I know the "tap the centre hole of extrusion and drill a clearance hole through the neighbouring piece" is a popular assembly technique, but I have reservations about it. I don't particularly trust aluminum with threads, it's very soft and easy to strip with modest torque compared to even mild steel. And then fixing two members with a single screw under-constrains the joint, leaving the possibiliby JamesK - Reprappers
Quoteo_lampe I've built a self balancing robot with such a sensor and it regulates so fast, you don't see or hear it. I must put that on the todo list. Self-balancers have always seemed amazingly cool.by JamesK - General
QuoteIchabodVThere is quite a learning curve with these things. Oh, that's the truth for sure. It never ceases to amaze me how things I thought I understood keep turning out to be more complicated than I'd realised.by JamesK - General
Quotethe_digital_dentistOf course, who knows what it will do when you factor in a close proximity print... That seems to be the biggest issue with the designs I've been trying recently. They seem quite promising when you run them in clear space, but once they are operating in the confined space between the nozzle and the print it becomes much more difficult to get even coverage. My first attemptby JamesK - General
QuoteleadinglightsHaving said that, I am finding difficulty getting a ring of nozzles on my hotend so that they fit in the available space and put air where it is wanted. I've been having the same problem with a printed fan duct that I wanted to get close in to the nozzle, there just isn't much space between the heater block and the print. I was toying with the idea of making some long nozzles wby JamesK - General
OnShape is hard to beat for a free service. The only concern is if they ever go bust and all your designs disappear with their servers. Fingers crossed they continue to prosper...by JamesK - General
Ok, that gives us somewhere to focus There are a few things that you could check/try: - is the firmware configured to use PID control for the heatbed? PID gives tighter control of the bed temperature, and if the bed temperature is held steady it shouldn't flex much. The (common) alternative to PID control is called bang-bang which is a much less accurate method (intended for mains powered heateby JamesK - Printing
Ok, so it looks like there are a couple of problems, one causing the horizontal bands and another for the diagonal ones. The diagonal ones are likely to be related to the extruder, possibly an off-center drive gear. The horizontal banding might be related to the Z screws. Is there any sign that they are bent and pushing the X axis side to side as they rotate? Another possibility is the bed flexinby JamesK - Printing
Yes, no worry. We've all been there at some point Just didn't want you to think you were being ignored.by JamesK - Printing
Hi, welcome to the forum. It's difficult for people to give you relevant advice unless you provide plenty of information about your printer and how you are using it. Photos of the printer showing it's construction and type would help, along with the type of filament you are using, and the print settings such as speed, temperature, layer height and nozzle size for example. There's a page describby JamesK - Printing
Depending on your fan duct and fan, full speed may just be too much for a low power bed to handle. I use 50mm blower fans and rarely use more than 60%. I've just been working on some new fan ducts to bring the air jets closer to the nozzle and it looks like that may lead to a reduction in required fan speed, even though the newer ducts restrict the flow more than the previous ones (but get it clby JamesK - General
Working through the following calibration guide might be helpful in checking the printer's setup:by JamesK - General
QuoteDjDemonDI'm well and truly bitten by the 3D printing bug Yeah, that happens eh? I got sidetracked into making a better fan duct this weekend which turns out to be quite tricky to design. I'm about 8 iterations in and still not quite there, which was getting a bit frustrating until it occurred to me how long it would be taking if I didn't have a 3d printer...by JamesK - General
You are very lucky to have such resources to hand Take a look at DD's current build log ( ). In particular, making a tall coreXY is a very efficient way to increase the build volume as the heated build plate is one of the major costs of a large build. However, Z is the slowest axis to print in, so perhaps you don't want to go to extremes on the Z to XY ratio. Using the 12mm for XY would makeby JamesK - General
Excellent, I would very much like to follow the build. I tried printing Delrin (acetal/pom) and it has the worst warp of anything I have seen. I've been toying with building a small delta specifically to handle the high enclosure temperature that I think would help, so I'll very interested to see how you get on. There's a forum section for deltas that I guess would be the best place to post ( )by JamesK - General
That's really nice. As well as being ultra-compact it should also be very robust. I've been going through small fans quite fast and it's getting really frustrating. The bearings go, possibly as a result of the g-forces when the nozzle hits any curled up edges while the fans are running. Given I have four fans on the (dual extruder) carriage it would be great to get rid of them all. Edit: Ok, oneby JamesK - General
