80/20 chassis
 

My team was looking into using 80/20 for our chassis this year, and we couldn't decide what sizes to order. Does anyone have suggestions for what size of 80/20 to use for the chassis and/or extremities?

If you worked with 80/20 last year and could summarize the purchases that you made into a basic "parts list" for getting started, this would be great.

We began looking into 80/20 earlier this season and have heard that about 1000 linear inches should be sufficient for a basic chassis. Can anyone confirm? What should we add? Which connectors/fasteners have been successful?

Thank you.

Re: 80/20 chassis
 

1000in is more than 83'. That's a lot of 80/20. 100in is more reasonable, but may not be enough on its own to building a complete frame.

Re: 80/20 chassis
 

Moe has used 10 series and 45 series 80/20 and Bosch extruded aluminum for the past few years. We found it worked well especially for assembling and testing functions, arms, lift systems, etc. But during competition you'll find the joints come loose. Just make sure your team tightens the bolts every time your bot comes back from the field.

For our major functions we weld Aluminum angle and tube. After this year we decided to weld the entire frame including the chassis to improve the rigidity of our bot.

You'll need about 300 to 350 inches in length for a basic box bot and some functions.

Good luck!

Re: 80/20 chassis
 

1712 has used 80/20 extrusion systems for 3 years. Search cd media for 1712 and you'll find some chassis pictures. The amount you need varies based on manipulators, etc but I'd be glad to elaborate more if you'd like. For connectors we use the smaller drop in t-nuts and hidden corner connectors. We used to use the plates, etc...less expensive but more weight/space. We purchase all of it from Mcmaster-Carr. Let me know if you want part numbers, etc and I'll get you some info.

Re: 80/20 chassis
 

Last year we used two 38" long 1020 (1"x2") in our drive.

In 2007 we used four bars of 1010 in our drive.

80/20 is best used sparingly, we don't use much of it outside the drive train. We don't bother with the fasteners. We just tap the ends (1/4-20) and weld it together. Its much cheaper, lighter, and stronger that way.

There is an ebay store that sells the stuff at good discounts. Although we have a supplier here in the Bay Area that gives FIRST teams a discount. Careful who you order from. The so called "80/20 suppliers" don't always keep 80/20 in stock as I have found out the hard way...

Re: 80/20 chassis
 

16 has used 80/20 for the past two years with pretty good success. See what they're up to.

Re: 80/20 chassis
 

our fork lift assemblie used 80-20 last year and for the strength that u get for it its way over weight... the kitbot s alot better... the 80-20 worked well for everything else go and is great for manipulator, lifts etc. we used 1" 80-20

Re: 80/20 chassis
 

We (The Bomb Squad) have used extruded aluminum for all our frames since 2003. We have always used 20mm x 20mm ITEM brand material purchased from the US distributor in Ohio. They offer a discount to FIRST teams.

The material is amazingly strong for its size and weight. As someone already stated, joints tend to loosen from impact but a good design can minimize that. I believe a bare frame can be made as light as any other construction with some practice. ITEM also has a lot of neat fasteners like slides and rollers that make arms and elevators easy to design.

The major issue of this construction is fasteners. To take advantage of the material we use "T" nuts with M5 screws to fasten everything to the frame from gussets to gearboxes. The advantages are no reduction in strength and the ability to slide structures for alignment and chain tensioning etc. The disadvantages are weight and cost. The ITEM "T" nuts cost a dollar each before discount and the 80/20 distributor I checked recently charges $1.25. We usually use two hundred or more a year initially and probably twenty-five more fall out during competition.

I really can't guess how much material you need without knowing a lot more details. We usually use four rails extending from front to back internal of the wheels to support the upper manipulator/drives etc. and then build a frame that tapers at the back to take advantage of our three wheel drive system. U shaped frames for ball pickup are more difficult to strengthen but we have done it.

I would get some material and build a box first and get a feel for the weight and strength and then go from there. You can always use the box for storage if it doesn't suite your needs.

