Stuck Mash

[redbeard]

I used my new 45l esky & new pvc manifold on the weekend. i did a batch sparge but had a very slow / stuck mashout. i underletted with some sparge water, which helped a bit, but ended up just letting it slowly runout. i also noticed the manifold was inclined to float a bit, indicating some air still inside.

the grain was milled by esb & was 4k pale malt with 0.5kg wheat & 0.1 crystal. when cleaning up, i checked the manifold & it seemed to be gummed up with fine particles (see pic).

from searching the archives:
1. put a couple of litres of water in 1st, then drain some off to purge air in manifold
2. when 1st runnings, open valve half way and increase after a few litres
3. use a grainbag over manifold.

would enlarging the slits in manifold help ?

any other suggestions / comments ?

cheers

 

[Sean]

Are the slits in the top of the manifold? If it's trying to float, is it bending and (partially) closing the slits up ?

 

[Gough]

G'day Redbeard,

The slits do look pretty skinny, but I reckon trying the slightly slower drain to start you first runnings before opening it up a little more (point 2. on your list) will help a fair bit. You also will have a pretty shallow grain bed with only 4.6kg malt in a 45 litre esky which may be affecting things. Try it again starting your first drain a little slower with or without the grainbag and if it is still happening you could widen the slots a little. I have a 47 litre esky and use a copper manifold with thinner tubing and 4 parallel lengths rather than the 2 you have there (so similar enough I guess) and I find using the slower first 2 recirc drains before opening it up full throttle does the trick. Only had 1 stuck sparge and that was with a shallow grain bed and a full throttle first drain. Changed my technique and haven't had that problem since.

Good luck ,

Shawn.

 

[Linz]

Personally I would get a small drill bit(1/8 or smaller) and drill 2 holes tween every slit(LEAVE IT ALONE). This will mean more recirculation but worth the run off.

 

[redbeard]

Are the slits in the top of the manifold? If it's trying to float, is it bending and (partially) closing the slits up ?

[post="69511"][/post]​

the slits are on the bottom. i did notice one of the far corners floating. i guess using the tubing to connect the manifold to the all thread allows more flexibility than perhaps needed. the pipe is 15mm and i think you would need a lot of pressure to twist the pipe to close the slots.

 

[redbeard]

Personally I would get a small drill bit(1/8 or smaller) and drill 2 holes tween every slit(LEAVE IT ALONE). This will mean more recirculation but worth the run off.

[post="69529"][/post]​

if looking at a cross section of the pipe, the slits are on the bottom, hence go from 3 to 9 on a clock face. do you mean put holes at 3 & 9 or at 6 ?

thanks

 

[redbeard]

You also will have a pretty shallow grain bed with only 4.6kg malt in a 45 litre esky which may be affecting things. Try it again starting your first drain a little slower

I have a 47 litre esky and use a copper manifold with thinner tubing and 4 parallel lengths rather than the 2 you have there

[post="69516"][/post]​

yeah, i guess i didnt realise how shallow the grainbed would be with a 45l. palmer recommends 4" minimum, which i think was close to what i had. i had planned to have 3 parallel lengths but couldnt find any 15mm pvc cross pieces.

will try starting very slow.

cheers

 

[Linz]

Personally I would get a small drill bit(1/8 or smaller) and drill 2 holes tween every slit(LEAVE IT ALONE). This will mean more recirculation but worth the run off.

[post="69529"][/post]​

if looking at a cross section of the pipe, the slits are on the bottom, hence go from 3 to 9 on a clock face. do you mean put holes at 3 & 9 or at 6 ?

thanks

[post="69535"][/post]​

Holes at 5 and 7 or a tad closer together if possible. comprende?

 

[redbeard]

Holes at 5 and 7 or a tad closer together if possible. comprende?

[post="69698"][/post]​

yes, thanks

will try again this weekend ...

 

[shmick]

Are the slits in the top of the manifold? If it's trying to float, is it bending and (partially) closing the slits up ?

[post="69511"][/post]​

the slits are on the bottom. i did notice one of the far corners floating. i guess using the tubing to connect the manifold to the all thread allows more flexibility than perhaps needed. the pipe is 15mm and i think you would need a lot of pressure to twist the pipe to close the slots.

[post="69534"][/post]​

You could try drilling a few small holes in the top of the tubing.
Should let out any trapped air & help reduce it floating.

 

[Troob]

I think the slits are too small.

At the full mash demo at the 'Monk last Saturday the students had to construct a braided hose manifold. Run off was so clear no need to recirculate but was very slow. Tom is gonna have a much longer manifold for the lesson on thje 27th of this month



Troob

 

[Tony M]

Looking at your foto, you have space enough to double up on your slits and they could be wider. The first false bottom I made had 4mm dia. holes in it and though I had to recirculate 4 or 5 litres to run clear, once at this stage I got a good clean wort.

