Halogen 1400w turbo ovens cheap

Gra

Gra wrote:

I picked one up last week for $39.00 and I have only done two roasts so far it gave a nice level climb rate but it took longer to first crack then my solid element unit by two mins..Early days yet I will do a per heat on my next roast and see what difference that will make I like the way it lights up the beans it makes for good viewing.. Cheers Gra..

Well I roasted again today with the halogen turbo and the thermostat was going on and off every 30 sec with a rate of climb 5-6 sec per min and first crack came in around 15:00min and I pulled the roast at 21min before second crack it appears the max temp was well under 250* about 60*going by the DMM. I took it back and they changed it for a new won I tried it and all is well just hope this unit last for more then two roasts :o Gra..

borat123

Gra wrote:

Well I roasted again today with the halogen turbo and the thermostat was going on and off every 30 sec with a rate of climb 5-6 sec per min

Hi Gra, 5-6 degs per minute sounds a bit slow, unless you were purposely slowing the temp ramp down. What was the batch size - was it a big roast? What drop temp are you starting from? FC at 15mins, assuming a ramp of say 5degs/min suggests you're starting somewhere around 120degs? The last roast I did (1kg Harfusa) had a similar FC at around 15mins, but I started from about 40degs, and have to interrupt to keep the ramp down to under 15degs/min until it gets past about 120degs. Then at this batch size, it sits quite happily at about 10/min. (see profile below) I might do a dummy (empty) roast with my new one and see what it can do. I seem to remember doing temp ramps of more than 20degs/min in an empty KKTO, when I first tested the Tiffany (solid element & before it was modded)

Koffee_Kosmo

I still use the Tiffany I would guess that its getting close to 500 roasts now I will however get me halogen TO just to give it a go I am also considering a Variac for on the fly temp control similar to Borats on off operation KK

Gra

borat123 wrote:

Hi Gra, 5-6 degs per minute sounds a bit slow, unless you were purposely slowing the temp ramp down. What was the batch size - was it a big roast? What drop temp are you starting from? FC at 15mins, assuming a ramp of say 5degs/min suggests you're starting somewhere around 120degs? The last roast I did (1kg Harfusa) had a similar FC at around 15mins, but I started from about 40degs, and have to interrupt to keep the ramp down to under 15degs/min until it gets past about 120degs. Then at this batch size, it sits quite happily at about 10/min. (see profile below) I might do a dummy (empty) roast with my new one and see what it can do. I seem to remember doing temp ramps of more than 20degs/min in an empty KKTO, when I first tested the Tiffany (solid element & before it was modded)

Yes your right on the low rate the first roast I did the rate was 15.16 * with staring out at 23*per min up to120* there definitely was some thing wrong with thermostat just hope the new one doesn't do the same. Gra..

Gra

Koffee Kosmo wrote:

I still use the Tiffany I would guess that its getting close to 500 roasts now I will however get me halogen TO just to give it a go I am also considering a Variac for on the fly temp control similar to Borats on off operation KK

Hi Paul Sorry for not replying last night the Boss came to bed and it was light out ;D ;D The Tiffany sure has proven it's self no doubt about that my original TO is still going strong it's just the switch is about to give up been dropped to many times 😃 I might look at fitting a toggle the Halogen is for a backup just in case I get court out with the old girl. I tried a Variac when I built my new TO to use for motor control but it didn't work properly with a capacity type motor like the bread maker so I took it back didn't think at the time RE temp :-\ Cheers Gra..

Koffee_Kosmo

Gra wrote:

Hi Paul Sorry for not replying last night the Boss came to bed and it was light out ;D ;D The Tiffany sure has proven it's self no doubt about that my original TO is still going strong it's just the switch is about to give up been dropped to many times 😃 I might look at fitting a toggle the Halogen is for a backup just in case I get court out with the old girl. I tried a Variac when I built my new TO to use for motor control but it didn't work properly with a capacity type motor like the bread maker so I took it back didn't think at the time RE temp :-\ Cheers Gra..

I am thinking temp control as you have guessed Have to get an electrician to adjust the thermostat to max, disable the temp switch to allow the Variac for manual temp adjustment by the user Something like this from Jaycar - http://www.jaycar.com.au/productResults.asp?keywords=variac&keyform=KEYWORD&SUBMIT.x=0&SUBMIT.y=0 KK

Gra

Koffee Kosmo wrote:

I am thinking temp control as you have guessed Have to get an electrician to adjust the thermostat to max, disable the temp switch to allow the Variac for manual temp adjustment by the user Something like this from Jaycar - http://www.jaycar.com.au/productResults.asp?keywords=variac&keyform=KEYWORD&SUBMIT.x=0&SUBMIT.y=0 KK

That's the one I had there a good unit wished that i had keep it now 😡 ;D Good idea mate keep me up to date on that one ay. Cheers Gra..

Koffee_Kosmo

I will start a new thread when I get it started KKTO Variac temp control project Will look for used Variacs as well AM do you have any contacts KK

borat123

Just finished having the relay mod done to a halogen TO. Very simple changes with most of the existing harness being left in place. Also required is to plug the hole in the heat shield left by removal of simmerstat - its only small and I used a bit of tin from a tuna can lid, held in place with some hi temp permatex. Here's a pic of the bowl of spaghetti for anyone interested. *** Usual WARNING - don't play with 240V etc *** have it done by an electrician.... Once the silicone is all dry, I'll give it a run and see if it's as good as the modded Tiffany. Thanks to KK, I also bought and fitted a braided temp probe, with the tip mounted on the bottom of the pot. I'm hoping this will help stability of temp readings with smaller roasts.

