TechnoSyndicate

July 28, 2014

Qu-Bd or Quintessential Universal Building Devices official contact information:

Filed under: . — VIP @ 13:45

Corporate name of the business is Qu-Bd, inc.

David Mainard is the person to serve the lawsuit.

Corporate address is 8 Cape Cod Court Little Rock 72212

This data is accurate as of 07/28/2014

 

Here is the contact info:

David Mainard – President
davidm@qu-bd.com

Nathan Myers – Head of Design
(501)400-6333
nathanm@qu-bd.com

Chelsea Thompson
chelseat@qu-bd.com

Courtney Kinggard
courtneyk@qu-bd.com

 

 

January 7, 2014

Don’t buy QU-BD 3D printers.

Filed under: . — VIP @ 22:08

Here are good reasons not to buy QU-BD 3D printers.

I don’t think that this company will grow to the size where it will get a CNET review. Besides very bad customer service, there are hardware flaws that prevent this printer from printing to the specifications that are listed on company website.

The following subjects recur on the official forum as constructive criticism, but design of the printer remains unaltered so far.

Official specifications may be found here:

http://store.qu-bd.com/product.php?id_product=43

  1. Print table is not supported by lead screws where the center of gravity is – this is why it is always cocked since basalt is heavy. Geometric center and center of gravity aren’t the same thing in this case.
  2. Z limit switch design is very poor.
  3. Extruder starts skipping and printer stops printing several hours into a complicated print. No spring-loaded wheel to press the filament against rollers.
  4. Extruder wheels that move the filament get clogged very easily. Plastic fills teeth.
  5. Extruder has no hose or spring to guide the filament dead on the center.
  6. Poor wiring design – wires can wear from touching moving parts.
  7. Y axis cog belts ride on paired ball bearings with washers at their sides, as idler cogs. The washers are not spinning so they will wear cog belts.
  8. Fan in the extruder is attached with one bolt. Extruder pivots on one bolt that is screwed into a motor. Easy to strip threads this way…
  9. Basalt is thick and takes more than an hour to heat.
  10. Silicone on the bottom of the basalt will peel off sooner than the machine will wear out.
  11. Cog belts are glued to the parts they move. How am I supposed to replace them?
  12. No cog belt tensioners – one cog belt is sloppier than another. This causes Y axis to cock and results waves on the printed part’s faces. For reference: those waves are bigger than 0.1mm print layer. Printing gears and precision parts will be a problem.
  13. X cog belt is glued to the motor that is intended to pivot. (for safety, as I was explained.) So If extruder does get lifted, X axis shifts.
  14. Extruder has no cooling fan for the filament. Only to cool itself.
  15. Wires would not let anyone use cover plates to cover the sides of the printer where special indentations are milled for that and holes have tapped threads. This machining operation is useless.

Still want to buy it? They may take your money and ship the printer to you in several months. This is how this company operates.

Read the complaints on the official forum: http://www.fabric8r.com/forums/forumdisplay.php?3-Official-Manufacturer-Forums

You will find a lot of bizarre and strange complaints there. That involves shipping, customer service and faulty hardware.

In the past QU-BD would credit itself by delaying shipment of the merchandise beyond established shipping dates.

I had a very bad experience with this business. My printer is broken because silicone peeled off from the basalt base and the heater is broken. QU-BD refuses to refund the machine.

December 25, 2012

Распиновка выводов шагового двигателя, который используется на станке ЧПУ – конструкторе «Кулибин».

Filed under: General technical reference — VIP @ 23:59

На некоторых моторах чёрные провода заменены на синие.

December 23, 2012

Would this mechanism work or not?

Filed under: To blow your mind — VIP @ 06:13

Sometimes there is a situation when a theoretical mechanism cannot be proven to be able to work unless it is built out of rigid and durable materials.

Here is a mechanism that I invented, although I am not sure if I am the first person to think about this design:

A planetary gear set that can allow the center to be moved against the outer ring. This device can also function as an adjustable variable displacement pump.

However I am not sure if the planet gear pairs can really tilt, causing the distance from the sun gear to the ring gear to change.

Theoretically that distance can change as much as a planet gear diameter minus the teeth height if this mechanism would not mechanically interfere and would be able to function at all.

It may be that the inner and the outer gear in a pair (or a greater number) of planet gears will have to be different diameters to compensate for a different gear tooth number of the ring and the sun. This will ensure that they twist against the sun and the ring, giving the sun two degrees of freedom.

If it is mathematically impossible to make a one-step gear set to accommodate for that difference, than a multi-step gear reduction may be utilized.

This mechanism would be too expensive to be built anyways so it will probably remain as a thought experiment.

