PDA

View Full Version : Aluminium Profiles



wizer
07-03-2010, 06:59 PM
Hi Guys

I am trying to translate an American CNC plan by CNC Router Parts (http://www.cncrouterparts.com/product_info.php?cPath=24&products_id=49). It uses the 8020 Imperial extrusions. Is this stuff freely available over here? I have found this site (http://www.aluminium-profile.co.uk/acatalog/Aluminium_Profile_with_10mm_Slot.html) which sells similar profiles (are they the same?). 1530 8020 is 1.5" x 3" which converts to about 38mm x 76mm. The nearest size on that site is 40x80mm. Should I round up and use this? In which case, to follow the plan, would it be best to 'make it up as I go' when working out the lengths of each piece (using the US plan as a guide)? Or should I redraw the whole model and take the measurements off that?

Any help at this stage would be great. I'm completely new to CNC and struggling to understand, which is why I've selected a plan instead of my own design.

Cheers

Lee Roberts
08-03-2010, 10:05 AM
Hi,

Yes you will need to go for a close match when using the metric profiles, if you can do it i would redraw the model and then work from that.

8020 do have an eBay shop on the ebay.com but you will need to confirm shipping with them as they dont do UK shipping BUT will if you email them first.

Lee

wizer
08-03-2010, 10:08 AM
Thanks Lee. I've been going insane trying to get my head around al this. I think for my first machine I'm going to go with a small wood/MDF build and then upgrade when I have clue what I'm doing.

mel_earp
08-03-2010, 12:25 PM
I'm not ready to build yet, but have been doing lots of looking around and contemplating. I rejected the CNCRouterParts plans for many reasons, not least of which they are based on the Imperial profiles. It isn't just a matter of the cut lengths. If you look carefully, for example, the spacing of the mounting holes on the carriages are imperial to fit the 8020. If you were to buy the carriages ready made (from them) then they wouldn't fit metric profiles. And these 6 skate carriages don't look that easy to make without metal machinery, which I haven't got. The four skate carriages on angle look a lot easier to make, but being at 45 deg are not as easy to mount. I just wish I could find a simple way of mounting supported round rail onto aluminium profile - any takers on that one?

bogstandard
08-03-2010, 02:16 PM
If you need metalwork support Mel, my shop and myself are at your disposal, so don't worry about things such as that.

Bogs

mel_earp
08-03-2010, 05:07 PM
Bogs: That's very kind and very much on keeping with your helpful pages on model building. We'll talk about that when I visit. However, we shouldn't hijack wizer's thread.

Back to his subject: I seem to daily oscillate between "I'd really like it to be aluminium, 'cos they look nice and they are better and...." and "I ought to learn on something cheaper where I can makes mistakes and have the tools to cope". About 70% of the time I am down for building it in MDF to start with, keeping in mind what I want at the end so that I can re-use components. I do quite like the philosophy of build one to build a better one, especially when it's going to be the mechanics that get me.

Despite getting some bad press, I find the BlackToe stuff really useful, especially to video build that he has done.

wizer
09-03-2010, 10:00 PM
I completely agree Mel. My main hobby is woodworking. I have a 'shop full of woodworking machinery and so working with MDF is a 'known quantity'. Metal\Alu has never crept into my regular work and I've done very little with it, ever. It makes perfect sense to build from metal to maintain the highest amount of rigidity. But metal generally costs more (if you don't have contacts or experience) and is much harder to work with. Aluminium profile take away some of that complexity but for a price. Also, I can't help looking at all these '8020' builds and thinking it's a wast of good profile. It seems like 90% of that stuffs usefulness is not used. Having a profile which has four sides and up to 6 channels and generally you only put 2 bolts in each end. Maybe I'm wrong? Despite my comments, I'll probably go with alu profile on my second build because other types of metalworking is not something I can do. Thanks for your help on this but I think for my first one I'm going to stick with MDF. Although I might add some angle profile to some of the edges to firm them up.

mel_earp
09-03-2010, 11:49 PM
You seem to be describing my thoughts right down the middle :-). I especially agree with the comments about the profile. At £20 a metre for a big enough section, the costs very quickly mount up. A full BlackToe takes not much more than £20 worth of MDF - but the ready cut kit is expensive.

wizer
09-03-2010, 11:53 PM
I think I will use the green moisture resistant MDF when I do mine. Mainly because it's nicer to work with. Deciding on MDF was the easy bit. Working out the mechanics and electronics is driving me loopy ;)

ptjw7uk
09-03-2010, 11:58 PM
I have thought that it may be a half way house to build a router out of MDF clad in 1mm aluminium sheet but just looking at the price of ally sheet may as well get the profile in the first place!

Peter

daveshorts
10-03-2010, 11:41 AM
aluminiumwarehouse.co.uk is quite cheap, though I am not sure what you are trying to achieve by cladding MDF in aluminium. At 1mm thick it isn't really going to add to the strength and will be a bugger to get flat as it is flexible to an annoying degree.