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-   -   How to attach a metal hook to a timing belt. (http://www.chiefdelphi.com/forums/showthread.php?t=111067)

PyroKnight 12-01-2013 14:01

How to attach a metal hook to a timing belt.
 
Hi, our team is trying to attach a type of hook on to a timing belt without using glue (in our testing it proved too weak). It needs to be able to go around the belt as this will be constantly revolving around and pushing frisbees but it cannot be fastened from the bottom. We'd appreciate any suggestions, thank you.

nnfuller 12-01-2013 14:25

Re: How to attach a metal hook to a timing belt.
 
Do you need to use timing belts? Have you considered alternatives? I know for a while my team was considering these and #35 chain http://www.mcmaster.com/#catalog/118/1036/=l08izr
heavier yes, but far more robust. Anyone else have any ideas?

PyroKnight 12-01-2013 14:31

Re: How to attach a metal hook to a timing belt.
 
Quote:

Originally Posted by nnfuller (Post 1213697)
Do you need to use timing belts? Have you considered alternatives? I know for a while my team was considering these and #35 chain http://www.mcmaster.com/#catalog/118/1036/=l08izr
heavier yes, but far more robust. Anyone else have any ideas?

This looks interesting, definitely a consideration, more ideas along these lines wouldn't be bad. Thanks for the suggestion.

DonRotolo 12-01-2013 19:12

Re: How to attach a metal hook to a timing belt.
 
Perhaps a pop rivet would work

Kevin Sevcik 12-01-2013 19:52

Re: How to attach a metal hook to a timing belt.
 
Quote:

Originally Posted by DonRotolo (Post 1213857)
Perhaps a pop rivet would work

If all your pulleys are big enough that a pop rivet head won't throw your belt, I can see that working. You definitely want the head on the toothed side of the belt, though.

mdiradoorian 12-01-2013 20:11

Re: How to attach a metal hook to a timing belt.
 
Guys you can't use a pop rivet on a timing belt considering that there are grooves on the inside of the belt to the pulleys. I like the idea with the chain because it does not break and is a rigid structure.

Aroki 12-01-2013 20:33

Re: How to attach a metal hook to a timing belt.
 
Could you explain what the timing belt-hook with be used for? It's a bit challenging to suggest solutions without any idea of the constraints

mdiradoorian 12-01-2013 20:35

Re: How to attach a metal hook to a timing belt.
 
It would be used for a floor pickup mechanism. It would be after the floor pickup to the magazine. Also it would be used from the magazine to the shooter.

Aroki 12-01-2013 20:47

Re: How to attach a metal hook to a timing belt.
 
I would avoid floor pickup, (in my opinion at least) the advantage of being able to pick up from the floor is less than the difficulty of designing a mechanism that picks up and can also orient the frisbees, and the time spent doing that would be better spent making a good climber and/or a reliable shooter/loader robot. This also removes the need for a floor pickup to magazine mechanism

In regards to the magazine to shooter, I'd suggest:
1. Conveyor belt under the magazine made from surgical tubing or timing belts (with the teeth pointing outwards).
2. A motor with a bar that rotates around and each time pushes out the bottom frisbee into the shooter
3. A piston behind the magazine that pushes the frisbees out into the shooter

mdiradoorian 12-01-2013 20:55

Re: How to attach a metal hook to a timing belt.
 
We actually do have a system on orienting the discs, however when still need to figure out how the discs will move with our system. The chain idea i so far the better option Thanks nnfuller.

DonRotolo 12-01-2013 23:09

Re: How to attach a metal hook to a timing belt.
 
Quote:

Originally Posted by mdiradoorian (Post 1213912)
Guys you can't use a pop rivet on a timing belt considering that there are grooves on the inside of the belt to the pulleys.

Yes, of course, there is no way to modify the rivet head to make this work. Silly me.

RRLedford 12-01-2013 23:42

Re: How to attach a metal hook to a timing belt.
 
Quote:

Originally Posted by PyroKnight (Post 1213684)
Hi, our team is trying to attach a type of hook on to a timing belt without using glue (in our testing it proved too weak). It needs to be able to go around the belt as this will be constantly revolving around and pushing frisbees but it cannot be fastened from the bottom. We'd appreciate any suggestions, thank you.

Shoe Goo urethane adhesive will hold the hooks on, as long as you give it time to fully cure 48 hours. It has super tenacious grip and very high peel strength.
It also remains flexible after curing. so it can handle the flex of going around the pulleys, as long as they aren't super small dia.

If you want a thick coat, put it on in two applications, allowing 1st one 24 hours cure time before applying the second. If laid on too thickly. lowest level curing gets delayed from so much more piled on top of it. It cures by out-gassing volatiles, so keep in a well ventilated area during curing.

To check if it's done curing, just smell it. Stink means not done yet.
Sticks to most everything, as long as surface is fully cleaned.
Best all around glue you can buy.

