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(SOLVED) 3d printer extruder not extruding enough?

Dear: LMR

Hello guys just to let you know I have been running into an extruding problem. It is definetly not a clogged nozzle or extruder because I have more than checked for both. You see the 3d printer is not extruding enough. I have to put force on the filament down the extruder to get filament moving.

The possible problems are numerous. You should know that I bought a new hotend for my 3d printer. The 3d printer hotend ran into a problem and the resistor came loose. That probably would be a fire hazard if I didn't buy a new hotend.

Raspberry PI robot book?

Hey folks! Just signed up about 20 minutes ago. Former Factory Mainenance Mechanic here, so I have a pretty decent knowledge of automation. My question is, is any of it useful for this hobby?

I just got a book called Make a Raspberry Pi-Controlled Robot by Wolfram Donat, and I am wanting to build something similar, but a lot more robust. Basically more like a robot mule. Something that can tote some pretty heavy payloads with a long working time. I have some ideas about that, but I will go into them later. Anyway, I just wanted to say Hi more than anything. Have a good day!

Why not make a Big Trak type robot?

It occurred to me, I haven't seen anyone make a Big Trak clone lately.  For those who don't know, Big Trak was a Milton Bradley's toy in 1979-80 that was recently brought back.  It was a truck that could be programmed to Move Forward a certain number of "units" (about 13 inches), Stop and Wait a certain number of seconds, Turn left or right a certain number of degrees (but, you had to test it on each type of flooring), Fire a laser gun, dump out stuff in a trailer, etc.

Books about starting an RC toy company?

Hi All,

I'm looking to find information/books on how a person would go about starting an independent RC toy company.

Speed controller

Hi all,

I'm curious as to what you guys are using for speed control. I've had a dig around the site and I'm not really finding the answer I'm looking for.

What I'd really like to know is, are rc car speed controllers suitable? I've been looking at them on eBay and they appear to offer high amperages, forward and reverse and relatively cheap prices.

Do these things work OK, with Arduino?

Are there better alternatives?

Does someone know of a post that will give me some insight?



Are TechShops any good, or is there a better national chain


I will be moving into a motor home eventually. I can't afford to fit an entire shop into one for many reasons. One being that most shop equipment is noisy and most rvers are retired and like their quiet.

So I'm thinking of a national chain of maker shops. TechShops seem to be good and have a decent range. I can have a 3d printer and some simple hand tools, and I should be able to build robotos without much problems. I should even be able to afford a Titan in the future, though getting it in and out of a motor home might be the bigger problem. :)

Any thoughts?

Use of the Website

Sorry but these stupid questions are not actually about robots as such. They are actually about how to use the LMR website. I couldn't find anywhere else on the site to raise these questions so my apologies if I'm doing something wrong. I have searched the site, found a few dusty corners I'd never noticed before, a few faqs and guides but still haven't found the answers I'm looking for.

Most Price Efficient Actuators for larger hexapod

I'm wanting to create a hexapod based robot out of PVC, maybe about 3 foot tall.
I'm not wanting to make it have to carry anything heavier than let's say 20lbs.

I'm still learning about some hardware in the actuators department, and know a lot of science, but not a lot of physics formulas. I'm considering trying to control each leg's from raise up to move forward by a solenoid, but need to know if I want to use a bi-directional solenoit, stepper motor, or something else to have the legs move forward and back when raised.

Question regarding Spider robot controller/Arduino Mega (1280)

Question regarding Spider robot controller/Arduino Mega (1280)

After some search I found the pin layout of the Spider controller:

One question:
Is it correct that the inner female pin is ground,
next inner male pin is GND
and outmost male pin is 5V?

All according to

USB ASP programmer not working with Arduino Micro

Hello everybody!

I'm currently working on a project using an Arduino Micro. Unfortunately, due to a soldering mishap, the micro USB port is not usable. Now, I'm trying to program the Arduino with its ICSP header using a USB ASP programmer. Whenever I try programming the Micro, I get this error message.

Let's Make Robots - Contact Us

You can now contact Let's Make Robots via our Support Center

Select the "Let's Make Robots" department from the drop down list.

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Issues with LMR saving progress

Is anyone else having issues with the LMR site now allowing to save progress? i tried clearing browser cache and even using a different browser to no avail

Aduino Uno with more beef

I have been quite frustrated using generic Arduino Uno boards with peripherals such as digital compass, IMU, and nrf24L01 radios. The problem usually manifests itself as not enough usable I/O pins, not enough power or ground pins, wrong sex on headers, an most importantly,insufficient 3.3V power. I have boards from Dagu & RFRobot that satisfy most of these issues but I need the Uno pin format to cleanly interface with the Dagu Scamper ComMotion shield.

Solution. Design my own board.

IR Tank Battle Bots

I want to make 2 robots out of Lego with tank treads and a turret that will shoot an "Ion Cannon" at the other bot. When hit, the bot will rock its wheels, make a sound and a point given to the victor. I want these to battle in an arena of fish tank gravel, and the turrets only will have left-right degrees of freedom in a maximum of a 180 degree spread (powered by a servo)

RobotShop Acquires LetsMakeRobots.com

RobotShop, the leading source for robots and robot parts on the web already hosts one of the largest communities of robot and drone enthusiasts. In 2010, in order to better serve their community by providing free information and articles accessible to all, RobotShop acquired GoRobotics.net, one of the most popular and oldest blogs on robots.

RF Link query

I have been designing a RC remote control for my plane/tricopter. I have documented the project at LMR 


Well,I have run into a problem. The NRF24L01+PA+LNA modules with SMA antenna I have been using so far has only been proved to give reliable connections upto 250m approx, but I want to make solid connections upto 600m atleast. Thus the NRF modules can't be used. I have some options here,either I will buy a radio from a online store, or I will plug in some RF link in my module. 

4 Axis Robotic Arm

     I am a beginner in robotics and currently I am trying to build a 4 axis robotic arm with rotating base and I need Kinematics Equations for this project . Can anyone help me with this. 

2D model of my robotic arm is attached

running 6S battery at 2S, then switching to 6S via radio control?

Hi All,

I want to test out a brushless RC system within 2S safe parameters, and then go into the danger 6S zone for a few seconds, then go back to 2S.  I will of course be using ESCs and motors that can handle the momentary 6S burst.

My question is, via radio control, how would I be able to switch the RC robot from 2S, to 6S, then back to 2S?  I have a cheap surface RC gun style 3 channel transmitter and receiver.

The 3rd channel looks like a good candidate for on/off switching, but i'm not sure how to do the 2S/6S switching.

Raspberry pi 2 + T'Rex controller -> battery

hi, I need to know, how to supply raspberry pi 2 and T'Rex controller together. I have this battery (http://emotors.cz/pohonne/11445-giant-power-nimh-1600mah-72v-10-20c-.html) - 5000 mAh, 7.2 V, 10-20C.

I dont know how big voltage can I connect to raspberry. If I can connect in series or paralel rasp with T'Rex to battery or I need new battery for rasp.

PS. - if you have some good article about connecting raspberry pi 2 to T'Rex (arduino) through I2C, send me that please :)

thanks :)