T3P3 Kossel Mini Kit Release 2

Assembly Instructions

Chapter 15 - Electronics bracket,  USB/power plate and electronics cooling fan

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Think3DPrint3D Ltd


1501 Parts needed - Electronics bracket

Printed electronics bracket

M3 x 10 socket capscrews x 2

M3 flat washers x 2

1502 Fit Electronics bracket

Align 2 nuts in the bottom inside channel of the Y-Z side of the frame base with the holes in the electronics bracket.

Insert 2 M10 capscrews with washers , engage with nuts and partly tighten. Slide the plate to the left until it is about 1mm clear of the corner of the Z motor and tighten the capscrews.

1503 Parts needed - USB/power plate

Printed face-plate.

USB B female-male extension lead with 2 Pozi mounting setscrews.

12V power lead (socket pre-wired with fitted RAMPS power plug)

On-off switch

M3 x 8 socket capscrews x 4

1504 Fit USB/Power plate

The plate is fitted to the X-Z side of the frame base.

First fit the Molex 10-way power socket to the printed plate. The green RAMPS plug will not fit through the gap between the extrusions, so push the socket end of the power lead through the gap from behind.

Note: The plate has been printed with very little clearance to ensure that the panel-mount plug stays snapped into place once fitted.  It may require some force to push the plug fully in. If it won’t fit, carefully cut away a little plastic until it does.

Fit the on-off switch to the plate. It should also be a tight fit. Fit the bayonet connectors to the spade terminals on the switch. They are not polarised so can go either way. Production switch cables may vary in colour.

Fit the USB socket to the back of the plate using the Pozi capscrews supplied with it.

Locate the 4 nuts you inserted in the front channels of the extrusions during base assembly and align them approximately with the holes in the plate

Insert the 4 M3 x 8 capscrews in the corner holes. Align the capscrews with their nuts, screw in loosely, centre the plate on the X-Z side of the base and tighten up.


1505 Test Power supply

Put the printer power switch in the OFF position.

Connect the Dell DA2 power supply unit to a mains outlet socket with the power lead provided, but do not switch on yet. Plug the Molex-type 12V DC lead into the left-hand 8 ways of the 10-way socket you have just fitted to the printer.  (We had to use a 10-way socket because the Dell plug will not fit a standard 8-way one).

Leave the printer switch OFF and turn power ON at the mains. The LED on the PSU should glow amber or red

Turn the printer switch ON and the LED on the PSU should change to green.

Switch the printer power switch OFF, switch OFF and unplug the power lead at the mains outlet, disconnect the power supply from the printer and  set it aside for later.


1506 Electronics cooling fan

Parts needed

40mm cooling fan with Molex SL-type connector

M3x16 socket capscrews x 2

M3 washers x 2

12mm M3 Nylon M/F PCB standoffs (may be black or white)

A fan splitter cable is included to allow 2 fan feeds from the RAMPS, but is only needed during the wiring up stage.

Fan Installation

This is probably easiest done with the printer upside down, and all the pictures are taken with the printer oriented that way.

Locate the 2 nuts in the inside of the lower X-Y base extrusion (uppermost in the picture), and slide them towards the centre until they are about 35mm apart.


Screw the nylon standoffs into the nuts using your fingers. They will only go in part way before the male threaded end hits the bottom of the channel. Back them off slightly so the nuts can still slide in the channel.

Insert the M3x16 capscrews in the fan from the label side with the power lead exiting the fan next to the left-hand screw. Fit the flat washers to the screws on the other side of the fan, insert screws into threaded holes in standoffs and screw up finger-tight

Tighten the standoffs, but be careful not to overtighten as the nylon threads are easily stripped.

Finally tighten the socket capscrews so they hold the fan firmly on the standoffs. Once again, do not overtighten!

Now go on to the next Chapter.