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Rostock, Kossel, Simpson, 3DR, and more. See: http://reprap.org/wiki/Category:Delta. Previously named "Delta Robots and Stewart Platform"
Re: Wider Y bed carriage on MendelMax 1.5+ - 11 years ago
The main source of Y error on all these designs is the stiffness of the frame. If you are going to improve things, that's where I'd focus.by uncle_bob - General Mendel Topics
Re: please help me diagnose this problem [ SOLVED ] - 11 years ago
You got your math backwards on the Vref setting. The driver *shares* current between the two channels. If it's set to one amp, it shares out 0.7 of that to each channel. A one amp Vref setting puts 0.7A on the motor winding. The first step should be to multiply your desired current by 1.43 ( that is 1/ 0.7). For a 0.5A motor that gets you about 0.71A. That's what you want to calculate the Vrefby uncle_bob - Reprappers
Re: Hot motors - 11 years ago
If we are going to reserect a zombie thread .... 0.4V on the normal stepper controllers is a bit high. Something down in the 0.3 to 0.35 volt range is more rational for thes motors. There's a lot of math behind that which I can go into if you need it. The Z motors are running fine at your setting. They are wired in paralell, so they each get 1/2 the current of the other motors. Here is a plan:by uncle_bob - Reprappers
Re: Heatbed driving me crazy, Silicon replacement? - 11 years ago
If you use a clamp on DC meter, be sure to zero it first. Often they are set up for some monster current (like 200A) and the zero can wander a couple of amps. ------------- If you have half the current, you have half the power. That's not a good thing. The current plus voltage measurement is pretty definitive. You can mess up measuring one ohm with normal gear, but current and voltage are notby uncle_bob - Reprappers
Re: RepRapPro + SainSmart RAMPS 1.4 + LCD - 11 years ago
The temperatures you print at are set in Slic3r (or your equivalent). The firmware settings are used for warmup. You can simply tell the printer to print (rather than warming it up) and it will use the Slic3r numbers. I suspect that the button on your control board is broken (bad switch / bent pin / broken pin / bad cable / bad connector). All the info (rotation and push) comes through the sameby uncle_bob - General Mendel Topics
Re: Anyone know how to upgrade to dual print head? - 11 years ago
The plywood carriage likely will need to be replaced with a printed part. You only have one hole in the plywood. A dual extruder is going to need two holes. You also will (probably) loose X travel distance when you do the conversion. Most installs seem to take out an inch or two. The alternative would be to rebuild more than just the carriage. Rebuilding the frame gets you into essentially a wholby uncle_bob - General Mendel Topics
Re: Heatbed driving me crazy, Silicon replacement? - 11 years ago
Rather than measuring resistance it's perfectly rational to measure current. If you *know* your power supply is putting out 12V, the current will tell you the resistance. Hook the bed directly to the power supply and see what it reads. If it's 1 ohm you get 12 amps if it's 1.2 ohms you get 10 amps. Once you know the bed is right, hook it to the Ramps. Leave the heater off and hook your amp meterby uncle_bob - Reprappers
Re: Thinking of buying a Prusa i3 - 11 years ago
I'm not sure it's needed, but I put a fan on my ramps board. There are a number of different mounts. I used a push on one. The mount was a quick print. The fan was $2. ----- Another thing you can do now is to head over and get some glass cut. If you are doing it in the US, the critical dimension is that the width needs to be just under 8".by uncle_bob - General Mendel Topics
Re: Extruding feedrate and slipping - 11 years ago
When I did my MakerFarm, I "improved" the fan mount. They mount it close to the hot end. I decided to space it a bit back to reduce the clutter. Things did not go well. Move it back to their location, everything worked like a charm. I'm not sure you need a duct, but you do need air it the right place. ------- I just moved my printer to it's brand new table and that reminded me on another pointby uncle_bob - General Mendel Topics
Re: MakerFarm Prusa i3 - 11 years ago
If you have to do tricks to get your bed to heat to 110 in less than 10 minutes, something is wrong. You should fix the problem rather than coming up with tricks. Either your power supply is in trouble, your bed is wrong, or there's a connection problem. If it's a power supply issue or a connection problem you could start a fire or melt your Ramps board. Neither one is a good thing to have happenby uncle_bob - General Mendel Topics
Re: Heatbed driving me crazy, Silicon replacement? - 11 years ago
If you are at 3 ohms, you don't have anything even close to the proper design on the board. I suspect that you have a plated board that got very poorly done. Unless it's a very unusual process, you are likely to have significant hot spots on that board.by uncle_bob - Reprappers
Re: Problem configuring my hotend thermistor - 11 years ago
The thermistor is a temperature to resistance device. The A/D converter on the Mega board is a voltage to digits device. The ramps board converts the resistance of the thermistor to a voltage by putting it in a simple bridge circuit. With no thermistor attached, the bridge will apply maximum voltage to the A/D converter. That would tell the Mega that the thermistor is very cold. A very cold theby uncle_bob - Reprappers
Re: Problem with the extruder not "rising" far enough, and a few other newbie questions - 11 years ago
This thread has been dead for months, I doubt anybody is still looking for a solution. You probably will get better traction with a new thread.by uncle_bob - Reprappers
Re: Extruding feedrate and slipping - 11 years ago
