tag:blogger.com,1999:blog-4339813531032979196.post7407842834247139212..comments2024-02-28T07:32:59.864+00:00Comments on HydraRaptor: Yet another quick heater hacknopheadhttp://www.blogger.com/profile/12801535866788103677noreply@blogger.comBlogger32125tag:blogger.com,1999:blog-4339813531032979196.post-53645331611244770532020-02-12T04:02:48.916+00:002020-02-12T04:02:48.916+00:00It looks like this is the origin for the ubiquitou...It looks like this is the origin for the ubiquitous MK# heater blocks, so thank you for your work. Jeffhttps://www.blogger.com/profile/18221610086908120438noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-55684243571306568072011-04-23T09:40:45.863+01:002011-04-23T09:40:45.863+01:00I moved on to a smaller resistor http://hydrarapto...I moved on to a smaller resistor http://hydraraptor.blogspot.com/2009/11/no-compromise-extruder.html and I have used those almost continuously for more than a year with no failures.nopheadhttps://www.blogger.com/profile/12801535866788103677noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-74431827914830099702011-04-23T08:04:06.758+01:002011-04-23T08:04:06.758+01:00How did those resistors hold up? Or did you just h...How did those resistors hold up? Or did you just hack a new system to do the next cool thing?BAShttps://www.blogger.com/profile/11712266694307971483noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-22635830752059080762011-02-23T22:23:45.372+00:002011-02-23T22:23:45.372+00:00i accidentally bought 6.8 k ohm instead of 6.8
po...i accidentally bought 6.8 k ohm instead of 6.8<br /><br />poop!Josh Petersonhttps://www.blogger.com/profile/17417272466422972132noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-90013468549652355782011-02-23T21:33:17.415+00:002011-02-23T21:33:17.415+00:00Yes a resistor connected across a power source wil...Yes a resistor connected across a power source will draw a current I = V/R and dissipate power P = V^2/R. If it doesn't get hot it either not connected, or the value of the resistor is too high for the voltage.nopheadhttps://www.blogger.com/profile/12801535866788103677noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-32704189038537331052011-02-23T21:16:17.879+00:002011-02-23T21:16:17.879+00:00newbie electronics question....
I am trying to ap...newbie electronics question....<br /><br />I am trying to apply this outside of reprap to heat something -- i've never built a reprap. what is the circuit like to power this resistor? <br /><br />the reason i ask is that i hooked one of these up to a variable dc power supply, with just the resistor between the leads, and it draws no current. therefore, it doesn't get hot. why is this? do you have to hook your heater up in series with one of the stepper motors or something in order for the circuit to do anything? perhaps there is some other problem, and my question doesn't make sense. should just a plain old resistor hooked up to a power supply draw current? let me know if i need to clarify.Josh Petersonhttps://www.blogger.com/profile/17417272466422972132noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-13866019004757401682010-12-12T20:36:46.155+00:002010-12-12T20:36:46.155+00:00"Maximum working temperature must not exceed ..."Maximum working temperature must not exceed 125 °C." so probably not.nopheadhttps://www.blogger.com/profile/12801535866788103677noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-13556910288593868902010-12-12T20:19:53.701+00:002010-12-12T20:19:53.701+00:00are these any good ?
