Hi, i was wondering which series aliminum and thickness is most viable for frc for subsystems like intakes or shooters. also individual components like swerve bellypan. we current have a provider that has 5457 and 5mm and i was thinking if we can use the plates for all of our parts this season.
we usually use 6061 aluminum in the following variants:
- 1x2 and 1x1 box tube (1/8in wall thickness)
- 1/8in sheet
- 1x2, 1x1, occasionally 1.5x1.5 and 2x2 angle stock
- occasionally billet stock, 1/16in sheet, and 3/16in sheet
Maybe we’ll eventually end up streamlining what we use, but who knows at this point
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5457 is intended for applications where corrosion is a concern, and it’s much weaker and more difficult to machine (because of its softness) than the alloy used most commonly in FRC, which is 6061. for parts where strength or hardness are a concern, 7075 is even better, though it’s slightly more expensive and requires more care in machining due to its hardness. I’d suggest 6061.
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5457 looks to be weaker than 6061 Aluminum. 6061 is the most common grade of AL used in FRC. The other common grade, 7075, is reserved for High performance parts such as Swerve main plates and shafts.
https://www.makeitfrom.com/compare/5457-A95457-Aluminum/6061-T6-Aluminum
https://www.makeitfrom.com/material-properties/5457-A95457-Aluminum
Generally I would not recommend using 5457 for most applications in FRC, but you might be able to use it in places where you don’t need strength such as a camera, radio or Main Breaker mounting bracket. If you do bring the plates into the shop, you should mark them as “Low strength”.
5mm is a reasonable thickness for FRC. 5mm may be appropriate for some gearbox plates (probably not with 5457 though). Many people end up with 5mm when they try to order 3/16 (The same can be said for 1/8" ~ 3mm and 1/4" ~ 6mm)
If you would like to use bent sheet metal parts 5052 is a pretty good alloy. 6061 and 7075 are what we commonly use but they do not bend well.
The two most common aluminum alloys used in FRC are 6061 and 5052, while 3003 and 7075 may be found on rare occasions.
6061
This alloy is easily extruded into structural shapes and easily machinable. The aluminum tubing and flat gusset plates sold by all of the common FRC vendors is usually 6061. It can also be found in a lot of other shapes, like t-slot extrusion (80/20), spline shaft from Rev, etc. It’s strong, lightweight, and reasonably low-cost. Additionally, its favorable machining properties makes it a strong candidate for manufacturing gears, pulleys, or, really, anything.
5052
While 6061 offers many great upsides, bending it is not very simple. That’s where 5052 comes in. This alloy has great formability and can be bent easily in a press brake or with a vice. It’s also very easy to weld.
3003
This alloy is possibly the easiest to form, but that means it’s also pretty soft. I’ve seen 3003 rolled to form the structure of a shooter or formed to conform around a game piece.
7075
This aluminum alloy has the highest strength-to-weight ratio, but also the highest cost of the common alloys. Normally used in aerospace applications, there are only very specific instances where an FRC team may choose to use this alloy. The most common is probably shafting. I don’t think any vendor offers a COTS part made from 7075. Don’t even try to bend this - it’s very brittle.
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Almost every single Vendor has 7075 products. Pretty much all 1/2" & 3/8" Hex Shaft you see is 7075. A lot of the COTS aluminum gears are 7075.
With the slow death of sheet metal robots, I think its near safe to say that 7075 is more prevalent than 5000 series aluminum in FRC.
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Frog Force gave a great presentation on material selection at the mentor conference. The slides are public:
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Agreeing with most and recapping the most common and recommended:
- 6061 for extrusions such as tube, channel, angle, bar.
- 5052 for bent pieces, plates, and gussets
- 7075 for high-stress parts like shafts and gears
I have seen plenty of 6063 on robots, mostly because it’s what you get at the hardware store or home center. It has the weaknesses of 3003 (made for corrosion rather than strength), is too soft for good machining (makes rotini rather than chips) and is brittle when bending besides.
6061 aluminum gears are known as “washers” or “spacers”. Or they will be after a couple of matches when the teeth break off. It does do better in pulley form.
7075 gears last quite a bit longer.
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5457 is between 5052 and 6061(see every other response) and 5mm is a very good thickness. You can definitely use a lot of this on your robot as I dont see 5mm aluminum breaking in many applications, although 5mm will be very heavy to do all of your plates, I definitely recommend using 1/8 or similar thickness plates of 6061 or stronger for a decent amount of plates just to avoid crazy weight.
Make sure that the temper of the aluminum is correct. 6061-T6 is what you should look for. For 5052, look for 5052-H32 or H34.
5052 is fine for weaker stuff like bellypans, as some sheet metal sponsors prefer to work with it. It’s also cheaper. 6061-T6 is generally good for anything above that.
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Yes! Thanks for the correction. I had blanked on any 7075 COTS parts until after I had submitted the reply and immediately I edited to add that most shafts would be 7075. 
Keep an eye out for the aluminum 6063 alloy, not to be confused with 6061. We can get 6063 rectangular tube locally, but usually not 6061, so we have to order 6061. The 6063 alloy is structurally weaker and is instead designed for better corrosion resistance and the ability to be extruded or anodized or otherwise surface treated.
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Also, I believe that SDS makes their main module plates out of 7075 for their main module plates (as I think they got bent in 2022 after big falls from the hangar)
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6063 is also very gummy and not as machinable. Avoid for FRC!
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Default to 6061.
If you need to make bent sheet metal parts, use 5052.
If you need extra strength and are willing to pay extra, use 7075. The main place most teams use 7075 is shafts (for example, the rounded hex shafts sold by WCP, Rev, etc. are 7075).
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