regulated vs unregulated power supplies for "log vapes"

[Hippie Dickie]

"get rid of"

i guess that's where a PWM power supply is "better", in that it creates the needed voltage by time-slicing the current. So if the MOSFET has low internal resistance and is driven into the right operating zone, it stays cool. At least mine does.

 

[hazy]

Yes PWM is the way to go, particularly for a simple job like heating an element where a clean signal is not required. These cheap tattoo power supplies use a switchmode section to get the mains voltage down to about 20V, then use a simple linear regulator (LM317) to adjust the voltage. It's a bit old school. I'm yet to find a cheap all-PWM power supply with built in voltage display. I'm thinking of making one myself.

 

[Rick]

Just want to pop in and say thank you. Everybody who participated in this thread has and continues to help me get my VVPS going as it should.
I am more and more convinced every day that a log vape with a VV PS with digital readout is like apple pie and cheese. Just gotta go together.
I am always shocked at how long it takes me to "get it" in Zapville. I think we are getting close to getting it right now, thanks to so much help from FC and FC members.

I am getting my VV from these folks. http://www.tattoomachineequipment.com/tattoo-power-supplies Ours is the Stealth model but as you can see they have other choices at good prices. More bells and whistles and colors. The best deal from us will be to get one with a CRZ order. Because of shipping, time, etc, I do not think our stand alone VV price will be as good as you can get. So we will be offering the power cord kit, custom made for this type of VVPS with the standard log vape plug on the end. Nice 16 gauge wire, not kinky. These PSs need the switch in the left port which we will also provide.(one short piece of 1/4" round metal of some sort)

So get your VVPS wherever, then just order the power cord kit from us or make your own and you are good to go. Some of the pricier ones have ten turn knobs for very precise voltage adjustment. I can get the one we use to move in 1/4 volt or less increments. Voltage readout is to the hundredth of a volt. They seem to be reading about 1/4 volt high from actual voltage measured on the ohmmeter.
Thanks again all. More on my thread as time permits.

 

[hazy]

All the best with your latest venture Rick. Don't worry, it took me a while to "get it" too. I kind of knew a couple of years ago that my PD needed a variable power supply, but I just didn't get around to doing anything about it. There were also certain people at the time dismissing the idea, which didn't help either. It's a shame because I think it has been a bit of set back for the log vape community. I'm glad that's all behind us and we can now move on to better things. I just want to see log vape owners get the most out of their investment

 

[OhTheAgony]

My variable PSU started making a buzzing noise this weekend. It only does it under load and only above 12V or so, but it is annoying enough for me to stop using it. It sounds like the sound a capacitor makes just before it bursts, so it's probably safer to stop using it anyways. I've contacted the ebay seller if there is a warranty policy for these, but I don't have my hopes up since I probably voided the the warranty when opening it up to switch the fan off. What to do what to do. I might as well see if I can isolate the buzzing part and swap it out myself. Do you have any other advice perhaps Haze?

 

[hazy]

I think you are doing all you can. Capacitors are usually the weakest part in a power supply, I've had to replace them on a motherboard and in monitors. They didn't make any noise though, they just suddenly shat themselves. If there's the slightest hint of anything bulging or leaking then it would be worth replacing the cap. In a way it's good that there is some noise to help you isolate the problem. Maybe the cooling fan was necessary after all? That would be a bit disappointing considering you are using it nowhere near its rated maximum. If you do get it fixed then maybe switch the fan back on, but you can reduce its voltage so that it spins more slowly so that you won't hear it. Even a small amount of air movement can make a big difference to the cooling.

 

[OhTheAgony]

I don't think the lack of a working fan caused it to be honest. I kept a close eye on it for a while and it didn't get really warm in there at the load I've used, perhaps 40 to 45 degrees Celsius at most after hours of use. I didn't check the temperature of the actual components yet though, I'll do another test run later on.

It would become unusable to me when I have to use it with the fan anyways, the noise just drives me crazy. I could try swapping it out for a silent low rpm one perhaps, but it's a smaller size (50mm I believe) and I don't think there are any really quiet fans made in this size. I could probably get a silent 500rpm 120mm fan in there somehow if I had to though. I've tried turning the rpm's down (I use these, you can use several of them in a row) on the original fan, but it doesn't come on anymore under 6V and it still makes to much noise at the rpm's it's at at that voltage.