http://elektronik-lavpris.dk...are these any good ? <br />http://elektronik-lavpris.dk/files/sup2/rch.pdfAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-55353126488230156162010-08-27T10:46:07.721+01:002010-08-27T10:46:07.721+01:00They are too long really, the shortest one is 44mm...They are too long really, the shortest one is 44mm. With a hot zone that long I think you would get more ooze.<br /><br />Also the hole is too small for a 6mm barrel and has a wide tolerance, so it would be hard to make good thermal contact. I think you would have to glue it on with a high temperature thermally conductive adhesive.nopheadhttps://www.blogger.com/profile/12801535866788103677noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-14591008526372395952010-08-27T10:28:26.373+01:002010-08-27T10:28:26.373+01:00I was looking through resistors on digikey to make...I was looking through resistors on digikey to make another heater, and I found some tubular resistors that look interesting. Here's an example: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=FVT25-3.0-ND<br /><br />If we could find one of these with the right dimensions and resistance, one of these could turn out to be the ideal off-the-shelf heater, just stick your barrel through it. I'm a little out of my depth with this, though, any thoughts?whosawhatsis?https://www.blogger.com/profile/12792264289634575186noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-38435837010278790052010-07-29T21:37:12.382+01:002010-07-29T21:37:12.382+01:00I made one and posted it on thingiverse here: http...I made one and posted it on thingiverse here: http://www.thingiverse.com/thing:3650<br /><br />If you want to make a <i>thing</i> for this, I'll take mine down and post my pics as a copy, or I can just change the license to one of your choosing.whosawhatsis?https://www.blogger.com/profile/12792264289634575186noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-17346936393574026332010-02-06T07:19:51.281+00:002010-02-06T07:19:51.281+00:00makes sense, thanks for the response.makes sense, thanks for the response.Christopherhttps://www.blogger.com/profile/05616284901075978521noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-24580284904703027352010-02-05T19:51:22.584+00:002010-02-05T19:51:22.584+00:00Wire wound resistors have some inductance because ...Wire wound resistors have some inductance because they are a coil, but it doesn't have a significant effect when used as a heater because the switching frequency is relatively low and the waveform is unimportant.<br /><br />At worse it may cause a bit of ringing on the switching waveform, but nothing compared to the noise you get from switching stepper motors for example, which are many orders of magnitude more inductive.<br /><br />I can be a problem in audio circuits though and wire would resistors are not recommended for sense resistors in chopper drives.nopheadhttps://www.blogger.com/profile/12801535866788103677noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-238959703338671452010-02-05T19:40:18.405+00:002010-02-05T19:40:18.405+00:00have you seen this?
http://dkc1.digikey.com/us/EN/...have you seen this?<br />http://dkc1.digikey.com/us/EN/tod/Riedon/WirewoundResistors_NoAudio/WirewoundResistors_NoAudio.html<br /><br />talks about wire-wound power resistor technologies vs thick filme, and etc.<br /><br />one point they made was about pulse and high-frequency conditions. They mention that it could act as a low-q inductor and may interfere with sensitive components.<br /><br />did you find any of this (noise) to be a problem? or because it's embedded in a hunk o metal maybe it doesn't end up mattering?Christopherhttps://www.blogger.com/profile/05616284901075978521noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-65871134701037634612009-12-16T13:07:26.472+00:002009-12-16T13:07:26.472+00:00The resistance is chosen to give an appropriate po...The resistance is chosen to give an appropriate power when connected to 12V. Power is (V^2)/R. 6.8R gives about 20W which has been about right for all my extruders. The duty cycle is about 80% to get 240C.<br /><br />The one in the article would be a safe bet. I used a smaller one to reduce the surface area and mass of the heater block, but I haven't run it for more than a about 15 hours yet.<br /><br />The smaller one is an RWM 4 x 10 which needs a 5.5mm hole and is about 12mm long. The enamel is very thin so take care to to scrap it off if the hole is too tight.nopheadhttps://www.blogger.com/profile/12801535866788103677noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-69480985662534783412009-12-16T10:44:25.203+00:002009-12-16T10:44:25.203+00:00Is it fair to say then, that your main design cons...Is it fair to say then, that your main design constraint when choosing an appropriate Vitreous Wirewound Resistor was the dimensions of the resistor? Was there any reason for choosing 6.8 Ohm rather than 1 ohm or 10 ohms?<br /><br />For my extruder, I just want to use a 32mm brass M6 barrel, as is used in the Reprap ThermoplastExtruder 2.0, I would like to mill the tip directly into the barrel, I then intend to add an M6 through tapped aluminium block on the end to house the vitreous resistor, and thermistor. Have you any recommendations as to which resistor I should use, or with which would be interesting to experiment with? what size resistor did you use in your latest extruder?Anonymoushttps://www.blogger.com/profile/17207320619551063718noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-73200675899167890742009-12-15T23:14:52.554+00:002009-12-15T23:14:52.554+00:00Yes you have to overdrive the resistor Watts wise ...Yes you have to overdrive the resistor Watts wise to get it hot enough but it is stil within its surface temperature rating. I have actually used a smaller resistor on my latest extruder and it seems to hold up well so far.nopheadhttps://www.blogger.com/profile/12801535866788103677noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-78529285500861229412009-12-15T16:57:39.136+00:002009-12-15T16:57:39.136+00:00I would like to make an extruder heater this way
...I would like to make an extruder heater this way<br /><br />RS now sell an 14W Vitreous Wirewound Resistor (RS order no 666-1588)<br /><br />Is this more suitable? or is the idea to push more power through the resistor than it can handle and thus overheatsAnonymoushttps://www.blogger.com/profile/17207320619551063718noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-41202810763409861582009-12-15T16:54:17.072+00:002009-12-15T16:54:17.072+00:00I would like to make an extruder this way.
