Across International

[icdog]

How long does it take you guys to purge to shatter an ounce in the AI? Not extract, just purge.

 

[Kcar]

moisture?

I think so. I'm thinking the filter-dryer was saturated
by the second run...

 

[RegisPhilburn1]

How long does it take you guys to purge to shatter an ounce in the AI? Not extract, just purge.

About 8-12 hrs at 110-115 depending on slab thickness, strain, etc. I don't run the vac the whole time though , also don't forget to flip

Also gotta give AI customer services thumbs up, they are sending me a new controller to replace the old as well.

I have a couple AI 1.9's and still have a 5-7f difference between the back right and front left corners, even with marble shelves. Anybody have a solution for this? The hydrion sales rep told me their ovens heat from all 5 sides, can anybody attest to this?

 

[icdog]

8 - 12 hours in the actual oven? and at vac?

 

[Hash Man]

About 8-12 hrs at 110-115 depending on slab thickness, strain, etc. I don't run the vac the whole time though , also don't forget to flip

Also gotta give AI customer services thumbs up, they are sending me a new controller to replace the old as well.

I have a couple AI 1.9's and still have a 5-7f difference between the back right and front left corners, even with marble shelves. Anybody have a solution for this? The hydrion sales rep told me their ovens heat from all 5 sides, can anybody attest to this?

Same issue here. I adjusted my pk so its the same as the sides and corners that are hotter so i dont burn stuff. I was burning the sides before i made this adjustment. It would be nice to not have to compensate for this issue. The best wax puff i made was on the top shelf in the back left corner fwiw.

 

[rb extractors]

About 8-12 hrs at 110-115 depending on slab thickness, strain, etc. I don't run the vac the whole time though , also don't forget to flip

Also gotta give AI customer services thumbs up, they are sending me a new controller to replace the old as well.

I have a couple AI 1.9's and still have a 5-7f difference between the back right and front left corners, even with marble shelves. Anybody have a solution for this? The hydrion sales rep told me their ovens heat from all 5 sides, can anybody attest to this?

I'd have to take mine apart to determine this, but it is still an inferior system even if it did have heaters all around.

Something I never noticed initially was that our door was out of alignment, the controller isn't as accurate or customizable as the AI which leads to overshoot of temp when you open door, etc.

I had them give me a big refund or take it back because I was so dissatisfied with it. plus, the price difference between it and the AI isn't that much anymore

 

[Permacultuure]

The hydrion sales rep told me their ovens heat from all 5 sides, can anybody attest to this?

All five sides, I doubt it.....I have a few hydrions and have been a supporter of them in the past. I can tell you there are large variations in temp throughout the ovens, 5-7 degrees. I'm siding with RB on this one now....With the AI's being domestic and having low temp controller standard now, I'd agree that its the best choice. If Hydrion wants to stay competitive they need to have a major price drop, otherwise they're not worth the trouble....

 

[analogcricket]

anyone have experience with using glass as shelves?

 

[rb extractors]

I'm sure glass would work fine holding heat like granite

 

[Backyard Farmer]

Can you only get the PK setting if you have the new controller? I have the old controller and don't have that option.

I should call them monday and get a low temp controller sent to me if you guys say it makes a huge difference.

 

[prune]

anyone have experience with using glass as shelves?

I would guess that tempered glass would be necessary and make it a bit more expensive than you were hoping. I've been wondering why someone hasn't tried some nice steel plate, it should store higher btu's and give them up more readily?

 

[Gray Wolf]

I would guess that tempered glass would be necessary and make it a bit more expensive than you were hoping. I've been wondering why someone hasn't tried some nice steel plate, it should store higher btu's and give them up more readily?

Some of the big boys use cast aluminum shelves with heating elements and thermocouples in them, so that you can individually control the exact heat zone that the shelf falls in.

I know they are available from Cascade TEK in their larger ovens, and Maxwell at Across International tells me that they do in some of their larger ovens as well.

Just a thick slab of aluminum will work as well and it it makes intimate contact with the heated oven walls, more the better for direct heat transfer from the ovens heated walls through conduction, instead of waiting for the slower transfer of radiant energy in a vacuum.

Steel would work well too, but weighs more, and would have more enertia and transfer heat to the product more slowly. Aluminum weighs about .1 lbs/cubic inch, carbon steel about .283 lbs/inch cubed, and 300 series stainless about .295.

Also don't forget that you are talking black body radiant energy transfer, so use a dark colored shelf, instead of a light colored one, to reduce reflected energy and speed things up.

All variables that could of course be adjusted for in the process, as is currently being done with marble, which transfers heat more slowly that either steel or aluminum.

Alas, don't forget the ass end of the elephant!

Good thermal mass takes longer to heat up, but does a good job of stabilizing temperatures in a narrow range.

