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De Ranged

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I think the speed of print is, as you say, how quickly you can get the head to change direction without overshoot, but also how quickly you can feed the material, and that comes down to how quickly you can melt it all the way through. So I guess a thinner rod is better from that respect. 

Hard to describe without drawings or photos but in will try. If needs be I will do some sketches.

There are a few ways of doing it. For one clip you can try put it on the split line so there is no reverse draw. I did this once on a fitting that had the clip broken into 8 expanding segments. The cores overlapped each other to create a void behind the clips to give them room to expand if that makes any sense.

For a small clip we jump it. That is, you open the mould to remove the outer mould from the part then use a stripper plate to push the part off. As its plastic and still warm it will stretch over and return to size. A bit of an angle on the clip helps. 

Another way we have dont it is not to have the clip going all the way around. Just have 1 or 2 bits depending on size. For one bit you can have a section of the core which slides forwards with the ejection stroke, the part drops down slightly then gets swept off as you retract the ejection. For more than one you can use an up and away ejector pin. It's a pre engineered component which is bent so that as your ejection comes forwards it springs inwards. You cut your profile in it and mount them in the core. 

Or the ultimate which we have never used due to cost and being able to do the job cheaper ways, are collapsing cores. Again they are pre engineered components. You send a drawing to the manufacturer and they make them with the profile cut in for you. Then have a pin down the middle and as you retract it all the segments move in in 2 stages so that it all collapses in. 

Finally.you can make an unscrewer. You.get a core cut with a thread on that you want on your part, then cut the same pitch thread on the other end of the core. When you want to get it out the part you turn the core with a motor. And it winds itself out of the part and into the mould. 

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  • 4 weeks later...

Lol I discovered I hadn't submitted my reply..... do that all the time on messanger 

In short you have a very cool job Cynic-al.... the problem solving would be cool 

Well I finally got my printer..... from a second company and for $160 less than the first company, who asked to cancel the deal due to supply issues lol that worked out well for me 

PSDCwns.jpg

Surprisingly well packaged and with good instructions (unless your visually challanged lol) I had to stop assembling it and wait for daylight to read the manual and that was with my glasses. After I finished putting it together I decided to watch one of the Youtube videos on starting an Ender 3..... if your doing this watch the videos first lol I ended up going back and adjusted most of what I'd assembled, I followed the setup video and printed one of the files on a supplied SD card 

WpdJ14q.jpg

I'm impressed at how good it is straight out of the box, compared to the videos I've seen on Youtube, there are a few (I think they are called this...) artifacts early on in base layers of the print but the top 3/4's is real good no defects, there was some very light stringing off the tail and between the ears..... and when I took it out into the bright afternoon light I was able to see a bit of a pattern on the rounded surfaces.... I'm guessing a vibration coming through? But its that fine I stuggle to see it under artifical light, even the layers ontop of the head where its a very shallow curve you have to move the model around under artifical light to see 

LcOONLz.jpg

I'm guessing the artifacts early on were dust and debri in the bouden tube and extrustion head, I've got a few files from the file sharing sites for improvement parts so when I start printing them I'll find out. Only a few of the "improvement" parts have arrived so far (a double drive filiment roller, and the extention cables to move the controller)... I'll start fitting them when they are all here, till these are done I'll keep playing with the PLA (I want the insulation on the bed and an inclosure before I start to play with ABS)

Found out PLA is Hydroscopic (absorbs moisture from the air) and its level of moisture effects its printing qaulity so I'm trying to pick up an old broken beer fridge I can make into a dry storage.... just fit a 15-20watt fillament bulb in it that is on all the time and it will keep the inside of the fridge dry at about 30 degrees (I've done this in the past for welding rods lol) 

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Been playing around with the printer a little bit (35+ hrs of printing so far), one print I downloaded from thingiverse was 14hrs and still yet to have any issues..... still just playing with PLA

Some of what I've found so far 

The printer isn't as accurate as they claim lol been using a steering knob I designed as a test piece 

yGWpQG9.jpg

Love the colour, its interesting how it has effected the camera and no its not that bright 

3HpwxPN.jpg

I designed a lipped ring as an interface between the two parts and I've got 1.0mm of run out, on a 45mm dia part. I've found oddly the larger the layer height the more accurate it is so that leads me to think it maybe due to material flow, I've also noticed a correlation to temp of the extruder head. But I've been playing with different rolls of PLA (for the different colours) and different slicers and setting..... so I need to do some proper testing... I'm going to try doing some temperature towers on the 3 different filiments and see if there is any noticable difference 

On one pages or video's I watched prior to getting this, there was reference to burning/melting off the "strings" with a heat gun.... makes sense since the melting piont is low for PLA so I figured I'd have a go with one model that was particually bad lol (think I had too much heat at the extruder) 

