Radio Frequency Vacuum Kiln

everybody it's Paul from legacy lumber and in this video I'm going to give you a description of how our radiofrequency vacuum kiln works [Music] we just unloaded it this morning and time is of the essence we like to unload and load it right away so we're actually loading it already so we've caught it kind of not about halfway but about a quarter of the way done there's four layers that we're gonna load in here so we're gonna have a look now this is the vacuum kiln that you see in the background and what it is is a about a 20-foot long chamber that can fit a timber card about sixteen and a half feet long so you can see here on our timber card it's always a jigsaw puzzle so we have two pools of Canadian black walnut that are about eight to eight and a half feet long that way we add up to our 16 to 16 and a half total lengths that we have available in the kiln so sometimes it's a little bit more hard when we have a 12 foot long pool and then we kind of have another four feet four and a half feet that we got to make up which will usually do with some cookies or some shorter material maybe some coffee table type material but in this case we have some beautiful three-inch thick this is all salvaged Canadian black walnut all of our lumber comes from local tree service companies so they're already being cut down we then saw Millie here on site and for the 3-inch walnut we like to air dry it for four to six months to give it optimal color as well as even in the vacuum kill and it's gonna have a little bit better moisture content so a lot of people will say well what's a vacuum kiln there's a few different kinds of them this one specifically is a radiofrequency vacuum kiln and basically what that means is that there's a chamber that all the woods gonna slide into the door is gonna closed and then we're gonna initiate a vacuum pump which will suck out the majority of the oxygen by doing that removing the atmosphere pressure and we're able to vaporize water at a much lower temperature out in the standard atmosphere here were about 101 kPa inside the kiln once we turn the vacuum on I'm gonna pull it down to about 7 to 10 kPa which will boil water or vaporize water at around 38 degrees to say 42 degrees as the wood dries out I'll raise the vacuum up a little bit to get to higher temperatures but in general you'll have lower temperatures in a vacuum kiln drying the other advantages are that it holds the material very very flat inside the kiln we can see come here this is the chamber we have a hydraulic press that's gonna push down on the wood and as the wood dries it will actually adjust and apply more pressure this is the top of the chamber and I've actually had wood slide in here literally touching this talk and after the week or two weeks of drying it's about three to four inches lower so that's how much the wood will shrink over about a four foot tall kiln cart so in the vacuum kiln we have these plates we can see them here and this is actually gonna transfer the radio frequency from a plate to the other plate and the wood is in between what we're trying to achieve with that is that the electricity that's flowing from plate to plate is actually shaking the water molecule at about six thousand eight hundred times per second that creates friction and that creates Heat we need that heat energy to warm the wood up and then to a certain temperature to be able to boil that water away so on our kiln cart we're gonna have a negative sheet which is the whole body of the kiln and then we're gonna load on about nine inches ten inches thick of wood and then we're gonna have another sheet once we put that sheet on this is going to be the positive sheet and basically it's not connected to the negative sheet but it is glowing electricity between the negative and positive shaking that water molecule which is then generating the heat side effect of this is that the wood is actually drying from the inside out so when we start drawing will actually have the outside of the wood will be almost in like a steam bath a really nice environment for the wood not necessarily for us because there's gonna be no oxygen in there and wouldn't be pretty if we hopped in the chamber but for the wood the lack of oxygen and the hydraulic press all is a whole system to keep the wood flat during drying and restrict the defects basically speed is the third kind of side effect of the vacuum kiln in that we can take this three-inch wood which is generally about thirty percent moisture content now probably a little higher because that's right on the outside probably more in the 4045 range we're able to dry this in about eight to ten days through this vacuum kiln with virtually no no degrade in the wood which is pretty awesome so it's it's an exciting tool to have that we have here at legacy lumber and we'll do some more follow up videos get a little bit more in depth on how this machine works basically this is what we do every eight to ten days we load the vacuum kiln we unload the vacuum kiln and you can check out the wood here this is cut on our custom sawmill up top these can be some beautiful computer desks put a pair of these together you got a really nice dining table or it's ready to become your bar top and have some drinks all right so we've spent pretty much the whole day reloading the vacuum kiln it's a lot quicker unloading usually than loading it because when you do load it it's a bit of a jigsaw puzzle and you want really good contact wood to wood surface so as we can see here we have about four feet of total height we also have about four feet of width and the card itself is 16 and a half feet long so we've maximized our yield pretty good we have