Flower-Class Corvette by king derelict - FINISHED - Bensworx Virtual Kit - 1/48 - a log for the less gifted

[king derelict]

3 minutes ago, mtaylor said:

Have you tried a Ouija board?  Sounds like that might work as well the manufacturers instructions/list.   I'll keep my fingers crossed it's just the filament but considering all the problems you had early, I'm beginning to wonder.....

Thanks Mark

I have been reading that there are a batch of bad motherboards out there that cause extrusion issues, binitial layer instability - makes me wonder. 😄

[king derelict]

I hope the digressions into the 3D printing problems are acceptable in a build log rather than just a focus on teh model itself. I wanted to try to capture what I am learning with the process of making the 3D prints and maybe showing the lessons and results as well as the creation of a model

This morning I found that the controls on the printer allow a set length of filament to be extruded through the nozzle. So if you set 100 mm and you only get 95 mm its under extruding. That was the sort of information I was looking for so I marked 100 mm on the filament and set it running. It only extruded 50mm! A repeat attempt gave the same result. That is much too far in error to be a factory calibration problem so I wondered if it was the filament possibly being too hard and slipping in the extruder so I got out another reel and this time I got 60 mm instead of a 100 mm. Out of curiosity I tried a brand new reel and got 70mm. The value for each reel seemed repeatable, I can't see anything wrong with the extruder but something is not right. I increased the e-steps (the ratio of stepper motor steps per mm extruded) and a print came out much better. I don't think this is a dependable fix so I have ordered an aluminium extruder upgrade set to replace the factory plastic one. I can only think the extruder gears are slipping and the relative hardness of the filament results in the different extrusion rates. With luck I can get the upgrade installed in the next few days and see how it works out. I might install a new nozzle at the same time. Hopefully the voodoo will return

Alan

 

[mtaylor]

It's appropriate do post those issues I feel.   They'll help others who follow your log.

 

Try a new nozzle first if you have one.  It's possible yours is clogged or something else happened to it.  The new extruder can be installed after the nozzle.  The old rule of thumb I was taught was "change only one thing at a time otherwise you'll never know what the problem was.".

[Nirvana]

I just gave a thumb to Mark's statement!

[king derelict]

On 11/19/2021 at 9:03 PM, mtaylor said:

It's appropriate do post those issues I feel.   They'll help others who follow your log.

 

Try a new nozzle first if you have one.  It's possible yours is clogged or something else happened to it.  The new extruder can be installed after the nozzle.  The old rule of thumb I was taught was "change only one thing at a time otherwise you'll never know what the problem was.".

Thanks Mark. I like to make one change at a time too and looking at the parts to change it doesn't impact teh nozzle so it will be left alone for the while

Alan

[king derelict]

A day for learning. The replacement aluminium extruder upgrade kit arrived. In typical Creality fashion the instructions were an illustration with no text but there is a good Creality video and it is not very difficult.

When I removed the original gear from the exruder I found the cause of many of my recent woes. The PLA filament is obviously quite tough stuff and it had chewed a groove in teh brass wheel removing the majority of the teeth and allowing teh filament to slip.

This explains the poor detail and poor structural integrity of some of the prints - especially the more delicate ones. Also when I checked the calibration of the stepper motor I found that for a 100 mm commanded extrusion I only got 90 mm. So the printer has been under extruding the whole time I have had it and I think that is why I have had so much trouble with the alignment to the print bed. With the nozzle under extruding the line of filament being put out is thinner and cooling faster so getting good adhesion to the bed is more difficult. I am amazed now watching the printer putting down solid lines which are well fused to their neighbours and not skipping lines as it fills in sections.

Its very encouraging to have found a solid reason for the problem and be able to effect a cure. The upgrade kit provides a brass replacement gear and I haven't seen a further upgrade to a harder material so I suspect this problem will come round again but at least i know the symptoms and the cause. I have invested in a pack of ten gears from Creality for $10.