Where is your fan pointing? You may want to restrict the air to only the plastic part of the J-Head and keep it away from the metal part. What kind of heater do you have on the J-Head? They seem to come with resistors and with 40W heater cartridges. The heater cartirges seem to work a little better.by uncle_bob - General Mendel Topics
Re: Why are my Circles still ovals? Ive ruled out backlash. - 11 years ago
You can print a lower, but wider cube to do this sort of calibration. Printing a 5 or 10 mm tall cube goes a lot faster than one that's 20 or 30 mm tall.... One that is 50 x 50 or 100 x 100 helps take out the "rough edge" errors. It may also give you more confidance in your calipers.by uncle_bob - General Mendel Topics
Re: Marlin Setting for Heatbed - 24V - 11 years ago
A properly designed power supply should put out a constant voltage right up to it's maximum current point. That's true weather it's a switcher or an analog regulated supply. Check the wiring with a DVM and see where your voltage drops are. This is just DC electronics. There's no magic in it. If the supply is putting out 24 volts and there's 24 volts on the heater all the time, the results willby uncle_bob - General Mendel Topics
Re: Problem configuring my hotend thermistor - 11 years ago
If your thermistor reads 13.5 ohms at room temperature, either it's very much the wrong part or your wires are shorted. Try: 1) Measure a known good resistor with your ohm meter to check it. Best to try something in the 50K to 200K range. 2) If your wires are cable tied down, undo the cable ties. Remeasure the thermistor. 3) If it still reads low, pull it out of the hot end and check it. It mayby uncle_bob - Reprappers
Re: Jamming with brand new J Head!!! LOL - 11 years ago
I think you would do better starting a new thread rather than re-starting one that's months dead.by uncle_bob - Reprappers
Re: Heatbed driving me crazy, Silicon replacement? - 11 years ago
Twice the resistance would give you half the power. That would at least double the heat up times. If you go into the design specs on the heat beds, they are very clear. The board should be made with rolled copper (not plated / electroless copper). The board shoud come out at 1.0 to 1.2 ohm. The people who sell the 2 ohm boards are selling scrap / junk parts. They have half the coppeer on them tby uncle_bob - Reprappers
Re: Enclosure and extractor fan - 11 years ago
Computer fans have major issues with back pressure. Their air flow drops off quickly as you restrict things with a pipe or something similar. Blowers are designed differently and they handle the back pressure much better.by uncle_bob - Reprappers
Re: Thinking of buying a Prusa i3 - 11 years ago
Small high precision inside holes are a challenge. If you want to fit a part tight to a shaft, then drilling it out is indeed the best approach. If you have the Magma, forget about buying any PLA. The Magma is not very PLA compatible. You can buy a J-Head for PLA, but swapping them is a 15 minute process. One hint - just build it the way the instructions say. Wait to improve it until *after*by uncle_bob - General Mendel Topics
Re: MendelMax printing help (weird prints) - 11 years ago
Since noting has changed I'd check: 1) Cleaning the rods 2) Lubrication 3) Loose bolts 4) Y table hitting the under structure of the frame 5) Y end stop wire (or other wires) catching the table.by uncle_bob - General Mendel Topics
Re: Why are my Circles still ovals? Ive ruled out backlash. - 11 years ago
First - what happens when you print something square? The issue could easily be X / Y calibration values. If it's acceleration, printing slowly should eliminate the issue. That's pretty easy to do as a debug tool.by uncle_bob - General Mendel Topics
Re: Enclosure and extractor fan - 11 years ago
If you do decide to seal up the box, there are tapes made for that purpose. They are a bit ugly, but quite cheap. One of them is gray in color and was originally designed for duct work .....by uncle_bob - Reprappers
Re: Next printer suggestions - 11 years ago
You need a way to control the temperature of the chamber in addition to just having a big box. That's likely to mean insulation, a heater, and a control system. I'd suggest planning all that out before starting.by uncle_bob - Reprappers
Re: Hobbed bolt problems - 11 years ago
I'd bet that you don't have the bolts that tension your extruder tight enough. They need to be mighty tight on the extruders I've seen.by uncle_bob - Reprappers
Re: Problem configuring my hotend thermistor - 11 years ago
The thermistors used are rated both for a resistance at room temperature *and* for a specific curve of resistance versus temperature. In order to work with the tables in Marlin, you need the *exact* temperature curve in the table. There are *lots* of different curves for thermistors. You *could* write your own thermistor table from a full data sheet on your thermistor. It's easier to spend the $3by uncle_bob - Reprappers
Re: Heatbed driving me crazy, Silicon replacement? - 11 years ago
The fan on my hot end pretty much blows on the heated bed. The air runs into the back of the X carriage and then goes straight down. I have not seen any issue with getting mine to 110C in 7 minutes with a very conventional 12V supply. My heated bed measures right at 1 ohm (as it should). The bed sits maybe 5 mm above a piece of plywood which acts as a back side insulator. The glass on top is 2.5by uncle_bob - Reprappers
Re: Extruding feedrate and slipping - 11 years ago
Glad to hear that you are happily printing!!!by uncle_bob - General Mendel Topics
Re: Pronterface Marlin Extruder Feedrate Problems - 11 years ago
Sorry, but no I've never seen a Buda or a KVR. I'd *like* to see one of each of them, but there's only so much money I can sneak into the "money to buy toys" fund.by uncle_bob - General Mendel Topics