<p>Is there any convention on how to mark an all metal hotend to distinguish it from a hotend with a PTFE tube in the heatbreak? Once assembled for a German Riprap 3D printer, they look exactly the same on the outside.   I'm trying to decide on a way of marking them to indicate the difference.</p>
<p>Hotend with heatsink
<a href="https://i.stack.imgur.com/ZljCB.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ZljCB.jpg" alt="enter image description here" /></a></p>
<p>Exposed part of heatbreak between heater block and heatsink
<a href="https://i.stack.imgur.com/GpQtt.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/GpQtt.jpg" alt="enter image description here" /></a></p>
<p>Easy to see PTFE tube on nozzle side of heatbreak (all metal hotend has an all metal heatbreak with no PTFE)
<a href="https://i.stack.imgur.com/VKfVG.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/VKfVG.jpg" alt="enter image description here" /></a></p>
<p>Even after removing heatsink, PTFE tube is difficult to see in heatbreak (all metal hotend has an all metal heatbreak with no PTFE)
<a href="https://i.stack.imgur.com/Injic.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Injic.jpg" alt="enter image description here" /></a></p>
<p>Nozzle end of all metal heatbreak
<a href="https://i.stack.imgur.com/31MYU.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/31MYU.jpg" alt="enter image description here" /></a></p>
<p>Heatsink end of all metal heatbreak
<a href="https://i.stack.imgur.com/srJZ2.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/srJZ2.jpg" alt="enter image description here" /></a></p>

[{'answer_id': 16567, 'author': 'Zeiss Ikon', 'author_id': 28508, 'author_profile': 'https://3dprinting.stackexchange.com/users/28508', 'pm_score': 3, 'selected': True, 'text': "<p>Given your heatbreaks are the same material and external dimensions, it seems that the most practical way to distinguish one from the other would be to mount the all metal heatbreaks in a heat sink that's anodized to some other color than natural aluminum -- red or blue, for instance.</p>\n<p>If you can't buy them that way, or already have plenty on hand, anodizing is fairly easy to do at home -- you need battery acid, a car battery (or heavy duty charger for one), and some strongly colored dye to apply after the anodize has established the oxide layer on the aluminum part.  There are many online references on how to proceed and how to stay safe while handling the acid.</p>\n<p>If you have machining capability, another option would be to make, say, a copper heat sink for the all metal heatbreak, while keeping the aluminum for the conventional one.</p>\n"}, {'answer_id': 16622, 'author': 'user3324888', 'author_id': 28554, 'author_profile': 'https://3dprinting.stackexchange.com/users/28554', 'pm_score': 0, 'selected': False, 'text': '<p>Usually, the neck of an all-metal heat break would be thinner (as it does not need to contain the PTFE tube, and making it overly thick would conduct heat unneccesarily). This may be observable when one loses track of what is where.\nIf one needs to see at a glance, I do not think there is a convention.</p>\n'}]
['https://3dprinting.stackexchange.com/questions/16566', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/15075/']