# Digital Thermostat conected with 220v voltage regulator diy leather iron

#### ivca33

Joined Jun 24, 2019
12
Hi guys,
I need something like soldering iron but for lower temperature, for my leather craft, to go low as 40c, and at least high as 100°C. There is exact thing but is very expensive,

it is called Fileteuse Edge Creaser and it cost 500$and above. Don't know why but this tips have exposed heater coil, there are also some cheaper replicas, but didn't look much to it, because all this is to expensive for me, at least for now. Only affordable thing that I found for similar purpose and lower temp range is this: It has cartridge heater with built in thermocouple, range from 50°c-350°C. I would need to change this massive tip and make my own. Problem is, I don't know how accurate and durable it is. On this picture you can see that tip although is advertise to be aluminum it is not, it is some alloy painted to look like aluminum, so other parts can be also of bad quality, but than again it is cheap, around 17$.

So my option is this iron, with hand made tips, or alternative, to make one by my own.
If I choose to make it than I don't want just something with dimmer, or something with only on/off regulation, I would like to have both.
First I was looking to pid controllers, they are cheap, and should be better than simple on/off regulator, but one guy who made pid soldering iron said that pid-s are not very good with tip heat loss and that's why are slow in adjusting desired temp.
Than there is dimming /proportional thermostat, like for pets, terrariums etc. i think it would be ideal for me but they are all for animal environment and i think highest temperature is something like 45°C, I didn't found anything higher.

So I need to improvise, but because lack of my knowledge it will be only half automated.
Would this work:
1.cheap soldering iron - 30w, direct 220v AC (already have it)
2.cheap digital thermostat, W3230, XH-W3002 or similar, it has range from -50°to 120°C (4-6$) 3. cheap SCR voltage controller, 220v, 2000w (2$)

I want to add scr voltage regulator, to manually adjust voltage and with that also max temp, to be as close as it can to desired settings, so period between low and high (example 65low and 70high) temperature settings would last longer, and there will be smaller amount of relay switching, longer life, also it will not often and by much exceed top temperature value settings..
I don't know if I'm looking at this the right way. Maybe I will get only slower heating and nothing else, and it will be better to remove SCR voltage controller, and leave iron to work at full 220v with simply on/of regulation.

what do you think guys, also if you think that is good to have voltage adjustment, how does this cheap china SCR regulators react with often on/off switching from temperature regulator. Will it die faster or it is not affected with it to much. I did watch youtube bigclive video and read comments about it , but there is nothing regard this....

(Please keep in mind that i don't have big knowledge about circuits, arduino, etc. For example until two days I didn't know what is thermocouple, but I am good in diy and with little help I can do a lot of stuff as long as they are not over complicated.)

Last edited:

Joined Jul 18, 2013
21,182
The cheaper soldering iron stations now use a Triac method identical to the one you posted.
Are you looking for something with temp feedback system?
The triac is a rather 'crude' method, but works for soldering.
Max.

#### ivca33

Joined Jun 24, 2019
12
tnx for feedback,

Soldering station are ok but the problem is they doesn't go below 180°C. Some things in leather craft will burn at this temp.

First I was thinking that range from 40-120 is enough, but now i realize that real leather creaser, expensive device from first picture in my first post have range 0-400°C. So probably my DIY idea and Digital Thermostat would be short in high range for some applications.

The second, cheap one Iron I posted does have feedback system.
Please look at picture a little better. It is also confirmed on RC forum, they are using it for covering RC plains.
It have thermocouple inside heater catridge. Don't know how exactly is this working, but I guess it should be closed loop system.

Anyway the problem with other irons is temp range. I need temps to go low as 40°C, and soldering irons don't do that.

Joined Jul 18, 2013
21,182
Anyway the problem with other irons is temp range. I need temps to go low as 40°C, and soldering irons don't do that.
I have a cheap Weller WLC100 for portable use and it goes down to zero temp.
Uses a Triac method for control.
On setting one I can grasp the tip without a problem.
Max.

#### ivca33

Joined Jun 24, 2019
12
In my country, I can't find this weller model, there is some more expensive ones, and cheaper look alike replicas but there is again range problem.
I did found it on ebay, but it is to expensive for what it is - variable controlled station. It cost 36$+ 26$ shipping, + probably taxes...so 60$+ I mean, with little effort I can build this for only 2$, just add voltage regulator to my 30W cheap iron.
Maybe this weller have better tips or something but I will not use it primarily for soldering so for me this part doesn't count.

anyway tnx for info, I really appreciate it, if you remember something else please share it

#### ivca33

Joined Jun 24, 2019
12
@MaxHeadRoom do you know maybe does switching of /on from digital thermostat affect life of SCR/triac Voltage Regulator.

Like I mention before I would like to lower voltage of a heater and than use digital thermostat for temp control.

I can't found on internet that someone used this two in same circuit, probably with the reason

#### CharlesWMcDonald

Joined May 16, 2019
233
There is nothing wrong with a PID controller. The guy who told you they would not work probably had an low wattage heater. It is not just the temperature of the device you have to consider, it is also how fast the device can recover from the heat loss as it is used.

