new guy
 

Hi all.
I am paul from sunny south africa this will be my first build on this type of make, i have tryde to build a cnc router before but not so good so i am giving it a second try. lets see how this is going to pan out.
i see there is a couple of guys from south africa on the forum i would like to know where you are from if you dont mind.

thanks.:)

Welcome Paul! :)

Welcome to the group!

Welcome aboard. Stick to the plans and you will have a great CNC machine when you finish.

Welkom, PM my dan gee ek jou my details ek is in JHB en so ook `n hele paar ander manne.

thank you all for welcoming me i truely hope that this one will be 100% when it is done

Miniature MechMate suddenly cutting - Johannesburg, S.Africa
 

Hi all
Ok this has taken me longer that I wanted but it is done. Now I am cutting,as you can see this is not a full size machine the cutting area is 600 x 1000.
So far I am happy with what I have done. And I think it looks good.
I just need to put the name on.
O before I forget where do I get a number.
Attachment 14063

Attachment 14064

Attachment 14062.

And here is the big one in the making.


Attachment 14065

Why are your main beams upside down? (and your table supports come to mention it)

Not sure what you mean. I have moved the table suport down so that I don't add weight to the side beams and preventing it from bowing the table. Or am I not thinking right.

The table supports must be connected to the side beams, or else you will get a lot of vibration in those beams.

You are thinking right, just paranoid. :)
Don't worry about the side beams bow... you can put a few tons on it & its won't budge...

Ok I hear what you are saying gerald. The other reson why I put it at the bottom is that I used a smaller beam not a 150mm. So that will give me the same Z clearance as a 150 beam. So if I run a short suport from the table suport to the bottom of the side beam then that will take care of the vibration( right?).
Thanks ken for your in put but you will understand now wwhy I say it wil bow as I am using a 100mm beam.

The worst bending of the side beams is horizontal, when the y-axis has to reverse direction rapidly. Try cutting some text (letters) and you will be amazed to see all the shaking (probably consider adding diagonal braces on the legs as well)

Ok will do thanks gerald. Who will give a number for my small machine.

Gerald I want to cut a product called( trespa) it is a resin board what will you sugest as cutting speed and feed and the bit to use if you can help. Thanks

Here is a better view of my mini mm Attachment 14068

Attachment 14067

Your main beams on the sides are upside down, the long edge (that the rail is supposed to be fixed to) is at the bottom and the shorter edge is at the top, the reason they are done like this is to maximise the length of beam under the rails, the way you have them is of no benefit so you could have just cut them straight...:confused:

:DOk that is what you mean. I cut them longer so that I can do it the other way around. It just looks better to me if it is this way round.:)
Thanks for your comments I am starting to understand why the mm is design the way it is. Talking about that who did design it?

In response to post #14, I think with some logos applied, it would certainly qualify for a #.
Enjoy using it.

Good will make a plan to get it on asap thanks.

Gerald designed the MM !

How about a close up of the Y car !

Paul，with such a short span, even 50mm C channel can take a few tons without problem...
Lately, I did a stress analysis on a pin supported 1200mm span 50x100x5mm Channel, I get 0.01mm deflection at the middle of the span with point load of 10kN.

Is the Y car in the top pictures a scaled down version?

Ken, my gut feel is that your beam calc is not correct. Maybe 10x greater deflection? (I havn't calculated these things for a long time)

I'm surprised too... but the point is we all over design excessively... even if I made mistake on 1 decimal point :) because we trusted our eye too much LOL!!!

The reason for my simulation was to convince a client/friend that there are no need to replace the 50x100mmx5mm thk sheet metal channel beam to a 6". BUT THAN AGAIN, for the sake of indulging his visual/psychological satisfaction, I went with 6"x2" since he is paying the extra :)

To respond to steve, yes it is scaled down it was not easy but I got it done. How ever I need to increas the motor mounting plate thikness to 3mm. And I think what you guys call the Y car I call the X car I made it out of one piece bend the sides and not welded.

This is a genuine Mini MM :)
Great job!

Just want to thank gerald for a great design proudly south african. I am also glad to see not all the great minds have left the country. This machine must be strongly premoted in sa so that the cnc world can be turnd on its head in this country every guy wants to get rich quick on cnc and over charge.

Thanks ken will see how it hold up will keep you guys posted.

Hi all.
Can any one help with this.
I have picked up a constant buzzing noise on one of my motors any idea as to what it can be? It is not very loud.
Thanks