New to 3d printing with smartrap need some help

Hello all,

I have built the version 4.7 and have everything set up, but I'm having trouble extruding. I'm using this hot end with no luck hot end i'm using. Any help is apreciated.

Thanks,

Jonathan

Quote
duranza
Hello all,

I have built the version 4.7 and have everything set up, but I'm having trouble extruding. I'm using this hot end with no luck hot end i'm using. Any help is apreciated.

Thanks,

Jonathan

I am not really surprised. That hotend is not what you would call "top of the range" I would guess that it will over heat at the top end after a while, maybe a short while and cause jamming issues.
What temps are you running at, and exactly what problems are you experiencing? What kind of extruder are you using, is it the direct drive as per 4.7 model? How about the drive gear, what are you using for that?
The more info you can provide, the easier it will be to help you.

---

[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

I'm using an mk7 gear and a direct drive extruder like it calls out for. I have tried running from 180 to 210 with no difference. And you are right about the jamming. I have to clean it with a drill bit and jams if I stop printing. If you can call it printing. I have not been able to print anything but blobs. So it is safe to say that I need a J-head style one then?

Quote
duranza
I'm using an mk7 gear and a direct drive extruder like it calls out for. I have tried running from 180 to 210 with no difference. And you are right about the jamming. I have to clean it with a drill bit and jams if I stop printing. If you can call it printing. I have not been able to print anything but blobs. So it is safe to say that I need a J-head style one then?

I specialize in hotends and have been using a design for several years now that works great with PLA. It is not as cheap as a J-head lite, but it works fantastic.
I will be posting on my website the details of making one for those that can't spend the money to buy one.
It has several parts to it, and has been designed specifically to tackle the problems that PLA brings.
PLA is my preferred plastic for printing as it has some really good qualities,is stronger and stiffer than ABS, has a lower melting point, no bad smell, bio-degradable, none toxic, and not an oil bi-product.
One of its bad features is that it becomes very plastic (soft) in a hotend that is not designed properly, and that is what causes the jamming at the top of the hotend.

Another problem you may find is that if the hotend doesn't allow the flow of plastic to flow easily through the nozzle, you will experience problems with the extruder too. This could be in the form of the extruder knocking (loosing steps from being over driven) or it could cause grinding of the filament that either cuts through the filament, clogs the teeth of the driving wheel, or simply doesn't feed at all.
The teeth of the driving wheel are best I have found it they are very large rather than small fine teeth. Fine teeth tend to slip easily on the filament and grid away until the teeth have filled up with filament particles and then the wheel will slip on the filament instead of driving it. Large teeth tend to over come this problem.

Edited 1 time(s). Last edit at 06/06/2014 01:38AM by regpye.

---

[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

I've seen this hot end for sale and it seemed to good to be true. I guess it is. I think it's important that it's both cheap and works.

Edited 1 time(s). Last edit at 06/05/2014 11:44PM by goldenmongoose.

It is too good to be true. Do not buy. Unless you can use for the parts. Regpye, I am a cnc machinist, so I can make my own parts. I also have access to an electronics surplus store that has fans and heatsinks and stuff. I just wish I had the experience with this stuff, but I guess if you don't stumble you don't learn...

For the money, I don't think you can get a bigger bang for your $ that the Ohio Plastics J Head Light V2 The old V1's has the same jamming issue with PLA though a little vegi oil on the PLA helped. I'm running the V2 and it is doing a great job for me.

Yes you only get what you pay for, and I had to learn the hard way.
I live in a remote area in South Australia, and the distance between the small town I live in and the "Big Smoke" is too far, takes about 3.5 hours just to get there.
That lead me to having to learn myself and do as much for myself as possible and a good hotend was something that was just not available to me at my location and also there were not many designs around when I first started out.
Many trial and errors and I started to find out what works and what does not. Having a Diploma of Applied Design (2002) helped a lot, but it was still uncharted areas that had not been explored yet.
My only interest at that time was to produce a hotend that works for myself. I found that and now others are experiencing the same problems I was faced with some years ago.
As I build a lot of machines, I am now using CNC processes to make the parts, as hand machining is OK for one or two, but doing a number can be a long tiring job.



