View Full Version : Purchasable Tricks and Easy Fixes
nnfuller
27-11-2011, 23:42
So I have been helping budget for our next season, and I was thinking that maybe the CD community could help. I wanted to create a list of things that can help a team during the build season. My favorite example of this would be the plastic air tanks that arrived mid season last year. I was wondering if there were other links that solve common problems.
These problems might include but are not limited to:
Weight Savings
Chain Tensioning
Non-Traditional Gearboxes
Wheel Sources (Not Andymark or IFI)
Sensors
Tools
Thanks for the help!
Nathan
I have to warn you that there are many red herrings in any sort of list you'd get. There ain't no such thing as a free lunch -- but there are cheap lunches. For example, I'm willing to bet my BBQ pulled turkey lunch today that many, many hours were spent searching for an air tank that would fit the needs of a team within our rules before the white fiberglass ones were actually found. Many other 'tricks' (such as the Dark Soul Chain Breaker (http://www.chiefdelphi.com/forums/showpost.php?p=883436&postcount=18)) have caveats like "#25 chain is the ficklest $#*! chain you'll ever use -- 1 degree out of alignment or 1/4" too much slop and it's guaranteed to come off!".
That being said, the Dark Soul tool worked great until we lost it, heh. We're going to get a new one soon. The caveats: #25 chain is the ficklest $#*! chain you'll ever use. The sprocket teeth are so shallow that even the slightest imperfections in your robot production process will show up at the most inconvenient times.
If you need thin, strong boards that can hold the weight of a robot (like ramps for 2007), then honeycombed fiberglass may be a good fit. We've also use it for our electronics boards since 2007. This year we might use something different. The caveats: it shears very easily, so use wide washers at every mount point; it is not meant to be a structural member that can withstand impacts, so the weight it carries should be light during all interactive times of play.
Jon Stratis
28-11-2011, 14:26
I'll also caution you that any list you come up with may not be valid next year - rules always change. Last year was the first time those plastic air tanks are a prime example - last year was the first time they were legal. I know (from personal experience as an inspector) that they were a huge pain during inspections. Speaking personally (I have NO insight into the GDC or what they're thinking on the rule book), I wouldn't be surprised if that specific rule changes again this year to help make things run a little easier... It's just a nightmare for both inspectors and teams to trace those plastic air tanks back to specifications and show that they are rated for the appropriate air pressure.
Andrew Schreiber
28-11-2011, 14:48
Weight Savings - Freshmen with a hole saw? But there is no easy way of doing this, a lot of it requires you to do the math to figure out exactly what material you need and how much of it. Be very careful here.
Chain Tensioning - AM sells a chain tensioner that works reasonably well. You could also just design for an integer number of links between the wheels and be done with it. According to some discussion on last night's cast #35 chain will just deal with it.
Non-Traditional Gearboxes - Dewalts were pretty popular for quite a few years. However, in my experience, the majority of top tier teams use the AM guts with a custom housing. A few build completely custom ones nowadays but the need to do that is diminishing. As far as other sources. Banebots is TECHNICALLY a source but there are a lot of people on these forums that have some very creative words for BB transmissions.
Wheel Sources (Not Andymark or IFI) - Colson wheels. Literally worst kept secret in the NE region. Avoid BB wheels, they tend to shred. Probably would work ok for grippers though. Some teams have been going back to the old school pneumatic tires but they are by no means easy as interfacing with them has, traditionally, been a pain.
Sensors - Sparkfun Electronics. Incredibly support, reasonable prices, and probably the coolest shipping boxes in the industry. Most of their stuff is of decent quality, I've never had any problems with them. Just don't order resistors or leds from them, their prices are a little steep.
Tools - Can't help ya here.
Not really a list of easy fixes or quick purchases that will turn you into the next 254 but it should point you to some alternate options you can utilize in the future.
