From scratch roasters - worklog

Koffee_Kosmo

You can still use gas in the same way the original design uses a halogen lamp Its old school and is called direct flame Here is some info on it and how to build one http://www.homeroasters.org/php/forum/viewthread.php?thread_id=2153 It will set your roaster apart Plus I wouldn't be guiding you down this path if I did not think it would work KK

RichardM

Koffee Kosmo wrote:

You can still use gas in the same way the original design uses a halogen lamp Its old school and is called direct flame Here is some info on it and how to build one http://www.homeroasters.org/php/forum/viewthread.php?thread_id=2153 It will set your roaster apart KK

Indeed, and I'm keeping that option open. I could just get an LPG blowtorch and rig that up. I'm kind of skeptical that it would offer any benefit though, just due to the condensation from the flames inside if the ventilation wasn't high enough. Also, if there weren't enough oxygen for the flame, that could cause some dramas.

Koffee_Kosmo

RichardM wrote:

Indeed, and I'm keeping that option open. I could just get an LPG blowtorch and rig that up. I'm kind of sceptical that it would offer any benefit though, just due to the condensation from the flames inside if the ventilation wasn't high enough. Also, if there weren't enough oxygen for the flame, that could cause some dramas.

Oxygen will feed the flame via a hole outside the roaster, Edit:- on the gas probe/burner itself KK

RichardM

Koffee Kosmo wrote:

Oxygen will feed the flame via a hole outside the roaster

Ah, haven't really done that research. If that's the case, I might pop my head in to BOC Gas and Gear this week and see what my options are. Realistically, it won't change the way I do the build though, and I will be able to change my mind at the last minute if need be.

Koffee_Kosmo

On shift work at the BHP we made our own BBQ's so we could take a steak in on afternoon shift Anyway we just had a piece of pipe with may holes drilled along the top Sealed at one end A gas fitting on the other, also air adjust hole (similar to a Bunsen burner) Worked a treat KK

RichardM

Hmm, so just to make sure we are on the same page, I assume you're talking about something like this: http://www.auscrown.com/page/shop/flypage/product_id/103/a/category/e/blowtorch_blowtorchburners which would be equivalent to around 3kW electric, which should be enough direct heat to roast 1kg of beans (with the added benefit of just changing tips if it wasn't). I saw that guy on homeroasters that you linked using 26kW of heat in the two bowls - I'm amazed he didn't incinerate the bowls. The only thing I'm really concerned about is whether the beans at the back would get enough heat - which I guess comes back to whether I'm trying to heat the air, heating the drum, or heating the beans.... (why oh why didn't I just build a KKTO. That would have been pure simplicity compared to this monster that is taking on a life of its own). Just wanted to say thanks again for the help here. I really do appreciate it - couldn't do it without the community here 🙂

Koffee_Kosmo

You will only know from experiments on the best blow torch tip to use The purist direct flame roasters also had the beans quickly crossing into the flame while tumbling I help in any way that my trade experience allows It matters not what path a fellow roaster takes KK

RichardM

Today's acquisition: 1 x 24V DC 13RPM motor with worm gear Housing from an old "Fiery" - basically a big solid steel box to mount everything on Pedestal from photocopier - will form a sturdy base. No pics today, but this will give me something to work on for a while. What I am having issue with is obtaining reasonably priced metal lids for my 28cm saucepan. They all seem $50+. I might end up having to bite the bullet and just spend the money 🙁 I want something like this: http://www.nisbets.com.au/product.asp?pID=4683&cID=242 but with a flatter handle, and not for the $40 it would end up costing including shipping.

Koffee_Kosmo

Regarding the lid Go to a few second hand stores and you may get lucky Also if you have any African goods stores close by, they will have large pot sets/ lids Also I will have a look to see if I have one from my build of the original KKTO You may be lucky a second time Also 13 rpm may be a little slow KK

WotB

Did you want a glass one? Might try an asian supermarket or junk store.