I have not marketed any hotends yet, I have given several away for others test, but I can't keep doing that because they do cost money which has come out of my pocket.
I will be releasing soon and I guess there will be some reports coming back from the volunteers that I have supplied hotends to in the near future.

Edited 1 time(s). Last edit at 06/06/2014 12:36AM by regpye.

---

[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

Quote
goldenmongoose
I've seen this hot end for sale and it seemed to good to be true. I guess it is. I think it's important that it's both cheap and works.

You can't be referring to my hotend, because it has never been on sale anywhere yet, it has only been supplied with a complete machine.
Which hotend are you referring too? I would be interested in seeing what else is available.

---

[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

regpye, cudos on the new hot end design. I wasn't refering to the performance of your hot end. But, it's easy to make an expensive hot end that works well with PLA. It's much harder to make an inexpensive hot end that works well with PLA. I saw you're hot end design and it looks cool. But, are there any source files available? I'm curious because it looks pretty long compared to most others. A standard J-head is about 2.5" and reg's is 4"?

Quote
duranza
It is too good to be true. Do not buy. Unless you can use for the parts. Regpye, I am a cnc machinist, so I can make my own parts. I also have access to an electronics surplus store that has fans and heatsinks and stuff. I just wish I had the experience with this stuff, but I guess if you don't stumble you don't learn...

Yes very true,and I guess I stumbled a lot to start with.
Some things I learnt were to stop the heat travelling up the shaft, if you can do that the main problems are gone.
Another problem is with the nozzle, it needs designing so it has a sealing land that mates with the shaft, mine are 118 degrees.
There are many things to consider that make the hotend either a great hotend or one that works or doesn't work.
Trial and error, lots of patience, time and money is the only way to really learn about them. It is quite interesting really,
I love working with these machines, there are so many things to experiment with and new ideas to try.
The SmartRap has all of these qualities and from what I have seen in this forum it is really an interesting project that many have now contributed to and the ideas just keep coming.

Edited 1 time(s). Last edit at 06/06/2014 01:42AM by regpye.

---

[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

Quote
goldenmongoose
regpye, cudos on the new hot end design. I wasn't refering to the performance of your hot end. But, it's easy to make an expensive hot end that works well with PLA. It's much harder to make an inexpensive hot end that works well with PLA. I saw you're hot end design and it looks cool. But, are there any source files available? I'm curious because it looks pretty long compared to most others. A standard J-head is about 2.5" and reg's is 4"?

No, mine is 2.75" or 65mm from tip of nozzle to the end of the cold end, so it is not too different from the standard J-head.
Mine also has a few more parts than the J-head, those are to stop the heat travel.

Source files will be available when I get time to put them up on my website.

---

[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

Quote
goldenmongoose
regpye, cudos on the new hot end design. I wasn't refering to the performance of your hot end. But, it's easy to make an expensive hot end that works well with PLA. It's much harder to make an inexpensive hot end that works well with PLA.

I am interested to know what you would call expensive? I haven't mentioned a price as yet, but I do know that expensive can also mean loss of time fixing a cheaper design, lost filament also adds up, and lost deadlines if you are printing parts for others, all make a cheaper hotend a very expensive one.
Sorry for steering this thread in another direction, but I think this is all relevant to what was asked in the first place, because new 3Ders need to know and learn about all these things and if we can all explore them together and pass on our experiences, we all benefit in some way, don't you think?

Edited 1 time(s). Last edit at 06/06/2014 01:49AM by regpye.

---

[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

Hey, I'm not against anyone here.