Oh, I think ITEM and 80/20 as well as some other brands I have seen are equivelant but not always compatible between them.

Re: 80/20 chassis
 

We used Item material also 2 years ago, for the frame and ball shooter. It is great to work with, I recommend it, but note that we went back to the kitbot last year...

Don

Re: 80/20 chassis
 

Team 104 made our frame from the 8020 quick frame material and connectors. We literaly hacked and wacked our frame together. Held up well in the comp and was lighter than our past kit bot frames.

Re: 80/20 chassis
 

As previously mentioned 80-20 does have many different fasteners that do come in handy such as

which was used to attach a solenoid to it &

which we used to connect two pieces at 90 degrees
this is our 80-20 that we used

Re: 80/20 chassis
 

When I was on 100 we used 1010 80/20 in 2003 and 2004. Didn't have any strength problems.

Re: 80/20 chassis
 

Foot for foot, 80/20 aluminum isn't that much heavier than 1x1x0.0625-wall extrusion. The biggest weight difference is in the fasteners -- to stiffen the 80/20 frame, make sure you allocate enough of your weight budget for plenty of bolts. This year our lift overran it's original weight calculation by ~15% due to extra nuts/bolts that were added at the base.

We used 80/20 for our lift in 2008 and noticed severe torsional forces when the lift was high and everything was under stress. That said, I'll echo MOE's comments that the frame needs to be stiffened at the end of every match. Another option is to sandblast/clean off the outer coating, and weld it. Usually a local machine shop is willing to donate an hour for this if you time it correctly and plan in advance. Welding would significantly improve the stiffness of the frame. Even better, you could take a 80/20 'jig' in, bolt the frame to the jig, then the welders would have plenty of room to weld the frame joints together without worrying about having to lay out your frame, or warping as the frame cools.

Re: 80/20 chassis
 

Quick note on 80/20,

DON'T DROP YOUR NUTS!

80/20 is great but can suck at times....

Re: 80/20 chassis
 

I've been lobbying for my team to use 80/20 or other extrusion for a few years. We might use it this year, since (a) my employer uses a lot of it (we've literally built buildings and cleanroom support structures out of it), so we get a lot of leftover material, and (b) we're such a good customer that occasionally the supplier lets some stuff "fall off the truck". I think I've got enough basic stock so that we can at least prototype a frame with it this year.

Re: 80/20 chassis
 

Team 980 has used 80/20 for our robot chassis for years (1010 extrusion). Our six-wheel drive with Andy Mark SuperShifters goes together quickly. Getting proper tension on the chains is very easy. We use simply-machined phenolic bar stock as pillow blocks for the axles with fastener through-holes spaced at 2". Instead of the more expensive drop-in T-nuts, we use economy triple T-nuts. We haven't had problems with fasteners loosening: just put a bit of Lock-tite on the threads and torque them down.

Oh yeah, you can save some $$ if you buy from 8020 Inc Garage Sale on eBay.

We've already received 6 pieces of 1010 (36" length) for $50 (plus $16 shipping).

Re: 80/20 chassis
 

My team used 1 inch by 1 inch 80-20 last year. It worked very well and we had almost no problems with it. If you have a square frame make sure you put in supprts to keep it twisting, If you take a hit, some of the fasteners aren't strong enough to prevent it from twisting a little. I still think 80-20 is wonderful and my team loves it. We made a frame for a six wheel skid in the off-season with 168 inches of 80-20. It's always good to have some extra. We used a little less than 350 inches on our robots frame in the '08 season, but it was a swerve drive and required a little more aluminum extrusion.

Re: 80/20 chassis
 

Never heard of phenolic. At first glance it looks like a great material for an impact-resistant non-conductive electronics board. How easy was it to machine?