The first prints are very promising so here are a few before and after photos.

The four inch gun shield (half)

And the piece that brought this all into focus - the life raft racks

Now I have to decide how far back to go with repeating prints to clean up their appearance. I had only started printing the detail parts so hopefully not too far.

Thanks for looking in. Hopefully the next entry will be a bit more boat like

Alan

 

[mtaylor]

Wow... what a difference.  Who would have thought it was the brass feed gear?  I hope you'll pop them a message about the brass gear wearing like that and that fast.  

[Nirvana]

1 hour ago, mtaylor said:

Wow... what a difference.  Who would have thought it was the brass feed gear?  I hope you'll pop them a message about the brass gear wearing like that and that fast.  

Mark, unfortunately it's a know issue. The brass gear in Creality printers (Chinese) are much softer than American/European made (gear I mean).

[gjdale]

Glad to hear you have found the source of your problems Alan, but not so glad to hear of the poor QC with material choice by the manufacturer. If the filament is that hard, maybe you should 3D print some replacements for the brass part!

[yvesvidal]

Alan,

 

What a difference that upgrade makes. And thank you for identifying and finding a solution to this problem for us all, Creality Ender 3 users.

Although mine is not as damaged as yours, I will definitely consider that upgrade on my printer.

 

Yves

[king derelict]

17 hours ago, mtaylor said:

Wow... what a difference.  Who would have thought it was the brass feed gear?  I hope you'll pop them a message about the brass gear wearing like that and that fast.  

Hi Mark

I was surprised that it has already worn smooth in about four months. It has done some pretty heavy printing though. With all the initial problems i probably printed  the equivalent of two hulls to get good prints. The disappointment is that in the extruder upgrade you just get the same brass gear instead of a hardened one> creality seems to prefer selling you bags of ten replacement gears instead.

Alan

[king derelict]

15 hours ago, Nirvana said:

Mark, unfortunately it's a know issue. The brass gear in Creality printers (Chinese) are much softer than American/European made (gear I mean).

I did find a third party selling stainless gears but they got horrible reviews for poor teeth profiles and off centre bores that I didn't give them a try. One reviewer stated that out of ten two were useable.

Alan

[mtaylor]

I did find out that brass can be tempered which is probably what this needs.  However, finding an oven to get that hot is a problem.

 

https://sciencing.com/determine-copper-real-10511.html  Scroll down and you'll instructions.  

[king derelict]

13 hours ago, gjdale said:

Glad to hear you have found the source of your problems Alan, but not so glad to hear of the poor QC with material choice by the manufacturer. If the filament is that hard, maybe you should 3D print some replacements for the brass part!

Thanks Grant

The Ender is a great machine for the price. It seems to be Crealitys business plan to ship an "entry level" machine and then have a huge range of upgrades to support it. Being originally supplied as a kit it is amenable to being pulled apart and rebuilt which is nice. The upgrades are generally not expensive .  The lack of an upgraded gear is a bit annoying though. They do sell a complete new extruder but I'll see how the new gear holds up now that I'm not banging out 30 hour hull part prints back to back.

Alan

[king derelict]

4 minutes ago, mtaylor said:

I did find out that brass can be tempered which is probably what this needs.  However, finding an oven to get that hot is a problem.

 

https://sciencing.com/determine-copper-real-10511.html  Scroll down and you'll instructions.  

Thanks Mark

I think my oven is more suited to the turkey on Thursday

Alan

[king derelict]

The printer has been on duty through the day reliably turning out replacement parts. A last "before and after" shows the aft bandstand showing the poor quality of the earlier attempt that I was resigning myself to using. A set of bollards and cleats has now printed successfully 

 

 

I hope to continue printing out parts in between holiday activity for the next few days.

Thanks for looking and for the encouragement

Alan

[lmagna]

Much higher resolution parts Alan. The better reliability and quality of parts should make this a much more rewarding build for you.  For what it is worth I don't think the brass feed wheel was your fault. You have been having problems getting quality prints right from the start. 

