Battlebots
Would you like to react to this message? Create an account in a few clicks or log in to continue.

Battlebots

A new forum for battlebots enthusiasts, competitors, and fans.
 
HomeLatest imagesRegisterLog inBuilders DB

 

 Fluffy √2 rebuild for September

Go down 
+4
Dan Curhan
Cody
Sean Rubin
Will Bales
8 posters
Go to page : 1, 2  Next
AuthorMessage
Will Bales
ULTRA contributor
ULTRA contributor
Will Bales


People Skills : 6135
Registration date : 2009-03-15
Age : 31
Location : Miami, FL

Fluffy √2 rebuild for September Empty
PostSubject: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeMon Aug 10, 2009 2:44 am

So, Fluffy is getting a makeover for September! Fixed drum, new tooth design, new drum drive system, and some new electronics to try out.

The drum's that eXecutor destroyed at Nationals are going to be slightly machined down, hopefully, and will use new teeth, hopefully they won't break..

Fluffy √2 rebuild for September Pictur34

Fluffy √2 rebuild for September Pictur36

Fluffy √2 rebuild for September Pictur37

The new drum drive system, is pretty much directly stolen from Richard. Sorry! The inverted timing belt idea just seems like the best way to solve the problem! you can have any gear ratio, or distance between axles, you want, belt lengths permitting, because the teeth don't have to mesh! It's got built-in slip clutch, and, it's cheap! You make your own pulleys! It's also the only thing that really seems to fit inside of the drum. V-belts aren't flexible enough, Flat belts, ironically, don't come in the sizes we want, Chain is heavy and rough on the motor, and multiple timing belts probably would rip the teeth off just as easily.

The new electronics is referring to the drive of the robot itself. I was poking around at the beginning of the summer, trying to figure out what to do next, and found myself looking at R/C car components, once again. Tekin is a company that largely focuses on brushless motors now, but also has several brushed controllers. So, I emailed the president of Tekin (proof it's not a very big company when his email is on their contacts page!), and have gotten a discount, and some additional information about their controllers. They should, in theory, be far superior to the Banebots, but we will find out! We will be using their FX-R controllers with two of their 2500kv Rock Crawler motors. BEFORE the competition, we'll test the combination, and see if they are worth the extra cash compared to Banebots.
Back to top Go down
Sean Rubin
Prezerdent of Sexxi Cuddlemen
Prezerdent of Sexxi Cuddlemen
Sean Rubin


People Skills : 5913
Registration date : 2009-03-16
Age : 31
Location : Miami

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeMon Aug 10, 2009 11:16 am

this is gonna be so sick!! im excited to see this in action.
Back to top Go down
Cody
2000+ club
2000+ club
Cody


People Skills : 7784
Registration date : 2009-03-16

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeMon Aug 10, 2009 4:15 pm

ooooo brushless drive!!!
Back to top Go down
Dan Curhan
Admin
Dan Curhan


People Skills : 6339
Registration date : 2009-03-14
Age : 32
Location : Sarasota, FL

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeMon Aug 10, 2009 5:58 pm

the backstop for the teeth is a good idea - but what else is holding them on? you don't have it drawn in your picture...
Back to top Go down
http://666bots.blogspot.com/
Will Bales
ULTRA contributor
ULTRA contributor
Will Bales


People Skills : 6135
Registration date : 2009-03-15
Age : 31
Location : Miami, FL

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeThu Aug 13, 2009 2:19 pm

ya, they're older pics.. There are 1/4-20 bolts holding it together..
Back to top Go down
Will Bales
ULTRA contributor
ULTRA contributor
Will Bales


People Skills : 6135
Registration date : 2009-03-15
Age : 31
Location : Miami, FL

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeThu Aug 13, 2009 2:20 pm

Well.. I got bored last night, so I did this..


