Servo / Damper pictures


 

John Case

TVWBB Member
Since Bryan upgraded v9 to include more servo control functions (Thanks Bryan!!) I was hoping people would post pictures in this thread of how they are implementing a servo into their setup.
I did a search for servo & damper but only found a few pictures of how they implemented the servo (see below)
By posting a picture of your setup this would give others the ability to use or modify what others have done. I believe this would be a huge benefit to others.

Thanks in advance for posting a picture of your servo setup.

I've includes some pictures of what I found

Ralph in this thread
PingPongValveExView.jpg


ServoDamper.jpg


PingPongValveFanAdapter.jpg


D Pert in this thread
IMG_4887_zps35700807.jpg


D Pert in this thread

IMG_56971.jpg


John
 
This is the rig I've been running lately....

ServoFan.jpg


I needed a valve badly before the HM code was changed to support running the servo damper and blower at the same time, hence the little ping pong valve I created... Now that I can run the servo with the fan I've been doing things that way instead. One great thing about it is (thanks to Bryan's code) you can choose to run the fan only when the damper need be opened 100%, this gives you fast stoking of the fire and then lets the natural flow of the servo damper take over (which is preferable in Kamado style grills that hold heat really well). OR, you can set the HM to use the fan in the traditional manner blowing at a full range of speeds to control the fire and set the servo damper to operate in fully open/closed mode. In this second scenario the servo takes the place of the ping pong valve or other flap valve you would have on your blower. OR, you can let BOTH the servo and fan to work over the full range of action!

Bottom line is if you have the servo damper and the fan you can cover a huge range of scenarios which will help you control a wide variety of pits and use it in whatever manner works best with your grill. I use the blower only method with my thin walled traditional smoker cause it needs lots of air flow to maintain temperature, I use the damper method with fan assist (fan at 100% only) on my FauxMado grill generally, but switch over to the fan mode with open/close servo damper (and a larger blower) when I do high heat Pizza cooks. So I use my HM in three different modes currently and really love the flexibility having the servo and the blower allows...

As for building one, the servo's are cheap from Amazon or elsewhere, I used the 1.5" PVC coupler as the base for mine, and printed the rest of the (color) parts on my 3D printer... I'm sure you could brainstorm some off the shelf stuff you could use to make the whole thing though...

So far the only issue I have run into with my unit is the 3/4" copper tube I use on the grill adapter is a bit to small to support proper air flow for high heat pizza cooks (even with a very large blower). So I am going to add a second tube to double the volume of air I can deliver to the grill and I should be golden.... If not for the pizza cooks I would be set already....
 
I'm planning on putting together my servo damper this week. I should be receiving the servo today and the rest of the parts will be from what I have at home already ie: left over PVC tubing from my central vac install and I'll be making the flapper from the plastic cover found on a spool of blank CDs.
 
This is not a servo damper pic, per say.... but I'm posting it here because this is my new way to connect my servo damper and fan to the HM.

Since the HM board lacks a proper header for the servo I've had a connector dangling out of the case to connect the servo, I never much cared for this and over time the connector has loosened and likes to disconnect. I thought a single connector for the servo and fan would be the way to go so I rigged up a CAT5 connector with which I can connect both the servo damper and fan through one wire.

HM_CAT5.jpg


Now I just plug a CAT5 cable in that is wired to the fan and servo and it's all done with one simple wire. The connector will also accept a regular telephone cable that could be wired to a fan for fan only operation.

I used my kicked around blue HM case to experiment, I just cut out the opening with a hack saw blade (not in the saw), then super glued some plastic inside to make the connector latch into place, works great! You wouldn't think there would be room for more stuff in the case but I guess there is.... I left the original connectors for the fan and servo in place so I have the option to use either/or...

I've been wanting this for a while, here it is, now I'm happy.... lol
 
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This is not a servo damper pic, per say.... but I'm posting it here because this is my new way to connect my servo damper and fan to the HM.

Since the HM board lacks a proper header for the servo I've had a connector dangling out of the case to connect the servo, I never much cared for this and over time the connector has loosened and likes to disconnect. I thought a single connector for the servo and fan would be the way to go so I rigged up a CAT5 connector with which I can connect both the servo damper and fan through one wire.

HM_CAT5.jpg


Now I just plug a CAT5 cable in that is wired to the fan and servo and it's all done with one simple wire. The connector will also accept a regular telephone cable that could be wired to a fan for fan only operation.

