Contraptor

We are working on a extruder. However that being said we are working on a lot of different things. You can get the steel if you want but you touched on not having the clean angle. Which in CNC accuracy is everything. Perhaps it wont be an issue. But I think it will be tough getting stuff "aligned". I am not sure our designs will work with that material either.

We should be getting our first fabbed angle soon to put into the contraptor store. So you do not have to make it you can get directly from us. Also, we are soon going to be selling laser cut center punch templates for all contraptor parts. This should help with the accuracy problem in making contraptor. As for expense. :/ Have you check onlinemetals? Its quite a bit cheaper than the home depot route.

Ril3y

Hi Hephyyc,

Different heads on different sides of the gantry is a great idea and should definitely work. I think milling wood/plastic on mini CNC it not a problem, however I don't know about milling aluminum - I personally haven't tried it - if I do, it will be in very shallow passes (thousandths).

AL angle is indeed expensive in Home Depot, but at OnlineMetals.com you can get it for about $0.8/ft.

As far as the angle you found, there are several things to note:
1. Hole spacing - for a construction set based on perforated beams, it's very desirable that the hole spacing be equal to the beam side, so for 1.5" angle you'd probably want 1.5" or 3/4" spacing.

2. Steel vs aluminum - the aluminum choice was made for several reasons, including smoother finish, better machinability, lighter weight, more accurate geometry (it's almost perfect 90 degrees) - based on the materials that were available to me in the local home depot at the time (which could be different elsewhere). Then I also searched online to find better alternatives. The closest thing in steel that I found was 1" perforated steel tube - which can be a great supplement and/or replacement for some structural components in Contraptor assemblies.

3. 1.5" vs 1" - there are also several reasons, in the end it boils down to the cost and availability of materials that make up the components of the set - tubes for sliding elements, plastic for pads, etc.

Cheers
Vitaly

You're right - good machinability is subjective and depends on tools/experience, what I meant to say was it's easier to work aluminum if you only have simple tools - vise, hacksaw, power drill.

I think you could put together a frame from 1.5" or 1.25" steel angle and then find holes to attach Contraptor angle with linear motion components. If your aim is specific project, it would save some drilling time. Your punched/folded angle is probably square - the one I saw in home depot was rolled and noticeably less than 90 deg.