RS now...I would like to make an extruder this way.<br /><br />RS now offer a 14W Vitreous Wirewound Resistor (RS order no 666-1588)<br /><br />Would this be more suitable? or is the idea to give it more power than it can handle and thus overheats?Anonymoushttps://www.blogger.com/profile/17207320619551063718noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-23142674764770205292009-09-14T20:25:56.698+01:002009-09-14T20:25:56.698+01:00The manufacturer's datasheet that I linked to ...The manufacturer's datasheet that I linked to says they can handle surface temperatures up to 450C.nopheadhttps://www.blogger.com/profile/12801535866788103677noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-19761335768484170872009-09-06T06:08:32.406+01:002009-09-06T06:08:32.406+01:00Hmm... The specs on that RS page says they are onl...Hmm... The specs on that RS page says they are only rated to 200 degrees C, am I missing something?Affydawghttps://www.blogger.com/profile/03537097503056502229noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-19866385040045767262009-01-21T16:36:00.000+00:002009-01-21T16:36:00.000+00:00You might want to try some copper slip.It is used ...You might want to try some copper slip.<BR/><BR/>It is used on car brake components and can comp with the high temperatures encountered in brake systems.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-17199052017040155102009-01-21T15:17:00.000+00:002009-01-21T15:17:00.000+00:00I have not had any problem with M6x1 threads in AL...I have not had any problem with M6x1 threads in AL but I have only started using them recently. I don't know what the alloy is because I buy it as offcuts on eBay and reuse things I have dismantled.<BR/><BR/>I generally use thermal paste or PTFE tape if it needs sealing so I expect they help to lubricate it.<BR/><BR/>Greenhouse accessories use AL nuts and bolts with a fairly course pitch and they can be undone, even after being exposed to the elements. At least I assume it is AL, could be zinc I suppose or a special alloy.nopheadhttps://www.blogger.com/profile/12801535866788103677noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-68739829925690103282009-01-21T14:58:00.000+00:002009-01-21T14:58:00.000+00:00Nop,Another great idea. I had no idea that resist...Nop,<BR/><BR/>Another great idea. I had no idea that resistors were available that worked to 450 deg C. <BR/><BR/>You wrote: <BR/>> ... make a separate AL barrel that screws in.<BR/><BR/>Al-to-Al threads can gall (rub material off on another surface) and become very hard to take apart without damage. That's why I used brass for my nozzle inserts. <BR/><BR/>If you get Al-Al threads to dis-assemble OK, please post what alloy(s?) of Al you're using.<BR/><BR/>-- LarryLarry_Phttps://www.blogger.com/profile/17543327228811365805noreply@blogger.comtag:blogger.com,1999:blog-4339813531032979196.post-26870895639202284782009-01-21T13:21:00.000+00:002009-01-21T13:21:00.000+00:00Hi Marauder, I measured and calculated the heat t...Hi Marauder,<BR/> I <A HREF="http://hydraraptor.blogspot.com/2007/09/equations-of-extrusion.html" REL="nofollow">measured and calculated</A> the heat to melt HDPE and it was about 2.8W. This heater has plenty of spare capacity to cope with that.<BR/><BR/>My current heater swings +-1C about the set point at about 0.5Hz so I don't think I have a problem with temperature control.nopheadhttps://www.blogger.com/profile/12801535866788103677noreply@blogger.com