Ladies and Gentlemen we have steel! Melbourne,Australia
 

Hi everybody.

After much lurking and reading I have finally decided to take the plunge and build my own MechMate.

I have been enamored by cnc and the capability it presents to the perpetual tinkerer for many years. Consequently, I have spent many hours over the last couple of years reading everything I could find on the web.

I actually came across the MM site early on in my research but was frightened off by all the metal and the $$. I needed a cheaper option and so I focused on mdf based machines. Wood is cheaper and less scary :)

Late last year I took the plunge and built my first mdf cnc machine. A relatively small machine with a cutting area of ~700x700mm. For a hand made machine that uses skate bearings, althread drive screws and generally cheap bits and pieces it works surprisingly well.

However it does have problems.
- It's slow. I can only run it at max ~500-600 mm/min (not inches/min) before it starts to lose steps.
- Although impressively rigid it still has some flex at the router bit.
- It has backlash problems which are mainly evident when trying to drill small holes.
- At 700x700mm it is way too small (for my ego) :p

This was a fantastic experience but I did it without any direct support and made many mistakes. Still I learned a LOT.

One of the most important lessons I learned was that the most expensive part of the machine is not the structure, but the electronics and the linear drive system. Unfortunately any decent set of motors, bearings and rails required to run the larger machine I want are going to cost money. The saving is not going to be made by using MDF! In fact the few dollars saved here will only compromise rigidity, which defeats the purpose of spending money on the rest of the bits.

Initially I spent a few weeks trying to design my own steel machine. I quickly realised how much work that is and any mistakes here were going to be expensive and (with the weight of steel) possibly dangerous.

So here I am about 2 years later back at the MM site. This solution looks very reasonable now that I have spent (wasted?) countless hours and money doing it the hard way. Though I have no regrets because of what was learned, it's time to stop mucking around with toys and build a REAL machine.

I hope you will all be patient with me as I pick your brains on the various issues that are bound to arise.

I have been watching some of the local builds with particular interest as I am currently trying get my list of materials together and source them. I hope some of the Melbourne guys will be able to help me with some good local sources when I get to ordering local materials.

I promise I will read first before asking for hand outs.:)

As a final note I just want to thank everybody in advance (especially Gerald) for this fantastic resource. I look forward to my own serial number soon (what are we up to now?)

There ... it's done... I've introduced myself publicly ..... now I'm committed :)

Nick
Welcome to the pool. Come on in...the water is fine!

We're gentle - really.

Ask questions when your stumped, ask questions if your not....

Good luck,
Sean

Thanks Sean
Excited to be on board.

That's inviting trouble you realise. To paraphrase the great Bart Simpson..."What I don't know could fill a warehouse"

You may have to quit your day job ;)

Nick

Hi Nick,
Nice to see another build in Melbourne. Now we are 3. Plus 2 in Geelong. We can start investigating "bulk" orders for a few things (I have my electronics and steel, but am still shopping for racks, pinions, springs, Z-plate and a couple of the custom parts).

Contact Rick Nixon about the laser cut parts (he had extra sets cut when he built his machine) and to see his well built and functioning machine.

I paid around $1200 for steel from Moorabbin Steel for steel for an "overbuilt" 1200x2800 table with 350Z option (the BIG 300x95 beams were a bit more $ than the smaller ones) and this was a pretty good price when I compared a few quotes. More importantly the steel arrived and it was cut right and looks straight.

I've been shopping for 2 months now and it ain't over yet. Luckily I have full support from the minister for finances!
Good luck
Red

Welcome Nick! :)

Welcome Nick !!

Sing out if you have any questions mate!! good luck with the build.

Cheers
Tony.

Welcome to the club Nick! You won't regret it, the MM is a wonderful machine.

Looking at your past experience, the MM build would be relatively easy for you, and you have some people over there to go to...

good luck with the build, keep us posted!

Thanks guys. With such a great reception, I might just have to stick around :)

I have to say that, looking through the various threads here I am gobsmacked at the high quality of your builds. I clearly have a lot of learning to do when it comes to working with steel. Hope I can achieve similar results with your guidance.

My background is in software development. I have always been confident with wood as we did woodwork in secondary school, but steel is a whole other science.

A couple of years ago I took a weekend course in welding (stick). This gave me the confidence to consider steel for future projects.

Soon after that I bought a small (cheap) arc welder (see here). Figured I would only ever do small square tube stuff.

The question I have is will this be big enough to handle all the welding I need to do for some of the monster steel in this project. If not I may have to get a 15Amp power point and a bigger welder (more $$:()

I noticed Tony had to call in the big guns for some of his welding. Yikes!

Good idea Red. You are way ahead of me with your build but let me know if you are going to order something.

BTW I noticed you live very close to me. I am in Bentleigh. This could serve us both well.

Thanks...will do

I have dealt with Moorabbin Steel the couple of times I bought any. I am glad you recommend them as I have been very happy with their service (and patience!)

I also use Cost Less Nuts and Bolts (in Moorabbin) for any fixings. Also very helpful and well priced.

