[jjarvis98]

I've been kicking around a DIY CNC for some time. I just happened by my favorite surplus store and came across some scrap aluminum. I was planning a wood build because of the price, but these look like a decent price. Anyone verify that these are a decent price compared to T-slot stock?

They're about 4" wide and 7' long. There are predrilled/tapped 2-3mm holes that you can see on the side. $6 each.

[PaulRowntree]

Just about ANY Al is cheaper than T-slot stock. What you need to decide is if the material is as true as new T-slot, and if you are prepared to do the drilling and tapping etc to make this as strong as T-slot.

Don't count on the edges of surplus Al; in my experience such metal often shows that it has prior 'experience' by dings and divits that prevent smooth running. As structural elements though, it comes down to a question of your willingness to work around what you have.

Check out the engineering sites to get a feel for the strength of Al vs MDF.

Cheers!

[JoeSixPack74]

Those are aluminum relay rack sides. I had one a long time ago. They should be pretty strait and about 1/4" thick. At $6 a piece that ain't bad.

Open Frame Aluminum Relay Racks

[PaulRowntree]

If Joe is right then you may need to use several of these together to get a strong enough frame or gantry. Back-to-back to make an I-beam? My relay racks from Bud are good at what they are meant for, but I don't think they were planning on CNC apps.
Cheers!

[jjarvis98]

I was probably going to get them for my frame and figure something DIY out for linear bearings. I just haven't been looking at stuff long enough to know if this is a good price for the metal.

[jsheerin]

I used to love going to the Purdue salvage yard. I bought a ton of electronic equipment from them when they were clearing out old stuff from the EE labs.

[jjarvis98]

I just picked up 4. Back to back they'll bolt together perfect for some I-beams. They're also stiff enough on their own that I may just turn them on their back and use them with a bearing as the linear axis.

They have a TON of CPU power supplies for $5 I think. Should make my DIY 24V PS relatively cheap.

One of the old guys working there stopped me and asked what it was for. Said I was the 2nd guy to come in for a DIY CNC project.