Excellent work @dcorb

(When I saw the first pictures I was concerned about a stiffness / rigidity issue with the X axis but I see from later pictures that you have changed that axis to fully supported rails - a much improved design ).

Tweakie.

 

I really like the bed. Are you going to have a spoil board on top of the Aluminum? I suspect you might need supports for the y axis linear rails too. Looking at your parts/price list, for the few dollars the x axis cost, it would be a shame to not support them too.

I wish we had your steel prices! I recently paid double what you did for a stick of 2x2.

Awesome build!

 

Ahhh, yes. The old friend of a friend's second cousin, twice removed works for a guy who knows another guy, who can get it from a sister trick. However you got it, it's a great find and where is McNeilus Steel????

 

I used to sell tools and equipment after I retired from the Army. And it seems I recall a company that makes Concrete trucks that's located there. I was there a couple times to help solve tooling issues. A nice small town.

 

"The first was a MDF design and the second was a Shapeoko. Did not really like either of those designs so I started my own."
Please tell the reasons you do not like your first and second design.

 

A part of that may be due to the poor performance we all have seen from mdf furniture and other applications where it failed. I think a lot of the poor feelings most have could be addressed by education into the various grades and types of MDF that are availible. Just as the term "Plywood" is used to generically refer to sheet wood layers that have been bonded together, but range from CDX plywood (3/4" 6 plys) which is used in rough carpentry to imported Baltic Birch plywood (3/4" 15+ layers) which is sought by homebuilt airplane builders.

I use Medex MDF as a base to form my pottery on. It is water resistant and does not swell like other grades of MDF will. MDF from a home center is typically the lowest quality product available to the store's buyers. There is one grade of mdf that is rated for use with exterior signs. I've gotten some pieces of it from a friend who's in the sign business. It's very tough and very stable, totally non reactive to water. I don't know what the binder is that's mixed with the paper byproducts, but it's almost like plastic - it will even take a edge like a knife. It won't last long but I was amazed at how sharp it could be shaped to.

Would I used this super MDF to build a CNC? I'll just say that I would not be afraid to. Would I build a "proof of concept" from regular plain MDF? Yes, but I'd not operate it like that any longer than I was forced too.

 

I'm just getting into the beginning stages of a cnc router what type of program are you using to run your stepper motors thank.

 

I use medite mdf here in uk as its id say at least a third more dense than its competition but even the moisture resistant sheets swell in high humidity. Awful stuff all of it.

An mdf router.. If your making a throw away single use machine then it might work for a day if your lucky.

Big problem with it is how much it expands as you cut it, say you drill a hole of 4mm. Which after you remove the drill measures 3.7mm so your m4 bolt doesn't fit because what you have is a 4mm hole with 0.3mm of swelled fluffy stuff in it. So you open the hole up to 4.3mm so the bolt fits only its now mated on this fluffy stuff that's hugely unstable. Add some vibration and now you have a wobbly bolt.

Mdf is only good for one thing imo, and that's sacrificial/spoil boards.

 

No video of it running. Wonder how often it requires a rebuild.

 

Yeah

Seems very slow for a large machine, I expect the due to its max cutting load.

But fair play it works, wonder how he got around the swelling issue.

 

Simple, he doesn't live in the UK....

 

Simple, he doesn't live in the UK....[/QUOTE]

You know that's likely it. Lol.

Leave an 18mm sheet in a garage or shed over winter here, guarantee its not 18mm come spring.

Just measured what was an 18mm sheet I've used as a desk top in my unit. 18.46mm bearing in mind this was new just 3 months ago. Had nothing spilt on it just the crappy climate.

 

Yeah, I hear ny get quite a big freeze. Is it true people get killed by falling icicles?

 

Sealing MDF with paint or sealer will allow it live in a humid climate.

 

I'm really hoping to see updates on this design. I'm really interested in building a cnc router based on this design. As much as I like the products that Openbuilds sells in the shop i'm afraid they are outside of my disability induced budget and this one looks like it might be more affordable for me.