Gus's TLAR Laser build 0.6x0.9m (24" x 35")

[Ischcuch]

I have to start with a big THANK YOU to all the participants on buildlog.net! Your ingenuity, enthusiasm and willingness to share have motivated me to give it a go myself. I will share my experience (albeit slow) alike!

Short Intro:
First and foremost: My lovely wife and best friend Julie allowed me the time and the opportunity to take over the dining room for this folley
I noticed the TLAR acronym in another thread, loved it, and added it to the subject!
I love wood! (and statistics)
hoarder of bits and pieces.
South African thriving in the UK
Metric, but can convert..
limited understanding of ohms law

It took some time (lurking around..) to commit to a build log so I will back-track a little.

1303 - Bitten and interested!

130406 I have some reclaimed 45x45mm and bigger extrusions available. I purchased an all material Bosch blade to cut them.

[Ischcuch]

I Have moved into the dining room.

The frame is now complete and a bit larger than it looked on the drawing

The pre cut Makerslide (2 x 0.7m and 1 x 1m), V wheels and bearings have arrived from Makerslide Europe. I am pondering how to mount it to the 45x45 supports on the side of the frame.
Option A: Double sided tape
Option B: Drill through and use T nut
Option C: A+B
Any ideas welcome...

I have set up a cheap test board to learn the controls and drive the axis while i save for a DSP.

[TLHarrell]

Wow. That's a huge disparity between the two extrusions. I'm all for mechanical fastening being the better of the two choices. I would consider option 3: drill through the Makerslide, the side facing the 45x45 will be to clear the screw threads to attach into a T-nut in the 45x45. The outer side of the the Makerslide, drill to clear the head of the screw. So the screw will go inside the Makerslide and contact only the back face. I'd try it on a piece of scrap and see whether it deforms the Makerslide or not. You might need to use some sort of spacers in order to apply enough torque to the fasteners.

[Ischcuch]

Thanks TLHarrell,

Mechanical fixing seems to be the right way to go. I don't have any spare Makerslide to test with so I am looking around for a spacer to solve the problem....

Progress in the mean time:

130524
Gantry has been built and X axis cable chain added. I used IGUS samples that I obtained at a wood show in Germany (http://www.ligna.de). The 28mm wide chain was too heavy and did not move smoothly. I will use narrower 16mm chain and see how it works.

[Ischcuch]

130529
Ali brackets and Pem nuts were not suited to my manufacturing capability so here goes an acrylic fabricated alternative.

Parts for the assy from left to right:
3mm clear acrylic base plate
M6 square nut
5mm black acrylic centre plate
3mm clear acrylic cover plate
3M double sided self adhesive tape

Apply 3M self adhesive tape 9629PC and trim edges and holes

Stick parts together

Mounted plate! A bit rough around the edges but we will see if it works.

[bdring]

I like the captive nut method. The clear on black looks cool. You probably could substitute acrylic adhesive instead of the double sided tape.

[Ischcuch]

Good idea Bart,

I could not compress all the air out of the bond and it was left with a fuzzy look. I will try the adhesive to see if it will result in a clear bond

[cerocca]

Hi there Ischcuch,

nice to see your build log, also because I'm planning to build a machine pretty similar (at least in the dimensions) to yours

Because of this similiarity, can I ask you 2 questions?

1) which motors are you planning to use? NEMA17 or bigger?
2) is it possible to mount in your build a 60W laser, or the structure is still too small?

thanks since now, bye

C

[Ischcuch]

Hi Cerocca,

Thank you

I have Nema 17 stepper motors that I plan to drive with a tb6560 board to get it running. I will see if it works...

My frame is 1.6m wide on the outside and have 1.4m space available for the tube with 100mm clearance on the HV end.

I plan to buy a 40w tube to start with but will be able to fit a 60w tube from cncoltech as well. Here is a link to a 120w tube from Reci laser that is 1.4m long.

http://www.aliexpress.com/item/10000-ho ... 07717.html

I hope this helps. Happy building!

[Ischcuch]

Mechanical motion is nearly done!

I spaced the makerslide centrally on the 45x45 extrusion, sanded the contact faces, super glued it and connected it tightly with 3 x M4 cap screws on each rail.

When adding the Y Axis idlers i found out that I fixed the one Y axis makerslide upside down (with the groove to the top). It took some determination to break the superglue bond! I think the superglue and M4 combination will hold. The proof will be in the pudding!

Frame and gantry assembly:

Laser car detail (I added a bush on the right hand side as well so I can use another switch for X+ limit.

Gantry motor end detail with X+ limit switch

Electrical work is next.

I have a TB6560 3 axis board and a Siemens Logo 24o PLC. I will try to get the axis moving before committing to buy a laser tube and power supply.

My plan is as follows:

Mach 3 and TB6560 to drive:
- X and Y motion
- Z to fire laser through spindle relay (info gained from buildlog and cnczone). 130713 Edit: Laser fired directly through Mach 3 using an un assigned pin on TB6560 board.
- 4th axis connection to jog Z (focal distance) by an up/down button switch (not sure how yet).
- X home and X+ limit
- Y home and Y+ limit
- E stop
- Cover interlock

PLC to drive:
- programmable run-on function for extraction, cooling and air assist.
- timer for laser power supply being energised.
- timer for laser tube being energised.
- cooling monitor and alarm
- connection to e stop and cover interlock (not sure how to link this into the TB6560 yet) 130713 Edit - Solution: Double pole e stop pole 1 for TB6560 and pole 2 for PLC

I'm sure the next post will be a question....