Thanks so much for everybody's input. This is the reason why I took on this project. It is open source and people help each other. I'm very hands on, and very good with cnc manufacturing (14 years exp) but thermodynamics took me by surprise. Eventually we all will stumble with the not such good ways of doing things and hopefully turns into a wiki/ reference for others not to make the same mistakes. I will post some pictures of my build later tonight. I can't wait to get printing so I can start customizing.

Thanks,

Jonathan

duranza, I have a $6.70 suggestion for you... Order J-Head Lite V2 Stainless Steel Barrel, Mount, PTFE Liner & Holder Insulation Kit and either replace the barrel in your current setup or transfer your parts to this... It does work well with PLA...

Oh cool.. I didn't see that they sold the parts.. I'll be buying this asap. Thanks...

Oh, if you move things over to the Jhead-Lite you'll also need This ($1.50), Sorry... or some form of heat sink...

Quote
madmike8
Oh, if you move things over to the Jhead-Lite you'll also need This ($1.50), Sorry... or some form of heat sink...

And this. Need that rockwool in between or the heatsink won't perform like it should. Order them all together and save shipping.

Edited 2 time(s). Last edit at 06/06/2014 04:49PM by markstephen.

Thanks Mark, I was thinking I missed something... Still pretty cheap working upgrade for his current parts...

Sure thing Mike. I found this out the hard way when with my V1. I didn't have any Kapton tape and "temporally" held the ceramic insulation on with wire. It started falling apart and once it was gone around the heatsink, I was getting jamming and heat up the barrel to the point I couldn't get more than a 20 minuet print out before the mounting arm got REAL soft... With a properly built V2 now on my machine, I can print without error for hours. I just did 2, 3+ hour prints back to back and my mounting arm never got warm. I printed up a couple of brackets for mounting my Dremel tool to the Z axis of my CNC router, part of an upgrade, refit project I have going on for the machine.

Mark

Ok, so I made this heat sink to use with the parts and I still get jamming. I can push the filament forcefully and it will extrude, but the stepper just kicks back. I'm just going to buy the j-head light and be done with it. I tryed to put the temperature to 230 but no help. just makes bubbling sounds.

Quote
duranza
Ok, so I made this heat sink to use with the parts and I still get jamming. I can push the filament forcefully and it will extrude, but the stepper just kicks back. I'm just going to buy the j-head light and be done with it. I tryed to put the temperature to 230 but no help. just makes bubbling sounds.

Increasing the temperature will actually make the situation worse.
Kick back from the extruder can be caused through over driving the stepper driver, too much force on the filament, jamming hotend, too little current on the stepper driver, or some obstruction in the system (rubbish in filament, blocked nozzle, etc)
Have you adjusted the current properly for your extruder?
Have you burnt out any rubbish that may be in the nozzle?(use a gas flame on the nozzle, don't get the brass red hot, wash in water and then look through and see if the hole is clear)

---

[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

The stepper is set up at 900ma of current and it sounds great feeding through the tube, but as soon as it reaches the tip it extrudes a bit and then it stops and jams. Could it be that is trying to extrude too fast? I calibrated it by using the lcd menu and extruding 1mm and measuring and adjusting. Is there a better way? Before trying to run with the new heatsink, I cleared the stainless 6mm threaded rod and heated up the tip until I could see through the .4 mm hole. This is so frustrating.

This is what my build looks like. Everything went smooth with the assembly.

Quote
duranza
The stepper is set up at 900ma of current and it sounds great feeding through the tube, but as soon as it reaches the tip it extrudes a bit and then it stops and jams. Could it be that is trying to extrude too fast? I calibrated it by using the lcd menu and extruding 1mm and measuring and adjusting. Is there a better way? Before trying to run with the new heatsink, I cleared the stainless 6mm threaded rod and heated up the tip until I could see through the .4 mm hole. This is so frustrating.

OK, lets try and help you out a bit.
Can you remove the nozzle easily so that the filament can be sent through by the extruder without the nozzle being attached at all?
If you can, then we can set the steps accurately and after the steps have been set, you can put the nozzle back again.

