Thinking of trying RIMS

[bigvalen]

I've a Hop & Grape insulated mash tun, and it's decent, but...I've an eye on something better. I have a 20 litre stainless pot (thin wall) that I think I could put a RIMS kit onto.

All I need is http://www.aliexpress.com/store/product/RIMS-Tube-Assembly-1-5-Tri-Clover-stainless-steel-304/1017341_1564101861.html and http://www.amazon.co.uk/Camco-Screw-In-Element-02923/dp/B0002YUDSI/ref=sr_1_fkmr0_1 right ?

Then wrap the mash tun in some ... insulation of some sort, to keep the cost down ? Oh. How do you drain from it ? I assume a perforated bottom + steel tap isn't going to be enough...

[nigel_c]

You'll need a decent pump as well.

[DEMPSEY]

Probably one of the biggest issues that come up is the flow rate of the wort as it leaves the mash tun and passes through your rims pot. your ability to draw the liquid from the mash fast enough to make a difference without compacting the mash bed.

[bigvalen]

Ah. Pump. Yes. How does one evaluate pumps?

[Hop Bomb]

that ali express brew shop is amazing. Has anyone bought anything from them? Is it all shite I wonder? Leaky disconnects etc? Looks too good to be true price wise

[nigel_c]

How none of us has stumbled across them before I'll never know. Their stuff looks great.

[molc]

Well it's us, so shipping will cost quite a bit unless you an internal company mail. Also Yom get stung on import duties.

[bigvalen]

No, AliExpress is China-based. It's the same as AliBaba, for companies who don't mind dealing in small quantities. It's where most of the US-based homebrew shops get there kit from.

But yeah, 12 litre cornies for 60 quid, seems decent too. Though you do have to contact them in advance for combined shipping.

[armedcor]

I was going to order all my keggle and mash tun fittings from there. I found him a few months back but I've been saving up.
I'm gonna try one of his Grain mills as well.

[bigvalen]

Heh. Also, seems the "solar" pumps are just rebadged ones by this guy; http://www.aliexpress.com/item/Easy-Connect-Water-Circulation-Pump-Food-Grade-Hom-Brewing-Pump-DC12V/1905630428.html

[Quiet_Man]

Have a look at MrDrankins shiny herms setup on the Belfast group page.

[Qs]

that ali express brew shop is amazing. Has anyone bought anything from them? Is it all shite I wonder? Leaky disconnects etc? Looks too good to be true price wise

I got a bazooka screen off them. Its grand but took ages to come. I'd use them again but expect over a months wait for the gear.

[biertourist]

Getting RIMS right when building it yourself is a tricky proposition...

Factors that have to be balanced (some of these are just general recirculation mash considerations, some are specific to RIMS):

• False bottom open area- you need a large surface area when recirculating to avoid getting a stuck mash; you're balancing the flow rate vs. the surface area.  False bottoms with a large % open area are probably the way to go.
• Maximum temperature exiting the RIMS tube vs. rate-of-mash temp increase- You CAN obviously heat the wort to near boiling temps as it exits the RIMS tube (depending upon the heat output and flow rate) but you'll be VERY quickly denaturing your enzymes as they pass through the RIMS tube, the liquid does get returned to the main mash where it will cool down rather quickly, but you still need to control this.  If your wort is reaching mash-out temps or higher on the exit of the RIMS tube, you ARE denaturing enzymes at least a bit.   -If you brew primarily with low diastatic power English base malts, then you need to be more concerned about this.
• Engineering required to balance the 2 previous concerns- if you don't have a large enough surface area in your mash filtration system you'll have to decrease the rate of flow so avoid a stuck mash, that will end up increasing the heat coming out of the end of the RIMS tube unless you can actually control the heat output of the RIMS tube (PID controller is normally the solution here).
• Rate of temp increase- Again, you don't want the output temp of the RIMS tube to be too crazy high and if you have a mashtun that loses a lot of heat, you'll need more heat so that you can raise the temps fast enough.  -If you can't get through those mash temps fast enough the enzymes that you're TRYING to denature will continue working and you'll lose controls which is the purpose of HERMS/RIMS in the first place.  -An insulated mashtun definitely helps here; RIMS certainly have enough power to step mash even with an uninsulated mash tun, but it's harder with smaller batches and you end up raising the temps and possibly having to worry about denaturing enzymes.
• SAFETY- How do you prevent yourself or someone else form getting burnt by the RIMS tube / it burning anything it touches?  -What electrical safety measures do you build it to prevent yourself from getting electrocuted?  How do you ensure that a failure doesn't result in the RIMS tube turning into a huge pipe bomb? -Placing the RIMS below the mash tun and angling it so that it defaults to being full of liquid if a pump fails helps there.
• Cleaning- plan for it; it sucks.

Also remember that recirculation mashing will result in faster conversion so drop your typical conversion times by 15 minutes and start doing the "iodine test" on your first several recirculation mashes to get a handle on the new conversion times. (Track the Diastatic power of the mash and the time required for conversion while recirculating.)

Will your system and your beers benefit from RIMS?  -Many/ most beers don't require multiple step mashing; if you're really into Wheat Beers then that completely makes sense as they can pretty much all benefit from multple steps; if you want to control fermentability closely there's a benefit but you can also control fermentability through mash length and it doesn't require any extra equipment.


RIMS is "cool" but there's almost thing that can add more complexity or "pain" to your brew day and it certainly can result in worse beer (constant recirculation can extract many things that you actually want to leave in the malt in the first place).  -Having the OPTION to recirculation mash is nice, though especially when brewing a wheat beer or when trying to get a really dry beer (West Coast IPA). 

-I am a huge fan of HERMS mashing, mostly because if you already have an electric brewery and a PID controller you can just reuse an immersion or counterflow chiller to enable you to do temp-stepped recirculation mashes on the few beers that can actually benefit from it, without having extra equipment.


Adam

[Damien M]

Great  explainer article Adam! I've always though I wanted a RIMS or HERMS system.... but do I need one... probably not! I still want one, but now will get it for the right reasons! 

[bigvalen]

Thanks Adam. If anything, I'm OK with not trying RIMS for a while yet :-)