Lv3wU0r.jpg

Hmm got rid of the stringing but to do it I blistered and distorted the surface lol 

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Thanks for those tips...... I've just had a bit of a look at both of those... both very interesting, I need to get printing in ABS because Acetone doesn't work on PLA, but will with chloroform.... haven't played with that stuff since I was at high school lol, I'm loving playing with plastic its, there is so much to learn 

searched out Clough42, very interesting..... haven't found the video your talking about got distracted lol this guy is very inventive 

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Hopeing to get hold of a buggered shop display fridge to use as an enclosure and storage... waiting to see how it goes at auction 
I haven't had the chance to properly play yet, but I've found its really handy for simple fix's 

nG8v57S.jpg

Dish washer shelf wheels (be interesting to see how the PLA holds up), the latest is a rack for all the spices in the pantry lol not really what I bought it for 

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I use PETG pretty much exclusively, generally only use PLA for prototypes.

PETG is almost as easy to print as PLA, doesn't smell during printing, doesn't need an enclosure and has almost as good a temperature range as ABS. It's also more flexible than PLA and less brittle. Most of the stuff I print gets used in vehicles so the extra temperature range of PETG copes well with that.

Through my volunteer work I designed and printed some devices for our local hospital and as part of that the infection control team had to approve the design and materials which included exposure to some pretty extreme cleaning products. The PETG version passed all the tests and was approved and is now in use on the wards.

The only trick to changing from PLA to PETG, other than the higher print temperatures, is to increase the Z offset by 0.1 - 0.2mm to prevent dragging on the previous layer.

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21 minutes ago, elbekko said:

PETG would always clog up the nozzle in my printer, no such problem with PLA. Probably just wrong settings, was just using the defaults provided by XYZ.

You need to ramp the temperature up, I'm printing at 240C but it can also depend on the nozzle size you're using, how good the hot end is (how good the heat break is) and print speed. I do tend to wind back the retraction distance in the slicer more than I would for PLA, my current slicer also has a "cruise" setting which, rather than retracting at the end of the line it stops feeding material for the last couple of mm which reduces stringing so less retraction needed. I'm using a bowden setup so retraction is always a bit tricky to get just right. 

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  • 3 months later...

been a while so here is some of the stuff I've learned.... if I'm wrong speak up lol this is from my own playing and with some problems lots of reading on the internet lol sometimes that isn't helpfull at all like in the case of PETG bed adhesion problem.... increase bed temp or run no heated bed lol

First off mods to the printer..... my goal is to eventually get this thing printing in ABS so ideal temps are are 240-270C for the head 90-100C for the bed and an enclosure temp of 60-70C  so I've headed my mods in this direction 
I've printed a few different mods (filament guides, clips etc) these were for me more about learning and as such I printed them in PLA since its the easiest stuff to print so all of these will go or get replaced when I have the enclosure sorted.... check out "thingiverse.com" there are heaps of mods and endless projects to print 

So I started off with the usual youtube recomended improvements so I got a "set" with all the recomendations (HD bed springs, rubber mounts for the X and Y stepper motors, signal filters for the stepper motors, and an alloy filament drive, cost me less than $20 delivered), none of it is worth bothering with lol 
The HD bed springs, they are too tall and to use them you need to move the Z stop up (reducing your available Z axis)..... so I decided to see how long I could go with the standard springs without leveling my bed (this is apprarently the issue you get due to soft springs), I'm over 200hrs of printing and I've only "had" to level my bed twice.... I can live with that inconvenance 
The rubber mounts for the steppers.... lol I haven't used them.... the stepper motor is mounted too far from the drive belt as it is, the motor is 30mm wide and there is 20mm of shaft to the center of the drive cog there is enough deflection already that the belt is rubbing on the far side of the cog.... and the recomendation is add another 6mm of leverage and mount the motor on rubber lol no
The signal filters they made a difference but not like you hear on youtube lol I keep the printer in another room...
The all metal drive for the filament.... I was too lazy to fit it and even with it banging away for hrs after I've repeatedly jamed the hot end (I'll explain later lol) it isn't showing signs of damage or wear and the tensioning spring is the same so I see no reason to fit it 

Now for what is worthwhile 
I've insulated the underside of the bed, the information I have from the forums and it matches what I've seen with my infra red themometer is that the Ender 3 has a max bed temp of 80 odd, it varies a bit now this could be due to how I'm measureing it IR themometers have issues with black objects and glass it seems the bed has gained 4.5-5 degrees with the insulation on the underside. The better bit it has done is the heat is holding for more of the bed now not just a 150x150mm patch in the middle 
https://www.aliexpress.com/item/32878669055.html?spm=a2g0s.9042311.0.0.27424c4dXGSXQQ

