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Discuss any sort of mechanical stuff here: positioning systems, gears, extruding methods, etc.
Re: I don't think Marlin is optimally coded.. and here's why - 10 years ago
QuoteThe landscape of 32-bit boards is even a lot more fragmented, so it's unlikely we see a cheapo one soon. However the market for the generic arduino boards is much larger, so we already see cheap Due clones. Eventually it seems likely that a clone Due +shield +lcd setup will come to dominate the cost sensitive part of the printer market.by JamesK - Reprappers
Re: Optimizing CAD designs for strength and filament consumption? - 10 years ago
Ah, excellent, now we have something to get our teeth into. 0.5 Kg of mass at the tip sounds like quite a lot to move around for the size of the part. (Sounds like a fun project!) To support the static load at the tip, the vertical dimension of the beam is going to be key, so for that your original model of a thinned beam makes sense - I and T shape beams being classical for cantilevered supportby JamesK - Printing
Re: 1 Meter bot project - 10 years ago
Best internship ever? I hope you enjoy this opportunity, and I look forward to following your progress.by JamesK - General
Re: X-Axis Endstop not working?? - 10 years ago
The endstop direction (1 vs -1) has to match both the physical location of your endstop and the location on the RAMPS that you plug it into. Sounds like you have it plugged into the XMAX position. If the endstop is on the left as you look at the printer from the front, then you need to swap it over to XMIN and set the direction back to -1. If that doesn't seem to fit your situation, perhaps you cby JamesK - Printing
Re: clogging issues with red PLA from RepRapper Tech - 10 years ago
E3D is a British company. You can order direct, or they have a list of resellers on their website:by JamesK - Printing
Re: Optimizing CAD designs for strength and filament consumption? - 10 years ago
Surely you can't talk about strengthening the part without specifying the loads that it will be subjected to?by JamesK - Printing
Re: I don't think Marlin is optimally coded.. and here's why - 10 years ago
So you know about teacup right? There are plenty of choices, so you can pick one that suits. My best guess is that it isn't worth the effort of optimizing Marlin just as the the world is moving to 32 bit.by JamesK - Reprappers
Re: Prusa i3 Hephestos+ printbed issue - 10 years ago
One more thing to check, if you are using Marlin there's a configuration option for reducing power to the bed that would probably confuse the meter: // This sets the max power delivered to the bed, and replaces the HEATER_BED_DUTY_CYCLE_DIVIDER option. // all forms of bed control obey this (PID, bang-bang, bang-bang with hysteresis) // setting this to anything other than 255 enables a form of PWby JamesK - Printing
Re: Prusa i3 Hephestos+ printbed issue - 10 years ago
Really? Wow, I would have put money on that not being the case. I was just looking at your photos and the bed wires look pretty reasonable in gauge. Is there any sign of the ramps board over heating near the connectors? I'm wondering if there's a high resistance at one of the connectors. The other possibility is a bad mosfet that isn't turning fully on, in which case you'd expect the green heatsiby JamesK - Printing
Re: Prusa i3 Hephestos+ printbed issue - 10 years ago
There's a switch on the side of the PSU to select the input voltage, it sounds like you have it set for 240 when you are running it on 110. If that's not the case, check the voltage at the output terminals of the psu - it should be close to 12V under load. If you have 12V at the psu and 6 at the heat bed you have a problem with your wires (but it doesn't seem likely as to drop that much voltage tby JamesK - Printing
Re: Prusa i3 Hephestos+ printbed issue - 10 years ago
As Itchytweed suggested, time to get back to basics and Ohms law. Can you measure the resistance of the heatbed and the voltage at the bed terminals when the heater is on? From that we will have a better idea of what's going on. You also said that you were getting a 12/24V 30A power supply, which doesn't quite make sense - can you post a link? And a photo of the connections to the heatbed would bby JamesK - Printing
Re: Print Bed Glass - Avoid Bull Clips - 11 years ago
I like the sound of homing Z to max, and doing Z first. Not sure why that isn't the standard setup.by JamesK - Printing
Re: Screw assortment - 11 years ago
Boltdepot, mrmetric and McMaster are all USA only I think. I have similar problems finding good sources for metal stock - most of the good places either won't ship international, or the shipping is astronomical.by JamesK - Reprappers
Re: NEW: SinapTec AT328.02 is a 3D FDM printer controller board of ultra low cost, Based on Arduino Nano - 11 years ago
Not everyone wants to take their chances with the cheap mega/ramps clones. You could build one of these and be completely confident about the quality of every part. It's just an alternative, and options are goodby JamesK - General
Re: Odd layer displacement - 11 years ago
Heh, it's hard to resist when you have parts lying around like that. I'm currently working on a build that's based on the Prusa i3 layout, but making up my own frame. I'm trying to tell myself that I only need one printer, but there are a lot of things about this build that keep making me wonder what it would be like if it was different. I'm very much drawn to a core-XY layout with the bed movingby JamesK - Printing