an 8 foot pool an 8 foot pool two more eight footers then we have just a pair of 10 through 12 I forget I think actually 11 footers and then right here we made up the extra space with some four and a half five foot long slabs so I always try and maximize the amount of wood that goes in here because not electricity it uses is going to be the same so the cost to dry the wood it just makes sense to put as much in as you can and we're gonna roll it in right now so let's do it I'm going to look at the wires as we roll it in that nothing's catching or bumping it out of the way because we do have these things are going to be a positive signal talk middle and bottom is a negative signal so we don't want those plates interacting in a way that we don't know we just don't want any shorts basically what's going on let's go to make sure all the cables good so the whole timber carts been rolled in what controls the drying process is the temperature of the moisture in the wood so we're gonna drill a hole in a single slab typically I do it in the biggest slab the longest one because it's going to have the most moisture for the the longest time so I'm gonna drill my hole this would be good here even thermometer which you want to be careful and not drive your timber card over because you cut it in half which has happened twice what we've repaired it may be time for new cables soon so we're insert our probe that's in there and you just want to ensure that this cable this is a positive plate this one just want to ensure that this cable is nowhere close to that because they can get zapped actually so from here we look pretty good on the top here this right here is a hydraulic platen that's going to push and hold the wood down the entire time as it drives mitch is going to turn that on now so we can look up top here so you can see how that's gonna hold the wood flying and as the wood shrinks it's gonna continuously add pressure and try and keep the wood as flat as we can we're gonna go ahead we're gonna close up the door now so big crazy heavy door one last look make sure everything's okay oh you know what in my haste here I actually forgot something so the cart the final connections is that it gets grounded to the body then one of many grounding spots but this is the last one that you can do so now we're ready we double-checked everything we did notice something we didn't hook up so we're gonna close up the door boom our submarine pipe handles and I get a little tighten so if we go inside here I'll actually show you the control panel to operate the kiln so this is the the brains behind the whole operation I guess this is a 20,000 watt microwave and this also controls the vacuum pressure as well as the temperatures so how does a touch screen here that we can touch it lights up the load that we just took out of the kiln had a hundred and fifty two hours of heating time so probably that was in there for six days of heating time but actually the load was in there for eight days so it just shows you it does shut on and off as it reaches its max temperature it drained about 700 litres of water over to the last load we don't care about all of that now though because we want to erase it so I can come in here I got a bunch of settings we can go right in here we can go reset the data are you sure yes it's gonna ask us again data reset we're all reset back to zero and then in here I can set my min and Max temperature so when I'm doing three inch thick walnut I'm gonna have my max temperature at about 40 degrees Celsius and I'll have a low of about 38 degrees so this machine is going to heat up to 40 degrees Celsius once it hits that it'll shut off and then cool down until 38 and then turn back on and heat to 40 and it's gonna repeat that throughout the eight to ten day cycle I'll be raising those temperatures along the way there's also a vacuum pressure which we're in an atmosphere of 101 kPa and I'm going to be pulling it down initially to nine kPa and then it will rise to twelve again the vacuum pump will kick on and pull it back down to nine and it'll cycle just like that to confirm this and we're going to hit the start button so this is going to turn on a fan I apologize for the noise so this is turning on the high frequency generator and then it's going to build up some electrical charge so we have to wait for a few minutes until we can process for the next step we're gonna see here that the voltage turns on and then we gotta wait a few minutes for the hit this next button in the meantime I'm also going to hit the vacuum so this is gonna turn on the back you pop didn't actually turn on the back you pup to have my air compressor unplug then go plug my air compressor in that will turn the vacuum pump on and then we're going to go from there in about eight to ten days we're gonna have a nice dry load of wood along the way if you don't already follow on Instagram I do a lot of story times about this machine so you can kind of glimpse into some of the smaller details of what I'm doing as well as follow along as this what's drying you can see our progress and check it out so I really appreciate everyone watching the videos that we've been posting thanks again if you want to stay updated please subscribe and if you liked the video like like it like it like it and comment below if you have any questions about this process or some video if you'd like to see us produce please please comment below all right [Music]

Channel: Legacy Lumber

Views: 54,971

Keywords: wood, woodporn, paul lemiski, lumber, legacy lumber, mississauga, erin, rockwood, ontario, canada, lumberjack, canadian woodworks

Id: sNPXnpMKPjk

Length: 11min 16sec (676 seconds)

Published: Tue Jan 08 2019