I replaced the bouden tube with a Capricon PTFE tube. This wasn't an issue till I started printing PETG (hot end @ 240C) I got a jam after I'd printed about 20hrs worth of parts, this wasn't caused by the bouden tube it was due to heat creep (I'll explain later) but it took alot of pulling to get the tube out of the hot end and when it finally came out the end of the tube was sort of burned and had allowed the molten plastic up the outside of the tube... glueing it to the heat sink, so even with the hotend @ 240C it didn't want to budge, I changed to the Capricon tube and in the run of jams after this had no issues getting the tube out, preheat the hotend, back the fitting holding the tube out and gentle tug and if your quick the PETG is still warm in the tube so you just pull the plug out easily 

Currently the printer is out of action, after a run of jams caused by heat creep..... this is where there isn't enough flow of plastic through the hot end for the temps it is running at and the heat creeps up into the base of the heat sink melting the filament in the heat sink, the extra surface area of the melted plastic against the heat sink transfers the heat out of the plastic, setting it as a block..... removing the bouden tube on the last jam has damaged the fitting at the top of the hot end enough that it doesn't want to slide down over the tube any more 
Given I really want more heat in the hot end to do ABS properly instead of fixing the fitting I've ordered a micro swiss all metal hotend.... not the cheapest option but it comes plug n play, I don't have to print new fan mounts etc, it has a nice dual roller direct drive (removes the issue of the bouden tube slop effecting retraction) and is available in stock in New Zealand (no 3 month wait for it to come from overseas lol)

lol thats enough for now.... I'm missing out on shed time..... more to follow 

 

 

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  • 9 months later...

I got the Ender 3v2 (very similar to the pro) and very impressed. 
Seems to print well out the box. 
Just doing pla. I got the stronger springs and the bl touch (tried manual bed levelling and decided I’d rather have one less thing to worry about).

Started with TinkerCad (most things are shapes) and gradually learning Fusion360.

Dimensionally very impressed, measure it draw it print it and it fits.  


I thought little toys only but very useful for small replacement parts or something you want to be just so.

Makes very pretty objects.

Got octoprint that was very plug and play. 
 

Now starting to look at Land Rover applications. There are some plastic pieces for defender on thingyverse.

 

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Good on ya, they are fun to play with 

I've just got my second printer a Ender 5 plus, I wanted it for the larger bed.... I haven't pulled it out of the box yet, its that big I'm setting it up in the workshop so I need to build an enclosure.... my workshop is too cold and drafty to print without one, I've got a couple of builder mates so I'm just waiting on them to get me some demo material I can build it out of 
As for the Ender 3 lol...... its currently parked up, after setting up the Direct Drive hotend I'd printed a few smaller items with random levels of success.... for example same print mulitle times, one works well enough but with rather visible layering, another would lift from the bed, another artifacts etc .....after joining the offical FB group for the Ender5 models I found out ultimatly it was a bad E step tune on the extruder motor...... and by changing heats etc I'd been bandaiding the problem 

So I need to plug my laptop back in and tune it.... but I keep getting distracted by other things lol 

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I got the creality enclosure for mine. They do a tent size one for the Ender 5 I think.  It’s good for the money.
 

Although the Ender 3 range have some budget bits on I think a lot of time has gone into making sure those budget bits work well together.  I think possibly like cars it’s difficult to upgrade them and maintain that balance. Not going to stop me though. :-). Let me know how the 5 goes. I am thinking I’ll send away for bigger pieces but I could well be tempted with a bigger one. Or get the Ender extender kits to super size the 3.

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I considered the tent inclusures, there are some good reviews on Youtube, they seem to work well as draft stoppers but not so good for heating.... ultimately I want to get to the stage I'm able to print Polycarbinate, ABS first and that requires an inclosure I can heat past 100C so my plan is to build towards that now.... part of the reason for the E5 ... it is possible to convert them into a core XYZ this means I can mount the stepper motors outside the enclosure so when I get past 100C I don't start cooking them  

The larger printers from what I'm seeing on FB seem to be let down by bed leveling.... when your talking a difference of 0.1mm in nozzle to bed height can mean the difference between a good print and an overnight mess of plastic spaghetti. Then you see some of these guys posting videos showing 0.4mm of bed warp due to heat..... I'm working on a rather creative option that might work lol..... will get onto that one when I get my tool box's back from Australia as I'm going to need every mm of the bed surface when I start printing the tool trays for that 

Dammit lol distracted again still haven't gotten to the shed and now its close to lunch time 

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