I used my kicked around blue HM case to experiment, I just cut out the opening with a hack saw blade (not in the saw), then super glued some of the plastic I removed inside to make the connector latch into place, works great! You wouldn't think there would be room for more stuff in the case but I guess there is.... I left the original connectors for the fan and servo in place so I have the option to use either/or...

I've been wanting this for a while, here it is, now I'm happy.... lol

Ralph,
I was considering do the same type of arrangement with at cat5 cable. I was considering also seeing if there were enough wires to also include the probes in the cat5 cable as well. I have to not counted yet to see if there is enough. Thinking now about it I believe the following would be needed:
2 - fan
3 - servo
=
5

8 wires in a cat5 only leaves 3. If the ground can be shared for 2 probes then it would work. (as long as I counted correctly)
 
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Yeah the servo's ground can also be used for all the probe grounds, meaning you can use the remaining 3 wires for 3 probes.
 
Why not break it out into 2 separate jacks, 1 for probes and 1 for fans + servos. This would probably be less clutter since the probes are usually near the top of the cooker and the fans and servos are near the bottom.
 
The main reason I added the CAT5 jack is because there is no proper jack to plug in the servo, and since the fan and servo are together as a unit I thought they should be wired together with one wire. (I have grown tired of being careful with the makeshift servo connector, and never liked the idea of having it's connector dangling outside of my HM case in the first place) Now I can plug and unplug the servo from the HM in a more proper manner, and have the option to include the fan power in the same cable. (or I can still use a separate wire connected to the original fan port)

As for the probes, I don't know if I am on the same page... Cause sometimes I use just one pit probe, other times I need a meat probe, more rarely I need two meat probes. So my probe configuration changes from cook to cook. The probes are a PITA even when they are connected individually, they love to tangle, so I would think having them all tethered to one CAT5 plug would be a nightmare. Not to mention that you would have to alter the probes and remove the plugs from them to do this. So I am plenty happy with the way the probes connect currently and see no good reason to change.

Although, as Bryan stated, there is already a ground in the plug for the servo which could be shared for the probes, so you could actually attach 3 probes to this CAT5 plug along with the servo and the fan if you wanted to. The wires I have in the CAT5 jack right now are Servo (Gnd, +5V, Control), Blower (+12V, Control), if Bryan does flip flop the fan control so the 12V is pulsed rather than the connection to GND that would free up one more wire and you could do all 4 probes with this one CAT5 connector (along with the servo and fan)

I had asked for a CAT5 or phone jack to be added to the HM board (to replace the current fan connector and integrate the servo into the jack), Bryan was reluctant because the HM board is jammed tight as it is and he didn't think it could be done. Now that I have this worked out I am fine with this setup, though it would be nice if the HM board would have a header for the servo and fan to wire in this new jack if you wanted it. (I don't think that would be as difficult to accomplish as adding a CAT5 jack to the board?) There is a place to wire in the fan directly to the board (two spare holes under the fan connector) so I connected the fan wires there, but the servo wires all had to be piggy back soldered to the solder joints of the components. Not an impossible setup, but not the best either...

The way I setup this CAT5 jack it is not "mounted" to the case, so If I need to remove the HM board(s) from the case for any reason the CAT5 jack will come right out with it, no problem... I'm not sure yet if I will rework the case design to print with the hole and latch area for the CAT5 jack or just continue to manually alter the case to fit the jack, it was pretty easy to do with a hack saw blade and some super glue (to mount the plastic for the latch). I doubt I would have the unit in hand yet if I had gone about altering the 3D case design and printing it, and if I did I would have to alter the case design manually every time the case was updated unless Matt or Tom decided to include this version in their lineup (I'm not even gonna ask, they already maintain two case designs for two different displays). So the availability of a case with this feature may be questionable, but you can always alter your case on your own.... (FYI, I am using the case for the larger 4-line display, which I believe is a tiny bit larger than the case for the standard 2-line display. I am not 100% sure it will work the same in the smaller case, because I haven't done it, but I have looked at it and I am reasonably sure it should work out the same)