 

[Linz]

Another quicker fix would be to put 2, mebbe 3 blades on your hacksaw and go thru the slits again

 

[warrenlw63]

Redbeard.

The underlying problem with PVC is if you try and open the holes up more there's a real chance you'll crack or split the pipe due to the slots being so close together.

This suggestion may sound somewhat daunting. However if you go and buy some copper pipe and do exactly the same thing you'll have a manifold that's more durable with less chance of floating in the mash. I'm pretty certain you can even get away with not soldering it.

Sounds a pain. However if you're going to be mashing for any length of time it's a job worth doing right.

Another alternative if you want to persist with the PVC would be to buy one of those Dremel knockoffs that Supa Cheap Auto is selling for around $30. They come with a number of cutting discs/wheels that can easily open the slots up a little. The tool will come in handy for several other brewing-related projects too.

Mine's had quite a workout already.

Warren -

 

[Borret]

Redbeard.

The underlying problem with PVC is if you try and open the holes up more there's a real chance you'll crack or split the pipe due to the slots being so close together.

This suggestion may sound somewhat daunting. However if you go and buy some copper pipe and do exactly the same thing you'll have a manifold that's more durable with less chance of floating in the mash. I'm pretty certain you can even get away with not soldering it.

Sounds a pain. However if you're going to be mashing for any length of time it's a job worth doing right.

Another alternative if you want to persist with the PVC would be to buy one of those Dremel knockoffs that Supa Cheap Auto is selling for around $30. They come with a number of cutting discs/wheels that can easily open the slots up a little. The tool will come in handy for several other brewing-related projects too.

Mine's had quite a workout already.

Warren -

[post="69841"][/post]​

Now that we are looking at all crazy options to save the pvc pipe whales here is my 2c..

Yep the double hacksaw blade theory will work but as warren said it may crack. But if we visit some saw blade technology and even windscreen repair technology and investigate the theory of bluntening, then we can get away cheaper than the 30 dollar OZITO purchase. (besides due to the size of the blades on the ozito/dremel and the proximity and depth of the cuts, in the end they will end up on an angle and due to the fact that these things run at a minimum of 10,000 rpm you will end up with a heap of melted sludge on the inside of the pipe that you then must remove)
any way back to bluntening. Take a drill that is slightly larger than what width your slots will end up and drill the absolute end points. This removes any focus point for the pipe to crack from and you should be able to safely to but carefully put 2 saw blades back through it side by side.
Just giving you options, not opinions

Borret :blink:

 

[warrenlw63]

Borretus-killjoy-itis

Ozito/Dremel and their derivatives rotary tools are a good excuse to get a grant from the Minister of Finance/Silly Walks and Parrot Sketches for a cool tool that will serve you for a number jobs.

None of them are household. :lol:

Do you really think the cutting wheels will melt PVC? Hmmm... This never occured to me. Still think copper is a safer/better bet for a manifold.

Warren -

 

[Gough]

Copper is what we use in the Peoples Brewery comrade It is authorised from the very top!

Shawn

 

[warrenlw63]

Yet a scarce commodity. You proletariats have been chopping fingers and unmentionables off the statues of our most-esteemed leaders and visionaries again.

Warren -

 

[Borret]

Mr Warrenskinintikus,

Fear not. The dremel is in my portfolio under most usefull of tools. However many years of modelmaking has taught me that it has it's place and sometimes there are better tools for the job.
Unless one has obtained a blade that resembles a miniature circular saw and not the friction cutting disks that come with these tools as standard, then you will be infact be melting the plastic rather than cutting it. Which means it sticks to the back of the cut in it's molten state. One gripe I have is also is that the bottom speed of 10,000rpm is what causes this and that they don't have enough torque to work with the diameter of a disk at these speeds anyway.

My biggest issue with the dremel- It Has MADE IN MEXICO written on it! :lol: :lol:

Long live the people's breweryhurrah, hurrah! :beerbang:

Borret

 

[ozbrewer]

Borretus-killjoy-itis

Ozito/Dremel and their derivatives rotary tools are a good excuse to get a grant from the Minister of Finance/Silly Walks and Parrot Sketches for a cool tool that will serve you for a number jobs.

None of them are household. :lol:


Warren -

[post="69848"][/post]​

ok guys, im gonna share a secret with you all, but it cant get out, it will ruin MAN kind for eternity......

1.It goes like this, SWMBO comes to you with yet another silly job around the house, broken handle on a saucepan, broken light bulb....dead lamp...what ever.

2.take the offending item to the shed

3. Have a 6 pack

4. come back an hour later and say the only way to fix it is a to get a dremmel so you can shave the build up of carbondicloicoxyacid off the offending item, thus making it work for ever.

5. go to Bunnings and get a dremmel

6. go back to shed, spend 5 mins fixing the item that probably wasnt broken, or re attatch the wire that you took off (good vith her favorite hair dryer?)

7. spend the next few hours playing with your new tool

8. take the fixed item back to SWMBO, and enjoy the rewards she offers you