I'm working on the finishing touches on an offset-type horizontal smoker that I had custom built, and I'd like to install a strip of light inside the tube, if possible.

My smoker looks very similar to this one:

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My plan is to install said strip inside at the upper part of the main tube, just behind the lid's hinges. Of course, said strip must be resistant to high temperatures. And by high, I'd like it to be able to work at up to 400°C (750°F). The reason why I'd like it to have such a high working temperature is because I plan to use the smoker as a grill every now and then. And that means that charcoal or lumber will be burning a few inches under its mesh, right below where the strip is going to be.

For this purpose, I plan to use miniature 12V halogen lights, and ceramic sockets such as these:

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I'm going to have to replace the wires in those sockets with high temperature type, and for that purpose I already know a couple of suppliers down here in my hometown. Also, I'm well aware that said strip of light is going to have to be cleaned every time the smoker is used, or otherwise grease is going to build up not just on the bulbs themselves, but also on its contacts.

I have not yet worked out how I'm going to assemble the strip itself. Maybe the bulbs could be mounted on an aluminum profile? Or perhaps placed inside a tube of pyrex glass? Also, are there commercially available high temperature cable glands out there?

Any suggestions or observations on my design?

 

How are you going to wire it? THHN wire insulation (for hot service) is only good to 90°C. There is a mineral insulated cable in copper tubing but it's like running very stiff copper tubing. It's used by the Navy and industry for fire safe wiring. Not easy to find, not cheap, and not easy to install but good for ~1000°C. May also require special copper fittings. MICC Pyro Cable MI Cable Fire Surival Cable UL 2196 (miccltd.com)

 

I've been thinking about using a couple of ss rods as electrodes with holes in them where the bulbs could be mounted. And perhaps use screws to firmly press the electrodes in the holes so as to ensure good contact and prevent the bulbs from falling off. Or maybe use a spring like connector instead. The two rods could be attached using ceramic spacers. And power would be delivered from a current limited supply, to keep things safe.

 

Using machine screws on a grill means they expand and contract, tending to work loose. LocTite makes a high temp product for that. Since you are dealing with voltages that won't electrocute someone, you might get away with silicone rubber insulated wiring. Silicone is good for ~300°C.

 

'High' temperature means nothing. What is the temperature it has to cope with ?
If there is something with a chance to survive, may be the miniature 12V halogen you show above with the ceramic socket.

Unless ----> https://www.ecosia.org/images?q=quartz heating elements for heater Some of these are bright light emitters too.

 

'High' temperature means nothing. What is the temperature it has to cope with ?

That info was included in my first post. I'd like it to be able to work at up to 400°C

If there is something with a chance to survive, may be the miniature 12V halogen you show above with the ceramic socket.

Yup ... I was thinking about the same thing.

Thanks for suggesting I look into heating elements. At this point I'm looking for ceramic parts that I could use as spacers and mounting hardware.

 

Well, I don't necessarily have an answer to your approach. However, I'm thinking perhaps have the wiring outside the lid with just the bulbs protruding into the oven cavity. That will at the very least reduce the heat the wires have to deal with AND virtually eliminate the concerns about grease buildup on wires and contacts. Maybe some sort of high temp epoxy can hold the lights in place. But that would mean when changing a bulb you'll have to break the existing one out, clean the hole of epoxy and epoxy a new bulb in its place. Perhaps a little less sightly than having everything inside the cavity, but you could redress the wires outside in some sort of decorative conduit. Conduit doesn't have to be round, or made of galvanized tubing.

Hopefully this may spur some new ideas for approaches in reaching your goal. I have a Traeger grill and wouldn't want all that stuff on the outside, so maybe you don't either. But my grill doesn't expose bulbs and wiring to extreme temperatures the way yours will.

Maybe a miners lamp ? ? ?

 

That info was included in my first post. I'd like it to be able to work at up to 400°C

Am sorry I totally goofed missing to read the properly posted temperature. (redface)

If you find a way to place the quartz bulbs by both end sides vertical walls; would also be 'inside the tube' and simplify mounting. Another way is to canibalize lamp holders from defunct range ovens, they do withstand 400F, not 750F=400C

 

WHAT THE HECK! I was posting on a different thread. How did my post end up here? I've removed the superfluous erroneous answer.

 

WHAT THE HECK! I was posting on a different thread. How did my post end up here? I've removed the superfluous erroneous answer.

You hanging out with you know who again?

 

You could use fiberglass insulated wire to ceramic fixtures (mount sideways so the bulbs don't rub your meat (that's what she said)) and probably just put ordinary incandescent lights in them. Is there a heat spec on those? I mean they're just made of glass, metal, and ceramic right? Is there any solder in them?

 

Sorry I just re-read your post and realized everything I said was pointless. You've already got that part figured out. You were pretty much just asking about high temp glands. Fishing pole eyelets?

 

Put them on the smokestack end and they won't need to be rated 400C

https://www.mcmaster.com/high-temperature-grommets/

 

Put the whole assembly inside a pyrex glass tube, which will make it a lot simpler to clean and also provide adequate insulation. And you can put 11 of those 12 volt bulbs in series and use mains power and not need a transformer.

 

Put the whole assembly inside a pyrex glass tube, which will make it a lot simpler to clean and also provide adequate insulation. And you can put 11 of those 12 volt bulbs in series and use mains power and not need a transformer.

I was already thinking about the glass tube... but there's no way on earth I'm powering the assembly from mains! ... it's a metal grill, after all... safety comes first

 

I was already thinking about the glass tube... but there's no way on earth I'm powering the assembly from mains! ... it's a metal grill, after all... safety comes first

OK, it was only a suggestion, and it could be done safely. But whatever scheme for powering the lights is used, supporting the tube will take some thought. Many grills have a mains powered gearmotor to rotate a spit to cook large items more evenly. And a 3/4 inch diameter pyrex glass tube will be fairly strong and probably rugged enough. Also, using a GFCI device willavoid any shock hazards.

 

Put the whole assembly inside a pyrex glass tube

I think that would be essential, as any grease/oil on the bulb quartz envelope could drastically shorten the bulb life or cause the bulb to shatter.

 

Yes, I think a pyrex tube is definitely the best approach ... (say, I can't find tubes with a diameter larger than 1/2" )

Anyway, the difference between an assembly such as this one and a grill with a gearmotor is that neither the gearmotor nor its wires run directly above the flames.

The pyrex tube assembly would have to be constructed in such a way that it should be easy to dismount for cleaning after every use. And for that purpose I'm already looking into ceramic terminals such as this one:

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Mounting those terminals in such a way that the tube can be connected and disconnected in a spring-like manner is going to be a bit of a challenge.

 

FWIW Pyrex is a name brand. Any borosilicate glass should do. Borosilicate Clear Tubing and Rod | 33 COE | Mountain Glass Arts

 

The connectors will be an issue, since you are running above the melting point of most solders. Much of what I have seen has been welded.

Separate from that, wire. I have used Teflon-insulated hookup wire for decades. I don't know its actual rating. I've hit it with a torch just to see what would happen, and it melted. However, I've sat on it with my fat soldering iron tip and it is fine. It discolors a bit, then returns to the normal color when cool.

Specialty companies like Cooner Wire might have something.

ak