Another KKTO on the cheap

[russellb]

Re: Another KKTO on the cheap

OK, measured, and by that calculation + 1 litre for the oven head, would be 9.4 litres.

Russell

[Koffee_Kosmo]

Re: Another KKTO on the cheap

OK, measured, and by that calculation + 1 litre for the oven head, would be 9.4 litres.

Russell

Thats OK and in the ball park Russell

It may just be that you need practice :

KK

[russellb]

Re: Another KKTO on the cheap

Thanks again KK

Looking at your video of the agitator, which comes up on youtube, I wonder if I should slow the mixing speed, rather than speeding it up. I can see a session playing with a load of green beans to see how it goes.

Russell

[Koffee_Kosmo]

Re: Another KKTO on the cheap

Thanks again KK

Looking at your video of the agitator, which comes up on youtube, I wonder if I should slow the mixing speed, rather than speeding it up. I can see a session playing with a load of green beans to see how it goes.

Russell

I have found that 65 to 75 RPM is ideal
Put a stop watch on it

KK

[WSullivan]

Re: Another KKTO on the cheap

I was going to say something about the speed of the rotation, but forgot, i know KK has done a lot of experimenting with RPMs, he found 70 RPM to be best......for his roaster, my window winder motor rotates at 70 RPM too, lucky me

[russellb]

Re: Another KKTO on the cheap

OK, I have had a play with some green beans and varying speed.

[media]http://www.youtube.com/watch?v=q1nq95dlAog[/media]

Starting as I had left it last time with a loaded speed of about 72 RPM (unloaded 81 RPM), then 60 RPM and finally 30 RPM.  I used a halogen lamp to give plenty of light, and set "shutter" speed at 1/1000 sec to improve the quality of the images.

I would value the comments of the more experienced as to which looks to give the best mixing. I have been a bit reluctant to run too slowly, lest I overheat the motor, but after a bit of playing around today, it seemed cool enough. Hopefully the low load means that not too much heat needs  to be dissipated.  Ill keep an eye on it next time I roast.

Looking at the video slowed down, I think there may be a layer around the outside of the beans which is rotating, but not mixing well. I may try bending the vertical struts of the agitator out to encourage these to move inwards, though  I did have problems with beans jamming against the metal if I went too close to the pot earlier.

Russell

[WSullivan]

Re: Another KKTO on the cheap

Personally i think with your agitator 60 RPM look like its moving and folding the beans the best, 70 looks to fast and 30 sounds like the motor is screaming for more power, i noticed that beans are getting pushed back toward the centre better at 60 RPM but i think the agitator still needs some mods, i love the design and ill be copying it tomorrow ;D but if you could bend one of those blades to try and bring the beans on the outer circumference to the inside then push them out again with the other side.

Have you tried the coloured bean with this? Id drop one on the outside ring of "non mixing" beans to see how long it hangs there for......

cheers

Im off to bunnings in the morning to go shopping!

PS where did you get that SS from?

warren

[russellb]

Re: Another KKTO on the cheap

Thanks for the comments, Warren,

Ive had a bit of a go and I think I[ll have to extend the vertical bars. Bending them outward makes them too short. I guess I could shorten the drive shaft a little as an alternative.

I dont recall where I got the SS, Ive had it for many years in the stock collection. There is a local metal seller who would probably have some, but not helpful for you.

Regards

Russell

[Dimal]

Re: Another KKTO on the cheap

Gday Russell....

Heres a brief video clip of a commercial roaster just before and during the bean cooling process....

[media]http://www.youtube.com/watch?v=D7pm_qovD_Y[/media]

Gives you a good idea of how the design thoroughly works the beans to ensure efficient and even cooling. The same would hold true in a KKTO for heating the beans as its just about heat transfer in as efficient a manner as possible.... 8-)

Cheers,
Mal.

[Koffee_Kosmo]

Re: Another KKTO on the cheap

As I said above
Speed & good mixing go hand in hand

Test again with a coloured bean
Bend the blades as required to achieve a good all round mixing result

60 RPM looks about right
KK

[russellb]

Re: Another KKTO on the cheap

Well, Ive spent a large part of the last couple of days trying to modify my agitator, and at least a couple of coloured beans will move from the outside or from the centre in about 4-5 revs of the agitator. However I ran a couple of 300 gram roasts, and they still seem rather unevenly browned.

Ive got another been variety also, so Ill give that a try, but I may well redesign the agitator. The major design problem has been allowing a suitable gap to prevent beans jamming against the wall. I think arranging it so that the blades trail as they go near the wall. Ill have to get more SS if I redo it.

Anyway, Ill report back after Ive sampled todays cooking.

Russell

[WSullivan]

Re: Another KKTO on the cheap

Ok Russell, i think ive nailed it! , im at work at the moment so i cant post pics, ill post some pics tmrw, i spent the best part of today building it, its at prototype made out of alloy bar.......dont worry no beans will be consumed out of the test roasts. Ill get some SS when im sure its what im after and make another.

I basically did one loosly based around yours, with a solid square bar across the top, with two hangers that hold teh blades, one is an arrowhead shape and sits right on the deck, it moves the beans from the middle to the inside and outside(of the pot), and the other side of the bar is one to move the beans from the outside to the middle, so basically as it rotates it move beans from the inside and outside to the middle then out again, it works really well with all beans moving perfectly IMHO ;D

Ill post a vid tmrw too

ps i had a major "issue" wtih the probe today, roast halfway to FC, jammed agitator against the DMM probe! thats tomorrows job!

cheers
warren

[russellb]

Re: Another KKTO on the cheap

One of the things that led me to this design was to put the thermocouple probe in from the bottom. Ive had the agitator hit the probe ,but now check its not in the path with every change I make.

I look forward to seeing your interpretation.

Regards

Russell

[Mono]

Re: Another KKTO on the cheap

I basically did one loosly based around yours, with a solid square bar across the top, with two hangers that hold the blades, one is an arrowhead shape and sits right on the deck, it moves the beans from the middle to the inside and outside(of the pot), and the other side of the bar is one to move the beans from the outside to the middle, so basically as it rotates it move beans from the inside and outside to the middle then out again, it works really well with all beans moving perfectly IMHO Grin

Ill post a vid tmrw too Wink

ps i had a major "issue" wtih the probe today, roast halfway to first crack, jammed agitator against the DMM probe! Shocked thats tomorrows job!

cheers
warren

Gday Warren, look forward to the video to see your stroke of ingenuity. I hope to receive my "beta" kit from KK today as I have given up building my own in frustration. I will finish the KKTO I have started [eventually] once motivation returns. The jamming agitator is/was going to be the death of me :


Steve.

[WSullivan]

Re: Another KKTO on the cheap

Gday Warren, look forward to the video to see your stroke of ingenuity. I hope to receive my "beta" kit from KK today as I have given up building my own in frustration. I willfinish the KKTO I have started [eventually] once motivation returns. The jamming agitator is/was going to be the death of me Roll Eyes


Steve.

lol steve, i have posted the vids here, best of luck mate, the KK kit is very well engineered so you wont have any more problems....just wonderful roasts!

cheers
warren