Fried RAMBO??? Thankfully not...

[Sheaffer]

OK....I'm stupid. I was trying to remove a nozzle from the hot end (it was covered with PLA so I had it actively heating). Somehow the wrench i was using arced with the hot end wiring -- the rambo board died immediately. No LEDs light. I check the 15 amp fuse and that actually looks OK. I see there are also two small ceramic fuses on the board, however I have no idea how to tell if they failed (which would be great) or if I just fried the board completely. Anyone know the part number for the little ceramic fuses on digikey or mouser? Any other Ideas?

***UPDATE. I swapped the small ceramic fuses...the board works!!!

I found the following part on digikey: F1641CT-ND which I believe is the equivalent of 0448005.MR from the RAMBo manual. I ordered a 5 since I'm still stupid

Any other thoughts?

[Windshadow]

you can get the tiny 5a quick blow directly fro seemecnc too
http://www.seemecnc.com/products/5-amp- ... -for-rambo" onclick="window.open(this.href);return false;
[img]http://cdn.shopify.com/s/files/1/0276/2 ... 1452798201[/img]

[Sheaffer]

Thanks, Windshadow...I should have ordered from SeeMeCNC.

BTW...here's an Idea for SeeMeCNC...after I started using my printer heavily, I ordered a bunch of "spare" parts (a few of everything I figured would wear out eventually). Naturally one of the things I didn't order was fuses. It would be great if SeeMeCNC had some sort of package of spare parts that they could put together based on their experience. There is nothing I hate worse than having to wait a week to get a $1.00 part that is keeping me from printing (which is exactly where I am now). Just my two cents.

[geneb]

Do. Not. Work. On. Printer. With. Power. On.

EVER.



g.

[Sheaffer]

Do. Not. Work. On. Printer. With. Power. On.

EVER.



g.

Aww...what fun is that??

[IMBoring25]

There's not as much exposed conductive stuff on it to accidentally short, but the E3D is supposed to have its nozzle tightened at temperature. Not a lot of way around it for that setup.

[Sheaffer]

Below is an image of the nozzle which was the root cause of the issue. I printed about half kilo of PLA to get to this point. Unfortunately I was printing some very tall / thin structures (vertical axis windmill blades) which failed a number of times. The extruded PLA adhered to the nozzle and surrounding aluminum hot end structure. There was so much PLA adhered to the nozzle it was impossible to get a wrench on it (which is why I was actively heating the hot end in hopes of softening the adhered crap when I popped the fuse).

Now that everything is cold, I was able to disassemble the hot end (I'm getting good at this now ). Then it actually took me the better part of 30 minutes to carve off the PLA just so I could remove the nozzle

So other than not being stupid, are there any ideas as to how I can prevent a re-occurrence in the future?

http://i.imgur.com/cypIz0Q.jpg

[Windshadow]

I have been wiping off the hot nozzle before and after each print with a scrap of old rough leather belt and then right before I print after doing a short purge of plastic,I rub the nozzle with the smooth side of the belt it seems to help a lot and keep the build up down but so far I am only printing ABS so i don't know how well this works with other filaments

[geneb]

There's not as much exposed conductive stuff on it to accidentally short, but the E3D is supposed to have its nozzle tightened at temperature. Not a lot of way around it for that setup.

Wanna bet? Prepare tools, heat about 10C over target, smack the power switch to off and then tighten.

You could make it easier by mounting the E3D upside down (nozzle pointing up) and then invert all three carriages. Easy access that way.

Working on a hot end or any other electrical components with the power on is about as bright as trying to change the fan belt on a running engine. Yeah, you might get away with it once, but you've got to be lucky EVERY. SINGLE. TIME. Murphy only has to get lucky /once/.

g.