I too have dealt with Moorabbin steel on other projects, and have been very happy with their service and quality of work. I too live in Melbourne and will be looking at taking the leap into building a mechmate (or very similar) so if your looking into bulk ordering parts/components and saving on shipping, let me know.

PM sent to Tarlo

Structural gurus wanted
 

Update.

I have finally decided that the right size table to build is a 1220x2440. That took a lot of measuring and remeasuring of garage space (and a subsequent clean out ;))

After a bit (meaning a LOT) more reading I have come up with a design that allows me to better utilise the space under the table for storing long materials and sheets. This is a hybrid of a few ideas I have seen on the forum.

I was hoping that the structural engineers amongst you might cast an eye over it an let me know if this is likely to stand up to normal MM abuse. I am about to order steel and would hate to get it wrong at this early stage.

Some explanantions (all in millimeters):

1. Main x beams (dark blue) are 200x75 channel
2. Legs (red) are 75x75x3 box
3. Leg supports (green) are 50x50x3 box
4. Table surface supports (yellowish) are 75x40 channel
6. The two blue supports at the far end are for an indexer (some day)
7. I have added two little legs (green) to the bottom frame to provide additional support (ie prevent bowing) under the weight of sheet stock. This helps keep the sheet stock flat. Do I need these?
8. All legs will have leveling feet
9. Though I haven't drawn them, I intend to add wheels like Tony's here. This may mean I bring the bottom frame down further to avoid having to use extension rods like he did.
10. All welded

My main concern is that I have deviated from the original brace design and was wondering if I am significantly weakening the structure in some way.

Thanks in advance for any help :)

I think you would want those braces to come right down into the corner and then extend at a true 45 Deg for the best result.

Thanks Heath

I agree that the longer bracing is better...BUT...what I am hoping to achieve is a good middle ground solution that allows for more wide sheet storage (upwards as well as across) and general access under the table without sacrificing table stability.

Scot mentioned here that he has no stability issues with his table and he uses no bracing. So I figured if I use "some" bracing I could get the best of both worlds.

He does use thicker steel though. Maybe if I go 4mm instead?

Build it like you need it and if you have an issue - adjust accordingly. You should be fine

Nick,

I reckon your bracing will be just fine. I would imagine you would be sliding your boards under the table from the end, so you could extend the side braces to the lower rail and leave the others as shown.
I also think that the 50 x 50 x 3 would be more than enough to take the weight of the boards placed into the table without the smaller legs under.

Cheers
Tony.

Thanks guys,

That gives me a lot more confidence to go ahead.

Tony, you make a good point about the longer side braces so I will do that. As for the smaller legs, more than happy to get rid of those. They're just ugly ;)

Will order steel today!

Ladies and Gentlemen, we have steel!
 

I have been accumulating materials ...

Just received my shipment of steel today. I know this stuff is heavy but those x beams are killers!
I'm going to have to find me some pipe-bending gorillas to lend a hand ;)

Also picked up some "Tony" wheels and feet from www.richmondau.com (Thanks for the supplier Tony (AuS MaDDoG)). My feet are 90mm wide with an M12 bolt. The wheels are the S4448 model. See the catalog for specs.

Got my laser cut parts from Rick (rnixon) a couple of weeks ago. Nice bloke Rick. He was good enough to show me the monster MM he built. Great job. The photos don't do it justice.

I now have enough bits and pieces to start building. Just thinking about the best sequence to follow.

So much steel...

Hi Nick!!

Looks like you have plenty of work to get on with now :D

Cheers
Tony

Nick those beams might kill you but they sure will break and squish your toes. Just speaking from experience :) If you dont have some I highly recommend some steel toe boots.

...and a gantry crane to move them.

Let's see now..

1. Heavy steel ..... check!
2. Steel toe boots ..... check!
3. Gantry crane ..... hmmmmm ..... there must be forum for DIY gantry cranes somewhere .... :D

talk to Greg in AZ, he built his! *and it's really nice*

I bought these plans. $13 (USD).

http://www.synthx.com/shop/product_i...?products_id=4

A necessity for a one man shop. Good design and after its built, all the back pain goes away. Image that. :)

He's back. And this time he's serious... No really.
 

Well it's been a little while since my last post. Been busy with life, child No.3 and many other excuses.

All the while the steel I bought back in 2010 has been patiently waiting on the garage floor, taking up space and forming a nice layer of surface rust.:mad:

Well just before the new year I made a pact with myself (and with the Mrs) that I would finish this thing by April. So I have cleared my schedule and I'm back with the program.

If you see me slacking off feel free to poke me with a sharp stick.

Good for you mite.
Welcome back.
I have built mine and very happy with it too.
Prod, Prod !

Welcome back, Nick. Show the Mrs. some cool stuff you can build her, and she'll keep you motivated. :)
Good luck with your build.

Thanks guys.

Have been busy over the last month. Here is where I'm at.

The base (blue part) is all welded and I have done a loose assembly of the x beams and the cross bearers. Seems to fit together and is pretty square.

I guess the rail drilling/grinding is next.

Looks like you need to be moved to the "Construction Started" area.
Great job!!

Congratulations on your new home for your thread.