#### ivca33

Joined Jun 24, 2019
12
I know this fact, but this is not random guy, it is well known diy on internet (pcbsmoke). He did use mica heating element, but also said that even if we use ceramic one pid would slow the process.

this project is mentioned on more destination, there is also youtube video, and every time there are complaints about slowness.

one guy comment quote: "It works ok, but the temperature swings were very wide when I did things like cleaning the tip on a wet sponge. The PID controller seemed to have trouble adapting to sudden changes like that."

a lot of people said that it doesn’t come anywhere close to that of a high quality soldering station like a Hakko

#### ivca33

Joined Jun 24, 2019
12

Guys, look at this retro station I found at home hahaha. It is pretty accurate considering heater and thermocouple age. I think in idle it goes up and down like 5°C, maybe less, don't know how would perform in some tasks like soldering, I believe slow. Made in japan, hard to find this stuff today, except china made.

#### ivca33

Joined Jun 24, 2019
12
yes I agree, especially now when i found cheap big piece of cooper for tips/cartridge heater holder on wooden handle, there will be some serious mass and I believe it will not be sensitive to tip heat loss, but i do need advice on one more thing.

I'm making this device with couple of reasons. Aside the fact that it should speed up my process, main reason is to not ruin project in one of the later phases, which already happened and it is not nice
Before, I was making this phase strictly mechanically, using friction to get heat, which is not the good way for softer materials.

With electric dimmer station I will get rid of the rough friction problem, but now there is instant burn/heat scrape problem. So I would like to have some top temp protection.
The best, most effective way is to add cheep on/off temperature regulator before dimmer. I can set it to like 150, and than play until I get on dimmer 100°C. It will be more a protection than a regulation.

I just don't know If it's allowed to connect this two devices? that is my question from beginning.

I love to make my own tools, there is a lot metal hand tools, precision tools, modded electric motors and inserts, but here are some from wood I made recently.

Long story short, I love quality, and i know it has price, but if I see I can get more if I made it by my own i will do it. I'm not cheap, but I don't like to overpay, hmm , that's why we all love forums and info shearing, right

Anyway, I will repeat myself,I hope here is someone who can answer me.
can I put "regulator/dimmer/speed controller" between "on/of relay temperature type regulator" and "cartridge heather" ?
Is it safe?

tnx guys

Joined Jul 18, 2013
21,182
I can see no problem, that is basically the way the iron I posted works.
Max.

#### MisterBill2

Joined Jan 23, 2018
6,660
How about a rest for the heated device that includes a dial thermometer like the ones used for checking food temperatures? Then you could see the starting temperature. OR even include such a thermometer in the heated device itself? That would give you the ability to know what you were doing and remove the dependence on instrumentation electronics. Not as modern or as slick, but really effective and not complicated. And for the price of a cheap electronic temperature sensor you can buy quite a few of those dial thermometers.

#### ivca33

Joined Jun 24, 2019
12
If you think on something like oven thermostat,

even though it is used a lot on similar devices, like irons for covering/sealing, it requires (at least I think) that thermostat is on the heating element or at least on housing of it. If you look at sensor it have some kind of hard wire. It is only to extend mount option like in oven but not to move once we choose position. So, already there I stop taking this option in consideration, lack of option to have compact and movable handle like with soldering iron, so I didn't even go further and search for accuracy, speed, feedback etc. to see how it is in these fields..... But I believe it is Ok ,

like I said it is used for some tools.

#### ivca33

Joined Jun 24, 2019
12
@MaxHeadRoom , thank you for final answer, also tnx other guys for help.

I have no more questions regard this, so other members can use thread freely if they need it, or it can be marked as solved.

cya , until my next question

Joined Jul 18, 2013
21,182
If you think on something like oven thermostat,
it requires (at least I think) that thermostat is on the heating element or at least on housing of it. ... But I believe it is Ok ,

like I said it is used for some tools.
The oven Bi-metal thermostat does not require to be near the heat source.
In fact there is a micro equivalent on the Picmicro site that shows a solid state equivalent.
The oven thermo uses the current through the device for control and the knob moves the thermo contact closer or further apart.
Max.

#### ivca33

Joined Jun 24, 2019
12
it doesn't but than it have this wire, I look to it and it is nichrome wire, which transfer heat to bi-metal, if I'm not mistaken.

This wire can't be put in cable together with heater wires, I mean it could but it would be stiff, and who knows prone to snap fast due cable banding and stuff. I know that similar thing my father have on stove for house heating, and it is quite stiff....

Am I missing something? maybe there is something softer to transfer heat, i don't know.

#### MisterBill2

Joined Jan 23, 2018
6,660
The oven Bi-metal thermostat does not require to be near the heat source.
In fact there is a micro equivalent on the Picmicro site that shows a solid state equivalent.
The oven thermo uses the current through the device for control and the knob moves the thermo contact closer or further apart.
Max.
Stoves and ovens use two different kinds of temperature controls. The more accurate type senses the temperature at some point where the temperature matters, the other type uses what amounts to a variable duty cycle blinker to vary the total power fed to a heater element. That is similar to adjusting the gas flow to a burner on a gas stove. It does not need to sense the temperature because it is only changing the delivered power. In my evaluation that sort of control is cheap junk, and it has a reputation for producing a lot of electrical noise.

#### MisterBill2

Joined Jan 23, 2018
6,660
it doesn't but than it have this wire, I look to it and it is nichrome wire, which transfer heat to bi-metal, if I'm not mistaken.

This wire can't be put in cable together with heater wires, I mean it could but it would be stiff, and who knows prone to snap fast due cable banding and stuff. I know that similar thing my father have on stove for house heating, and it is quite stiff....

Am I missing something? maybe there is something softer to transfer heat, i don't know.
Which post number are you referring to? This is getting confusing.