QuoteLoboCNC what about doing a sample print with holes in it at various heights and then insert the thermistors into the holes. Yes, I should have done that in the first place, thought I could cut corners I'll give it a go... ...ok, that was quite interesting. With the probes inside the model I was able to insert each one during the print. I waited for a couple of layers above each hole beforby JamesK - General
Oh, that's very cool. I hadn't really thought about how small you'd managed to make heat-break cooling area in your hotends, but now you point it out that looks excellent. Very nice work!by JamesK - General
QuoteLoboCNC The bed heated to the glass transition temp. of the plastic allows the lower layers to relax and form an orderly transition from the unshrunk layers closer to the bed to the shrunken layers further from the bed. That seems like a very reasonable idea. Given that abs isn't a very good thermal conductor I wasn't sure what sort of distances the temperature would fall off over, so I priby JamesK - General
To a first order, it doesn't. The thing that stops abs from warping is a higher ambient temperature so that the plastic doesn't shrink so much after cooling through glass temperature, hence heated enclosures. However, for a given amount of warp, increased bed adhesion (however you get it) reduces the chances of the part coming off the bed. And for parts that aren't too high, warm air from the bedby JamesK - General
Yes, if the bed is basically working but the firmware is being a bit over sensitive it would make sense to back off the limits a little. Which firmware are you using? When I switched from marlin to repetier firmware I got the impression that repetier's thermal management is a little better than Marlin's. The other thing to look carefully at is the design of the fan duct for the part cooling fan.by JamesK - General
Shame, that got quite a way through before the failure. The quality on those overhangs was looking excellent!by JamesK - General
If it's a pcb bed heater, it's normal to have problems holding 110C+ when using part cooling fans, but not being able to hold 60C suggests the heater isn't working properly. If it's a dual 12/24V bed, make sure it's correctly wired for 12V, two of the pads have to be shorted together. If it's correctly wired, measure the bed resistance to check it's in the normal range of about 1 to 1.5 Ohms.by JamesK - General
Yes, they are different beasts. The buck (and related buck-boost) converters are amazingly useful and these days fantastic value - back when I was getting started in electronics I would never have believed it if you told me a 90% efficient DC-DC converter would become available for a couple of bucks. The good news is that a 7805 regulator is only a few cents (although you'll probably have to buyby JamesK - Reprappers
QuoteI also had to go up with temperature, now 200° for PLA, but may have to go up far more because of short contact/melting time. For HighSpeed i guess ABS would be the better choice, but on the other side PLA has greater overhang capabilities because faster hardening and not bending up so fast. Yes, I increase the temperature with PLA for high speeds. I think PLA has the lowest viscosity of thby JamesK - General
QuoteCould do a part in under 20min with 3 perimeters and no infill. You should only need a single perimeter. A 0.7mm nozzle and 3 perimeters would be at least 2.1mm walls which is unnecessary for this model. What extrusion width did you use? With a 0.7mm nozzle I would suggest a layer height of 0.4mm and width of 1.1mm. Glad to see that you are trying it - the combination of fast delta motion wby JamesK - General
I've never managed to get that combine infill option to work well in any print. It's a shame, one of the things I was hoping to do with dual extrusion is to use a small nozzle for perimeters and a big one for infill, and only printing the infill every second or 3rd layer (imagine a 0.4mm nozzle for perimeters printing 0.2mm layers and a 1mm for the infill printing 0.6mm layers). It should reallyby JamesK - General
QuotePrinting 0.5mm layers instead of 0.2 means 2.5times faster. My 38min/2.5 = 15,2 minutes with my speed setting. This means you must have printed with faster speeds than my printer can do...on So if i havent made a math error, then its a fake! If you can post a video, the title is yours. Kolbi, I'm trying very hard to find positives in your contribution and make allowances both for translatby JamesK - General
Quotenebbian QuoteJamesK if anyone is interested. approx 36mm/s linear I need an emoticon with bigger eyes, actually popping out of my head! That filament will be racing through the extruder! There's no way in hell any of my hotends could keep up with that. I think you win, so far Ah, I may have phrased that badly. I didn't mean 36mm/s of filament input, I meant 36mm/s head speed. I'llby JamesK - General
Edit, sorry this was unintentionally vague, I keep forgetting that the forum contracts internet links. The following is a link to the Thingiverse 'make' page for my go at the test object: if anyone is interested.by JamesK - General