Bunnygirl's : My CNC

[bunnygirl80]

Hi guys,

Welcome to our CNC build. Well, our CNC project will be a combined effort between Pete and I. It will truly test our patience and skills working together and I';m really not sure how long he can tolerate me bossing him around!  Pete (bless him) came home from work (really tired) and then popped over to B&Q to buy 2 x 12mm 606mm x 1200mm MDF sheets. Oh! Well! We';re off to a good start, he';s already listening!  ::)

The 600mm, 880mm rods and the 8mm threaded rods have arrived.

So, tomorrow evening, we';re starting with cutting the base. Will post pictures as we progress. Now where';s that cat';o';9 gone!

Stef

[bunnygirl80]

Wheyy! The build is under way. Last night we ( well Pete really, I don';t like taking credit for his work, i was only looking as he was sweating in his shorts ). The base and working area is now complete, although not assembled yet. The next stage is to assemble and then prepare the base ends for the rods and thread.

Chris I will need a word with you about the thread and how we will attach to the working area. Pete had some ideas, but I';ve stopped him and told him that this has to be replicated by other members. So, everything has to be obtainable!

So far we';ve used two 1200 x 603 sheets of MDF 12mm thick and some 2 inches x 4 inches studding for the base support. Both were purchased from B&Q.

Anyway, here are the photos so far...

[bunnygirl80]

The y axis is now complete. Here';s a demo video...

2013 09 07 cnc 1

[teslahed]

That looks very good. Do you have any close up shots of where the screw thread axle goes through the wood? I am interested to see how you';ve done that.

[bunnygirl80]

Hi Chris,

Pete here! At the moment it';s just a 8mm hole. I';ve filed the threaded rod down using the technique you explained from John with a file and a drill and the threaded rod is now down to 7mm. So we will need some 7mm bearings (not the linear type) to complete the final fit. I';ll have a look for these this evening and let you know.

Speak later mate, off for some home brew!

Pete

[teslahed]

No hurry Pete (and Stef). I look forward to seeing the results whenever - and hearing what you think of the homebrew.

www.rcbearings.co.uk is the website i have used in the past (and we were looking at in the pub). They have a very good range including those flanged bearings.

[bunnygirl80]

We';ve now purchased these Delrin anti backlash blocks to ensure smooth operation of the threaded rod.

http://www.ebay.co.uk/itm/160974239019?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

[philtrum]

they look like a good idea, as they also act as the bracket, nice find Stef/Pete

[teslahed]

I will get some of those as well. 3 pieces are enough i take it?

[guest325]

Best way I';ve found to paint mdf is to put a coat of diluted pva on before attempting to put any paint on it, especially the side edges - I often use a second coat. I then use an oil or solvent based undercoat/primer and finish with one or two top coats.

[mogwai101]

What will the plateform (CNC) allow you to do?
What programme will you use to drive the tools/platforme?

For the guides, did you not find that the filing process gives you an irregular rod (varying diam) that will give some loss of control?  Why not use a rod of the desired diam and put a thread on each end (to fix it) and a linear bearing on the slid to travel on the machined rod that will have much better tolerances than the filed job?

The video look good with the table moving very smoothly.  Look forward to seeing the x direction added.

[bunnygirl80]

I will get some of those as well. 3 pieces are enough i take it?

Hi Chris,

Yeah, 3 delrin blocks are enough, one for each axis.

Stef

[teslahed]

www.rcbearings.co.uk have lots of odd sizes including 7mm flanged bearings;

http://www.rcbearings.co.uk/index.php?route=product/product&filter_name=flanged+&page=2&product_id=622

I';m thinking the flanges might be useful for sinking them into wood end panels.

[teslahed]

Stef - can you remind me what size you';ve cut the A3 tray that slides backwards and forwards? Did you cut it 300x420 or slightly larger?

I am going to make a start on cutting my MDF later today.

[bunnygirl80]

Stef - can you remind me what size you';ve cut the A3 tray that slides backwards and forwards? Did you cut it 300x420 or slightly larger?

I am going to make a start on cutting my MDF later today.

Hi Chris,

Yes, it';s 420 x 300 exactly.

Stef

[bunnygirl80]

The delrin anti-backlash blocks have arrived and have now been fitted to the bed of the cnc (y axis). The next step now is to start work on the vertical x axis.