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Hello,

I have a 6x36 Keenovo blanket with an integrated controller. This is the controller: https://www.keenovo.com/Digital-Control ... EENOVO.pdf

While bending a side (luckily just a side to be cut up and used for lining), the blanket burnt the side very badly in the lower bout area.

I tested the blanket just sitting out in the open on the slats and when the controller said 300f it was reading closer to 375 - 400 on my infrared thermometer. I reset the controller and went through the process of adjusting the max temp. Then unplugged and plugged, same results. The manual doesn’t seem to indicate there is a calibration of any kind.

Anyone have one of these that went haywire? I have another blanket and controller for now, but wondering if this one is now trash.

Brad


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Yikes. That's awful. I saw those on Amazon. I was intrigued, but no longer so.

Ouch - I've heard from other forums that the basic Keenovo integrated controller supplied can be wonky and the temp swings massive. But nothing about the digital one.
I bought their blankets (5 actually) having made my own controller.
When side bending I use said controller and 2 simple digital thermometers (light bubs underneath) at the same time - I have had an (abused) thermocouple fail in use, and a transformer fry on me on separate occasions, so it's belt and braces here now.
First recourse would be complaint to manufacturer - I've got a feeling they value their reputation highly and may be helpful.
You could change out the thermocouple and test. Failing that curing it, cut the controller/thermocouple off and make your own independent one.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I did try them had issues
stayed with Pro therm

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Same poor experience with the digital controller. After I burned a set of sides, customer service was promptly responsive and wanted me to run some specific tests, which I did using Fluke thermometers, both direct contact and infrared types. The measured temperature was wildly different from the temperature that was set on the controller, by 100 degrees and more. Customer service insisted that it was working normally, an assertion that I found quite perplexing, but eventually refunded the purchase price.

Lately, I've been enjoying bending by hand.

To be fair, I bought it in 2015. Electronics can go bad on day 1, day 101 or day 1001.

Of course I can’t be buying a new blanket every couple years. I emailed them. Let’s see what they say. It’s definitely cooking at ~100 degrees off.


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Here is the response from Keenovo:

-----------------------

Hi,

Thank you for the previous order with us.
We are sorry to know the issue.

It might be a problem with the sensor.
Could you please kindly replace the sensor?
It's a NTC thermistor of 100K B3950-1%.

When you get the sensor, please small bulge with two red wires are the sensor.
Please cut the red wires and connect the thermistor to it.
There is not polarity for the sensor.


Thank You!

-----------------------------------

So, Amazon to the rescue: https://www.amazon.com/Cylewet-Thermist ... stor&psc=1

Looks like I'll get to do a little soldering this weekend if Amazon holds up their guaranteed Sunday delivery.

Brad

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i just took delivery of one of these controllers, hoping to upgrade the dial version that came with my Keenovo blanket. I agree that the dial version took some attentiveness, but did work. I paid no attention to the setting on the dial and ran entirely off my digital thermometer. I've bent around a dozen sets with it with no problems. Cost is an issue for a lot of hobby builders like myself. So the Keenovo is still, in my mind, a good option to get into the heating blanket game.

I'm going to be swapping out the dial controller for the digital one in the next week or so and use it to bend a set. I'll post my results. My guess is that I'll be paying attention to my digital thermometer and only using the digital controller to crank the heat up or down.

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Tony Thatcher
Bozeman, Montana

My inference is that before using a controller/thermocouple/blanket in anger, it would be a comfort to test the combination of the components working together. I bought a Keenovo blanket and assembled my own digital controller, and the controller seems to modulate temperature nicely. Thermocouples are cheap, compared to tonewood, anyway, and buying a few of them to test heating evenness across the mold at the same time might be worth doing. Might be worth doing with whatever blanket/controller combination somebody's using, not just the Keenovo combination.

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Peter Havriluk

Just did a test run with the kenovo digital controller and blanket. U ran it for about 20 minutes working up from 120F up to 250F. My observations were that the controller overshot the target temperature by around 20 to 30 degrees, but then settled in to a relatively stable temperature...around a 15 degree drift. The controllers stated temperature was within 10 to 15 degrees of my decent digital thermometer.

So overall this seems to be working for me. It's definitely a lower cost way to get into the heating blanket game. And a big improvement over the dial controller.

If I were to start bending more than a few sides per year, I would invest in something better. For now I'll keep the limitations in mind and use the digital controller and blanket.

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Tony Thatcher
Bozeman, Montana

The digital controller I assembled (I think LMI uses the same controller core in their finished product) modulates temperature within a range of +/- 1.5 degrees Fahrenheit. Really satisfying considering how inexpensive the finished controller was. Having said that, these things take time and a lot of parts shagging to get built. The LMI price is not excessive when it works out of the box and the only investment is in the cash to buy it. And the instructions will be in English, not Chinglish. But the digital controller sure are nice to watch work.

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Peter Havriluk

Sure is, especially at 1/10th the price for my home assembled unit (wiring diagram, in english, in tuts section, controls +/- 1degC)

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.