I hope I can save it anyway, it's been really nice to use otherwise.

For the moment I'm back to my unregulated 13,8V with the little dimmer switch. Even though the voltage is changing constantly on that one it still works pretty good luckily.

 

[hazy]

Those tiny fans are horrible, I can understand you not wanting to use it. I've used similar voltage reducers but I make them myself, although I've only used them with 80mm and 120mm fans. Good luck with tracking down the problem. Keep us posted on how things turn out.

On a side note, you might want to get a small 15V power supply (that's just an example, you might find a better/cheaper one) to use with your dimmer switch. They're quite cheap and can come in handy at times like this. They're also more portable than a large power supply

 

[OhTheAgony]

I think I've narrowed it down to one of these (there are two of them in my PSU. different brand btw, pic is just an example).

But it's pretty hard to be sure just by ear. Everything looks normal in there otherwise, no bulging capacitors unfortunately. Shouldn't I be able to feel the guilty part vibrating when I touch it with a screw driver if it makes a buzzing sound though? Because I could detect non of that.

Good idea btw, getting something regulated to go with the dimmer. Could have saved me some time figuring this one out, lol. I was looking for something like that locally but strange enough they only seem to stock 12V or lower here. I found that really odd. Imagine a whole wall filled with power supplies yet everything just stopped at 12V somehow

 

[djonkoman]

I think the higher ones are mostly used for laptops

 

[hazy]

I don't bother trying to buy things like power supplies locally, the first place I look is online. I don't think there is a lot of demand for them. There's plenty from places like ebay though, and much cheaper than they would probably cost around here. It's a bit of a pain waiting two weeks for it to arrive though...

I don't know if you can detect any buzzing by touching the cap, I don't have any experience with hearing noise coming from them. Maybe get something like a toilet roll tube and listen through that. If you don't mind doing a bit of soldering then there's no harm replacing the two large caps. Make sure you use the same capacitance value, and the same or higher voltage value, although the higher voltage one will be physically larger so it might not fit. Also, they have a temperature rating of something like 85 or 105, try to get the higher value which would hopefully be a bit more robust.

 

[OhTheAgony]

I prefer to buy locally if I can because of easy returns when there's a defect, but also to save shipping costs if it's a bigger/heavier item. Mostly to save time though, I hate waiting on international orders.

But, uhmm, when I woke up this morning I realized my PSU started buzzing just a day or so before my UD blew up. Perhaps I should check it again with something else attached to it, lol.

Fingers crossed

 

[OhTheAgony]

Well, I feel pretty dumb now

There's nothing wrong with my beloved variable PSU


I'm running my Solo of it on 8,5V right now, that thing draws over 2 amps when heating from cold.

 

[hazy]

So where did the noise come from?

 

[OhTheAgony]

I suspect it was one of the smaller coils that was resonating, one of them is located right next to the capacitor I was looking at at first. I can only guess though. I can't replicate it since the UD has passed away for good now. Good thing I hadn't send it in for warranty yet, lol. I've been using it every day with my Solo since then. Can't wait to have another log in the house again though.

 

[Frederick McGuire]

What do you guys think of this tattoo power supply?
http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=230668982714
I put an offer of $10 for it, which is worth the risk if it turns out to be crappy, but it looks like all I'll have to do is close the foot pedal switch, and make a UD power cord for it

 

[OhTheAgony]

It's hard to tell from the outside Fred. It could be good, or it could be the same technology as in the one Bwade got. Your safest bet would be to get the same one Hazy got (I looked for a link but couldn't find it, I'm sure he can post it again though) as it has been tested for your kind of use, unless the possibility of a little moding doesn't frighten you.

 

[Frederick McGuire]

Haha, I'm down for a bit of modding if necessary
I picked up 2 of them for $25
I'm gonna have 1 I leave at a friends place so I can take my logs on excursions

 

[u bwade wunner]

hey fredirick.best of luck with the new psus

it will work if you close the footpedal switch circuit.just short the cicuit either externally in a microphone plug or do it inside with a little wire and solder like i did.

you may need to beef up the heatsink on the regulator too inside if the voltage starts jumping about.simple enough job.after the fixup Mine runs day and night with no issues.

just a little word of warning.these tattoo units can run to 17v, some of them anyway.excessive temps may torch the element in you re log.I set my supply to 17v by accident when cleaning my area.It was glowing red when I noticed it I quickly shut the unit down and removed and checked the element and noticed the ceramic coating was flaking.when i scratched the flaking to see what the problem was,the element almost snapped in half .I quickly popped it back in and fired it up and all is good.I have ordered a new element to replace it.