The reverse enertia/hysteresis, also means it takes longer to make temperature changes.

For instance, when making wax, some start out at a low temperature and full vacuum, ramping up the temperature as the bubble activity subsides, until it waxes. Assuming a range from 100F to 140F in 10F increments, hysteresis has significant effect on the process, thus providing more variables.

Others start out at a higher temperature closer to 160F, and modulate the vacuum levels, based on bubble activity. In that case hysteresis has little effect.

How ever you do it, your technique must be developed around your variables and with neither technique does it appear to a set the dial and walk away kind of operation.

If you weigh out two equal samples from the exact same extraction and place them in equal film thicknesses on parchment and place those in a vacuum oven side by side, one will complete waxing before the other.

In addition, different spots in the same patty wax at different rates, so at least at this point, it still involves individual artistry.

 

[Gray Wolf]

anyone have experience with using glass as shelves?

No, but as already suggested, it would be a good idea to use tempered glass.

That aside, glass should do a good job. It's Achilles heel is that it cracks if you change the temperature too fast.

 

[RegisPhilburn1]

So are you guys calibrating or auto tuning with the marble/steel shelves in?
I picked up some 13.5"x 15.5" aluminum cookie sheets that fit the AI 1.9 perfectly, but they are pretty thin.


After opening the side of the AI to put my kf25 fittings on I was a bit disappointed to see the 3/8 silicone tubing connecting everything inside, which makes the kf25 bellows pointless. Looking at the connections to the oven it looks like a simple 1/2 pipe thread, I'm going to try to mod out the AI maybe feed heat mat wires in somehow and seal them so I could get heat on each individual shelf. Fuck the warranty. Probably going to get a electric micron gauge to replace the torr gauge. Replace silicone tubing with stainless tubing so I can have a working cold trap which I could retrieve clean alcohol from without silicone degrading as we are all so well aware of. Put a ball valve and filter attachment for vac-release inlet.


All that said, I am having no problems making excellent shatter in these ovens.

 

[icdog]

I auto calibrated with the marble in and I replaced the shevles with 1/8 aluminum plate. I still only have shelf that brings the material to where i want it, the lower level is colder.
The oven is set to 125 and the material is at 115 after an hour of warm up. Works but just one shelf. Hopefully when the planet warms up I can figure it out more.

 

[Gray Wolf]

So are you guys calibrating or auto tuning with the marble/steel shelves in?
I picked up some 13.5"x 15.5" aluminum cookie sheets that fit the AI 1.9 perfectly, but they are pretty thin.


After opening the side of the AI to put my kf25 fittings on I was a bit disappointed to see the 3/8 silicone tubing connecting everything inside, which makes the kf25 bellows pointless. Looking at the connections to the oven it looks like a simple 1/2 pipe thread, I'm going to try to mod out the AI maybe feed heat mat wires in somehow and seal them so I could get heat on each individual shelf. Fuck the warranty. Probably going to get a electric micron gauge to replace the torr gauge. Replace silicone tubing with stainless tubing so I can have a working cold trap which I could retrieve clean alcohol from without silicone degrading as we are all so well aware of. Put a ball valve and filter attachment for vac-release inlet.


All that said, I am having no problems making excellent shatter in these ovens.

I considered silicone mats inside as well, but haven't tried to vacuum one and see what happens. Just a ni-chrome bare element will work in a vacuum for sure.

 

[Backyard Farmer]

http://bakingstone.com/shop/countertop_oven/

I was thinking of having them cut me a few 13x15.5 tiles. The heat transfer rate of the material is 4.6 btu in / sq ft F

Waiting on the low PID controller, supposed to be here tomorrow, but it's still it New Jersey lol.

What vacuum pumps are you guys using with your ovens?

 

[bull619]

http://bakingstone.com/shop/countertop_oven/

I was thinking of having them cut me a few 13x15.5 tiles. The heat transfer rate of the material is 4.6 btu in / sq ft F

Waiting on the low PID controller, supposed to be here tomorrow, but it's still it New Jersey lol.

What vacuum pumps are you guys using with your ovens?

I'm using a Yellow Jacket Bullet 7CFM. Works great.

 

[Gray Wolf]

I considered silicone mats inside as well, but haven't tried to vacuum one and see what happens. Just a ni-chrome bare element will work in a vacuum for sure.

Now we've tried it and it works well if you out gas the mat first.

Our new Cascade TEK test sled, has one shelf with silicone rubber heat for testing. The silicone mats came from Omega and were ordered already degassed by Cascade TEK.

 

[HighStateToke]

When one is looking to choose the best material to replace the racks, would a high thermal conductivity or thermal insulation properties be desired? I can see benefits from either...more heat being displaced to the slab, or more heat being retained in the rack.