If you need thin, strong boards that can hold the weight of a robot (like ramps for 2007), then honeycombed fiberglass may be a good fit. We've also use it for our electronics boards since 2007. This year we might use something different. The caveats: it shears very easily, so use wide washers at every mount point; it is not meant to be a structural member that can withstand impacts, so the weight it carries should be light during all interactive times of play.
Corrugated plastic, properly supported by frame, is similar, but maybe a bit tougher. You still need the washers (the plastic crushes a bit), but it can take a pretty tough impact. 330 used it for ramps in '07.
Peter Matteson
28-11-2011, 15:28
Weight Savings - Freshmen with a hole saw? But there is no easy way of doing this, a lot of it requires you to do the math to figure out exactly what material you need and how much of it. Be very careful here.
We prefer the Unibit (aka stepdrill):
http://www.irwin.com/tools/browse/drill-bits/unibit-step-drills
These are safer and easier to use than hole saws when your holes are in the correct size range.
Tensioning is easy to do with various size delrin idelers. Just swap in different ODs to in crease or decrease tension.
sanddrag
29-11-2011, 16:55
Corrugated plastic, properly supported by frame, is similar, but maybe a bit tougher. You still need the washers (the plastic crushes a bit), but it can take a pretty tough impact. 330 used it for ramps in '07.As did 696 with great success. Good stuff.
Chris is me
29-11-2011, 17:23
A neat little known product: IFI sells pre-punched C-channel and gusset plate (http://www.vexrobotics.com/products/vexpro/ifi-frame.html) that basically looks like Vex on steroids. If I was on a team with a bit of cash and no mill, I'd certainly strongly consider it as a general frame material.
George C
29-11-2011, 18:34
We had great success with some new (to us) products last year:
Garolite sheet available from McMaster Carr. We used it for paddles on our gripper. Easy to work with, very strong and a lot cheaper than carbon fibre
Constant force springs available from McMaster Carr. Helped counterbalance our 3-stage elevator
Igus linear slides available from Igus. Used in our 3 stage elevator and our mini-bot deployment system.
I echo the comment on step drills, plastic air tanks and UHMW plastic spool and cam-type chain tensioners.
Surgical tube is wonderful stuff. Many strengths at McMaster Carr and elsewhere
Some great things we always use:
- echo the Dark Soul chain tensioner: We have 2 or 3. We always use seemless chain and hardly ever lose chains. (Not one all last season.)
-Surgical tubing: Used for counterforce, passively springing something, and battery straps(<-this works really well) among other things. We always have this on our robot usually serving multible functions.
-Polyurthane belting: this is the choice material for convayer belts such as 2009. However, it is also great for powering rollers in other applications and can act as a mechanical clutch if desired. In 2011 this powered our claw as well as provided the grippy surface for the tubes. It also allows for figure 8 belts which can make it better then chain in some applications. We also always have some of this on our robot every year.
-lexan: This has a variety of uses not the least of which is an electronics cover. We always use this for decorative body panels however, do to its flexable nature it is also VERY durable in the 1/8 - 1/4 size range. We also used 1/8 as the entire bottom half of our claw in 2011 and It never broke once. It is also quite light which makes it a pretty great building material in the correct applications. We definatly use this every year on the robot.
-velcro: its great for things that are often taken on and off the robot. We use it especially for bodypanels.
-Zipties: Especially the high strength ones. In 2008 we held togeather our elevator with zipties for the remainder of competion after it was sheared off by the overpass in elims.
-1"x1"x1/16" L brackets: You can't buy them, however its great to have a bunch pre-made. Every year we usually have a couple of these on the robot. They are also great for prototyping. The first thing freshmen make in the shop is always these, and they always seem to get used up.
Good Luck, Bryan
AlecMataloni
29-11-2011, 19:50
If you don't already use them, the Anderson Powerpole Connectors are a MUST HAVE for any team's wiring! They make replacing motors, speed controllers, and other important electrical components parts much easier, faster, and safer.