Re: 80/20 chassis
 

Team 2228 has used 8020 from the start. We almost always stick with 1010. (We did go to 1020 for our 2008 lift). As for fastners, we have standardized on 1/4-20 wherever possible to reduce the need for more tap sizes and tools (DFM). With respect to fastners we mostly use the economy nuts. They are far cheaper than other 8020 alternatives and weigh less. You would be surprised how fast nuts can add up on weight. For the bolts stock up mostly on the shortest two sizes. While it is nice to have a few of the longer lengths in most cases you find these too long and the bolt bottoms in the 1010 extrusion prior to the head pulling whatever tight. We carefully tighten and have had very little problems with loosening. Be sure to properly clamp prior to drilling or sawing for safety.

We have no welding capability at this point and with 8020 I am not sure we will pursue that for some time.

Re: 80/20 chassis
 

Very old-school material, used as an insulator before there was plastic (like, aaround 80 years ago). Also known as Paper Phenolic, it machines like wood. Not terribly strong in tnesion (as with wood) but super in compression and shear, with some lubricating properties for low-speed rotational bushings. Not terribly heat resistant, and has a distinctive odor when burning.

Re: 80/20 chassis
 

I discovered something interesting today...

1/4-20 carriage bolts fit perfectly into 80/20 extrusion. Sure beats those dumb fasteners...

Re: 80/20 chassis
 

I must be getting old....

I think phenolic was the only material used for printed circuit boards in the old days, 1940s-50s. It was everywhere on the old surplus electronic stuff we played with as kids.

Back to the 8020 chassis stuff....I bought the material for our prototype chassis at one of the local hardware/lumber stores yesterday, $20 for enough material the whole structure, it came in flat, laminated sheets, and was grown naturally. Still looking for a good use for 80/20.

Re: 80/20 chassis
 

I really prefer to use the word "experienced" over "old"...;)

Phenolic is a class of materials: modern examples are Micarta and G-10 (Garolite at McMaster-Carr). Phenolic materials are durable, easily machined, have great mechanical properties, and cheap.

There's a lot to be said about materials selection in mechanical design. Using the right material can simply the design, making fabrication/assembly easy and repair almost unnecessary.

Re: 80/20 chassis
 

We use 80/20 for all of our fall warm-up projects and the BunnyBot competition. Depending on the competition, we build our FRC robots out of 80/20 1010 extrusion or 80/20 Quickframe, or some combination as well. Quickframe is about half the weight of 1010 extrusion but more of a pain to work with.

At the beginning of this thread there was a question about what to buy to get started. Here's my take. I’d say you could build 80% of a robot with just these 80/20 parts:

1010 Aluminum extrusion. I’d get at least eight 8’ pieces. More if budget allows.
3375 Drop in Nuts (100+)
3376 Drop in Nuts (100+)
3382 Econo nuts (200+)
3395 Anchor fasteners (100+) Drill press required.
4119 2 hole corner bracket (10+)
4101 4 hole corner bracket (10+)
4136 4 hole inside gusset bracket (10+)
4080 5 hole T plate (10) drop this if your budget gets tight.
6110 5/32” T handle wrench (5+)
6000 3/16” T handle wrench (5+)
6160 10 series counterbore cutter (cuts holes for 3395 fasteners.) Drill press required. You might get two in case you break one in the middle of the build season.

A nice assortment of 1/4 -20 socket head cap screws. Especially ½”-1”. You’ll also want some ¼-20 Button head cap screws especially around ½” and 5/8”. Obviously you can get these locally from a good hardware store or from 80/20. Which you use depends on your discounts. Some 80/20 distributors give nice discounts because 80/20 offers deep discounts for FIRST teams.

If you run into weight problems you can get 80/20’s Quickframe pieces for parts of your robot. Keep in mind that 80/20 1010 extrusion weights about .5 lbs a foot so it adds up fast. Quickframe is about half that.

As was mentioned before, you really do need to put Loctite on your bolts or use Nylock nuts when possible. The frame will shake itself to pieces after a match or two without it.

Team 1540 was the #1 alliance captain and won the Oregon Regional last season with a Quickframe robot. The previous year we were also on the #1 alliance and ended up as a finalist with an 80/20 based robot. The point is that you can be very competitive with this material and let students have the satisfaction of building the robot entirely themselves without knowing how to weld.

