wooden hot tub

[beav39]

anyone ever build a wooden hot tub and if so how did you go about it and what type of wood did you use ,i would like to heat it with my outside wood boiler

[MemphisLogger]

I've never manufactured one but I've assembled a few. All of them were made of Redwood.

Some had jointed bevels on the staves and some didn't. Bottoms were tongue and grooved and fit into dados cut an inch or so from the bottom of the stave and were banded with 3 or more steel hoops joined with screw clamps. All of them relied on being swollen with water to seal the joints.

All of the tubs I've assembled were heated with snorkel stoves.

I've thought about making one for myself out of QS White Oak but it's pretty low on the honeydew list.

 

[metalspinner]

What about making it like a boat but in reverse?  Of course rubbing your bottom on fibreglass may not be the best idea. :-\

Ianab has a cool pic in his gallary of one.

[isawlogs]

   Worked on one that we build from eastern white cedar , tongue and groove on a slite angle ( sure wish I could remember )  :-\  we used 1/2'rod that I had rollled and welded a threaded rod to it , and made a 1/4" washer from a flat bar welded it to the other end of the rod , and this was used as the band , I sortof copied what was used on the silo at home .  ;)  It worked fine . the floor was set in a dado give or take a couple of inches from the bottom . It was to be heated with an outdoor wood stove boiler .
  This sat on a cedar deck we put up for the hot tub .. Just need to remember that those tubs get heavy , what ever you put under it for support make sure it is strong enough .  :P

[johncinquo]

Sounds like your getting too complicated.  Try this route.

[Gary_C]

Do you get broiled or fried in that tub?    :D :D :D

[isawlogs]

I think one needs to be fried to get in there 

[Bob Dilts]

Hey Beave,
We have built 4,6ft, hot tubs out of eastern white cedar.
If you go to my gallery, you can see them.
We heat ours with an outdoor furnace You have to use a stainless steel heat exchanger because of the chemicals we use for sanitation.
I used the Logosol planer with a hot tub profile knives.  If you are interested, I'll post pictures of the profiles of the staves and anything else you need to know. Bob.

[beav39]

hello bob dilts very nice work on your tub i would gladly like to see all the pics you can posts on building your tub.do you have any specs on building them or did you design them yourself?also do you have any pics of how you hooked up your heat exchanger?   thanks for the info           scot

[Bob Dilts]

I'll do my best to explain how we made our tubs,kinda new at this so bear with me.Really enjoying FF.If you don't have a moulder you can cut your staves on a angle with a table saw 4 degree I think. Used four 4x4 for the base to fasten to. Made the base out 2x6 t&g tried using 2x8 found them to hard to work with.Staves are 4' long. Used a dado blade on a radial arm saw to cut grooves in staves,aprox 5/8" deep and the width is1/8"smaller than the thickness of your base.Cut the groove so the tub sits on 4x4 not on staves apox.3" from end.Our tub is 6ft in dia.Used a jig saw to cut out the base on the first ones,now we use a router with a piece flat bar attached anchored in the centre does a much nicer job.Sanded a bit of a bevel on the base to get staves started on,Quite a bit of pounding to get them in place.We used different widths of staves 2x4,2x5,2x6,makes it easier to get the fit for the last ones .Use stainless screws to build your seats.
   For banding we used 1 1/2"x1/8" flat stock with 1/2" threaded rod welded on one end and 1/2" pipe welded on the other. You need aprox.19' to go around a 6' tub. We used 4 bands per tub probaly only need 3.
  To control the heat exchanger we used a 24v actuator valve controled by a thermastat on the return line to the tub.
   Filling the tub for the first time is quite an emotional experience,watching water leak out of so many different places at one time. Can take a few days for the cedar to swell and stop leaking.
   I'm a long ways from being a expert at hottubs,but it gives me something to do on the nasty days. If you have any questions I'll do my best to answer them. I posted some more pictures in my gallery hope they help.Bob

[thecfarm]

The stainless steel exchanger is not cheap.I just paid $400 for one for my hot tub.They may be cheaper.This is what the dealer charged me.With 3 ciculators for my outdoor furnace I was hoping to keep the light bill about the same.Will take a couple years to pay for itself.

[beav39]

The stainless steel exchanger is not cheap.I just paid $400 for one for my hot tub.They may be cheaper.This is what the dealer charged me.With 3 ciculators for my outdoor furnace I was hoping to keep the light bill about the same.Will take a couple years to pay for itself.

where did you get your exchanger through cfarm?