Here's a guide from the FIRST website related to them. At the end, it tells you where you can purchase the connectors and the related crimping tool. http://www.usfirst.org/sites/default/files/Anderson-Powerpole-Guide.pdf
Chris is me
29-11-2011, 20:49
If you don't already use them, the Anderson Powerpole Connectors are a MUST HAVE for any team's wiring! They make replacing motors, speed controllers, and other important electrical components parts much easier, faster, and safer.
We successfully received sponsorship from Anderson Power Products last season and got our connectors all for free. This has been more useful than I could have imagined. We have a single, asymmetrical electric "plug" on our robot with connectors attached to each other that allows us to remove our electronics board from the robot with one click. I would recommend it especially to teams without a practice set of electronics.
JamesCH95
29-11-2011, 22:51
If you need thin, strong boards that can hold the weight of a robot (like ramps for 2007), then honeycombed fiberglass may be a good fit. We've also use it for our electronics boards since 2007. This year we might use something different. The caveats: it shears very easily, so use wide washers at every mount point; it is not meant to be a structural member that can withstand impacts, so the weight it carries should be light during all interactive times of play.
The fiberglass laminate is awesome. It can be custom made too, with various skins and cores if one is so inclined.
To solve the bearing stress issues (fiberglass sheets are actually very strong in shear if laid up anisotropically) using a big washer clearly works, but a stronger solution is to epoxy the washer in place. Or better yet epoxy a bushing in place to prevent crushing the board. Smaller washers/bushings could probably be used if they are glued, to save weight.
Peter Matteson
30-11-2011, 07:31
A neat little known product: IFI sells pre-punched C-channel and gusset plate (http://www.vexrobotics.com/products/vexpro/ifi-frame.html) that basically looks like Vex on steroids. If I was on a team with a bit of cash and no mill, I'd certainly strongly consider it as a general frame material.
We have a mill and welding capability yet we use this on many of our robots to save time. FYI IFI calls it SuperVEX in house.
remulasce
30-11-2011, 23:55
Double stick tape was influential in keeping sensors, motor controllers, and joysticks attached where they should be, while also serving as a structural component in minibots and our "borrowed" minibot deployer.
Double stick tape was influential in keeping sensors, motor controllers, and joysticks attached where they should be
Yup try out 3m's VHB. It's real good stuff
http://solutions.3m.com/wps/portal/3M/en_US/3M-Industrial/Adhesives/Product/Bonding-Tapes/VHB-Tape/
Garrett.d.w
01-12-2011, 02:13
Yup try out 3m's VHB. It's real good stuff
How strong is 3M's VHB tape (on a scale of 1-10... 5 being duck tape)?
Is durability with this tape a major concern?
Oh... and has anyone tried to get this stuff donated to them before by 3M?
remulasce
01-12-2011, 02:29
The stuff is ridiculously strong. 9 or 10. The minibot deployer was mounted on a plywood base, which is what we taped (and bolted) to the robot. When we undid the bolts and tried to take it off, the plywood failed before the tape- there were large chunks of wood still stuck to the robot, where they had been ripped out of the board by the tape. For a quick and easy way to put together prototypes and then not have to worry when the "prototype" makes it into competition, the stuff is matched only by zip ties.
How strong is 3M's VHB tape (on a scale of 1-10... 5 being duck tape)?
Is durability with this tape a major concern?
Oh... and has anyone tried to get this stuff donated to them before by 3M?
This stuff is ridiculously strong, some of the stuff my kids have done to me for fun:
1. VHB'd the top lid of the toolbox, I thought for about 10 minutes that they had locked it. Silly me, they had VHB'd it shut!
2. VHB'd a sprocket to the tablet and put a small screw into it. Silly me, fooled again, VHB it was.
On a serious note, we have been using it more and more and we love VHB, its awesome stuff. Make sure to buy the real stuff and not the VHB knockoff/cheapo stuff they sell at Lowes or Home Depot.
