NEW BPS 3D Printer Extruder

30+hrs on a single print
https://www.youtube.com/watch?v=r8QAMmDFSks

Clean, effective, compact. I like it. I like it very much.

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Realizer- One who realizes dreams by making them a reality either by possibility or by completion. Also creating or renewing hopes of dreams.
"keep in mind, even the best printer can not print with the best filament if the user is the problem." -Ohmarinus

For sale? Website?

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Realizer- One who realizes dreams by making them a reality either by possibility or by completion. Also creating or renewing hopes of dreams.
"keep in mind, even the best printer can not print with the best filament if the user is the problem." -Ohmarinus

I don't see how the thermistor is retained from falling out, potential fire hazard if you don't rigidly affix the thermistor to the hot end.

Hi MrDoctorDIV, Yes it's for sale now. You can get this from ebay [www.ebay.com.au]
or from my facebook page [www.facebook.com]
I only have 16 of them on the first batch.
Cheers, Bill

Edited 1 time(s). Last edit at 07/11/2014 08:45PM by billsprototypestudio.

Hi A2, I have used Heatsink Compounds for the Thermistor and have printed hundreds hrs on it without any problem.
If you are worry about it, you can use some kapton tape to affix it.
Cheers, Bill

billsprototypestudio you should redesign your hot end with a mechanical thermistor retainer, what you and many other mfg of hot ends are doing is not safe.
Eventually Kapton tape will soften, and adhesion will be lost due to the heat, then the thermistor is free to fall out, either a melt down, or fire will ensue.

Any way to attach thermistor and heater besides tape?
[forums.reprap.org]



Fire Hazard
[forums.reprap.org]

A2, Thank you for bringing this up. I got a very simple solution just for you, all you need is just one paper clipe and some pliers, please see attached photos. It's not going to come out unless you use a plier to pull it out.
Hope you are happy with this solution.
Cheers, Bill

Edited 2 time(s). Last edit at 07/11/2014 11:38PM by billsprototypestudio.

Most people don't have your skills, strength, dexterity, control, or expertise to form things with the correct amount of interference, and of the correct geometry.

Tugging on the termistor leads to verify that the paper clip hack is intact is not advised, as the fine wire of the thermistor could fail. If there is a gap between the tag end of the wire and heater block the wire could work it's way out. Replacing the thermistor will be difficult.

Among many considerations, I prefer a solution that is mechanically simple to employ, uses quality, and appropriate materials, and is easy to test.

You have room between the two thermistor holes and the heater cartridge-well for a tapped hole, and you are already setup on that plane to machine holes. Could you fabricate from sheet metal a retaining plate/shield/cover, with a hole in it to pass the thermistor leads, and retain it with a bolt? It would cover the thermistor well completely, it is easily removed, and can be readily tested that it's screwed down tight.

Most hot end mfg don't have a robust solution to retain the thermistor. I think your taking steps in the right direction. I really don't want to see any one harmed, and I'm sure you don't either.

An engineered solution would entail a validation of the materials, and method of retention, longevity test, failure mode analysis, redundancy, a maintenance, and replacement protocol, etc., etc. I am not giving you advice or expert opinion.

Tks.

Edited 1 time(s). Last edit at 07/12/2014 01:42AM by A2.

Quote
A2
Any way to attach thermistor and heater besides tape?

Tape? What an awful kludge.

Thermistors should be glued in. With J-B Weld, high temperature silicone or, if 300 °C isn't sufficient, with ceramics like exhaust putty or fire cement. That's what professionals do, too. They just glue into a bolt to allow replacing the thermistor by replacing the bolt.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

@Traumflug:
I didn't suggest tape

I do agree with you that it should in addition being mechanically retained, incorporate a high temp bonding agent, maybe with muffler repair cement (Water Glass: Sodium Silicate), high temperature silicone, or a high temperature epoxy.

Quote
billsprototypestudio
If you are worry about it, you can use some kapton tape to affix it.

Here are all my links pertaining to screw-on thermistors:

Screw-on Thermistor M3 Stud, seller rp_one_labs [www.ebay.com]
Amico 0-500C Fork Terminal 6mm Screw Threaded Thermocouple K Type 1 Meters, seller uxcell [www.amazon.com]
2 pcs Thermistor in #6 Lug, 10K @ 25 C, J Curve, NTC, seller memotronics_llc. [www.ebay.com]

Edited 2 time(s). Last edit at 07/12/2014 08:57AM by A2.

I will try to do my best to satisfy my customers. Any one who wish to use the (Screw-on Thermistor M3 Stud) just let me know and I'll make the lower Thermistor hole to M3 size thread as to photo asttached.

I just want to update ebay link with active listing (link mentioned by A2 ran out).
Ebay link for M3 Stud thermistor

Our thermistor is currently installed on Witbox 3D printers and new Prusa i3 versions (products of bq company in Spain). History of thermistor reliability is about 1.5 years.
Max working temperature for prolonged periods is 250C.

Housing looks nicely machined, are you still selling these?

Edited 1 time(s). Last edit at 02/06/2016 01:42PM by MechaBits.

Quote
Traumflug

Quote
A2
Any way to attach thermistor and heater besides tape?

Tape? What an awful kludge.

Thermistors should be glued in. With J-B Weld, high temperature silicone or, if 300 °C isn't sufficient, with ceramics like exhaust putty or fire cement. That's what professionals do, too. They just glue into a bolt to allow replacing the thermistor by replacing the bolt.

TESTIFY!
...and it snaps to pieces of you look at it sideways.

I'm giving JBW Marine Weld its day in court, for both the thermistor and the heat plugs.