OK, so now you should have the nozzle removed.
Send a M302 code to the printer through Pronterface or whatever other way you communicate with the printer. This allows you to cold extrude.
Never use this with the nozzle attached or you could do some damage. You do not want the nozzle to be heated, so leave everything in the cold state.
You should now be able to send an extrude command to send out say 50mm of filament. but first just cut the filament off close to where the nozzle would normally be then send an extrude filament command for 50 or 100mm of filament, cut off and measure what came out. Make the adjustments to correct the steps needed and test again until you get the exact length for the steps you have set.

Next the stepper current. For this you need a volt meter,a multimeter should do fine. Set it to the 20 volt range or lower if it has one, so you are able to read around the 2 volts.
I have made a special set of probes for doing this job from another multimeter probe set. The positive I have made into a small screw driver so I can adjust the very small pot on the motor driver, use a piece of heat shrink to insulate anything but the very tip of this screwdriver.The negative lead I have added a patch lead from a development board, just a single wire with a small pin on the end. I plug this into any of the spare ground pin holes in anyone of the stepper driver sockets (they are all connected together, all are GRD)
Now when you go to adjust the pot you will automatically get the voltage reading as you adjust, you can do this with all the stepper drivers using the same setup.
A direct drive extruder needs full power, but not to be over powered or it will turn itself off and you will get knocking. If it is under powered you just wont get the drive to work properly.
To get the full amount of power you should set the voltage to read 1.2 volts, that will give you close to 2 amps output.Drop this down a fraction to 1.1 volts and you should be pretty right.
Your motor should not get hot if set correctly. Too much or too little will make your motor get warm, and also you will hear or feel the knocking.
Another tip is to put your fingers on the motor when it is working and you will be able to feel the knock if you can;t hear it.

The heatsink that you have made looks a bit long, you don't need it to be anywhere as long as that. The important part is to have a heat break close to the heater block, so the heat doesn't travel up above the heater block.

Edited 1 time(s). Last edit at 06/06/2014 10:59PM by regpye.

---

[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

Quote
duranza
This is what my build looks like. Everything went smooth with the assembly.

I see a problem, it could be one of the things causing you pain.
The Bowden tube should be a smooth curve from the extruder to the hotend. Any bends will add a VERY LOT to the fiction within the tube and can cause the problems that you are experiencing. You have multiple bends and I am sure that this will be at least one of the factors causing your problems. Try to straighten the tube out as much as possible and allow it to be free of the wiring that can also cause a drag on everything.

---

[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

Reg, where were you when I started getting into this stuff. Your a wealth of knowledge, and have some cool tricks. Needless to say I set my voltage the hard way. I'm gonna make one of these for the next one.

Ok. I have confirmed the steps per mm to be good. It is set in marlin at 91.23 steps per mm and it is right on. I did try to run at 20% feed rate and got some progress. It extruded some steady strands for about a minute then it started clicking/skipping steps again. I have verified that the temperature is within 1 degree of what it displays on the screen. I did also free up the bowden tube to let it be by itself.

Quote
duranza
Ok. I have confirmed the steps per mm to be good. It is set in marlin at 91.23 steps per mm and it is right on. I did try to run at 20% feed rate and got some progress. It extruded some steady strands for about a minute then it started clicking/skipping steps again. I have verified that the temperature is within 1 degree of what it displays on the screen. I did also free up the bowden tube to let it be by itself.

With the nozzle heated, are you able to push the filament through the hotend by hand? I would disconnect the Bowden to test this, leave a length of filament out so that you have something to hand feed.
What we are trying to do is verify that the hotend is actually working and is not the cause of the problem.
If that feed OK, then you know that the problem is possibly with the feeding system and not the actual hotend.(although you can still have a problem with the hotend after feeding along length through, that we have to find out when the rest has been checked)

---

[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci