Rapido hotend Maximum Practical Flow Rate Test

More details
trianglelab.ne...

[@burakov]

Thank you for detailed pdf! I cannot get more than 26 mm3, extruder starts to slip. Both ABS and PLA

[@kiyosenl.3889]

Curious, whats the advantage of this over something like a volcano

[@morbus5726]

Lighter, better cooling, a lot more flow for the length, and a lot more flow overall. (This also has a volcano add on)

[@whatif8741]

The heating up time is way less too

[@art3m_t1mofeev]

I think the main advantage here are structural reinforcements in heatbreak area, which allows for very thin heatbreaks, as they are no loger bear any load. Also, heatblock, heating element and thermistor are one integrated unit now, which allows for better temperature control and more consistent flow overall.

[@SirSpence99]

Wow, what a massive load of false advertising. You advertise up to 75 cubic mm/s yet you need a 0.8 nozzle to get anywhere close to that. *No one* labels their hotend that way.

[@kevinaub]

yeah but it's still a valid claim though. I mean you'd have to be running crazy good speeds to max out your hotend on 0.4 mm nozzles. So the bottleneck for the hotend flow rate is in fact the machine setup. However, if you use a 0.8 mm nozzle you're really pushing the flowrate to the hotend's limit, not the machine's limit, which is a better way to rate a hotend TBH. I say this because I particularly print large models with a 0.6 nozzle on a RatRig VCore3 and even that maxes out the rapido at the speed that I print at. Remember speed is the machine's limitation. Open up to larger nozzles like 0.8 and not so much because you're trying to melt a bigger volumetric density. In fact, I'm about to try to change to a CHT Volcano nozzle with the Rapido and see if that manages to match my printers' speed so that the printer is as efficient as possible. For the nozzle sizes that I use I need an even faster melt rate, so 0.8mm nozzle at 100mms would be heavenly for me! For that I'm waiting for the Goliath(aka LSD) from VzBot to be released

[@SirSpence99]

@@kevinaub I can routinely print with a v6 and a 0.4 nozzle at 12 cubic mm/s and I have to run it slower than I would like because of the hotend. If I wanted to print at 20-30 cubic mm/s and didn't care about the nozzle size, I'd just go with a v6 and a 1.0-1.2mm nozzle. Except, here is the kicker, I want to print at 30-40 cubic mm/s *with* a 0.4 nozzle. Given that literally every other hotend is advertised using a 0.4 nozzle for measuring flow rate, yes, this *is* false advertising. Nozzle size has minimal impact on maximum usable flow rate. You get about 10% flow rate per .1mm above .4 I often print inner perimeters at 1.2mm widths, with a 0.4 nozzle and get excellent quality. I've managed that with a 0.3 nozzle on a v6. Sadly, the rapido is incredibly prone to clogging (also not advertised) and so a 0.4 nozzle is the *minimum* size you can use without serious problems. I've also found that it *can* get up to ~24 cubic mm/s with a 0.4 nozzle. Which means that the product doesn't meet my needs and was falsely advertised. The fact I had to go to their website, find their youtube channel, look for a specific video, then go and look in the comments and read a pdf listed in the comment in order to find the testing conditions means I will not recommend the rapido to anyone and will instead strongly encourage them to find a different hotend.

[@kevinaub]

@SirSpence there's absolutely no way a v6 can maintain 1.2mm nozzle printing at a higher rate than about 27mms(flow rate) regardless of the speed of the printer. at that nozzle size and flow rate of the v6 you'd have to run the printer extremely slow for the hotend to cope. it'll be melting more plastic but unless you can get a higher flow rate hotend like the rapido you won't be able to print faster than the max volumetric rate of the hotend

[@SirSpence99]

@@kevinaub A v6 maxes out at 15 cubic mm, 12 if for good quality. at 1.2mm widths, that means around 50mm/s travel speed. My gantry should be able to handle four times that without a problem. Thus, 30-60 cubic mm/s was my target. Imagine my surprise when the rapido can only do twice the v6. And no, I didn't run a 1.2mm nozzle, that was with a 0.4mm nozzle and set to 1.2mm widths... If you haven't messed with extrusion widths without changing your nozzle, you are missing one of the top three most useful settings to making quality prints. Your nozzle size affects three things above all else, layer heights, minimum extrusion width and likeliness to clog. I like to run my 0.4 nozzle at 1.2mm widths at a .1 layer height, which you can't do with a larger nozzle. It makes some amazing overhangs.

[@8bits955]

@@SirSpence99 if you are printing at 50mm/s travel speed at 1.2mm width and 0.1mm layer height, your volumetric flow rate is only at 6 cubic mm as per equation volumetric flow = speed * line width * layer height you are no where near the max of what v6 is capable let alone a rapido bro. Not to mention i highly doubt that is actually producing 1.2mm line width with a 0.4 nozzle unless you got one of these special nozzles with a massive flat surface at the tip. Not to mention this is not false advertising at all, get your definition of max volumetric flow rate right first.

[@leoetcheverry9685]

no info at all hear !!! this seller is so bad