RichardM

Koffee Kosmo wrote:

Regarding the lid Go to a few second hand stores and you may get lucky Also if you have any African goods stores close by, they will have large pot sets/ lids Also I will have a look to see if I have one from my build of the original KKTO You may be lucky a second time Also 13 rpm may be a little slow KK

13rpm will be too slow, for sure, but I've got a full gear assembly that I can easily change ratios on. Should get it to about 30rpm easily - it's a worm gear drive, so should handle the increased load (it's a toner stirring motor from ...a photocopier). WOTB - I have a glass one - they are a dime a dozen (even got one with the saucepan I bought) but not being able to easily drill into it is just a pain in the neck and makes things too difficult. Regarding lids, I've tried two asian stores, Big W, K Mart, Target, Myer (had them but too $$$), a kitchen catering place, and Vinnies. We have no African stores 🙁 I will have a look at some second hand stores this weekend (going to the sunshine coast, so will have a look there).

shape_shifter

Richard we're watching your progress. Our new roaster is also a start from scratch as we're keeping the smaller one for home use and making the larger one for supplying others so making it hold at least 500 grams 🙂

Gra

RichardM wrote:

Today's acquisition: 1 x 24V DC 13RPM motor with worm gear Housing from an old "Fiery" - basically a big solid steel box to mount everything on Pedestal from photocopier - will form a sturdy base. No pics today, but this will give me something to work on for a while. What I am having issue with is obtaining reasonably priced metal lids for my 28cm saucepan. They all seem $50+. I might end up having to bite the bullet and just spend the money 🙁 I want something like this: http://www.nisbets.com.au/product.asp?pID=4683&cID=242 but with a flatter handle, and not for the $40 it would end up costing including shipping.

How a bout a Pizza Tray Aluminum - 28Cm $6.95 in most kitchen shops.. Cheers Gra.. --------------------------------------------------------------------------------

RichardM

Gra wrote:

How a bout a Pizza Tray Aluminum - 28Cm $6.95 in most kitchen shops.. Cheers Gra.. --------------------------------------------------------------------------------

Indeed, I had thought of that, and cake pans. I got some crazy looks walking around the stores trying to find random different tins/trays that would fit snugly. The lids are always about 4mm smaller than the saucepans (which I believe are actually 285mm, not 280). I even pulled some springform pans apart to see if the "28cm" ones would fit, but they didn't. Thanks for the suggestion though 🙂 If anyone does have any 28cm Pots (pretty standard size) and a heap of random trays, could they please tell me what brand the tray is???

Koffee_Kosmo

OK I have a stainless steel lid Inner dia - 275mm (the bit that fits inside the pot) Outer dia - 298mm ( the outer rim that sits on the rim & overlaps) I will swap you for the glass lid as its currently used for protecting the guts of my original KKTO Also I have 2 smaller lids & pots in the garage These have never been used as I got a pot set of three at the time KK

RichardM

Koffee Kosmo wrote:

OK I have a stainless steel lid Inner dia - 275mm (the bit that fits inside the pot) Outer dia - 298mm ( the outer rim that sits on the rim & overlaps) I will swap you for the glass lid as its currently used for protecting the guts of my original KKTO Also I have 2 smaller lids & pots in the garage These have never been used as I got a pot set of three at the time KK

KK, that would be fantastic. Just PM me your details and I'll PM you mine, and post you the glass one tomorrow. Richard

RichardM

I am very sick of this throw out society we live in. Had some spare time today, so went to dick smith, and jaycar looking for stepper motor drive circuits.....only to find dick smith now sells things like hair straighteners etc, not components, and jaycar didn't have anything like that in stock. It seems people just aren't doing hobby like this anymore. I'll have to make do with the 24V DC motors for now. Also went looking for direct flame sources, only to find between three welding/gas places, I couldn't get a solution for under $400....yet I can get things online very cheaply (meeting aus standards). No wonder people shop online.....

RichardM

Ok, so after a lengthy discussion with a gas fitter my in law knew, I have decided against direct flame, purely because of price. I have obtained a burner to go under the pot today. It's a three ring burner that will put out around 8kW of heat: http://www.bcf.com.au/online-store/products/Primus-Triple-Ring-Burner-RB40.aspx?pid=114492#Description The picture doesn't do it justice, it's VERY weighty and large. The centre burner will just be used as a pilot, with the other two for temp control. I will have a lot of work to do this weekend putting pretty well the whole thing together.

Koffee_Kosmo

A suggestion Heat applied from the outside without a barrier can be wasted I also suggest a cowling/cover for heat retention and safety Doesn't need to hinder the flame ring KK

RichardM

Koffee Kosmo wrote:

A suggestion Heat applied from the outside without a barrier can be wasted I also suggest a cowling/cover for heat retention and safety Doesn't need to hinder the flame ring KK

Indeed. A flame diffuser will be fitted, and I'll put some metal sheeting either side to try and guide the heat up onto the pot. I think if I put 8kW out there, maybe half of it will be wasted (???) so that still should be plenty to roast up to 1kg (as long as the stirring, airflow etc is good of course, which will remain to be seen).