I am making a log out of tassie oak.that will be cool when its finished.small and easy to hold and made with Oz wood.its been fun looking for all the parts Jeez!!

I would not like to be without my log even for a day or two

 

[OhTheAgony]

Yay, good thing you got a HI, Bwade!

Good thinking Fred, did you get them already?

 

[Frederick McGuire]

Nah, still waiting.
I wouldn't expect them for another week or so.

 

[u bwade wunner]

Yay, good thing you got a HI, Bwade!

Yes Oth,stoked she still works even with the severely cracked element.next week I should have fitted a new element to her.

Just saw this as well for anyone who is not up to soldering cables for a tattoo pwr supply

Thank you Rick.Innovation and inspiration as always

Tattoo power supply cable for logs

 

[Frederick McGuire]

Ok, so today I went out and got the supplies to make my power cord for my UD.
I've assembled the cable, but I seem to have a dead spot in my jack.

My VVPS has a led to indicate when the "pedal"is being pressed.
I made 1 plug shorted within itself so that it will be always on.
I plugged in the UD, and 5 mins later te heater core was still cool to the touch, so I unplugged the shorted plug, and plugged in the UD to that port.
The LED started blinking on and off if I jiggled the plug in the UD, basically sideways pressure will make it connect.
So it's basically unusable at the moment.

Does anyone have any ideas as to why it might be doing this?
And how I could fix it?
I pulled the plug out of the UD, and jiggled it a bit, and the led didn't come on, so it's not a short in the connector.

I just tried it in my CRZ, and my mystery log vape, and try both connect fine, so it looks like its an issue with the UD female plug.
I guess I'll have to contact Dave.

Edit:
Is it ok to crank the voltage to say 15v for a minute or 2 to get the log up to temp a bit quicker?
I know it'll vary depending on the vape, but is there a sorta general rule I should have in mind while playing around with the voltage?

 

[u bwade wunner]

hey fred

seems you might have a problem with your e dog

Is it ok to crank the voltage to say 15v for a minute or 2 to get the log up to temp a bit quicker?

the higher the voltage on your'e psu the more pressure you are putting on the logs element. id say try and keep the temps a tad lower.12.5 -14v max and that should be short term.long term keep it at 12v or lower or you risk overcooking the element.It is the one weakness of all logs.

the UD, from what i know is pretty much a sealed unit and will have to be returned to Dave if you cook the element. .Putting the element under 15v will put more pressure on the element.Long term I should imagine it might cook the element fry it.short term 15v should be ok.I run my hi 24/7 so i leave her at 12v all the time.I learned the hard way .luckily i figured out how to change the element in the Hi. Now I keep it simple the log stays at 12v.

i would nt personally go beyond 13.5-14v mark and thats during heat up.run it at 12v or even lower if its on all the time.I can vape at 11.5v then move the temps up 12v,12.5,13v for a hotter vape before returning it to 11v for essential oils.

best of luck.I hope you get to the bottom of youre trouble and its not a return trip to Dave

 

[Frederick McGuire]

Thanks for the info.
I've got a 12v supply, and that runs a bit too cool for my CRZ And UD.
I figure I'll use that one for leaving one of them on 24/7, and use the VVPS when I'm having a sesh.

I'll make sure to stay under 14v for now, once I find my sweet spot, would it be ok to leave the log at that voltage for a moderately extended period of time?
(think falling asleep with it on voltage X, and turning it down when I wake up.)
So probably like 18 hours max.

I figured over powering it to speed up heatuptimes would be a nono, but it can't hurt to ask

I noticed that the plug is a bit recessed in the UD.
Maybe getting a longer connector will serve me better

Also, again, I know it'll depend on the log, but roughly how long will a given log take to adjust to a new voltage?
Is it dial it up, and hit it straight away, wait 5 mins, 15 mins?