What can be changed to make it work:

  • Different diameters of the planet gear pairs. (Green)
  • Different number of planet gear groups. (Green)
  • Different arrangement of planet gear linkages. (Brown, Beige)
  • Different planet gear configurations. (Green)
  • Different number of planet gears in each group. (Green)
  • Different diameters of individual planet gears in a group to compensate for different gear ratio between the sun and the ring.(Green)

 

Mechanism

Variable displacement pump

 

Idea and article by Vladimir Tolskiy

Common 3.5mm 1/8 inch audio jacks and their pinouts:

Filed under: General technical reference — VIP @ 05:49

Generic 3.5mm jack stereo connector, common mono headset connector, Nokia stereo headset connector, Apple stereo headset connector.

December 7, 2012

Hobby Computer Numerical Control Milling Machine – control module and important aspect of mechanism design

Filed under: To blow your mind — VIP @ 07:42

Main board:

This is the board that I used to control my machine after I failed to come up with a budget solution to control my machine with a USB signal. I bought it off Ebay, from some undefined Chinese supplier.

An image of my masterpiece. All control module parts are screwed to the main plywood frame while plastic beads were used to raise the boards above the plywood surface. Few components are bolted.

Limit switches are connected to the board

Main interface board: Left connector is to control the mill motor, or in my case a relay that powers the mill motor. Right connector is for the limit switch inputs and other programmable inputs into the board that are sent to the computer through LPT port.
Stepper motor connector for each of three axes.

This connector is for the stepper motor outputs.

Right to left A-, A+, B-, B+. If you reverse the connections, the stepper motor will run in the opposite direction. This can be adjusted in the software.

Various motor regimes.

Switches to change different operation regimes of the stepper motors.
Connectors on the control module

Left to right: AC power connector that is commonly found in computers, ‘my’ DB-25 connector that connects to the electrical components of the CNC mill, a connector that is used for a wired remote control to move the machine components manually, the LPT port that is used to interface the computer.
Control board.

Seen from left to right: software emergency stop button that sends a signal to the computer via LPT port, PWM mill speed control knob that is pressed on the shaft of a variable resistor,

AC power switch for the whole board.

Additional relay to control the mill motor

Relay that toggles that opens and closes the circuit of the DC motor that drives the spindle.
PWM smooth speed adjustment for the mill motor

A smooth PWM DC current control module that is used to change the mill rotation speed. Three wires that are seen on the left lead to the variable resistor that is mounted on the control board.
Power supplies

Two power supplies for outdoor lighting systems: Left power supply outputs 12VDC for the control board, the stepper motors and the warning light, the right power supply outputs 24VDC for the spindle motor.
Power supply breakout

This is how the terminals of the power supply look like.

The ground symbol marks the AC ground, not the DC 0V rail.

Power supply rating

One of the power supplies outputs 24V, 6.5A and another power supply outputs 12V, 13A.
Limit switches

This is how my typical limit switch looks like on the CNC mill. For economic reasons and for the reasons of convenience I used switches that are normally open. Appropriate software adjustments had to be made.
Limit switch override

This is the switch that is Normally Closed. All limit switches in the CNC machine are Normally Open. If I manage to get my machine to move onto a limit switch and cause it to stay closed, causing the software to shut the machine controls off, I can hold this switch and disable the limit switches temporarily to let me move the machine ‘off’ the limit switch so it will open, in order for the proper function of the machine.
DB-25 connector

To quickly connect my CNC mill to the control board, I used the DB-25 LPT connector. I had used it only as a connector so never plug computer equipment into the male or female connector that is used to carry power for the machine operation. This connector is rated for 2A of current for each pin.
Plastic bead standoffs

My traditional way of connecting parallel planes when I build my prototypes. I use a machine screw with standard beads that can be found in craft stores as spacers.
Stepper motor, helical coupling, lead screw

Right to left: stepper motor, helical coupling and a lead screw. The lead screw thread is M6, I believe. Shaft diameter of the motor was 5mm.
Mill motor

Mill motor with a bit chuck and a clamp that holds it against the CNC mill frame.
Mill motor with a coiled power cable

Another view of the mill motor.
Limit switch above the mill motor.

Lead screw and lead nut

This is how the lead nut is attached to the frame components in and relationship to the lead screw.

Notice the white fluoroplast inserts between the moving parts, which are pressed in place by the set screws.

December 5, 2012

Please Donate

Filed under: ., To blow your mind — VIP @ 05:08

I am trying to undertake a rather complicated project in my home environment.

The goal is to use the single wire electricity as a continuous source of DC power.

This project calls for expensive parts that I cannot afford on my own.

Thank you.

December 3, 2012

Another possible application for the ‘single wire’ electricity – Scanning Electronic Microscopes and Scanning Tunneling Microscopes

Filed under: To blow your mind — VIP @ 02:40

I thought of quite another way to implicate this interesting phenomenon of single wire electricity after having a conversation with my friend, who is currently a physics student. This is probably not an application, but more of a suggestion for a field of research.

