SC/TO Profiles / Q&A / Tips & Tricks

[J.Jirehs Roaster]

Hi Fellas,

Well, I've been toying with the SCTO idea for a year or so, and finally, at the thrift shop last week, the SCTO gods were looking after me and put a Boxed up Stir Crazy right next to a Turbo Oven right on a shelf. I couldn't resist.

I had been casually looking - again on and off - and this is the first time I've seen either of the two in a thrift shop. They were overpriced (9.95 and 14.95), but bought 'em.

So now on to thinking about this new project.

Question: My SC is from 1977. It looks like all metal shaft. Do I still have normal temperature worries there, that I have seen others talking about? Any other considerations due to the vintage of this model? (yes, it works, though looks like low RPM. What is normal RPM?)

Going to get some aluminum, disconnect the heater, and give it a go. Then think about the stirrer arm. I guess I'll pick up a copper end-cap to put over the shaft, just in case.

Well, off to teach. Talk to ya'll soon. I'm sure some questons will come up soon.....

-Nimbus

sounds like a good price to me...  I really like peter's stir arm mod.. its not that much heavier and keeps the beans moving better that the stock arm.. but the stock arm works pretty good.. my SC is heat off and I preheat to 350F then drop the beans.. they bottom out around 190F and I have to slow the heat down  (lift and lower handle on TO) around 270 if I want to keep under 300F for 6 minutes of drying.. at 350F I lift the handle on the TO to turn off the heat till about 360F when the climb turns to a drop.. heat on again and that is usually 2 minutes of caramel zone (350 to 375) at first crack I start riding that handle to slow down the time in first crack.. then pull off the lid and dump beans in a cooler when I am happy with the sound, smell, temp and smoke..    

WARNING: I have separated the fan and the heat in my TO so the fan stays on when the handle is raised.. so my method may not work with out that modification

I will try that copper cap idea peter.. that's a good one

[peter]

That sounds like a long time under 300F in the drying phase, Wild Bill.

One other tip Nimbus; before mounting the spacer, if you plan on having an opening for chaff ejection, pay close attention to the direction of your TO fan.  Some go clockwise, others counterclockwise, sorta like people in general.   

[J.Jirehs Roaster]

That sounds like a long time under 300F in the drying phase, Wild Bill.

One other tip Nimbus; before mounting the spacer, if you plan on having an opening for chaff ejection, pay close attention to the direction of your TO fan.  Some go clockwise, others counterclockwise, sorta like people in general.   

its my current profile based on the info here... no ill effects so far

[nimbus]

Ok...got it all done. Heater disconnected, spacer fabricated/installed. I've done a couple roasts on it. No hitches thus far.

One thing - strange ...the rotating arm on the stir crazy stops every now and then and changes direction of rotation. Would not have expected that. Is this normal?

My first cracks have been around 11 minutes, second cracks 15 min or so. So that seems good. Temp in the 400-450 range on the SC. Using 350 grams or so. Using some OLD monsooned malabar I had sitting around, so not primo quality for drip coffee, but coming out ok so far.

Talk to ya'll soon..thanks for the pointers.

[Tex]

Ok...got it all done. Heater disconnected, spacer fabricated/installed. I've done a couple roasts on it. No hitches thus far.

One thing - strange ...the rotating arm on the stir crazy stops every now and then and changes direction of rotation. Would not have expected that. Is this normal?

My first cracks have been around 11 minutes, second cracks 15 min or so. So that seems good. Temp in the 400-450 range on the SC. Using 350 grams or so. Using some OLD monsooned malabar I had sitting around, so not primo quality for drip coffee, but coming out ok so far.

Talk to ya'll soon..thanks for the pointers.

It's normal. One thing I did after my friend David Mankin suggested it - I slit a piece of silicone tubing and slipped it over the top edge of the riser. Now the TO stays in one spot and I don't have to be too concerned about it hitting the floor.

A typical 300 - 350 gram batch takes 12 - 15 minutes, depending on the TO power level.

[JHan816]

Hello everyone!

This is my first post and have been lurking about two months reading all the great information here. I have recently built a SC/TO and am learning how to use it. I saw Peter's SC/TO setup and web page and I am using his version of the spacer ring with the wooden clip to open for chaff -- it works great!

 I was thinking of building a similar cabinet to Peter's but on a smaller scale (only 1 SC/TO). My question is what he has above the roasters in the cabinet. A range hood inside the cabinets or just a 6" opening with a boost fan?  I am thinking with the heat and smoke that you may have metal above your ovens.