-RC
Andrew Lawrence
01-12-2011, 09:45
This stuff is ridiculously strong, some of the stuff my kids have done to me for fun:
1. VHB'd the top lid of the toolbox, I thought for about 10 minutes that they had locked it. Silly me, they had VHB'd it shut!
2. VHB'd a sprocket to the tablet and put a small screw into it. Silly me, fooled again, VHB it was.
On a serious note, we have been using it more and more and we love VHB, its awesome stuff. Make sure to buy the real stuff and not the VHB knockoff/cheapo stuff they sell at Lowes or Home Depot.
-RC
Maybe I'm looking at the wrong thing, but the website said a roll was over $1,000. Please tell me that's not it.
A small word of caution: while it sounds great for many things, VHB doesn't sound like something you'd want to use to mount electronics. Electronics inevitably need to be replaced at some point and there's no good sense is using an adhesive that will rip the backing off of your spikes, victors, jaguars or digital sidecars. We had this problem when we tried industrial strength Velcro to mount electronics one off-season.
VHB does sound pretty useful though. Thanks for the tip.
Jared Russell
01-12-2011, 12:19
Maybe I'm looking at the wrong thing, but the website said a roll was over $1,000. Please tell me that's not it.
That is per case, not per roll. You can find rolls of name brand VHB tape for around $80 a roll from Amazon and other online retailers.
BrendanB
01-12-2011, 12:41
A small word of caution: while it sounds great for many things, VHB doesn't sound like something you'd want to use to mount electronics. Electronics inevitably need to be replaced at some point and there's no good sense is using an adhesive that will rip the backing off of your spikes, victors, jaguars or digital sidecars. We had this problem when we tried industrial strength Velcro to mount electronics one off-season.
VHB does sound pretty useful though. Thanks for the tip.
Second this caution! I'd recommend using zip ties for your electronics panel over nuts and bolts. So easy to install and take out especially when you need to make quick fixes in eliminations! ;)
PAR_WIG1350
01-12-2011, 16:18
Maybe I'm looking at the wrong thing, but the website said a roll was over $1,000. Please tell me that's not it.
Try digikey (http://search.digikey.com/scripts/DkSearch/dksus.dll?vendor=0&keywords=3m+double+sided+tapes&gclid=CIPy5eDl4awCFSxrtgodgWzKnw&adpos=1t2&WT.mc_id=Tapes%2C+Adhesives&WT.medium=cpc&WT.campaign=Tapes%2C+Adhesives&WT.srch=1&WT.content=text&type=Broad&WT.source=google&cshift_ck=E242D3C0-1223-4E31-A593-91DF4439BD92csr3RIJ5VX)
sanddrag
01-12-2011, 19:32
Any purchasable tricks for pneumatics? Any fancy little fittings or valves or parts that many may not be aware of?
Billfred
01-12-2011, 19:44
It's a dirty trick, but one I've used on two teams now: You run out of time before ship day, and the robot is still bare metal.
Solution? Tape.
Gaffer's tape is available in a whole lot of colors, and it passes undetected from about ten feet:
http://chiefdelphi.com/media/photos/33623
http://chiefdelphi.com/media/photos/36749
1618's all-black-everything look was easy; black gaffer's tape is available at any stage lighting shop. (We did paint the big panels, and just taped the rollers and angle aluminum.) For 2815's robot, we went online to findtape.com; for the garnet, black, and yellow on the claw, our total cost was in the $60 range shipped.
I'd still want to use paint if I have the time and resources, but this route is MUCH better than bare metal for my money.
Andrew Lawrence
01-12-2011, 19:52
It's a dirty trick, but one I've used on two teams now: You run out of time before ship day, and the robot is still bare metal.
Solution? Tape.