I opened up my case and shot some pics of the inside today in case anyone was interested in doing it themselves. I got the CAT5 jack from Home Depot (you can see the label in the picture), it is the type where you just punch down the wires and it snaps into a standard wall plate. I inspected the wall plate at the store to get an idea how to make a mount for it, I didn't end up mounting it exactly the same as the wall plate in the end. I just made sure the hole was tight to the jack on all sides and used the latch to prevent forward and backward motion. One piece of plastic glued in was all it needed, I used a piece that had an L-shape cause it was easier to position while gluing (and I had scraps handy), but you could actually use the piece of plastic you cut from the case glued in place to do the same job. (BTW, I just cut straight down with a hack saw blade on both sides then snapped the plastic out with some pliers. I cut down about 6mm on the top and 10mm on the bottom. The cuts need to be about 15mm apart)

Here are the pics:

CAT5_Inside.jpg


And here is a pic showing the piece of plastic I glued inside for the latch. I used an orange plastic scrap so it would be easy to see what I added...
CAT5_Mount.jpg


...and a pic of the whole thing assembled to make this post more comprehensive...
HM_CAT5.jpg


The CAT5 jack would have fit on either side, I chose the same side where the probes connect so all the wires would be on the same side. So you could put another CAT5 jack on the other side to use for the probes if you wanted that... (or put the probe jack on the same side as the regular probe jacks, and the blower/servo jack on the same side as the USB which is where I hear the power jack will be moving in future HM versions) I personally like the setup as I have it with the Servo+Fan on the CAT5 and the probes separate, but you have the option to attach some probes to this CAT5 jack if you like, or add a separate CAT5 jack for the probes.... whatever floats your boat! The Home Depot Website shows the CAT5 jacks available in color(s), it would have been nice to have a blue jack but I didn't even think of that when I was brainstorming this at the time.....
 
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As always lots of good info.

I had asked for a CAT5 or phone jack to be added to the HM board (to replace the current fan connector and integrate the servo into the jack), Bryan was reluctant because the HM board is jammed tight as it is and he didn't think it could be done. Now that I have this worked out I am fine with this setup, though it would be nice if the HM board would have a header for the servo and fan to wire in this new jack if you wanted it. (I don't think that would be as difficult to accomplish as adding a CAT5 jack to the board?) There is a place to wire in the fan directly to the board (two spare holes under the fan connector) so I connected the fan wires there, but the servo wires all had to be piggy back soldered to the solder joints of the components. Not an impossible setup, but not the best either...
When I said that I meant that the HeaterMeter v4.0 board had no room whatsoever to put a servo header or jack. It's on my todo list for the v4.1 board though, which is why I was trying it on the test boards I just had made. It looked like it was going to work in EAGLE, but of course the EAGLE part is bonkers wrong so I'm going to have to redo it. I wanted to get the design out to OSH Park before I went on vacation so I just used the component EAGLE already had.
 
Basically copying the D Pert design, I put together my own ghetto damper tonight and have it communicating with the HeaterMeter nicely.

Materials:

Left over central vac pipe
Coat Hanger
Thick rubber cutting board for the flap

The cutting board flap isn't making a perfect seal, but I think it's still considerably less natural convection than via the fan. I'm going to try and add some material to the flap to see if I can get a better seal.

8dooR2Sl.jpg
 
Bryan, can I take a look at your proposed changes to the board layout? I was hoping that on the next iteration we could try to place inputs/outputs in a way that takes advantage of all of the dead wall space so we can minimize the case expansion needed to accommodate screws. Basically, if the connectors on the bottom of the board (power, fan/servo) could be moved to the side opposite the probe jacks (side with rpi usb/ethernet), that would basically make the case have 2 walls with no jacks creating a lot of free space for screws.
 
I have no layout yet, but I can tell you:

-- The power input barrel jack is making 90 degree turn to face the left edge
-- The RCA blower jack is becoming another barrel connector and being moved to the right side of the board, most likely on the close side due to not wanting to run the "high current" through the regular components.
-- There will probably be overlapping jacks for the blower jack and servo, which will be an telephone jack (that can do both).
-- I'll try to cut quarter circles out of the bottom left and right of the board so screws can go by without needed to extend the case around the PCB.
 
For those running ceramic egg/kamado style cookers, have you established a baseline BPID to be used with the servo driven damper? Still trying to get my head around BPID tuning.
 
I'll be starting a pork shoulder tonight/this morning. I've got the cooker ready to rock with the new servo setup. Here's hoping for some steady temps!

WDxOn4Dl.jpg
 
Looks good. I love that yellow case. Can you post a larger image of your damper? I'm still trying to gather information from all of the threads here to come up with a desgin for my WSM. Right now, I have the fan only. Good luck. I bought a brisket flat today that I will be smoking next weekend. It will be my first.
 

 

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