Emergency Part Repairs! (Extruder Frame)

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twicx
Posts: 105
Joined: Fri Jan 11, 2013 1:26 pm

Emergency Part Repairs! (Extruder Frame)

Post by twicx »

Hello folks,

So my printer's been very very idle for the last few weeks. I was having difficulty with the filament not feeding consistently. After further investigation with some help from felix, I discovered that it was most likely due to a fairly significant break in part of the extruder frame. It's the bit where the spring/screw goes through to the extruder arm to tighten up the grip on the filament: (I put a piece of paper behind it so it's a bit clearer)
Image

I've contacted felix about this, and although he has been a big help in trying to get this sorted, I think he's unavailable at the moment. After looking at this crack/break, I noticed that if the crack was just repaired, it can hold a tight enough grip on the bolt that I might just get away with printing a replacement part myself. The plan is to use a particularly strong glue that I occasionally use for some architecture work. I can then hold it in place with a small clamp while it dries (I'll give it a good few hours) and then reprint the extruder arm (hoepfuly.) The thing is, I need it VERY urgently, as I've university finals at the start of September. So, I've three questions to see if anyone can shed some light on things:

1. Any suggestions/tips on how I could repair this part?
2. Any alternative solutions to how I could put a consistently tight grip on the fillament given my current situation?
3. Recommended print settings should I get this up and running?

Any help would be amazing!

Hugues
Posts: 270
Joined: Thu Apr 04, 2013 5:36 pm

Post by Hugues »

where do you live ? I'm in Switzerland
i've printed that part some weeks ago and i did not use it because the original was not warped as i initially believed,
i can ship it to you if you want , just be sure it's the version you want,

or maybe someone with a printer on this forum lives nearby,

just PM me
image-26.jpeg
image-27.jpeg
Hugues
Regards from Switzerland

twicx
Posts: 105
Joined: Fri Jan 11, 2013 1:26 pm

Post by twicx »

I'm in Ireland. I might have to take you up on that, but I think it might be worth my while trying to glue it in the mean time. If I can get the glue to hold for the few hours it needs to print that, I'll save myself a lot of time and effort.

Hugues
Posts: 270
Joined: Thu Apr 04, 2013 5:36 pm

Post by Hugues »

Is it ABS or PLA ?
If its ABS, You could try acetone to glue the part back.

If PLA, maybe try to melt the plastic and join the parts.

On Google it seems cyanoacrylate glue works on PLA
Last edited by Hugues on Sat Aug 10, 2013 8:57 pm, edited 1 time in total.
Hugues
Regards from Switzerland

killejano
Posts: 92
Joined: Mon Apr 01, 2013 7:23 pm

Post by killejano »

Might be a good idea to dril two holes and grind a bit to get a zip tie to pull the extruder bolt down. This way you should be able to tension it enought to print a replacement

twicx
Posts: 105
Joined: Fri Jan 11, 2013 1:26 pm

Post by twicx »

Hugues wrote:Is it ABS or PLA ?
If its ABS, You could try acetone to glue the part back.

If PLA, maybe try to melt the plastic and join the parts.

On Google it seems cyanoacrylate glue works on PLA
It's the original part, so whatever that is (never thought to check that...)

Yeah I usually work with cyano, just cos it pretty much bonds everything to everything else (usually my fingers to the model I'm working on). The only thing is, they cyano I have is about a year old, and it doesn't seem to be curing too quick, so I might go down and get some more tomorrow.

On a separate note, my best quote regarding my experience of working with cyano is "shit guys, I've managed to superglue my fingernails to my fingers..."
killejano wrote:Might be a good idea to dril two holes and grind a bit to get a zip tie to pull the extruder bolt down. This way you should be able to tension it enought to print a replacement
This isn't a bad idea at all! I'm actually thinking that I might be able to use a tie just to go between the extruder arm and the frame on the far side, so I wouldn't even have to drill a hole. The whole extruder frame assembly is currently disassembled, so I can see what does and doesn't fit. Excellent suggestion though buddy! +1 pint for you.

twicx
Posts: 105
Joined: Fri Jan 11, 2013 1:26 pm

Post by twicx »

SUPRA-EXCELLENT-MEGA-PROGRESS!!

So, I found a little bottle of Cyanofix in one of my many many boxes of architectural miscelany, result. I glued up the cracks, held it in place with a clamp, made tea and watched a bit of tv. A good while later, things were looking good, so I began the great extruder reconstruction. Interestingly, along the way I noticed a few little issues which I tidied up. the other round-head screw that's on the underside of the extruder was a little loose, and I replaced the bearing on the extruder arm, as it was sticking a bit, and on closer inspection, was a bit worn.

Once it was all back together, I noticed the extruder motor skipping, so i retuned the pot in the electronics box. I heated up the fillament to 200, loaded it up, and did some test feeds. It took me a good 35 mins to work out just the right tension to put on the tightening spring. I just want to be careful so as not to put too much pressure on what's an obviously delicate part. Anyway, eventually....

THE LETTER X STANDS FOR FUCK-YEAH!
Image

Ok, so that measures about 2cm x 2cm x 0.5cm, but it's a print, on production/high density, with more than acceptable level of quality, given the situation.

It is, however, 12:50am over here, so there's no way I'm starting on the extruder frame replacement piece now. I'll do it first thing in the morning.

-

Now, on the relevant subject of repairs (not the first time i've had to repair the extruder arm!) I now find myself looking over parts of my printer for signs of wear and tear, or parts that are clearly under stress and strain. The plan as it stands is to get this frame printed, and pray that my printer survives till the end of my finals in a few weeks time. HOWEVER, I've noticed very concerning signs of wear/stress in a number of parts including the Z motor bracket, the Z-opto-vane thing (mine slightly wobbles up and down), and a tiny bit at the electronics box (where the screws go). So I do plan on making myself a little collection of whatever backup parts are available on the boards, although I know the Z motor bracket one isn't. I can see why Felix did some upgrades on the Z axis in general between versions 1.5 and versions 2, but I've a few things I think I'm going to have to do myself in september, such as a slightly longer threaded rod, a better coupling at the motor, and a better bracket at the motor (there's a little vertical wobble in mine that I just can't seem to get rid of).

Anyway, in conclusion, these are just the issues I've noticed with mine. I know there's many people on here who haven't had any problems with their printer at all. The thing is, when it works, it works very very very well, and I really am pleased with it. But I do seem to be having reliability issues. I'm just hoping that it's the kind of thing that once everything's sorted, I won't have many more problems.

twicx
Posts: 105
Joined: Fri Jan 11, 2013 1:26 pm

Post by twicx »

HOORAY!

My parts arrived today, and after a day of general maintenance (replace a few bearings, recalibrate the X,Y and Z) the printer is now running really really smoothly. The 2.0 extruder assembly seems to tighten up a few little issues, like the little notch to prevent the hot end from rotating, and the improved spring carriage. Very pleased with the new assembly.

So, I am happy to report that once again, I'm back printing. I'd even go as far to say the overall performance is greatly improved!

superhornet59
Posts: 60
Joined: Wed Apr 03, 2013 1:58 am

Post by superhornet59 »

Just to throw this out there, I've used Gorilla Glue on PLA with great success. It expands to fill all the little tiny voids between the parts (that's what ultimately matters for any adhesive), and it's got a tiny bit of flex so it isn't brittle enough to fail under shock loads. In any case, glad to hear your printer is running smoothly. Now that you know how much it sucks, take it from me, invest the time to print a spare of each part, or you'll be knocking yourself later if something goes wrong. I've been down that road... never again though.

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