Edited November 24, 2021 by lmagna

[mtaylor]

Wow... that is an improvement.  Getting the upgrade bits probably helped a lot also.  Congrats.   I hope things keep going well.

[Old Collingwood]

Looking really good now  - what a difference  - so pleased for you mate.

 

OC.

[gjdale]

Hard to believe those parts were created by the same machine! Well done Alan - your perseverance has certainly paid off.

[yvesvidal]

Alan,

 

You have been officially promoted to Creality Ender V2 Field Support Manager !!!!!

WOW, what a difference in printing.

 

Yves

[Canute]

Alan, that's a quantum leap in the appearance of your parts. Well done.

[king derelict]

22 hours ago, lmagna said:

Much higher resolution parts Alan. The better reliability and quality of parts should make this a much more rewarding build for you.  For what it is worth I don't think the brass feed wheel was your fault. You have been having problems getting quality prints right from the start. 

Thanks Lou

Its great to see decent quality parts building up on teh print bed now

Alan

[king derelict]

21 hours ago, mtaylor said:

Wow... that is an improvement.  Getting the upgrade bits probably helped a lot also.  Congrats.   I hope things keep going well.

Thank You Mark

As an engineer I do much better with a tangible problem that I can find a solution to. It was frustrating flailing around not knowing what direction to go 

Have a great day tomorrow

Alan

[king derelict]

14 hours ago, gjdale said:

Hard to believe those parts were created by the same machine! Well done Alan - your perseverance has certainly paid off.

Thanks Grant

I was getting very close to dumping the Ender and giving up on teh corvette

Alan

[king derelict]

11 hours ago, yvesvidal said:

Alan,

 

You have been officially promoted to Creality Ender V2 Field Support Manager !!!!!

WOW, what a difference in printing.

 

Yves

Thank you very much Yves. I'll wear the badge with pride but I'm hoping I don't have to do too much more to keep it. I'm looking forward to knocking out good prints for a while.

Alan

[king derelict]

7 hours ago, Canute said:

Alan, that's a quantum leap in the appearance of your parts. Well done.

Many Thanks OC

Its good to be able to print the smaller deck fittings and see a useable result.

Alan 

[liteflight]

On 11/24/2021 at 10:52 AM, mtaylor said:

I did find out that brass can be tempered which is probably what this needs.  However, finding an oven to get that hot is a problem.

 

https://sciencing.com/determine-copper-real-10511.html  Scroll down and you'll instructions

 

Just to be clear, tempering is reducing hardness, generally in favour of toughness.  And reducing hardness of the brass drive roller is probably not what is required here.

The process described in the link is indeed softening the brass (or copper) to its softest state, even if I would describe that as annealing.

 

Rolling the drive teeth into the drive roller after machining will have work hardened the brass considerably and I would expect that to be the condition that gives the longest life propelling the PLA.

[liteflight]

Alan

 

Many thanks for your blog;  I am learning a lot of the things that (I think) I need to know about 3D printing.

 

Your "catch" of the filament roller is an example of getting to the root of a problem, after fire-fighting all the effects seperately

 

Very instructive blog, very impressive model

 

thanks,

andrew

[king derelict]

12 hours ago, liteflight said:

Alan

 

Many thanks for your blog;  I am learning a lot of the things that (I think) I need to know about 3D printing.

 

Your "catch" of the filament roller is an example of getting to the root of a problem, after fire-fighting all the effects seperately

 

Very instructive blog, very impressive model

 

thanks,

andrew

Thank you, Andrew, I'm glad you have found it useful. My intention was to try to share lessons as I learnt from my mistakes.

Out of the chaos I have developed a bed levelling routine that works for me and which I check regularly. As a result of the extruder gear issue, I will be checking the filament extrusion rate if prints start to lose quality. I'm trying to knock down the unknowns in printing.

Alan