[geneb]

I have been wiping off the hot nozzle before and after each print with a scrap of old rough leather belt and then right before I print after doing a short purge of plastic,I rub the nozzle with the smooth side of the belt it seems to help a lot and keep the build up down but so far I am only printing ABS so i don't know how well this works with other filaments

You'd be surprised at how well a washcloth works for that. You can get packs of 'em at wally world pretty cheap and when they get packed with plastic boogers, you just toss it.

g.

[barry99705]

There's not as much exposed conductive stuff on it to accidentally short, but the E3D is supposed to have its nozzle tightened at temperature. Not a lot of way around it for that setup.

Wanna bet? Prepare tools, heat about 10C over target, smack the power switch to off and then tighten.

You could make it easier by mounting the E3D upside down (nozzle pointing up) and then invert all three carriages. Easy access that way.

Working on a hot end or any other electrical components with the power on is about as bright as trying to change the fan belt on a running engine. Yeah, you might get away with it once, but you've got to be lucky EVERY. SINGLE. TIME. Murphy only has to get lucky /once/.

g.

Well, you can get unlucky a couple times, just depends on how many fingers you need to hold the belt.

[Sheaffer]

So, anyway...while I still have all my fingers...and since I have little interest in purchasing cleaning towels with or without boogers...can anyone suggest a method to keep the nozzle clean(er) when using PLA?

The issue I have is that some of my print jobs are many hours long and often finish (or fail) overnight or while I'm at work. So the hot end is no longer hot and the PLA has completely hardened by the time I can address the problem.

I get that I can re-heat the hot end, but even then it is a goopy mess and is still really difficult to clean ... it is, after all, HOT with or without the power on

I will try using a piece of scrap leather after re-heating and powering off as suggested earlier, but it feels like I shouldn't have to clean the nozzle constantly or replace a nozzle after only a week or so of printing. Any ideas?

[barry99705]

I just scrape off the biggest pieces, when hot. I use the spatula that came with the printer for this.

[nitewatchman]

So, anyway...while I still have all my fingers...and since I have little interest in purchasing cleaning towels with or without boogers...can anyone suggest a method to keep the nozzle clean(er) when using PLA?

The issue I have is that some of my print jobs are many hours long and often finish (or fail) overnight or while I'm at work. So the hot end is no longer hot and the PLA has completely hardened by the time I can address the problem.

I get that I can re-heat the hot end, but even then it is a goopy mess and is still really difficult to clean ... it is, after all, HOT with or without the power on

I will try using a piece of scrap leather after re-heating and powering off as suggested earlier, but it feels like I shouldn't have to clean the nozzle constantly or replace a nozzle after only a week or so of printing. Any ideas?

I heat to temperature + a bit, kill the power and scrub down with a brass bristle brush from Woodcraft.

gary

[geneb]

You might check to make sure where the source of the goop is coming from - you may need to tighten the nozzle a bit if it's leaking.

g.

[Eric]

Someone had to mention changing belts while the engine was running:

[youtube]http://www.youtube.com/watch?v=BQhfcdQf1QA[/youtube]

I've rebuilt a couple VW engines in my history, but I no longer owned any by the time I saw this video. So no, I haven't tried it.

[geneb]

I'll be damned. Ok, replace "fan belt" with "serpentine belt".

g.

[barry99705]

Someone had to mention changing belts while the engine was running:

[youtube]http://www.youtube.com/watch?v=BQhfcdQf1QA[/youtube]

I've rebuilt a couple VW engines in my history, but I no longer owned any by the time I saw this video. So no, I haven't tried it.

[img]https://cdn.shopify.com/s/files/1/0032/ ... 1447800021[/img]

[Sheaffer]

Thanks everyone for the ideas...fuses arrived today and I will re-assemble the printer in the next day or so. I'll try the leather and brass brush ideas and will be sure the nozzle is tight. And...thanks for brightening a frustrating situation with a bit of humor (loved the VW belt change video).

[nitewatchman]

You might check to make sure where the source of the goop is coming from - you may need to tighten the nozzle a bit if it's leaking.

g.

Mine is just miscellaneous boogers.