My upgraded K40 Pro has died unfortunately. The original issue with it is that a small mouse had used the low voltage wires to build a new nest. I have replaced all wires, checked them but there is an additional problem, when I want to turn on the machine, the fuse blows right away.
I checked all connections again, everything is where it supposed to be, checked the circuit boards on issues but it all looks ok to me. I don’t know what else to do, I’m not an electronic technician and I don’t know what to do next. It’s a cheap K40 but upgraded with an adjustable laserhead, and airpump etc. It worked great with Lightburn. Having it fixed by a professional would probably cost me more than the machine is worth I’m affraid.
Any idea’s what I could do next? Throw it in the bin and look for another affortable (and slightly bigger) machine?
There is a quite big community around the K40s, so I guess you might find some help out there
I think, I’d first try to exchange the power supply. I guess, those are not that expensive. You could try to remove all the cables from the power supply and then plug it into the wall. If the fuse still blows, the power supply is the reason. Otherwise, it’s behind.
You can unplug the lps and probably most of the cable to the controller. The see if it takes out a fuse. If it does, then @misken is likely correct about a failing power supply.
If it does work you should check it’s voltages. This isn’t rocket science and we can help you…
Get a cat or a two?
I live in the countryside and those damn critters are a royal nuisance every winter.
It’s been getting progressively quite a bit worse since our latest cat passed onto the greener micing pastures a few years back and we haven’t gotten around finding a replacement, yet.
I can see that changing in the very near future…
As for the machine itself:
^This.
If the fuse doesn’t blow, plug in all the cables one by one, starting from the least significant ones, leaving the tube for the last.
Assuming of course that the PSU/LPS starts or can be forced to start without load, not all such PSU:s will.
If it was just You reading the advice it would probably be needless to mention it, but since we never know who may read these, the PSU obviously needs to be powered down when plugging in (and out) the cables.
I know next to nothing about the design of the various CO2 PSU:s and LPS:s, but it would strike me as an odd feature if there wasn’t separate fuses for low- and high voltage circuits.
Grouping everything behind one fuse would IMO be questionable engineering, no matter what the price target is supposed to be.
If You feel that it’s beyond reasonable cost or effort to get it repaired and don’t want to stay on the K40 route and leave it as spare parts donor, sell it to someone else for spare parts or to try to fix up, I’d assume that there’s a market for it.
I for one would definitely be unable to resist a project (not that I have even a slightest shortage of projects as is ) like that if one would appear near to me.
I live in the countryside as well and I don’t like cats , my wife didn’t want me to kill the mice so I got a bunch of mouse-traps so I can catch them and keep them alive. The only disadvantage is that I have to release them at least 3+ km’s away from the house.
I will try to disconnect the cables from the power supply and see what’s happening, I don’t think the Monport K40 plus (of pro) even has a fuse onboard but I will start disconnecting stuff. So if it’s just a quick fix, I will do it but this also might be the time to get one with a bigger work are. I’ll think about it.
Just disconnected the plugs from the power supply and that right away showed the problem. The connector to the controller board was all black and there is even a small puddle with melted stuff underneath. So I think that at least the power supply is gone and maybe also the control board…
Any advice on a replacement power supply? Are all power supplies the same for the K40?
I’m not overly fond of cats either, but I can put up with them as long as they do their job .
I do like dogs though, but unfortunately the ones like various schnauzers and terriers originally bred as rat-catchers tend to lose that skill unless their parents teach 'em.
And the chance of that happening is very slim these days, the puppies are sold way too early for that.
Understandable, quite a bit of more work that I for example would like to do, but as they say; “Happy Wife, Happy Life”.
The smallish (to my needs anyway) work area of the K40 was one of the reasons I decided to go diode route when I was choosing my first laser, so I do understand that desire perfectly.
You’re welcome.
Yep, there’s Your culprit, there’s been quite a serious short on those wires for that kind of damage to happen.
The pinout on Your pic differ a bit from those I found with a quick internet search, but unless there’s a hole in the PCB (or sometimes even if there is), it’s unlikely that the PSU is completely toast.
The controller even less likely.
Whether it’s feasible to DIY repair such a low cost PSU at the component level is entirely different matter and varies greatly case to case, but getting it repaired by a professional is pretty much guaranteed to be unfeasible.
As I dislike this modern throwaway culture with a passion, if You decide to replace the PSU I’d still suggest selling or giving it away to someone who tinkers with them.
Since I don’t own a K40, any advice I could give would be just parroting or links to searches or unknown to me product pages, so I won’t do that.
There should be a model number on the unit or on the PCB, that’s as good a place to start as any.
As are K40 discussion boards.
I’m also rather sure that someone in here has gone through more than one K40 PSU, and will chime in at some point.
Based on my limited research on the matter, they are not.
First of all, the pinouts and connectors seem to differ slightly so it’s either exactly the same PSU, or some rewiring and new connectors are required.
Since in this case You are able to wire the boards Yourself, those minor differences probably don’t matter at all.
But could be a dealbreaker to others.
There seem to be quite a few “upgrade” PSUs for K40 available also, but combing through those require to dig in deeper into the specs than I’m able to.
Just as with everything, the price may correlate to the quality/features of a product…or not.
Thanks Sam, I will check how much a new power supply plus control board will cost me, it will probably be around € 120 all together I think. The Monport control board is around € 60,-
, my wife didn’t want me to kill the mice so I got a bunch of mouse-traps so I can catch them and keep them alive. The only disadvantage is that I have to release them at least 3+ km’s away from the house.