Gra

Looking good will interesting to see how she performs. Gra..

borat123

Gra wrote:

Looking good will interesting to see how she performs. Gra..

Had a dry run (empty) to get an idea of the heating capability. From approx 38C starting temp, it took approx 4mins to reach 250C, still climbing at 35degs/min. The initial ramp was 85/min! I think it should be at least equal, in terms of heat ability as compared to the modded Tiffany with solid element. The noise from the fan, the amount of air blast seems less, and perhaps the speed is also slower as compared to the other one... Still waiting for the silicone to cure so will put some beans in for a roast tomorrow. Here's a pic of the new braided temp probe & graph of the temp data:

Gra

I like the braided temp probe setup. The other day I was getting some strange readings from the DMM with first crack coming in at 70*. After I finished the roast I checked my probe one of Andys braided k type and found that a steel pin I had made for locking the handles on my roaster was laying on the braid upon removal the temp change by 20* it appears it causing the interference.. :o just something to look out for in future.. Numbers are looking good will be interesting to see how your first roast goes 8) Gra..

borat123

Halogen TO (modded) roast report....... I roasted 1kg Harrar star double sort. The profile looks almost the exactly the same as what I was able to do with the Tiffany. With the element locked on, it was ramping up 1kg at 15deg/min, reducing by itself to around 10deg/min. After 190C, the reduction in the ramp shown is me switching the element to purposely slow it down a bit.I would say the heating capability is the same. The upside though is the heat is a little easier to control as the lag is less with the halogen than the solid element. The view in the pot is a hell of lot better too, now I can see what I'm doing without having to shine a torch in there through the smoke. All up, I think I prefer roasting with the Halogen. Here's the profile. I wanted to pull it a little earlier but was suckered in with strong light thinking it was lighter than it actually was...... It still looks like a nice roast though.

Koffee_Kosmo

It has certainly proved its performance credentials I will be getting a halogen unit with light, cos I just got reading glasses Bloody old age KK Edit I have placed an order for one as per Borats recommendation ;D

RichardM

Koffee Kosmo wrote:

It has certainly proved its performance credentials I will be getting a halogen unit with light, cos I just got reading glasses Bloody old age KK Edit I have placed an order for one as per Borats recommendation ;D

Old age has little to do with it. I had reading glasses until two years ago. Changed jobs to one where I am not looking at a computer screen, and my eyes were good enough to not need them after 6 months.

Aktion

borat123 wrote:

Just finished having the relay mod done to a halogen TO. Very simple changes with most of the existing harness being left in place. Also required is to plug the hole in the heat shield left by removal of simmerstat - its only small and I used a bit of tin from a tuna can lid, held in place with some hi temp permatex. Here's a pic of the bowl of spaghetti for anyone interested. *** Usual WARNING - don't play with 240V etc *** have it done by an electrician....

Hey Borat, I got one of those halogen TO's too. After reading your post I thought I mod it the way you have. So I opened it and noticed the thermostat... I bridged it thermostat (so it's always on), and I stopped there. I haven't bought a relay yet but I wonder, why would I need one? (my electrical knowledge is basic at best). Any input will be greatly appreciated, especially if it has to do with safety. BTW. The timer stays. It plays the role of a power switch, and "fail safe" (in case you walk away and forget the TO on at full blast) Thanks

borat123

Hi Aktion, Happy roasting with the halogen TO but please don't attempt to do any of the wiring for the mod yourself. As I mentioned in my earlier post, you should HAVE ALL THE WORK DONE BY AN ELECTRICIAN....! Someone more electrically qualified than me may be able to explain why a relay is / is not needed for this application. To just jumper the the simmerstat, I imagine you're planning on doing all the switching with A) the on/off handle (?), or B) using the timer [not really practical], or C) at the wall :o I was more comfortable being electrically isolated from the mains / high current, and switching using a low voltage simple switch. This also leaves the fan running whilst you can switch the element on / off at will.

Aktion

borat123 wrote:

Hi Aktion, please don't attemp to do any of the wiring for the mod yourself. As I mentioned in my earlier post, you should HAVE ALL THE WORK DONE BY AN ELECTRICIAN....! Someone more electrically qualified than me may be able to explain why a relay is / is not needed for this application. To just jumper the the simmerstat, I imagine you're planning on doing all the switching with A) the on/off handle (?), or B) using the timer [not really practical], or C) at the wall :o I was more comfortable being electrically isolated from the mains / high current, and switching using a low voltage simple switch. This also leaves the fan running whilst you can switch the element on / off at will.

A. The handle. The timer will -only- act as and an off switch if you somehow forget it on for some reason. "This also leaves the fan running whilst you can switch the element on / off at will." That's a nice bonus. And finally the most important aspect. Safety. My BIR has an electrician mate. I'll take it to him on the weekend, hopefully sometime during the week they'll catch up. (I rather have him take a physical look at the TO rather than verbally explain what I've done). Thank you Borat.

coffeehorse

The KMart Homemaker turbo oven appears to be internally and externally identical, and is on sale without being discounted at $39.95. (IIRC). I'm roasting in a 15L pan, so had to remove the guard, which I think was causing the thermostat to work properly for the type of roasting it was doing. The problem with these home brand turbo ovens seems to be that the guard heats up to XXXC and then the element turns off, then back on when the guard has cooled a bit (eg. it's causing a bigger temperature differential between the beans and the sensor than when removed). In this respect, the Tiffany is a much better unit, But I love the light! Now all we need is a full spectrum 1400W halogen bulb.

Lacehim

The light is good eh. Makes roasting that bit easier. 🙂