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rob_colby
24-10-2010, 12:00 AM
Hey guys. I'm fairly new to all this, so forgive me if this may be a slightly stupid question, but......if i were to buy a plan for a cnc router, should i go for an MDF or aluminium construction?

Yes i will be trying to keep the cost down, but is MDF really a decent substitute?

Thanks,
Rob

Lee Roberts
24-10-2010, 12:14 PM
Hi Rob,

I built a Rockcliff Router (http://rockcliffcnc.com/Plans.aspx), the fixed gantry model using MDF. You Can view the build log by going here (http://www.mycncuk.com/forums/showthread.php/7-Rockcliff-Router-Build-MDF).

I need to finish updating my build log with the rest of the pics and so on, if you go with UN supported Linear Rail, please use anything 16mm in diameter or more. I used 12mm rail on my machine and the defection in rail that size was quite allot, I only had to breathe on the machine and the rails would bend.

An MDF machine dose have potential, below is some of the first cuts I did with mine:

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Next is my attempt at working with some Ali, apart from the obvious in the picture when the cutter got stuck it also spilt the Z Axis plate right down the middle. In the above pic I was “having a play” with the spindle speed to see what would work and what wouldn’t, when the cutter got stuck it had just gone into the next plunge, for a deeper cut and I had increased the spindle speed.

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Everything got jammed up as you can see in the pic and it more or less ripped the machine apart. With that I stripped the machine down and burnt all the wood :lol:.

Personally if you can afford to use Ali, then I would suggest you do. If my machine had of been made from ali maybe all I would have lost was the end mill (cutter), for me a £25 cutter lost is worth less than the time I spent making the MDF plates and building the machine by hand. There is obviously more variables I haven’t commented on but my point to you really is, if you can, build a better/stronger machine to start with.

If you want to get something up and running to learn more about how things work in reality, using a pen on the machine to draw some patterns, and do some work in wood, with the odd bit of dog tag engraving, then an MDF machine will do the job don’t get me wrong.

At the time of building my rockcliff I had never even Tapped a thread in ali let alone anything else, maybe it was over enthusiastic and ignorant of me to assume I would be able to build a machine from wood and small linear gear, then start turning out parts made of metal in the glorious fashion we see others doing, I don’t know...

Hopefully I haven’t “put you off” building your own machine, my current machine is a work in progress but this time I have used 20m thick Ali plates all over and used 80x80mm Ali profile for the bed/frame construction. Hopefully this will be a much better/stronger machine to start with, time will tell.

One of the things I think new comer's over look as well is one of the best resources this site has to offer (if other members don’t mind me saying so), that is that you can be in direct contact with other members who have machines up and running and with time spent. Most of these guys are willing to help each other in any way they can, so with that in mind and with limited self ability to work with metal, why not commission other members to make your parts for you, using their machines.

Granted not every member is going to be up for that and it’s probably the case that their machines are tied up doing current jobs rather than them not wanting to help you.

Don’t be afraid to ask people for help!

Time for some inspiring photos me thinks :smile:

Below are some parts for my new machine, I designed these and then got another member to make them for me, obviously things cost money but you can see it allows you to maximize your creative potential and build what you want rather than “what you can manage on your own”.

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A long message this time Rob, aimed at everyone starting out not just you. Hopefully I have pointed out some things that are over looked in the excitement of “building your own machine” but really should be thought about. I know, i've been there!

If you’ve got any more questions please feel free to ask.

Regards,
Lee

Lee Roberts
24-10-2010, 12:27 PM
And would you look at that, when i logged in today the first thing i got was a "New PM Waiting" message from the site. I always read my PM's last and go over the new posts/threads first, then reading my PM's just before i plan to "walk away from the computer".

So i'v got a message from AdCNC (http://www.mycncuk.com/forums/member.php/1050-AdCNC) and here is what it said:


Hi Lee, Just letting you know if you need anything machining out of alloy/wood/plastic or what not or anything i can fit on my machine i will be more than happy to do for your machine build.

Just let me know ;)

Regards

Ad

So there you go people, a cnc machine ready and waiting to work for you :).

Regards,
Lee

AdCNC
24-10-2010, 09:36 PM
LOL cheers lee ;-D ..... Roll up roll up!!