but thats not the intent we've headed into this project with.

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Sound1 - I think we're set on the 24" x 18" dimensions for that reason, although depending on performance with the 1500W element we might adjust the 36" down.  We're starting with that height and hopefully things will turn out well.

I hear you on the convection fan concerns.  We're currently eye-ball deep in this portion of the design, and it's consuming all of our attention.  While it might be simple to purchase a unit direct from Wolf / Bosch / GE and point fingers if it fails, we're going to select or fabricate each component of the convection system to maximize performance and durability.  This includes the motor, shaft/coupling, mounting bracket / hardware, seals, and fan blade.  Obviously this process is intimately involved with the main chamber, so it must also accommodate a removable panel that is easy to clean and properly contoured for airflow and heat distribution.  We also look forward to testing how well the high heat/moisture clean-cycle is able to remove residues and build-up.  Of course the fan blade itself will also be easily removable and entirely stainless for clean-up.

As mentioned earlier, we're designing for a standard 20 amp service outlet with a maximum continuous draw of 16 amps to keep with National Electric Code rules.  The UL listing may or may not occur, as it's largely irrelevant for our projected consumers and the large fee will simply increase the cost of the product.  This is a mobile device that won't require an inspector to sign off on in commercial situations, and most home consumers are not going to be using this indoors.  While this may limit large volume purchases from potential government or corporate customers, thats something we're okay with to start.

Cold smoking is definitely an option we're aiming for with a smoke system that is separate and insulated from the main chamber.  Hope to hear more from you as we progress, and thanks for joining in on the thread!

Hey Chef JimmyJ,

It will definitely be a user-selected option to run the cycle, although depending on how well it works we will likely advise people to use it if they regularly use (either on automatic or custom) a cycle which is high-humidity and high-temperature as part of a cooking process.  I suppose worst case scenario is you don't use it for a long time and then cook with the humidity and temps up filling the removable base tray with goo... =D

Hello all!

It's been a couple weeks and I thought that I might give a quick update as to where the team is at.  We've been experimenting with various convection systems - namely torture testing units from Wolf, Jenn-Air, GE, and Bosch (it's been an expensive couple weeks too!).  We're learning what works and what doesn't, shortcuts that (even "High End") manufacturers use to accomplish tasks such as increasing durability and reducing cost, as well as what can be accomplished when we build units by hand in small volumes rather than mass-manufacture.  Quite a bit has been discovered, and we have an elegant design that is slowly taking shape.

Our design is going to feature a dual in-line fan like high-end commercial stoves which has a primary fan in the heated chamber with a secondary fan mounted closer to the drive (outside the chamber) which provides cooling to increase the motor durability.  This isn't as much of a problem with a smoker that should top out in the 300F-400F range, but we're adopting these premium design elements along with an insulation layer to maximize performance and life.

While we've completed some CAD work and have a prototype running, we haven't settled on a motor yet (hopefully later this week) and personally I want to get that completed and assembled before we do any showing off.  As it stands, the primary fan will be removable via a simple set screw, while the entire heater/fan/motor assembly will also be easily removable as a single unit.

Should have some pictures, animations, and possible video by the end of the month.

Quick Update.

We're still here!  Working on procuring some equipment right now, along with discussing design elements that will permit us to manufacture certain components economically - lot's of boring stuff that is necessary before moving forward.

Also, our progress will be slowing a bit as I'm back in school for my final 6 credits to graduate, and our machinist is taking some time to learn some new skills as well.  Aiming to get the convection system finished later this fall.

- Nick

Thanks for the posts, I know I haven't had a chance to update everyone as of late.

Finishing up my engineering degree this semester (in addition to my full-time job), so my time has been gobbled up between those two duties.  Some discussion here and there along with some more planning for the smoke generator, but not expecting to get much more accomplished before mid-December when classes end and I have more time to dedicate to the team.  Aiming to get the heating/convection system finalized next.  Lot's of measurements and cook chamber design to get into.  We're also discussing more chassis design aspects such as the glass door (to allow viewing without opening the door and retarding cooking), and manufacturing the stainless chassis components in a way that economically makes sense.

Ironhorse07 - Our proprietary controller will indeed be PID based for stable operation, but also go beyond this with custom algorithms and a chassis design that work hand in hand.

danresqman - Thanks!  We hope to keep people posted on the progress as we have, and eventually we'll have a website up to go with our registered domain names.  We're definitely planning to go pellets, as these are the easiest to feed in increments that will allow us to start/stop smoking as needed.  It also frees the user to use the pellet brand they like, and even make custom blends for interesting flavor profiles.  I've checked out Kickstarter before, and it's an interesting concept.  The one big negative is the mandatory time frames you must set.  This is important for businesses looking for investment, but runs against our philosophy of taking our time to do everything right.  We don't want to feel rushed in developing any components, as this tends to lead to compromise and the need for drastic revisions.  At it's core this is a project for a group of individuals with certain skills who have full time jobs, rather than a design that must reach certain sales to pay the bills.  This is to be the realization of ideas first, and a revenue generator second.  Horrible business model, but one I think certain people identify with who will likely be our customers.

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So finally finished my bachelors degree in Electrical Engineering!  I was an older student (now 30), so it was both difficult and rewarding balancing a full-time job, school, family, working on the house, etc. etc...  But this means more time in the near future for getting back on board with the smoker project and enjoying some great food!  Our machinist has also enjoyed the "break" (read delay) I've imposed on progress, but it was a necessary sacrifice.

We're starting by getting some equipment for fast metal working over the next couple months that will enable rapid prototyping all in one location.  Plasma cutter, sheet-metal brakes, and a hydraulic press with some specific dies that will make the most of the free time we have.  My wife has signed on for us to take over the basement and install a hood vent.  I also need to wire some larger 240V/30A outlets for equipment.  Eventually this area may become the first staging point for manufacture with CNC functionality to keep costs down.

So we're working on getting a dedicated workshop up rather than ferrying parts to one another's homes to use various equipment.  Not exciting I know, but a necessary step.

Hey fagesbp - Temperature will definitely be automated.  Probably won't have a smoke detector, just variable pellet feed rates which can be set manually or controlled as part of an automated cook process (varying intensity and on/off for different cycles set by the user or controller).  The moisture detection we're still looking into, as sensor effectiveness and reliability will be of the utmost importance.  Without a doubt the unit will feature a boiler with steam injection, but whether this feature is full on / off (offering moisture saturation), or variable with a feedback controlled vent coordinated with the heater and boiler has yet to be determined.  The latter would be much more complex, and needs to be researched further.  The sensor quality and maintenance requirements are the largest concern here.

Some form of wifi based control might be offered as an accessory down the road.  I'm designing the electronics, and plan to make provisions for an easily accessible internal port that will receive an optional module that can be popped in linking the smoker via wifi to a home network.  Still in it's infancy at the moment.

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Still trying to acquire a centralized work area for prototyping and testing... hopefully by the end of February.