Back to top Go down
rjw
Chief Bottle Washer
Chief Bottle Washer
rjw


People Skills : 7737
Registration date : 2009-03-31
Location : Miami

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeThu Aug 13, 2009 7:21 pm

Cody Harris wrote:
ooooo brushless drive!!!

I believe he is still going to be brushed...the fxr is a brushed controller

So Will....the site says only 3S lipo??? is that what you will be running for the drive?

Also, which motors are the 2500kv...35,55.?????

Thanks
Back to top Go down
http://www.R2RCR.com
Will Bales
ULTRA contributor
ULTRA contributor
Will Bales


People Skills : 6135
Registration date : 2009-03-15
Age : 31
Location : Miami, FL

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeThu Aug 13, 2009 10:50 pm

yup, still brushed drive!

for motor, we're trying out the 35T version. they're not actually 2500kv, I was missinformed.. but they're 1730kv. it's not too bad!

For the controllers: turns out, that they can take up to 6S lipo, but not whilst using the BEC. the BEC can't take the voltage. So, as long as you have an external bec, you're good!
Back to top Go down
Cody
2000+ club
2000+ club
Cody


People Skills : 7784
Registration date : 2009-03-16

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeSat Aug 15, 2009 8:52 am

i guesssss i read that to quick lol
Back to top Go down
Will Bales
ULTRA contributor
ULTRA contributor
Will Bales


People Skills : 6135
Registration date : 2009-03-15
Age : 31
Location : Miami, FL

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeMon Sep 14, 2009 10:36 pm

So, we ordered all of the Tekin stuff, and installed it. Today, we put it all back together, running on the new controllers for the first time, AND THEY'RE AWESOME!!! I love the things! They're really small, and we got them at a discount so they only cost $3 more than the Banebots! And, they say, that they can handle 108A, we'll see.. But the crawler motors and these speed controllers are just the best thing since Banebots came out! I'll take some pictures of the inside tomorrow. There currently are only 3 problems: 1, There are wires all over the place. 2, we need to decide on a new battery, since the MEGABATTERY-O'-DEATH is a little overkill. 3, still haven't redone the Drum drive, or finish remachining the drum and making the new teeth. It should be pretty interesting..
Back to top Go down
rjw
Chief Bottle Washer
Chief Bottle Washer
rjw


People Skills : 7737
Registration date : 2009-03-31
Location : Miami

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeTue Sep 15, 2009 10:36 am

I look forward to some pics!! Sounds good
Back to top Go down
http://www.R2RCR.com
Will Bales
ULTRA contributor
ULTRA contributor
Will Bales


People Skills : 6135
Registration date : 2009-03-15
Age : 31
Location : Miami, FL

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeTue Sep 15, 2009 10:58 am

Question for everybody:

We're having a problem with keeping the pinions on the shafts. Any ideas on how to keep it from slipping?
Back to top Go down
rjw
Chief Bottle Washer
Chief Bottle Washer
rjw


People Skills : 7737
Registration date : 2009-03-31
Location : Miami

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeTue Sep 15, 2009 4:03 pm

will bales wrote:
Question for everybody:

We're having a problem with keeping the pinions on the shafts. Any ideas on how to keep it from slipping?

Are the pinions from 36mm bb gearboxes? 3mm shaft 540 motors?

If so, order the pinions for the 370 motor and drill them to a press fit??

We've been lucky that some motors that we used have shafts with flats or splines, but MOST of the pinions were still snug enough.
Back to top Go down
http://www.R2RCR.com
jeeves_m_d
ULTRA contributor
ULTRA contributor
jeeves_m_d


People Skills : 6023
Registration date : 2009-04-21
Age : 30
Location : Sudbury, MA

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeTue Sep 15, 2009 6:51 pm

Theres always welding lol!

but the 370's are the way to go
Back to top Go down
http://lsrobotics.blogspot.com
rjw
Chief Bottle Washer
Chief Bottle Washer
rjw


People Skills : 7737
Registration date : 2009-03-31
Location : Miami

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeTue Sep 15, 2009 8:05 pm

Unfortunately, all the aftermarket motors (that I've seen) are meant to be used with pinions that slide on and then get set screwed. most are slightly smaller in diameter, or shorter, longer or whatever.