I am out in my unheated garage on a rolling cart but will have to move in the cellar for the winter so I will need a vent system. A kitchen range hood to a metal dryer vent might work but is 4". I am hoping it would carry most of the smoke out.

Thanks,
Jack

[peter]

Hi Jack, and welcome!

I'm more than happy to answer questions.

My whole setup is all wood and MDF plywood, with cardboard sides.  There's not enough heat to pose any risk, but if i was to do again and had the capability to use sheet metal I would; I've had some glowing chaff pieces come out and start some smoldering in the chaff laying around the roasters.  I let them go just to see what would happen and they never did anything more than smolder, but it would still be smart to use metal.

For a few years I vented directly into the chimney of the house, and so one 6" duct booster was sufficient.  But I had to move the setup to another part of my basement and now I have a 6" duct going through a closet and into my attic, and there is a duct booster fan in the basement pushing up, and one in the attic pulling smoke up.

Even at that plenty of smoke escapes into the basement.  It doesn't matter because there's no one else living here other than my dog, and she doesn't mind.  If you look at my cabinet there are three hinged flaps; two are always down and the flap that's up is in front of the roaster making the smoke.  You may have to experiment with the opening on your cabinet.  I'm thinking if you built it tall and narrow so that you might have a 2' square roasting area, with a 2' square opening, but it would be 4' tall overall, you'd have a 2' "hood" and that might give the smoke a place to congregate while the fan was trying to keep up.  You might think about incorporating a hook of some sort, about a foot directly above the roaster to hang the TO when it's not roasting.

I thought a lot about different fans, and tried a bigger squirrel cage blower, but then went with the duct booster fans because they're readily available and easy to replace, and not so powerful that they're sucking too much air out of my basement.

Hope that helps,

[JHan816]

Peter, thanks for your reply. My garage is unheated but attached, I guess I can see how cold it gets in there and try venting to the garage window. I will still build a stand for the setup.

Thanks,
Jack

[peter]

In the middle of a January cold snap, my basement has gone as low as 46 degrees.  After the first batch the roaster warms up, and it's business as usual.  Another good reason to switch the SC's heating element.

[RobertL]

Today I won a DecoSonic turbo oven on eBay so I have taken the leap in to the SC/TO world. I purchased a stir crazy from Target. So far I have disconnect the heating element and replaced the plastic nut/cap with a wing nut. I couldn't find the aluminum strip I need at Home Depot or a local hardware store I'll try Lowe's tomorrow.  I still need to decide how to modify the stirrer arms, with barrier strips or Peter's modification. I plugged in the SC and it only makes one rotation every five seconds is that normal?

[grinderz]

I found the aluminum strip at lowes. If I recall it was close to the door lock-sets and the key cutting machine.

[JHan816]

Hi Robert,

Lowe's should have the aluminum you need. I bought the 1 1/2" wide X 4 foot strip. Try to get the 1/16" thick stuff, it is easier to bend. I started out with an open ring for chaff removal but switched to Peter's version and I find it helps keep the heat in. The SC speed seems right, I think the motor is 12 rpm.

--Jack

[J.Jirehs Roaster]

5 seconds sounds right..  my vote is for the peter style stir arm.. .   

[peter]

5 seconds sounds right..  my vote is for the peter style stir arm.. .

The reason behind my stirring arm design was to be able to do small batches w/o the 'angel wings' effect.  You can use the stock stirring arm, which works fine, it just depends on the batch size.  The reason for the barrier strip mod is only if you want to increase batch size, but then you won't get good agitation on smaller batches.  I don't know what range the stock arm is good for, maybe 6-10oz., so if you're good w/ that I'd say leave it alone.

I really like my stirring arms because I roast a lot of samples, and can go as small as 100g.  But the design is a real nightmare to bend and keep everything in a plane so it doesn't scrape.  It might make sense to consider two different arms and just switch them out depending on batch size, since it's only one wing nut.

Lowes is where I found my strips.

[RobertL]

Thanks for all the replies I'll head over to Lowe's for the aluminum strip today. Peter your idea about multiple stir arms sounds good to me. Okay so I have read all of this thread but I still have a few questions. Should I attach the aluminum with screws and use the high temp rtv to seal it? Will this thermometer work for BT or would I need to upgrade the probe to something metal?

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