Re: Odd layer displacement - 11 years ago
I'm only using them for Z. If you use them on X & Y you need to go to more expensive versions with reduced back-lash. It's possible, but not that common for 3d-printing (but the norm for cnc milling where the forces are much larger). Glad to hear you get the alignment sorted out.by JamesK - Printing
Re: Odd layer displacement - 11 years ago
Some of the i3s come with 8mm leadscrews from the start. I would think that some people have added them later as an upgrade - perhaps someone will chime in with what would be needed. I bought cheap 8mm leadscrews for my build and they look good to me, but I may just have been lucky.by JamesK - Printing
Re: Odd layer displacement - 11 years ago
What sort of threaded rods are they, standard m5 or leadscrew? m5 will wear quite easily, but it's cheap enough to replace. Leadscrews are normally pretty hard and the brass nuts are somewhat self lubricating.They are also made quite loose so that they have some play in the radial direction. The Z threaded rods pushing the head around is a pretty common problem, it's one of the causes of "Z wobblby JamesK - Printing
Re: Odd layer displacement - 11 years ago
Ah cool - lucky guess then Is there enough play in the mounting holes to re-center the motors under the screws? You'd want to loosen the screws, bring the Z axis down to the bottom to force the motors into the right place and then re-tighten the screws. I'm not familiar with the layout, it might be a bit tricky to tighten all 4 with the Z axis down, but if you can get a couple of them it will prby JamesK - Printing
Re: Odd layer displacement - 11 years ago
OK, so for an i3 style of printer I think you'd want to check for mechanical interference at the bottom of the Z travel pushing the gantry off center. Perhaps the Z screws/motors are slightly off and tighten up in the last part of the Z travel? You could try lowering the head to Z=0, putting a set square on the bed, registered with the x smooth rods, and then raise and lower the Z axis a little -by JamesK - Printing
Re: Ways to extend wiring? - 11 years ago
Quotedavedavedave quick question about gauges. so I know there are many different wire gauges but what I want to know is what are the downsides to using a 14 gauge wire on something like a nema17 or cooling fans? so pretty much, are there negatives to using say, 12 or 14 gauge wires on something that doesn't require such a big wire? thanks Not a whole lot of downsides, particularly if the part iby JamesK - General
Re: Odd layer displacement - 11 years ago
Hi, and welcome to the forum. I think you're probably going to have to give us a bit more information for people to be able to help you. The sort of printer you are using would be a good startby JamesK - Printing
Re: Prusa I3 Z axis problem - 11 years ago
Quoteo_lampe Quotewolfend I don't believe Olaf is correct. As you can see in the picture, when the Y-endstop is triggered, the extruder Y position will be at 0, which is min. In the picture, the green arrow represents the 0,0,0 position. When an endstop is at the opposite side, it is a MAX. endstop. It is even written y-max. on it. -Olaf The green arrow represents x=0, y=0. y=0 is achieved byby JamesK - General
Re: 24V PSU for printer - 11 years ago
Quotedc42 Preferably, fit an over temperature cutout That's sound advice worth repeating. Unfortunately it's a lot easier to find thermal fuses with current ratings that would suit a mains powered heat bed than it is to find them for a large low voltage bed.by JamesK - Developers
Re: Video Update! Power Supply Issue? Motors only studder when Extruder and Heat bed are on - 11 years ago
QuoteXYZM Vref is from the adjustment pot, and black on ground.. Motor current rating is 1.5A Model: 42SHD0217-24B So don't exceed 0.75 V for X & Y, and probably less for E, depending on if you have the same or smaller motor there. I'd recommend setting 0.5V for X,Y & Z and seeing if that helps. That will give 1A output which the 8825s can handle without a heatsink, running about 35 deby JamesK - General
Re: Video Update! Power Supply Issue? Motors only studder when Extruder and Heat bed are on - 11 years ago
Where did you get those Vref numbers from? What current ratings are your motors? Current limit on polulu DRV8825 drivers is 2x the Vref, which would be very high with your settings, 3 to 4A. The drivers won't supply that and will shut down from thermal overload.by JamesK - General
Re: WD-11 vacuum tube base - 11 years ago
Don't the tubes get a bit on the hot side for fdm plastics? I seem to recall my tube bases are ceramic/porcelain. Ah - ignore me. These are tiny signal tubes with very low power heaters. I was thinking of power tubes for my audio amplifiers - a different sort of animal.by JamesK - Look what I made!
Re: Resolution along X and Y vs Z: are belts precise enough? - 11 years ago
Hi Olaf, What's the orange band around the middle of your pulleys?by JamesK - General
Re: Screw assortment - 11 years ago
Amazon.com have really increased their selection of small parts in the last couple of years. It can be a problem actually finding what you want though...by JamesK - Reprappers
Re: Where to get quality lm8uu linear bearings - 11 years ago
Has anyone tried the graphite lubed bronze bushings? (e.g. )by JamesK - Reprappers