[beav39]

bob thanks for the new pics very helpful also your info on building the tub is great.by the way welcome to the forum there is alot of great info and great guys to chat with here.  bob ,you said you put an acuator on the return line to the tub does this control the temperature in the tub and if so how does it work?also on the staves i assume that the notch doesnt quite fit exactly tight to the base do to the 4 degre radius ?do you run your tub year round?and do you have a drain hole as well?        thanks     scot

[thecfarm]

I have no idea where he got it from,I just know the price.He dropped off all the fittings,pipeing,heat exchanges in one stop.Check Memco in Jay,897-4100.They may have them.I can find out if you want.I suppose he could order one for you.He's the Heatmor dealer in Readfield,Bestway Wood heat,685-3900.

[Bob Dilts]

Scot I put a thermostat on the return line to the tub, it controls the valve suppling hot water to the heat exchanger.

The 4 degree angle is on the side of the staves only if you don't use a hottub profile,has notthig to do with notch.
We don't use the tub in the hot weather,but we won't drain it.Tub dries out and takes to long to seal again.
Bought our heat exchanger from Wood Doctor,aprox.$300.00 I think.
Hope this helps. Bob

[beav39]

cfarm thanks for the info ill check into it im not starting project until snows gone,whenever that comes   ha ha!!                            bob great pics and info thanks a bunch i really like your tub very good craftsmenship! i like the way you set up your temp control,bob one last question,i assume that nothing holds the staves together ,only the steel rings?i dont have a moulder so i will be cutting the 4 degree bevels on the table saw,would it be better to get tounge and groove?

[Bob Dilts]

Scot I don't know if T&G would be better or not.I think it would be a poor seal because of the round shape. Once it's together and you have over 600 gal. of water in it the bands do a pretty good holding it together.
  The first one you build is the hard one, the rest are easy.
I wonder if anybody else out there has a wooden tub???
You have to be careful with the sanatizers you use with wooden tubs. Best to use bromine over chlorine from what I have learned. though I use chlorine because i'm allergic to bromine.
  Good luck

[beav39]

thanks bob you have been very helpful     stay warm    scot

[sawdust]

I love tubs!



I had a set of knives made for an Alco Planer. I tried all sorts of other ways of making the joints this works best i have found.

I had a local welder build stoves for me out of aluminum.

http://www.agt.net/public/coambs/graphics/tub.jpg

I use two bands on a 4 foot tall tub. This rain barrel is on a 3 foot diameter disc of plywood. The bands are 1/8 by 1.5 inch mild steel. The closing mechanism is an overlap on the steel and a two inch piece of 1/2 id pipe welded to the end of the steel and another welded about 1.5 feet in from the end. I use grade 8 threaded rod, grade five will strip out. I use connector nuts they look nicer and are easier to wrench on. The last stave I always  rip to size on the table saw use wood screws to put it back together. Use a stapler to hold the staves lined up while assembling and a rubber mallet to whack them into place try not to have the stave tight in the dado to the base, a little wiggle room is good.(1/8 inch)  A couple nylon load straps are good to tighten up and hold thetub while you are putting the bands on.


Before I built the planer knives I used to bevel all the sides on the staves, I also put a spline in the top four inches. The angle is dependent on the number of staves.




The  base is sloped so that the water always contacts the aluminum. Otherwise you geto hot spots and the metal bends making an airpocket, eventually the metal burns through. the legs have holes so the water drains and the legs do not freeze. the back side of the furnace is curved to match a 4 foot diameter tub, it will also fit a 3 or 6 foot. The height is designed for a four foot stave. 3/4 inch plywood base and four inches below the dado gives a max of 3' 7" water depth. There are tabs for screws so you can anchor the tub to the floor and tabs to screw a wood shield on to the swimming side.



This photo is of the top side the tube on the left is air intake and it stops just short of the bottom. bout two inches short
middle is the wood load and it has a cap on it. the tube way off to the right is the chimney.





sawdust

[beav39]

sawdust i would like any info you have on building tubs and stoves thanks

[Don_Papenburg]

Bob ,   Have you tried hydrogen peroxide?  I have heard that it works great  Some say better than chlorine.

[Robert Long]

This is a little off the subject of hot tubes, but Martha Stuart had a segment on a craftsman who builds wooden tubes for inside the bathroom.  It looked a lot like a little dingy boat but it was well done.

Robert

[Bob Dilts]

Don, I heard of hydrogen peroxide being used in tubs. I don't no where you find info on it amounts,testing,ect. Would be very interested in finding out more about it.

Robert, I think any tub you put inside would require a liner, they tend to leak for a while. Did those tubs look anything like this one,we built it just to say we could.

[Robert Long]

Bob Dilts;

NO, sorry, it looked more like a boat with a flat bottom, curved sides and a back. It was very nicely done and it did not leak.

But, yours looks great too! 8)

I will try to find info on it somehow.

Robert

[LeeB]

There's a link to on the forum some where I think. They were nice but verrrry pricey.