WSM Thermometer Mod (pr0n)
 

After much reading, and a couple of posts, I decided to go with inexpensive units.
I got 2 - F&C, 2" thermometers, with 3" stems, off of eBay, both delivered for $20.58. The units come with a wing nut for mounting.

The required hole is larger then the 1/4" claimed. I marked the holes with blue tape, drilled a 1/4" pilot hole, then a slightly larger hole and reamed it a bit until the stem fit tightly.

I tested them in boiling water when I got them, and they are accurate. I haven't tested them on a cook yet.

They do look good. :-D

On my 22 1/2" WSM.
http://imageshack.us/a/img832/5797/thermometer03.jpg

On my 18 1/2" WSM.
http://imageshack.us/a/img825/7292/thermometer02.jpg

The pair.
http://imageshack.us/a/img22/9638/thermometer01.jpg

Bob

Nice job. Let us know how they work.

It will be interesting to see the difference in temp.

Can't wait to see some results, Bob. They do look good, though!:thumb:

Good install Bob!

Looks factory

Some more pictures.

Close up.
http://imageshack.us/a/img204/584/thermometer04.jpg

Side view.
http://imageshack.us/a/img826/9455/thermometer05.jpg

Inside, through top grate.
http://imageshack.us/a/img651/9448/thermometer06.jpg

Inside, no top grate.
http://imageshack.us/a/img818/6836/thermometer07.jpg

Bob

Good job on the install.

I have an Auber temp control probe mounted a couple of inches above yours and the probe is about +30f then the dome lid thermo on my 18.5 WSM.

Looks good but keep in mind that there a few factors that could mislead that gauge.

1. The heat comes up the outside walls of the WSM because of the diverter (water pan). That might lead the gauge to show higher temps than is really happening at the grate.
2. The door is right below it. Unless you have a good seal on the door, it could effect temps either up or down depending on outside weather conditions.
3. If you have food directly over the gauge, dripping could effect it as well.

Looks great!

Nice modification bob, I'm interested to hear how they read compared to the dome.

I finally did a couple of cooks since I did the thermometer mod to my WSMs.
The added thermometer reads from 5-25F degrees higher than a thermometer at the grate. The readings seem to get higher the longer the cook goes on.
It works pretty good, much better than the dome thermometer, which always read 40-50F lower.
I'm happy with the results.

Cook #1 CyberQ pit probe reading.
http://imageshack.us/a/img35/1218/thermometer0201.jpg

Cook #1 modded thermometer reading #1.
http://imageshack.us/a/img84/4637/thermometer0205.jpg

Cook #1 modded thermometer reading #2.
http://imageshack.us/a/img152/2121/thermometer0206.jpg

Cook #1 dome thermometer reading.
http://imageshack.us/a/img805/805/thermometer0203.jpg

Cook #2 CyberQ pit probe reading.
http://imageshack.us/a/img29/5543/thermometer0301.jpg

Cook #2 modded thermometer reading #1.
http://imageshack.us/a/img7/3180/thermometer0304.jpg

Cook #2 modded thermometer reading #2.
http://imageshack.us/a/img801/9595/thermometer0305.jpg

Cook #2 dome thermometer reading.
http://imageshack.us/a/img259/1966/thermometer0302.jpg

Location of CyberQ pit probe.
http://imageshack.us/a/img145/4637/thermometer0205.jpg

Bob

Interesting. I always struggle with where to put the pit probe. Seems that especially if I'm doing several butts, I'll get the probe too close to the meat, and it'll give a really low temp. Sometimes I've actually had to move it a little bit into the cook, which is easier said than done.

I have an eyelet just below grate level on my 18.5 WSM. I used to route the cooker probe on my ET-73 up to the grate and mount it with the clip but any more I just stick ii through the eyelet far enough so it doesn't fall out (and not below meat that would drip on it.) I find that the dome thermometer (I guess I'm not the only one who calls it the dome thermometer. :wink: ) reads up to 50° lower than the grate because it is close to the cold meat. Later in the smoke as the meat gets hot, the two temperatures tend to converge. I don't consider a 10° or 20° difference significant.

Were I not using a second thermometer and controlling to 250° at the dome, I'd probably get 300° at the grate which is where a lot of us like to smoke anyway. Perhaps it is even by design that holding a steady temperature at the dome results in hotter temperature early in the cook.

Think ill put one of these into the mini that I am working on...... I'd really like to have me be of them cyber q's though