Building a Kaldi type home roaster

Discuss roast levels and profiles for espresso, equipment for roasting coffee.
NicaDon
Supporter ♡

#1: Post by NicaDon »

I have used Fresh Roast roasters, an SR500, 700 and 800 for years. I am now living in India, a 220v country with 50% taxes on imports and will probably have to build my own roaster. I'd like something similar to the Kaldi using a simple mesh drum as seen on eBay and Amazon, usually hand cranked. I can easily have a body fabricated and adapt a drive motor. What power and speed of motor would you recommend that I could use? I can pack the drum in luggage and buy a motor here.
LMWDP #730

Capuchin Monk

#2: Post by Capuchin Monk »

My Kaldi Wide 400 came with 6Watt 24VDC 2950 RPM motor and the gearbox that spins 60 RPM. If this is Kaldi model you are thinking of, then little bit smaller motor may also work.

User avatar
hankua
Supporter ♡

#3: Post by hankua »

Two of the choices people in the USA use for BBQ grill coffee roasters are a 50rpm Dayton parallel shaft gear motor (the one with a plastic fan) and a Wiper style of motor such as the "maker motor" https://makermotor.com/pn01007-38-3-8- ... rmotor-dc . The maker motor style can be found on Ebay along with various types of small gear motors. A Kaldi would use a smaller gear motor than what I've suggested.

The auto wiper motor can be found in junkyards, so it could be sourced in India. The entire roaster should be able to be fabricated in India used local supplies. The type of fan used for coffee roasting is usually heat resistant blower, a computer case fan could be used in a pinch for the tiny application.

NicaDon (original poster)
Supporter ♡

#4: Post by NicaDon (original poster) »

Capuchin Monk wrote:My Kaldi Wide 400 came with 6Watt 24VDC 2950 RPM motor and the gearbox that spins 60 RPM. If this is Kaldi model you are thinking of, then little bit smaller motor may also work.
Yes, that's what I was thinking and wow! it is cheap in Korea! Buying it off eBay and then another $175 or so for import taxes turns it into a $500 machine. While looking for motors on Aliexpress I saw this, prices ranging from $65 to $130 shipped to the US. I bought one for the sake of simplicity and don't think it would be much cheaper to build one. Two months for delivery but I won't pass through LA until February. This, La Pavoni #2 and a 1Zpresso J-Max I just bought here will set me up next year. I've had 2 espressos in 3 months...

https://www.aliexpress.com/item/3256803 ... E1Q70D7LD
LMWDP #730

Capuchin Monk

#5: Post by Capuchin Monk »

I see other listings when I scrolled down that page. :idea:

Milligan

#6: Post by Milligan »

I've seen RC car gear boxes that have multiple speeds and you can change the pinion and spur gear to get the settings you want. You can find the gear boxes in all metal and a variety of cheap brushed motor options. Most use an output shaft that can be adapted to anything. I wonder about a convection oven fan. They are all metal and are made for high temperatures. I bet you can get one very cheaply used. Sounds like an interesting project.

NicaDon (original poster)
Supporter ♡

#7: Post by NicaDon (original poster) »

I received the roaster when transiting the US and am now using it in Nicaragua. It's very small, fitting in the palm of my hand. I hoped to find a small butane camp stove to roast outside but those are not available here. I finally broke down and roasted indoors and am very happy with the results.

A minor annoyance is the jury rigged motor wants to move with the cage and the speed fluctuates a bit with the movement. I wrap the cord a couple turns around a burner grate to keep it steady. A screen fits in the base which radiates heat like a catalyst and burns the chaff falling down. A rotation speed of 30 to 60 rpm works well with first crack at 11 minutes and second at 13:30. I ordered a hollow center shaft and thermocouple kit from another seller for temperature readout, $25 shipped but it hadn't arrived in time. There is little chaff to clean up, a surprise after the amounts generated from a Fresh Roast. My first roast was of 200g which was slightly uneven, subsequent ones 180g with excellent results.

Now I'll sell the SR500, 700 and 800 (I hope, I don't think there is much interest here) and order another of these to take to India on my return. While there I plan to have a simple base made up similar to the Kaldi Mini for heat retention and the motor support. Other vendors sell the hand cranked ones for $50 to $150 and motor kits for $30. The seller I bought this from radically undercut the others and was pleasant to deal with. I feel this little roaster would be a cheap, easy way to check out another method.

http://www.youtube.com/watch?v=52gR4jwLjBw

First roast, 200 grams.
LMWDP #730