New (Old) Oven for Curing
#14
(01-09-2019, 11:18 PM)Roly Wrote: If you pull a vacuum while heating, water will boil off at a much lower temperature.   Probably quicker also. If you have a sensitive vacuum gauge you can see where  the vacuum drops off when the water has been boiled off.  Roly

Thanks Roly.  Hey that is interesting...so for drying wood (before Juicing it)--drawing the vacuum would speed up that process AND most likely improve the removal of moisture from the blanks.  Been 45 years since high school science, i'd forgotten that.  And in the drying phase drawing a vacuum should not have any impact on the material being dried being able to later absorb CJ.  

I still think that for curing after soak that drawing a vacuum may be counterproductive since the goal is polymerization of the liquid, not removing it, but i'll probably experiment at some point with some scraps as it may create some subtle effects.

earl
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#15
Finally got my valves and hoses set up last night and got some real testing done. Pulled 29" with less than 4 minutes of pump time. After 5 hours, was at 27", 10 hours 23.5", and 12 hours at 22". So, the seal isn't 100%, but not too bad on a few minutes of pump time. Took well under 2 minutes to run back up to 29" a bit ago and still there an hour later. When i ran it back up, i was able to do so without losing any ground. Will see where we are over the next few hours.

For drying wood to stabilize, that's plenty of vacuum since the vac is a bonus. For stabilizing--being able to stay at not less than 27" for 5 hours seems like it should be plenty to get good penetration. Next up will be drying a batch and trying a test batch to stabilize. Been looking around the kitchen, and the size of the oven chamber really opens up the number of clear plastic containers that can be adapted for small batch stabilizing--even if only for a single batch. A lot of recyclables may see a batch of CJ before they leave the house!!
earl
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#16
(01-12-2019, 11:32 AM)greenacres2 Wrote: Finally got my valves and hoses set up last night and got some real testing done.  Pulled 29" with less than 4 minutes of pump time.  After 5 hours, was at 27", 10 hours 23.5", and 12 hours at 22".  So, the seal isn't 100%, but not too bad on a few minutes of pump time.  Took well under 2 minutes to run back up to 29" a bit ago and still there an hour later.  When i ran it back up, i was able to do so without losing any ground.  Will see where we are over the next few hours.

For drying wood to stabilize, that's plenty of vacuum since the vac is a bonus.  For stabilizing--being able to stay at not less than 27" for 5 hours seems like it should be plenty to get good penetration.  Next up will be drying a batch and trying a test batch to stabilize.  Been looking around the kitchen, and the size of the oven chamber really opens up the number of clear plastic containers that can be adapted for small batch stabilizing--even if only for a single batch.  A lot of recyclables may see a batch of CJ before they leave the house!!
earl

You will appear to lose vacuum but if there is moisture boiling off, this change from a liquid to a gas will cause a loss of vacuum.   If the test was done without any wood inside it and was at a constant temperature, then it is a vacuum leak. @ 29" of vacuum, water will boil @ 76 degrees F.  @ 27" of vacuum it will boil around 112 F.   Roly
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