Query on snake racks

[Reptilia]

G'day, I built a snake rack consisting of 30 plastic tubs within a melamine shelving system (6 tubs on each of the 5 shelves). Each shelf is routed and within in this is a 6 metre long heat cord woven through each shelf and under half of each tub. The heat cord was plugged into the probe thermostat and set at 35 degrees with the probe in 1 of the tubs. After 12 hours of running the rack. Using a thermometer... the highest temperature the plastic tub had reached was 26 degrees. What have i done wrong?

Does the heat cord have to be in direct contact with the tub ?
What are your thoughts? Im certainly out of ideas....

Cheers. Lance.

 

[Magpie]

I'd check the thermometer.
What's room temp there? Most places it's above 26 at this time of year.
If the thermo works, does the heat cord? Does it get warm, almost hot to touch?
Try it with no thermostat, see what happens then.

 

[wokka]

How big are the tubs? whats the room temperature? Is there a back on the rack? Is there a front on the rack? How much ventilation do you have?
Electricity via, in your case, the heat cord is capable of heating a certain amount of mass being wood ,plastic, air etc by acertain temperature differential.
A certaian amount of electric power (wattage) can lift a larger mass a small temperature differential of a smaller mass a larger tempature differential.
My observation is that about 50 watts of heat will maintain a cubic meter of air about 10degrees above the room temperature if there is no draft. eg to keep a cage 1m x.5m x.5m at 30 degrees in a 20 degree room the 50 watt heater would be on about 25% of the time.
My guess is you have too much volume, too much draft/ventilation and too little wattage.

 

[newtosnakes]

How big are the tubs? whats the room temperature? Is there a back on the rack? Is there a front on the rack? How much ventilation do you have?
Electricity via, in your case, the heat cord is capable of heating a certain amount of mass being wood ,plastic, air etc by acertain temperature differential.
A certaian amount of electric power (wattage) can lift a larger mass a small temperature differential of a smaller mass a larger tempature differential.
My observation is that about 50 watts of heat will maintain a cubic meter of air about 10degrees above the room temperature if there is no draft. eg to keep a cage 1m x.5m x.5m at 30 degrees in a 20 degree room the 50 watt heater would be on about 25% of the time.
My guess is you have too much volume, too much draft/ventilation and too little wattage.

I am taking a guess that wokka is a sparky??? either that or really listened in high school science classes.... :lol:

 

[hugsta]

LMAO Newtosnakes, I think wokka got a little excited about why it could be cool.

Maybe the plastic tubs are just too high of the heat cord and not retaining the heat.

 

[Rennie]

I can't help but I think I'd better tell you not to have the heat cord touching the plastic tubs, me and Ihaveherps have melted through a few plastic tubs by making that mistake.

 

[reptililian]

Hey Wokka.

I like your approach. It is thorough and well thought out. You seem to know your electrics!

Cheers, Lily

 

[da_donkey]

My female BHP has a great rack :lol:

 

[Reptilia]

Thanks for your input fella's. The whole house is built off a heated concrete slab. So heating can be at whatever temperature you want it to be with in any room of the house. With the heat coming from the slab set at zero. The current room temp is 22. I have used a hand gun thermo, digital thermo and analog thermo, all showing the same temp in my room.

Yes the rack has a back on it, no front. The tubs are 18litres each. The heat cord is 6m 50 watt. (Not in direct contact with the tub) but sitiuated within the routed piece of melamine about half a cm under the tub. The maximum temp the plastic tubs get up to is 26-27 with the probe thermo set at 40 (the max). Raiseing the room temp from the slab, the rack can reach 32 with the slab set at 35. And i am sleeping in this room aswell as maintaining my collection of reptiles.

I think i will ditch the cord and buy some heat mat with a greater width than the cord and higher wattage. But will heat mat in direct contact with the tubs melt them?.

Cheers. Lance.

 

[Bakes]

What about putting the heat cord directly under some ceramic tiles?

 

[Surfcop24]

You say that the highest temp in a tub reached was 26 Deg's? Where in the tub was that temperature reading from?? Have you tested the temperature right where the cord is underneath the tub...??? If you do and the temp is 30 or above... I think it would be fine... To do this you might need a infared temp gun...or place the sensor over the heat cord....

Just My Opinion...

 

[herptrader]

What is the wattage of heat cord under each enclosure/tub?
What is the ambient room temperature of your enclosure room?

Heat cord (and heat tape too for that matter) is not designed to get too hot.. otherwise it would melt the plastic. You may find that you have only a small amount of heat output (say 20 to 40 watts) per tub in which case what you are describing would be correct.

Basking lights/ceramics/heat panels etc. might not be part of your plan but would probably be the ideal way to create a day time high temperatures as what you are describing sounds about right for your night time lows.

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[shamous1]

This is one of the most intesresting threads I have read. So much input from a wide variety of people with the main aim of helping a fellow herper out.

This is the type of nice thread others should take note of.

 

[Surfcop24]

So whats the outcome Reptilia??? Have you tried anything different?? How did it go?

 

[ihaveherps]

As Rennie said i have burnt through plastic tubs, but that was due to a kink in the DIY type heat mats, and was my fault for not taking proper care with my equipment. I tried using the heat cords as an alternative but when testing them in various situations i found that they dont transfer the heat through plastic very well, and dont use them since. If you take proper care of the heat tape i stongly reccomend it.

 

[PilbaraPythons]

Heat cord works a treat if your bank is designed in a manner to take full avantage of materials that are more likely to transfer heat. Our racks are all made of steel and we actually have the heat cord adhered to the back inside roof which is a steel roofing battern and consequently makes up the floor of the upper level in the rack. Basically the intire rail gets warm and because they have a reasonable flat surface area is perfect for the back end of the tubs to sit on. I have never seen a better design yet.
Cheers Dave

 

[PilbaraPythons]

A quick look

 

[yommy]

that's a great looking setup pilbara, do you have a full shot of the whole setup with tubs in place for a better visual idea. I wouldn't mind trying something like this as the metals not a problem to get and work with.

 

[peterjohnson64]

Yep, I am certainly with Yommy. Wonderful set up. Way beyond my ability to make but we have some very handy people here who may be able to put them together for us.

 

[peterjohnson64]

Yep, I am certainly with Yommy. Wonderful set up. Way beyond my ability to make but we have some very handy people here who may be able to put them together for us.