Scanning Electron Microscopes or Scanning Tunneling Microscopes may indeed be improved by using a variable frequency high voltage pulse in addition to the conventional cathode ray. This may allow scientists to not just view the sample but try to influence it and observe the electrodynamic interactions within the sample. A electronic nano-component may be examined in terms of how it reacts to the inflow and outflow of electrons.

This technology may be very beneficial to the development of the solar panels of the future.

If Single Wire Electricity is going to be used with microscopes, it has to be properly compensated for in the output signal that the device will produce.

Currently I conducted an experiment that allowed me to derive a mathematical formula that may be useful for dealing with the single-wire electricity.

I have no facilities available to me to research the possibility of using single wire electricity for SEM and STM applications. I am a hobbyist, after all.

Vladimir Tolskiy

November 12, 2012

High Voltage exploration – Going back to the roots

Filed under: To blow your mind — VIP @ 05:02

At this point I am not sure what determines the rate at which the capacitor charges. I suspect that diodes may leak in reverse and cause energy to be lost. So I decided to go back to the roots and make a circuit that consists of many diodes that are connected in series and see if this circuit could power a load directly, without a capacitor or with enough current to keep the capacitor charged.

I can only judge by the time it takes to charge a capacitor so the light will blink when I close the switch.

I was very surprised to find that the circuit performs about as well as a circuit with only two diodes in the Avramenko Fork.

I also recently realized that I drew the Avramenko Fork diodes backwards in relationship to the rest of the circuit in my previous post!!! I will correct that soon. Thanks.

Powering a low voltage DC load from a single-pole High Voltage power supply

Filed under: To blow your mind — VIP @ 01:33

Warning! High Voltage experiments possess a potential danger of electrocution and fire. Please be cautious when performing those experiments. Children should be supervised by an adult when experimenting with high voltage. High voltage can cause undesired electromagnetic interference. This interference can cause pacemakers and other medical devices to malfunction.

As a conclusion to the line of experiments single line power transition I want to showcase a device that caused a small electric DC motor to rotate by utilizing energy that was obtained through a single power line. The Avramenko Fork cannot generate enough power to run the motor constantly from the supply that I have.

Therefore I employed a crowbar circuit it that discharges a electrolytic capacitor and powers the motor only when the voltage in an electrolytic capacitor is above 5V. The motor runs for about five seconds and then the circuit recharges for about a minute; than the same thing happens again.

Some very nice people helped me design a thyristor crowbar circuit that would discharge a capacitor through a motor when enough voltage had accumulated in a capacitor. So the overall circuit looks like this:

  1. D2 is some Zener Diode that I happened to have that is rated to discharge at 5.1V.
  2. D1 is a NTE5455 Thyristor
  3. D3 and D4 are simple ‘1n something’ radio-frequency rectifier diodes. No high voltage diodes are required because this circuit opens at voltage that is higher than 5.1 volts.
  4. R1 is 100 Ohms
  5. R2 is 100 Kilo ohms
  6. R3 (The Load) is a 9VDC electric motor that was used to move the drawer of a CD-ROM.
  7. C1 is probably 100pf, but the circuit works well without it.
  8. C2 is a Rubycon 6.3 Volt 5600 Micro Farad Electrolytic capacitor.

    The frequency of this circuit switching a motor load on depends on C2, but there is no linear relationship between capacitance and the time it takes to charge.

    I think that some other qualities, such as internal leakage and lead resistance may contribute to that.

  9. I also connected another diode across the load since it is an inductive load and can produce voltage spikes of its own. I had used the same diode as in D3 and D4 for that purpose. (Not on the circuit diagram.) Make sure that you connect the diode so it does not conduct when the load is energized.

At this point the circuit is probably not safe for powering loads that have ICs in them since high voltage is pulsing throughout the DC circuit and can probably destroy fine electronic components. The motor can shock you if you touch it.

I hypothesized that introducing Q-loops into the circuit can prevent this voltage from conducting through a circuit and making it safer to use.

Q-loops may need to be placed before or after the electrolytic capacitor. I will need to measure the frequency of the high voltage power supply to choose the right values for the induction and capacitance in the Q-loops.

This is how the hypothetic circuit may look like.

The Avramenko Fork

This picture shows the way I had placed diodes in my circuit, but I may be wrong.

Electrolytic capacitors seem to leak and prevent high voltage from building up inside them, even the voltage they are rated for. I would try to build a circuit that involves high capacitance ceramic capacitors in the future and see how they perform.

I had connected the circuit with a motor to the single-pole power supply through a ceramic capacitor within the single wire ‘circuit’ and noticed that it happens to pulse the motor about as often as when the circuit was connected to a single pole supply with a solid wire.

Vladimir Tolskiy.

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