Diy S/s False Bottom (square)

[davewaldo]

Hi Everyone,

I thought I'd show off my handy work and check to see what the wise brewers think of my design. I've always liked the 38L coleman beverage coolers as they seem more robust and have thicker insulation than the round type beverage coolers. They also have a nice design at the floor of the cooler so that you can get every last bit of liquid from them. The downside of course is that you can't buy an off the shelf false bottom.

Well I found this guy on ebay who was willing to ship me a 35cm square piece of perforated stainless (only $15 delivered) so I could make my own. The sheets are 304 stainless and have 2mm holes.

Basically I have bent the sheet into an arch so it will support the weight of the grain and then cut it to be a close fit. My plan is to cut a slit in a length of silicone hose to use around the edge of the falsie to create a nice tight seal to stop grain and also to protect the tun from scratches.

I've also added a sprung ring pull (also stainless $7.50 from boat shop) to make inserting and removing of the false bottom easy, without having a handle to get in the way when stirring.

I'm just waiting for my beerbelly bulkhead to use underneath and then it should be ready for a test. All in all the false bottom with silicone hose seal has cost $34.50, the cooler was a bargain off ebay, and the most expensive parts were the bulkhead and ball valve

Does anyone see any problems with this design?

Cheers,

Dave.

Heres some pics.

 

[Sammus]

Looks pretty shmick. If you plan on fly sparging you might want to cut it smaller (like 4cm or so from the edges of the esky), otherwise you can get channeling down the sidewalls. If only plan to batch sparge I'd imagine what youve done would work great.

If you were to cut it down it would be even more work because without it being snug like that it could move around and stuff during the mash which would be a pita, so you have to fix it in place some how...

 

[LethalCorpse]

Are the rivets also stainless? If not, they're likely to rust.

 

[davewaldo]

Thanks Sammus

hmmm good point, I have been trying to make something which would be good for fly sparging if I ever decide to go down that path.

Rather than cutting it down though, I could just fill or cover up the holes for 4cms around the edge... Perhaps have another piece of thin stainless which sat on top and covered the outer perimeter.... Would that work just the same? That way it would still stay firmly in place...

 

[davewaldo]

Are the rivets also stainless? If not, they're likely to rust.

Everything is stainless, my local marine shop was great for inexpensive 316 stainless fittings and screws.

 

[matti]

I agree with Sammus.

My initial false bottom was cut to size of esky tun and promoted, though it was circular, channelling.
If you batch sparge you may not notice the difference until late in second running.
Ideally you would like it an inch from sides and edge of falsy flush to bottom all around.

Matti

 

[Steve]

Looks great! Looking forward to the results..... its the same mash tun as mine.
Cheers
Steve

 

[davewaldo]

I agree with Sammus.

My initial false bottom was cut to size of esky tun and promoted, though it was circular, channelling.
If you batch sparge you may not notice the difference until late in second running.
Ideally you would like it an inch from sides and edge of falsy flush to bottom all around.

Matti

How about this....

I could quite easily make a silicone or stainless bib which would create a 1-2 inch perimeter to cover the holes nearest the edge. The Silicone hose I am planning will cover almost 2cm of the edge holes, then the bib could extend a little beyond this.

Looks great! Looking forward to the results..... its the same mash tun as mine.
Cheers
Steve

Thanks Steve, have you built a manifold for yours or some other invention? How do you find it works?

Dave.

 

[chappo1970]

Looks great Dave! Hugely impressed with your handy work :icon_cheers: . Silicon gasket around the perimeter would be the go IMO.

I would give it a couple of runs first before even considering cutting it down. I wouldn't think chaneling will be a huge issue for you ATM. Can't wait to see it in action!

Chap Chap

 

[razz]

Nice job Dave. Are you confident that the mesh will retain its shape under the mash?

 

[Sammus]

sounds like not a bad idea dave, you'd want a good seal from the silicone tubing though else itll channel around there.

Another good point is made by razz.

 

[LethalCorpse]

Everything is stainless, my local marine shop was great for inexpensive 316 stainless fittings and screws.

Ah cool, didn't zoom the image first time around and it looked like rivets. Valve and bulkhead both SS as well? Marine shops can be pricey for those, but you can get them from geordi or T&S prety cheap.

If the weight of the grain becomes a problem, you might be able to solve it by just using longer screws. The ends of the screws then make a standoff on the bottom of the tun. You could also just add one large bolt through the middle of the ringpull to do the same job. Maybe some silicone stoppers on the ends to stop the bolts from scratching the bottom of the tun.

Overall, great job!

 

[beerbrewer76543]

You're going to put retailers out of business with this DIY action h34r:

 

[ausdb]

Nice job Dave. Are you confident that the mesh will retain its shape under the mash?

Just make a few standoffs up out of pvc tubing offcuts to support the sheet, cut some notches in the bottom to allow the wort to drain out of them middle of them. Or maybe some stainless steel egg rings from the kitchen shop?

 

[razz]

Egg rings ! Top idea ausdb.
Dave, if you have a swiss voile bag you could use that on top of the mesh to stop grain sneaking through.

 

[davewaldo]

Thanks everyone!

Chappo, we'll have to have a brew day soon!

Lethal corpse, I got the bulkhead and ball valve from Beerbelly As well as a spiral burner and medium reg :super:

Thankyou everyone for the suggestions.

I'm quite confident it will hold its shape. It has a lot more of an arch than it looks like, and because it is tight up against the sides it can't push out. But if it does become a problem I was planning on making little support pieces out of left over perforated sheet.

I'll let everyone know how it goes soon!

 

[davewaldo]

Here it is with the silicone hose to create a tight seal around the outside.

It fills any gaps nicely and there is no way any grain will be creeping around the edge. It does stick up a bit in the corners, but its still making a good seal. I could cut little sections out in the corners but I fear this would then lead to it splitting with repeated use. Unless anyone else has any suggestions?

I've found a person on ebay who sells silicone sheets, so if I decide to fly sparge I can easily create a 1-2 inch "bib" to go around the perimeter and tuck under the hose.

I'll be using this setup for a brew on the weekend (assuming my bulkhead and ball valve arrive by then) to give it a good test run. If it performs well I'll be doing my first double batch soon! :beerbang:

Cheers,

Dave

 

[matti]

Great work!
Hopefully we will hear a great report back on how it went, yeah?

Matti

 

[davewaldo]

Hi Everyone!

Just a quick update... I did my first brew with my new mashtun on the weekend. It was also my first double batch, and the first time using my new spiral burner.

WOW, what a great day. Everything went extremely smoothly. My DIY falsie performed very well and allowed very good flow of wort. It did seem to let through quite a bit of fine material but perhaps I need to recirculate more. When all was finished and I emptied the tun there was nothing remaining underneath so obviously there was no grain leaks around the sides. Also, it handled 12kg of grain quite happily.

And what a difference a good burner makes! I've been trying to brew single batches with a 3 ring burner and normal reg and its been a real struggle, time consuming too! But the spiral burner and medium reg was a dream to use. We were up to boil in less than 10 mins and I only had the burner on 60% I reckon. And to keep 50+ litres boiling took a surprisingly small flame. All up I used about 1.6kg of gas for the 60min boil and heating 30L of sparge water. Its almost silent too

Overall I'm really happy with the setup. All I need now is a good cooler for double batches as my immersion chiller isn't up to the volume.

Here is a pic just coming up to the boil.

Dave.

(edit - actually I just looked at the pic... this is soon after the boil started... notice the remains of my first ever boil over YAY! now I really feel like an AGer!)