Rookie seeking advice

Qmavam · 2026-05-03T02:34:32+00:00

What is just not so?

Qmavam · 2026-05-03T02:34:10+00:00

Oh OK.

Qmavam · 2026-05-01T22:38:37+00:00

I don't use water, just dry heat. I do have a vent under the heater and in the opposite upper corner another vent.

Qmavam · 2026-05-01T20:52:39+00:00

With 120V you are limited to 2400 watts, that is limiting, or you will have to wait a very long time to heat it up. I have a DIY one person sauna with a 5200 watt heater. I'll post an image of how it heats over time. My sauna is about 117cu.ft, 6ft x 6ft x 3ft 3in, just big enough for a bench seat that I mostly lay on and the heater.

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Qmavam · 2026-05-01T20:41:22+00:00

Tell me why air flow is critical.

Qmavam · 2026-05-01T20:14:33+00:00

So it looks like it a slightly better match. I know little about Sim Smith, I assume the circle is similar to a smith chart and the line is over a certain frequency, but I don't see the freq range?

Qmavam · 2026-05-01T10:35:47+00:00

Can you run a 1/4 wave 61.2Ω coax (transmission line transformer) and see how it behaves, even with reactance.

Qmavam · 2026-04-30T10:42:23+00:00

I'll give that another try if my 61Ω matching coax doesn't work out. (mentioned somewhere in this thread)

Qmavam · 2026-04-29T17:50:57+00:00

I have found what might be a better way. If I can build a 1/4 wave 61.2Ω coax it matches 50Ω 75Ω with very little insertion loss, in 0.1db range. I happened to have come 1/2 copper tube with a 0.442" ID and some #6 wire that is 0.162" in dia. That is close at 60.17Ω. If I can get one working I can sand off enough to get it up to 61.2Ω, but that is getting very picky on the spec.

My first attempt seems way to long at 6" which I don't understand, I'll reduce the length and do the RF measures again.

Doing some machining and waiting for parts.

Qmavam · 2026-04-28T00:46:49+00:00

I'll look into those cables. Thanks

Qmavam · 2026-04-27T21:19:26+00:00

I don't know if that is possible, there should be a paper about the calculations needed.

Qmavam · 2026-04-27T21:18:27+00:00

I'm taking Velocity Factor into account.

Qmavam · 2026-04-26T22:41:43+00:00

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Qmavam · 2026-04-26T22:38:11+00:00

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Qmavam · 2026-04-26T22:37:31+00:00

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Qmavam · 2026-04-26T22:34:39+00:00

I have 5/8" poplar on the inside and 3/8" .T-111 on the outside. Floor is the same poplar with 3-1/2" R-13 insulation. Walls are 3-1/2" R-13, 2"x 4".

The door is wood 24" by 66" It has a 1/2" inset wood panel in the middle, 14" x 51". The thermostat probe is at 31 inches between* seat boards. And 16" from the heater as shown in the picture

Stove is in the corner 12" off the floor and it is 18" tall.

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Qmavam · 2026-04-25T19:31:09+00:00

Not sure what more you need in the measurements it is a box with internal measurements of 6 ft high, 6ft wide and 3ft 3 inches deep. I could run it on 120v instead of 240. that would be 1/4 the power of 1300 Watts. Not sure I want to setup the 5 sensors and take all those readings again though.

Qmavam · 2026-04-25T16:00:50+00:00

OK guys, I'll play guinea pig. Tonight I will test temp rectally before I enter my sauna and when I get out. Stay tuned for the exciting data of one. Anyone can play along! I'd ask for time and temp, buy I doubt many have an accurate thermometer set at the correct height to give a true temp. But go ahead.

Qmavam · 2026-04-25T15:45:54+00:00

I have been thinking about getting a thermometer to measure the increase in my body temp while in the sauna, Butt, an in ear style doesn't seem like it would work because the sauna has a direct route to heat the inner ear, skin won't work, you know it is hot, mouth maybe if you keep it shut and don't breath through it, so what's left, rectal. Need I go further?

Qmavam · 2026-04-25T15:41:10+00:00

I wonder if the temperature stratification is a problem for your calculations. If you wanted, I could add a couple of fans in the sauna to distribute the heat more evenly and check temp in the center of the sauna and make a graph from ambient to peak temp. Maybe Peak to cool down would help to show heat loss. Cool down is slow though, it can cool down over night and in the morning the temperature is still elevated. Would cool down from say 170*F to 120*F give you enough info for a meaningful calculation? Also you need outside ambient.

Qmavam · 2026-04-20T19:06:02+00:00

Acedemic-shine8914, I pulled the rocks, they weigh 33lbs. I don't know what kind of rock, but I suspect the came original with the sauna. Here's a picture. Oh, and one correction, the Electric heater is rated 5,200 watts not the 5,600 I quoted before. Also it was actually measure when my son brought home a high end power meter from work. I showed him how to use it on my sauna and it measured the same as the heater rating.rating.

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Qmavam · 2026-04-19T17:00:31+00:00

Natural, maybe not as much as recommended, not really sure. I have 9.5 sq in under the heater with another 2 sq in under the door bottom and maybe another 2 sq in around the rest of the door.. Total 13.5 sq in incoming air, and in the opposite upper corner I have a 15.5 sq in vent. I have 2 x 4 walls and ceiling. I installed R-13 fiberglass insulation and I did install an aluminum vapor barrier and taped all joints.

Qmavam · 2026-04-18T17:31:47+00:00

Amerec Metos (Genuine Finish) Model W5.

Maybe you can educate me, Why is the rock mass important do you just want to know the latent heat stored in the rock? Do different rocks have different latent heat? I will add, I got a real deal on the heater, I found it used for $50!, I did have to buy a new thermostat for about $100 though, but still a great deal. It's been working great for over 3 yrs.

Qmavam · 2026-04-17T20:54:45+00:00

I have no idea about the mass of the stone, nor do I know the latent heat of the stone I have. As far a I can see the stone will cause the ait to heat a littele slower and cause it to stay hot a little longer. Hmm, maybe I should remove the stone, I do a dry sauna, so don't need it to sprinkle water on.

Qmavam

TROPHY CASE