Gaffer's tape is available in a whole lot of colors, and it passes undetected from about ten feet:
http://chiefdelphi.com/media/photos/33623
http://chiefdelphi.com/media/photos/36749
1618's all-black-everything look was easy; black gaffer's tape is available at any stage lighting shop. (We did paint the big panels, and just taped the rollers and angle aluminum.) For 2815's robot, we went online to findtape.com; for the garnet, black, and yellow on the claw, our total cost was in the $60 range shipped.
I'd still want to use paint if I have the time and resources, but this route is MUCH better than bare metal for my money.
Best advice EVER! We thought duct tape would look obvious! Thanks!
How strong is 3M's VHB tape (on a scale of 1-10... 5 being duck tape)?
Is durability with this tape a major concern?
Oh... and has anyone tried to get this stuff donated to them before by 3M?
Contact local sign shops, many of them use VHB. They may have small leftover rolls that they might be persuaded to give you.
Duct tape and gaffer's tape aren't the same thing.
That's kinda the point of what he said.
Alex Cormier
01-12-2011, 21:43
Contact local sign shops, many of them use VHB. They may have small leftover rolls that they might be persuaded to give you.
That's a good point. Also those sign shops make some sweet vinyl decals to make robots look pretty nice. ;)
Billfred
01-12-2011, 22:07
That's a good point. Also those sign shops make some sweet vinyl decals to make robots look pretty nice. ;)
This too. We put our sponsors and schools on the arm this year, and it ran me around $15. (And nine SCRIW trophies (http://campl.us/gBVg) ran around $80.) Have the adults on your team ask around--someone is bound to know a guy who knows a guy. (All of 2815's work has been done through the company that does signage for my employer, meaning I rarely have to make a special trip to get the vinyl.)
A small word of caution: while it sounds great for many things, VHB doesn't sound like something you'd want to use to mount electronics. Electronics inevitably need to be replaced at some point and there's no good sense is using an adhesive that will rip the backing off of your spikes, victors, jaguars or digital sidecars. We had this problem when we tried industrial strength Velcro to mount electronics one off-season.
VHB does sound pretty useful though. Thanks for the tip.
Even though we mount our electronics with bolts into our belly pan, VHB wouldn't rip the backing off electronics. We used it to hold our radio in place and our camera when we we had it on for our first regional. Also used it on other electrical things for other projects. It will come off with some pulling if you twist first and then pull. It also leaves hardly any residue.
JamesCH95
02-12-2011, 08:32
Any purchasable tricks for pneumatics? Any fancy little fittings or valves or parts that many may not be aware of?
I really like the "wye" style fittings of various connection styles. In some cases are cleaner to package than a "tee" fitting and I believe they flow better than a "tee" fitting if that is a concern.
http://www.mcmaster.com/#push-to-connect-tube-fittings/=f6qut1
I am also a huge fan of manifold mount solenoid valves, another part I wasn't aware of until recently. They make pneumatics easier to install, have fewer leaks, and package nicely.
http://www.mcmaster.com/#aluminum-solenoid-air-control-valves/=f6qwyf
thefro526
02-12-2011, 09:03
Any purchasable tricks for pneumatics? Any fancy little fittings or valves or parts that many may not be aware of?
Plastic Air tanks from Pneuaire: http://www.pneuaire.com/reca44cuin.html
And I'm with James on the 'Wye' fittings, they're so much better than Tees in many applications.
Oh, and I've found that Automation Direct seems to have the lowest prices on Pneumatic Fittings and pretty good shipping. http://www.automationdirect.com/adc/Shopping/Catalog/Pneumatic_Components/Push-to-Connect_Pneumatic_Fittings_(Thermoplastic)
pfreivald
02-12-2011, 09:18
Plastic Air tanks from Pneuaire: http://www.pneuaire.com/reca44cuin.html
Sweet. We didn't use pneumatics last year, and I was just about to ask what plastic air tanks people were talking about!
sanddrag
02-12-2011, 09:42
I am also a huge fan of manifold mount solenoid valves, another part I wasn't aware of until recently. They make pneumatics easier to install, have fewer leaks, and package nicely.
http://www.mcmaster.com/#aluminum-solenoid-air-control-valves/=f6qwyfWhat exact brand and model of valves are those?
JamesCH95
02-12-2011, 10:03
What exact brand and model of valves are those?
When I've purchased the 1/8" size style A they've always come out as SMC SY3000-series components, an FRC favorite. Be sure to specify the "24V" option, they will then work perfectly with the solenoid control module on the cRIO. To be extra-sure on the make/model I call McMaster and double-check for these sorts of things.
SMC SY3000 components can certainly be had for a lower price elsewhere, such as Automation Direct like theFro526 says. It just so happens that our main sponsor has an open account with McMaster, so it is very easy from a 'red-tape' perspective to order through them. And McMaster's next-day delivery on everything for ground-shipping prices is a life saver during build season for us.
Sweet. We didn't use pneumatics last year, and I was just about to ask what plastic air tanks people were talking about!
Yea, I picked up 4 mid-sized ones last year but didn't get them soon enough to be able to use them. They offer an amazing weight savings over the "old" aluminum tanks.
Just remember to save the spec sheet. :D
Oh, they are also cheaper than the standard "KOP" aluminum tanks.
pfreivald
02-12-2011, 14:47
Yea, I picked up 4 mid-sized ones last year but didn't get them soon enough to be able to use them. They offer an amazing weight savings over the "old" aluminum tanks.
Just remember to save the spec sheet. :D
Oh, they are also cheaper than the standard "KOP" aluminum tanks.
What was the turnaround time? Should I order some now?
Garrett.d.w
04-12-2011, 04:05
We recently bought a few for ourselves and they took about 4 or 5 business days to arrive at our shop (I think).
These tanks are defenitly worth it. The weight and money savings on these things has allowed us to put a lot more of them on our preseason robot. The added air capacity helps extend our battery life and keep the performance of pneumatics consistent.
We recently bought a few for ourselves and they took about 4 or 5 business days to arrive at our shop (I think).Keep in mind that these tanks are growing very popular among FRC, so they may end up on back order in the future. (I think this happened to a local team last year.) If you're a pneumatics team, you may just want to buy them now. You can always use/reuse them later.
Andrew Schreiber
04-12-2011, 11:33
Keep in mind that these tanks are growing very popular among FRC, so they may end up on back order in the future. (I think this happened to a local team last year.) If you're a pneumatics team, you may just want to buy them now. You can always use/reuse them later.
Maybeh... there is always the ever popular theory of a robot that must be constructed utilizing only wood.
Just a reminder that last years rules may not carry over to this year and those tanks may be illegal again.
thefro526
04-12-2011, 11:41
Maybeh... there is always the ever popular theory of a robot that must be constructed utilizing only wood.
Just a reminder that last years rules may not carry over to this year and those tanks may be illegal again.
Eh, I think Siri's point still stands. They're not so expensive that you're really out all that much money if they aren't legal.
Or if you're worried about back order and legality, you can order them the Saturday of Kick-off.
Maybeh... there is always the ever popular theory of a robot that must be constructed utilizing only wood.
That way we could tell if she were a witch :)
Andrew Lawrence
04-12-2011, 11:56
That way we could tell if she were a witch :)
Burn her, burn her?
Burn her, burn her?
But is she heavier than a duck?
Andrew Lawrence
04-12-2011, 14:25
But is she heavier than a duck?
Well, I don't think I've ever seen a 120 lb duck before.....so.....I think that's a yes.
Well, I don't think I've ever seen a 120 lb duck before.....so.....I think that's a yes.
I've seen a duck that's heavier than a person!
OK, so it WAS in Holy Grail...
Andrew Lawrence
04-12-2011, 14:55
I've seen a duck that's heavier than a person!
OK, so it WAS in Holy Grail...
But that duck did decide people's fate. But they had to weigh the same as the duck, not lighter than or heavier than a duck.
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