Re: 80/20 chassis
 

Team 1539 has used 80/20 for a few seasons, i think its about 3 so far, and have decided to work our way away from using it as much as possible. I will say that it is good metal, and easy to work with, but the only problem that we ran into was how heavy it is, because the (1"x1") weighs about a pound a foot. Otherwise, it works great for manipulators, and etc. (personally I would suggest using it sparingly)

note: small scrap pieces work as great pendants on necklaces (not that I made one for myself or anything :D )

Re: 80/20 chassis
 

I do not mean to be rude and correct you guys, but I know from many years of working with these materials that 1"x1" 80/20 Alum is 24.6" per lb. Where as 1"x1"x.0625 wall Alum extrusion is 48" per lb.

I also want to warn anyone who is machining phenolic that the dust created by machining it is very toxic to your lungs if you breath it in.

Re: 80/20 chassis
 

If you are not sure exactly what size/length of 80/20 to purchase I recommend going to a Pennsylvania company called Kodyn (www.kodyn.com) who makes a version of aluminum extrusion EXACTLY like 80/20 but it is a much smaller operation. They also make fasteners that I believe are much better than the 80/20 counterparts. Dave, the owner, is willing to take drawings and even hand sketches and will let you know how much material you will need and will even precision cut it to length for you. Tell him Matt from Quasics sent you...

Re: 80/20 chassis
 

Drawing up the whole whole robot in advance is good advice for teams on a extreme budget. However, what we like about 80/20 is it's flexibility to change your mind. You can bolt things together, get a better idea, and change it quickly without cutting out and splicing welded pieces. It's fabulous for prototyping.

To do that you need enough material on hand to play around. 80/20 1" extrusion costs only $.23 an inch list price. The FIRST team price, if you can find a distributor who will do that for you, can be 35% or more off of that. The expense generally comes from all the special inserts, bolts, brackets, etc.

I'm not sure the exact numbers but I think the cost to 80/20 distributors for material destined for a FIRST team is 45% off of list. They then may add a bit for their handling of your order.

Re: 80/20 chassis
 

I think what JesseK meant by in his first post was 1"x1"x.125" wall tube is roughly the same weight as 1010 80/20 extrusion. We came to this conclusion after taking two equal length pieces of both stocks and weighed them both. The difference was roughly .250-.5 lbs per 8'.

Re: 80/20 chassis
 

I once had a job assembling 8020 structures for a distributor and have used it since then on many other projects. We also built a robot out of it back in 2002 so i feel i speak from experience.

8020 Pros:
You can very quickly prototype things and move them around. It doesn't need welding which is a huge plus if you don't have good access to a TIG welder. This and the fact that we got it for free were the reasons we used ut. If you want to be able to move things around then use brackets or anchor fastners. Keep in mind the weight of brackets. If you want something thats strong and don't plan on moving it use end fasteners. Even if your not making a frame out of 8020 they make some very nice parts that come in handy. For a FIRST robot frame i would reccomend 10 series if you are designing in inches or 25 series if you are metric. 15 series or 40 series is overkill. 8020 is a great material and certianly makes for flexibility. In a fast paced design challenge like FIRST this is useful.

8020 Cons:
An 8020 Structure will be both heavier and more expensive than an equivilant welded structure from square or round. You have less freedom with wall thicknesses and there is a lot of mass concentrated in the center of the profile which does little for stiffness. It is particularly week in torsion. Keep in mind the weight the fasteners add.

Drop in T-nuts are your friend. get plenty of these. If you plan on using end fastners , get the jig so that you can drill the clearance holes painlessly. Thre is a fixture for milling the holes for anchor fasners but you don't really need it. Make sure you have a few ball allen wrenches in the appropriate size.

Also there are some older threads about this topic if you dig em up with the search

Re: 80/20 chassis
 

Our team used it last year and all of it was graciously donated by a local company (I think).

We made the mistake of bundling up like 1x2 or even like 2x2... If you don't make that mistake it will be an amazing building block.

I recommend it.