Also, there can be problems with locating the motor centered on the gbox. we've had to bore and/or make locating bushings for some.
Back to top Go down
http://www.R2RCR.com
Will Bales
ULTRA contributor
ULTRA contributor
Will Bales


People Skills : 6135
Registration date : 2009-03-15
Age : 31
Location : Miami, FL

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeWed Sep 16, 2009 12:11 am

I've been thinking about some ideas:

1) heat up the pinion after you drilled a smaller hole in it, and jam it on while it's hot, hoping that it would shrink enough. I figured that it's so small that this wouldn't work well enough.
2) find a spur gear with a set screw in it.. That was hopeless..
3) Make my own pinions from stock that I bought earlier today. On the right track..
4) Buy a "D" broach.. THEY DON'T EXIST?! you can't buy them!
5) I'm going to try to make a "D" broach/punch. I bought brass stock, so I might have a chance at it. I ordered some 1/8" drill blanks, and I'll use my surface grinder to put a flat on it. then, somehow, I'll put a guide hole in the pinion, turn down the end of the broach/punch, and pray that it works.

That's the idea I've got right now.. If it doesn't work, I can always just put a small hole in them..
Back to top Go down
Cody
2000+ club
2000+ club
Cody


People Skills : 7784
Registration date : 2009-03-16

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeWed Sep 16, 2009 1:20 am

pssst epoxy
hahaha
Back to top Go down
rjw
Chief Bottle Washer
Chief Bottle Washer
rjw


People Skills : 7737
Registration date : 2009-03-31
Location : Miami

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeWed Sep 16, 2009 7:58 am

I assume tha the shafts are round with a flat on them?

Just buy and drill the 370's slightly smaller and press them on. (no heat required)

at under $2 each, get a few backups

Option 1
Back to top Go down
http://www.R2RCR.com
donsun




People Skills : 5506
Registration date : 2009-04-30
Age : 33
Location : Ridgewood, NJ / Atlanta, GA

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeWed Sep 16, 2009 10:35 am

will bales wrote:
Question for everybody:

We're having a problem with keeping the pinions on the shafts. Any ideas on how to keep it from slipping?

Green Loctite
Back to top Go down
http://www.enigmarobotics.com
rdubard
mega contributor
mega contributor



People Skills : 5904
Registration date : 2009-06-10
Age : 59
Location : Ransom Everglades, Miami, FL

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeWed Sep 16, 2009 11:00 pm

Adhesives are clearly the easiest, mostly cuz we already have pinions that kind of work. If we had a limitless supply of motors and or shafts, I'd say try this first, buuut, we dont.

Gear stock or the 370 replacement pinions present cheap alternatives, and if we can be satisfied with round holes pressfit around D shafts, it really shouldn't be that difficult to do (especially with the 370s). . . . .Um, assuming we can find a simple and effective way to hold the darn things while we drill 'em--maybe using some sort of 'jammed' planet gears? I dunno, open to suggestions.

Also, I've only kinda looked for this in Machinery's Handbook, and not at all online, so I'm taking the easy way out by asking here: Do any of you know of guidelines for pressfitting? Like, for a certain material outer part pressed over another material shaft of a given size, what should the hole size be, and how much torque would it withstand before slipping? (I'm guessing I could figure this out from basic physics principles and material properties, but I'm also guessing most machinists don't have time for that sort of crap, and so there's a quick reference somewhere)

And I'm guessing the reason "D" broaches don't exist is because it would be almost impossible to center them correctly.

Which presents another interesting machining question--how DO they make "D" holes anyway?

