Dual V3 Head Not Ready for Prime Time

A forum dedicated to the stock LulzBot TAZ 3D Printer
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tetralite
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Dual V3 Head Not Ready for Prime Time

Post by tetralite » Tue Feb 13, 2018 2:55 am

BEWARE the Dual V3 head! Thumbs down!
I bought the Dual V3 head for my second Taz 6 and have nothing but regrets. Nozzle 2 has the known thermistor wonky connection problem, so temperatures are reported all over the map, causing wrong temperatures to be generated in the hot end. After 3 days of wondering why prints kept failing and temperature warnings kept halting prints, I finally noticed the reported temps on the LCD were hoping around like crazy, varying from 170º to 250ºC. No wonder the hot end was confused. So after wasting 3 days I decided to send the V3 back for a refund. Then I found out that the return policy at Lulzbot says they charge a 15% "restocking" fee, whatever the hell that means. I'm pissed because that means I will have paid $74.25 (15% of $495) plus insured return shipping of $25.50 for a total of $99.75 just to try out a defective piece of experimental crap that wasted three days of my time. They sent me an empty and worthless apology for their return policy, taking into account NO consideration that their print head was DEFECTIVE from the start. I wouldn't have the nerve to treat my customers like that, but the difference is I STAND BEHIND MY PRODUCTS 100% and Aleph Objects doesn't. Instead, they profit from defective returns. $100 down the drain! And three days of wasted time.

I have bought two Taz 6 printers and one Lulzbot Mini. My next printer will not be coming from Lulzbot as a result of their treatment.

It doesn't make matters any better that Cura 2.6.66 is by far the worst piece of software I've ever encountered. The GUI fails to refresh the screen practically every time you make a little change to the settings, that is, when it doesn't just totally crash.

I should have known better than to buy a newly developed and apparently under-tested piece of hardware before there's been time to work the bugs out.

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Orias
Aleph Objects | LulzBot
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Re: Dual V3 Head Not Ready for Prime Time

Post by Orias » Tue Feb 13, 2018 9:28 am

We're sorry your v3 was behaving like that. It's not normal. We've seen some reports of temperature fluctuations, and are looking closely at the thermistor, the thermistor crimping, and even updated firmware settings to drill down to the root cause.
We hope you try us again. Thank you for your understanding and patience, any deviation from our established return policies goes through our department leaders, who typically come in at 7 a.m. Mountain time. We have some good news for you in your inbox.

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tetralite
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Re: Dual V3 Head Not Ready for Prime Time

Post by tetralite » Tue Feb 13, 2018 11:56 pm

Thank you for waiving the "restocking" fee after I complained about it a couple times.

I may try a dual head again some time in the future, but after they have been tried and tested and revised a few times. I'm making production parts and really don't want to spend all my time experimenting with under-developed or defective equipment.

Aha
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Re: Dual V3 Head Not Ready for Prime Time

Post by Aha » Sun Feb 18, 2018 1:32 pm

That sucks that it took so long to figure out! It was either better or worse for me. I got mine friday night, worked on it all day yesterday, but all my prints kept failing within 20 minutes or so with the same error. So it was pretty easy for me to figure out that was the problem. Tech support suggested I recrimp the connectors or just squish them with needlenosed pliers. I had thought of stripping and soldering them in a bit better, but there's not really the length required for that. But pinching them a bit and putting them back in let me get some prints done and move on to the next problems. So I've done that.

I'll have to keep trying with all this to see if I agree with you or not. It seems like knowing the root cause of a problem for a while would let you go run some better quality control on them (I found my issue REALLY fast, and I don't think it happened in shipping). Then again, they had filament in them when they came so they probably ran a test print, so I don't know why it wasn't caught then.

I might just be more willing to put up with the abuse since getting even bad prints with faults going within a day or two is leaps and bounds above the other printers I've dealt with.

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tetralite
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Re: Dual V3 Head Not Ready for Prime Time

Post by tetralite » Mon Feb 19, 2018 6:25 pm

The thermistor that failed in the unit I had, had some kind of white potting compound (perhaps ceramic) around the leads coming out of the metal cylindrical housing of the thermistor. There was no way to crimp anything, as the thermistor's leads were potted into the thermistor's package. If yours was different, my guess would be that this was an attempted fix made prior to shipping the V3 to me. And when I pay $500 for something, I expect it to be in working condition and not have to repair it as the first step.

kcchen_00
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Re: Dual V3 Head Not Ready for Prime Time

Post by kcchen_00 » Tue Feb 20, 2018 1:00 am

It would have been nice if they adopted the E3D thermister cartridge with the connectors...

bot_nick
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Re: Dual V3 Head Not Ready for Prime Time

Post by bot_nick » Tue Feb 20, 2018 11:06 pm

There are connectors. I have some posts on my trials and tribulations with the V3 and thermal irregularity. The connector is in the loom between the sensor and the main head connector. I should have posted pics. I soldered the thermistor leads to the crimp and have had no sensor-related thermal problems since.

radensb
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Re: Dual V3 Head Not Ready for Prime Time

Post by radensb » Wed Feb 21, 2018 12:04 pm

I would just like to mention that the dual v3 unit i received about a month ago was finally installed last weekend and has worked great so far with the current FW available in Cura 2.6.69 (which I believe is 1.1.5.71). After calibrating the Z-offset, I was able to print the Impossible Gears demo without issue. I also tried some prints just using the E1 extruder and so far they have come out just as good as my single extruder. I will keep an eye on the temperature fluctuation issue, but so far I have not experienced it.

I have run prints via USB through CURA on my PC and through the current version Octoprint with this setup. Not that it really matters for the issue discussed above, but just to point out that the current state of things are working stable for me that I have to disagree with the statement "Not ready for Prime Time".

silent_ninja1
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Re: Dual V3 Head Not Ready for Prime Time

Post by silent_ninja1 » Thu Feb 22, 2018 8:39 am

radensb wrote:
Wed Feb 21, 2018 12:04 pm
I would just like to mention that the dual v3 unit i received about a month ago was finally installed last weekend and has worked great so far with the current FW available in Cura 2.6.69 (which I believe is 1.1.5.71). After calibrating the Z-offset, I was able to print the Impossible Gears demo without issue. I also tried some prints just using the E1 extruder and so far they have come out just as good as my single extruder. I will keep an eye on the temperature fluctuation issue, but so far I have not experienced it.

I have run prints via USB through CURA on my PC and through the current version Octoprint with this setup. Not that it really matters for the issue discussed above, but just to point out that the current state of things are working stable for me that I have to disagree with the statement "Not ready for Prime Time".
Between the loading difficulty (I may drill the top plastic piece of mine out to be a straight vertical load), issue with needing to feed before retracting filament, firmware issues weve seen to date, as well as the manufacturing QC issues, its fairly safe to say it was rushed to market to be on sale before the holidays. Things are getting better now, but those of us who got on board early still feel the pain of it.

radensb
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Re: Dual V3 Head Not Ready for Prime Time

Post by radensb » Thu Feb 22, 2018 8:47 pm

For the loading, I have found that if you gently bend the last 8" or so of filament so that you reverse the natural curl (so that the curl aligns with the tool head path to the hot end), cut the tip at an angle (as they suggest), and walk the filament in with the tensioner released and the screw backed out a turn or so from the guide setting, it works its way right into place without a struggle.

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