I'll get in touch and we can communicate directly to get this sorted. I'm pretty sure that this is not some kind of a huge problem that could not be fixed. I'm sure we'll get to the bottom of it once we compare notes and we'll both be wiser by the end it. :super:
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Mardoo
Noob What Craps On A Bit
Ah, the double-edged sword of social media ;P
Just a quick note to mention that I have been communicating with Michael and we have some ideas as to why I'm seeing a temperature differential. Both of us have been testing and I will do more tests to get to the bottom of this. I am building a little contraption for the probes I'm using to ensure maximum accuracy. So far the most likely explanation for what I am seeing is that the temperature differential is caused by the way that the probe attaches to the vessel. I have a whole bunch of ideas for possible solutions. If the experiments prove that it is the probe attachment method, it'll be time to brainstorm some of these ideas.
I should also mention that I think Yeast Forge is an excellent product. Please do not be discouraged by what you read above. I knew after the first two days of owning a Yeast Forge that this is a device I would not want to be without. Go and buy one right now!
I should also mention that I think Yeast Forge is an excellent product. Please do not be discouraged by what you read above. I knew after the first two days of owning a Yeast Forge that this is a device I would not want to be without. Go and buy one right now!
A quick update...
After a fair bit of testing, I think it's safe to say that there is no problem with the Yeast Forge electronics or firmware when it comes to temperature control. The method of attaching and insulating the probe is the critical factor. While the bubble wrap and rubber band recommendation is as simple as can be, I don't think it works well. The bubble wrap is bulky and obscures the probe, which is making it difficult to determine how well the probe is mounted. The large air gaps in the bubble wrap don't really help with insulation. Using bubble wrap is better than having a bare probe, but there must be better alternatives.
I played with a few:
Two sheets of 3mm thick packing foam glued together, with a channel cut out from one sheet for the probe. The probe is mounted vertically, with the cable entering at the top and the probe cylinder wall is parallel to the vessel wall. The tip of the probe is sitting somewhere near the 1/4 to 1/3 distance from the bottom of the vessel. This worked well, but I noticed that after a day or so, the rubber band holding the foam down caused the foam to deform slightly and the ends were lifting a bit. That was easy to fix, I just used two rubber bands to hold both ends of the foam block in place.
An alternative mounting configuration, with a polystyrene mounting block. It holds the probe perpendicularly, such that the tip of the probe is in contact with the vessel wall and most of the probe body is insulated inside the polystyrene. Polystyrene is messy and difficult to work with, so I would probably not recommend it as the best choice of material. Trying to match the curvature of the polystyrene directly to the vessel shape is a never ending exercise in frustration. :angry:
Both mounting methods have greatly improved the accuracy of the target temperature, resulting in an absolute error of less than 0.5C. That's pretty good!
After a fair bit of testing, I think it's safe to say that there is no problem with the Yeast Forge electronics or firmware when it comes to temperature control. The method of attaching and insulating the probe is the critical factor. While the bubble wrap and rubber band recommendation is as simple as can be, I don't think it works well. The bubble wrap is bulky and obscures the probe, which is making it difficult to determine how well the probe is mounted. The large air gaps in the bubble wrap don't really help with insulation. Using bubble wrap is better than having a bare probe, but there must be better alternatives.
I played with a few:
Two sheets of 3mm thick packing foam glued together, with a channel cut out from one sheet for the probe. The probe is mounted vertically, with the cable entering at the top and the probe cylinder wall is parallel to the vessel wall. The tip of the probe is sitting somewhere near the 1/4 to 1/3 distance from the bottom of the vessel. This worked well, but I noticed that after a day or so, the rubber band holding the foam down caused the foam to deform slightly and the ends were lifting a bit. That was easy to fix, I just used two rubber bands to hold both ends of the foam block in place.
An alternative mounting configuration, with a polystyrene mounting block. It holds the probe perpendicularly, such that the tip of the probe is in contact with the vessel wall and most of the probe body is insulated inside the polystyrene. Polystyrene is messy and difficult to work with, so I would probably not recommend it as the best choice of material. Trying to match the curvature of the polystyrene directly to the vessel shape is a never ending exercise in frustration. :angry:
Both mounting methods have greatly improved the accuracy of the target temperature, resulting in an absolute error of less than 0.5C. That's pretty good!
Yob
Hop to it
Ive got a bit of a simplified method, I use this with all of my probes inside fridges and the yeast forge..
small rectangle of packing foam, the squishy stuff not the rigid type.. wrap in gaffa to make it a little more sturdy but still compressible, cut a small V in which the probe sits so that it sits proud of the tape and is therefore first in contact with the vial/FV, in the case of the YF, the rubber band holds it in firm, in the fridge I wedge it against the fridge wall and the FV..
.
small rectangle of packing foam, the squishy stuff not the rigid type.. wrap in gaffa to make it a little more sturdy but still compressible, cut a small V in which the probe sits so that it sits proud of the tape and is therefore first in contact with the vial/FV, in the case of the YF, the rubber band holds it in firm, in the fridge I wedge it against the fridge wall and the FV..
.
megabyte
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Thanks for all the pics and suggestions!
Mounting the temperature probe is the trickiest part of using the Yeast Forge and the better you pull it off, the more accurate your temperature control will be. I'd love to ship something like Yob's insulating block along with the product and Peteru has provided some great ideas that might make it even better like having a solid backing so that rubber bands can't distort its shape over time.
Peteru has helped out with some useful testing results, he even tested a separate DS18B20 probe I shipped to him to see how they compared (within about half a degree).
When I was in China last year I met some neoprene manufacturers and I think they might be able to whip us up a tidy solution, like a belt with a velcro strap. The neoprene seems to grip the glass well enough not to want to slide up the conical shape and if we started using a small, flat temperature probe it might fit nicely under the belt.
Here's a mock up shown on both a 2L and 5L flask. Anything bigger like a jacket would have troubles fitting different flask sizes I think...
I just don't know if 4mm neoprene is going to insulate as well as a good block of polystyrene though so the belt might just be a fancy rubber band replacement.
Mounting the temperature probe is the trickiest part of using the Yeast Forge and the better you pull it off, the more accurate your temperature control will be. I'd love to ship something like Yob's insulating block along with the product and Peteru has provided some great ideas that might make it even better like having a solid backing so that rubber bands can't distort its shape over time.
Peteru has helped out with some useful testing results, he even tested a separate DS18B20 probe I shipped to him to see how they compared (within about half a degree).
When I was in China last year I met some neoprene manufacturers and I think they might be able to whip us up a tidy solution, like a belt with a velcro strap. The neoprene seems to grip the glass well enough not to want to slide up the conical shape and if we started using a small, flat temperature probe it might fit nicely under the belt.
Here's a mock up shown on both a 2L and 5L flask. Anything bigger like a jacket would have troubles fitting different flask sizes I think...
I just don't know if 4mm neoprene is going to insulate as well as a good block of polystyrene though so the belt might just be a fancy rubber band replacement.
Rocker1986
Well-Known Member
I went with the packing foam that I use on my fermenter for the STC probe, but rather than rubber bands I just taped it to the flask. Having said that, I'm not too worried about what the actual temperature of the starter is as long as it's somewhat near the setting on the YF and warm enough to keep the yeast working...
Agreed on the absolute temperature. We're making a starter here, not a beer, so a couple of degrees here or there will be fine as long as the yeast is healthy.
However, the fluctuations in temperature need to be minimised so that the yeast does not struggle. Good insulation will help here. Insulating the probe will help, but insulating the entire vessel is even better. I have an idea, but it needs testing...
Take a cooler bag and put the Yeast Forge + Vessel into it.
If you position the entire contraption in the corner of the cooler bag, it should be possible to bend one of the corners back to allow the top of the vessel to protrude and "breathe".
There should be enough room in the cooler bag to add cool bricks on a hot day to keep the starter temperatures down. On a cold day, the heater in the Yeast Forge will be able to reach and maintain desired temperature.
Size of vessel is pretty much irrelevant, just about anything will fit. It's low cost, easily obtainable and compact when not needed.
However, the fluctuations in temperature need to be minimised so that the yeast does not struggle. Good insulation will help here. Insulating the probe will help, but insulating the entire vessel is even better. I have an idea, but it needs testing...
Take a cooler bag and put the Yeast Forge + Vessel into it.
If you position the entire contraption in the corner of the cooler bag, it should be possible to bend one of the corners back to allow the top of the vessel to protrude and "breathe".
There should be enough room in the cooler bag to add cool bricks on a hot day to keep the starter temperatures down. On a cold day, the heater in the Yeast Forge will be able to reach and maintain desired temperature.
Size of vessel is pretty much irrelevant, just about anything will fit. It's low cost, easily obtainable and compact when not needed.
Moad
Well-Known Member
Loving my yeast forge, thanks Michael. The blurb on the website is exactly what I have found useful... sticking it in the brewery rather than on the kitchen bench.
Rocker1986
Well-Known Member
Mine still sits on the kitchen bench h34r:
Made a bit of a mess with a 1469 starter last week too, bloody thing up and escaped out of the flask and down the outside. :lol:
h34r:Made a bit of a mess with a 1469 starter last week too, bloody thing up and escaped out of the flask and down the outside. :lol:
Yob
Hop to it
I put paper towel under the flask now.
Had the same thing happen and SWMBO not impressed...
I was though.. Super stoked
Had the same thing happen and SWMBO not impressed...
I was though.. Super stoked
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