Always with the questions. . . it's like I'm LEARNING or something. . .
Back to top Go down
rjw
Chief Bottle Washer
Chief Bottle Washer
rjw


People Skills : 7737
Registration date : 2009-03-31
Location : Miami

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeThu Sep 17, 2009 4:10 pm

I'm confused with this D shaft stuff....???

Are you referrring to a round shaft that has a flat on it?


If so, then mike the round part of the shaft and compare to the bb motor shafts. reduce hole diameter accordingly.

The motors with flats on the shafts that we've used were the same size as the oem's...the flat was only maybe .010" deep and the pinions held without distorting or slipping.

The force required to press the pinions on should be about the same as pressing the old pinions on a bb motor shaft

Not much help, but it shouldn't be rocket science.

A drill or reamer should follow the existing hole...speed and feed can result in a larger than ideal diameter, so start smaller and work up ...checking the press fit as you go

I recommend buying a few spares.

Does will have a collet chuck for his Harding lathe?
Back to top Go down
http://www.R2RCR.com
Will Bales
ULTRA contributor
ULTRA contributor
Will Bales


People Skills : 6135
Registration date : 2009-03-15
Age : 31
Location : Miami, FL

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeThu Sep 17, 2009 9:05 pm

of course I've got collets!
Back to top Go down
rdubard
mega contributor
mega contributor



People Skills : 5904
Registration date : 2009-06-10
Age : 59
Location : Ransom Everglades, Miami, FL

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeThu Sep 17, 2009 10:30 pm

rjw- yeh, by 'D' shaft, I mean a shaft with a flat on it. The way Will was talking about it, I thought there was some reason we couldn't just push a pinion with a round hole over it (like it would slip or distort, perhaps), and so he was looking for a way to make a matching 'D' shaped hole in the correct location in the pinion.

I really don't think it's possible to make a matching hole, but like you said, it shouldn't be necessary anyway.

And, duh, I must really be losing it to not think of using the lathe with a collet to drill the holes!

The reason I asked about a reference for pressfitting guidelines was not so much for this one task, but for all the different times we have had to make a decision about how much difference there should be in the diameter of the shaft and the diameter of the hole--so far it's been trial-and-error, so I was hoping for a better way.
Back to top Go down
rjw
Chief Bottle Washer
Chief Bottle Washer
rjw


People Skills : 7737
Registration date : 2009-03-31
Location : Miami

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeFri Sep 18, 2009 10:17 am

rdubard wrote:

The reason I asked about a reference for pressfitting guidelines was not so much for this one task, but for all the different times we have had to make a decision about how much difference there should be in the diameter of the shaft and the diameter of the hole--so far it's been trial-and-error, so I was hoping for a better way.

The M-handbook has guidelines for different fits, but a lot can be found online as well.

Experience is your biggest asset, do not hesitate to contact people in the know. There are just too many different situations to list here in this thread.

Maybe we should start a Q & A thread on this subject in the technical section of the forum???
Back to top Go down
http://www.R2RCR.com
Will Bales
ULTRA contributor
ULTRA contributor
Will Bales


People Skills : 6135
Registration date : 2009-03-15
Age : 31
Location : Miami, FL

Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitimeMon Sep 21, 2009 11:59 pm

Fluffy √2 rebuild for September Pictur38
Back to top Go down
Sponsored content





Fluffy √2 rebuild for September Empty
PostSubject: Re: Fluffy √2 rebuild for September   Fluffy √2 rebuild for September I_icon_minitime

Back to top Go down
 
Fluffy √2 rebuild for September
Back to top 
Page 1 of 2Go to page : 1, 2  Next
 Similar topics
-
» Fluffy 2? It's still being built!
» Fixing Fluffy's Flaming Fault
» Rocco rebuild
» bar exam rebuild
» doomsday Rebuild 3

Permissions in this forum:You cannot reply to topics in this forum
Battlebots :: Team Update Pages :: RE Robotics-
Jump to: