Phebe on Velleman

[Diry Steve]

I seem to be getting varying temps without adjusting the temperature, not way way out of range, just inconsistent temps.

I am also only using about the lower 20 percent on the temperature adjustment range up to 120 degrees c.

Any suggestions? Would like broader range on the usable adjustment, and consistent temps.

Would like a range of 50 to 150 degrees C.

Thanks.

[Fiero2M6]

Check out the instruction sheet that came with the Velleman:
http://www.vellemanusa.com/downloads/0/ ... _mk138.pdf

Increase R7 to decrease the hysteresis.

The SeeMeCNC Electronics Manual reccomends replacing resistor R5 with 10K to 18K ohm for higher temperature control.

I don't have a HPB, but I think this will work.

[stienman]

Keep in mind that the temperature across the bed is uneven, depending on air currents in the environment, and how you have it mounted and insulated.

Always measure the temperature in the same spot, and make sure there aren't any fans or vents blowing air around the room.

I set my bed to 70C for ABS, and during the build the center of the plate and object go above 100C, while the edges (where my sensor is anyway) stay around 70-75C. As long as it's warm enough, a 10-20 degree temperature difference can still produce good prints, so while excellent temperature control is desired, it's not always necessary.