I build custom roller skates gluing the skate plates onto carbonfibre reinforced soles of athletic shoes (no screws), and have skated one outdoor pair for 13 years with no glue joint separation.

Example: glue mounted indoor speed skates -


-Dick Ledford

mdiradoorian 13-01-2013 16:04

Re: How to attach a metal hook to a timing belt.
 
By having this glue on the timing belt wouldn't it break off the belt considering the repetitious bend when it comes to the pulley?

Jeffy 13-01-2013 16:17

Re: How to attach a metal hook to a timing belt.
 
Quote:

Originally Posted by RRLedford (Post 1214091)
Shoe Goo urethane...

+1. Or I found a glue called "E6000". I think it might have a bit more strength, but stays flexible too.

MrBasse 13-01-2013 16:19

Re: How to attach a metal hook to a timing belt.
 
If you still like belts, what's stopping you from grooving the pulley to allow a fastener to pass through? All it takes is a lathe and a little patience. You shouldn't need the full width of the pulley to grip the belt if it is just lifting the weight of a frisbee.

mdiradoorian 13-01-2013 17:51

Re: How to attach a metal hook to a timing belt.
 
Quote:

Originally Posted by Jeffy (Post 1214455)
+1. Or I found a glue called "E6000". I think it might have a bit more strength, but stays flexible too.

Here is the link for the glue and thank you http://www.michaels.com/E-6000%C2%AE...efault,pd.html


Quote:

Originally Posted by MrBasse (Post 1214456)
If you still like belts, what's stopping you from grooving the pulley to allow a fastener to pass through? All it takes is a lathe and a little patience. You shouldn't need the full width of the pulley to grip the belt if it is just lifting the weight of a frisbee.

that is true, however I want a system to be simple, easy to make and easy to repair if it breaks.

MrBasse 13-01-2013 18:01

Re: How to attach a metal hook to a timing belt.
 
Quote:

Originally Posted by mdiradoorian (Post 1214496)
that is true, however I want a system to be simple, easy to make and easy to repair if it breaks.

What isn't simple to make? If you have access to a lathe, simply chuck up a pulley and turn a groove. If you don't, a student can achieve the same results (although a little less pretty) with a file and some spare time.

What isn't simple to repair? You would effectively cut the teeth off the pulley in the center. So if you used a fastener with a .25 head on it, cut a quarter inch groove in the middle of the pulley teeth. The only thing that might fail would be a fastener and those are pretty easy to come by.

mdiradoorian 13-01-2013 18:49

Re: How to attach a metal hook to a timing belt.
 
Oh by the way putting a fastener in the middle of a timing belt would increase the chances of of the belt breaking even if i were to make a groove in the middle of the pulley. The reason how I know is that I have tried. By having a belt you need tension and tension stretches to belt and when you stretch the belt with a hole in the middle of it increases the chances of it tearing.

MrBasse 13-01-2013 18:57

Re: How to attach a metal hook to a timing belt.
 
A belt tearing is very dependent on the stress levels we are talking about. I'd hope hat there aren't a lot of forces involved in a frisbee conveyor, otherwise I would question the overall design.

Lisa Perez 13-01-2013 19:27

Re: How to attach a metal hook to a timing belt.
 
An alternative to lathing a slot in the pulley would be to obtain a non-flanged pulley whose width is smaller than the belt width. You could then fasten the hooks to the edges of the belts. You would, however, have to consider how to keep the belt centered on that non-flanged pulley.

xSAWxBLADEx 13-01-2013 20:46

Re: How to attach a metal hook to a timing belt.
 
Quote:

Originally Posted by Jeffy (Post 1214455)
+1. Or I found a glue called "E6000". I think it might have a bit more strength, but stays flexible too.

I use E6000 at work. It has a little more strength then "Super Glue", but not much more.

JesseK 13-01-2013 20:53

Re: How to attach a metal hook to a timing belt.
 
Quote:

Originally Posted by Aroki (Post 1213943)
I would avoid floor pickup, (in my opinion at least) the advantage of being able to pick up from the floor is less than the difficulty of designing a mechanism that picks up and can also orient the frisbees, and the time spent doing that would be better spent making a good climber and/or a reliable shooter/loader robot. This also removes the need for a floor pickup to magazine mechanism

Silly silly silly. This paragraph is wrought with ill-conceived notions of this game.

A robot which sacrifices a complex hanger in lieu of a good autonomous which nets the 4 floor discs into the high goal is more valuable than a robot which sacrifices floor pickup for a 30-point hang. (24-pt auton from floor + 10-pt hang > 30-pt hang). That said, a 6-7 disc autonomous is just as hard (IMO) as a 30-point hang, and only one robot on an alliance is eligible to pickup 4 discs in a single auton. Yet the point is that there's a very good case for pickup from the floor for 2 robots on an alliance.

There's also good discussion about whether there will even BE any upside-down discs.

(edit -- sorry for the thread hijack -- the OP should keep trying with their floor pickup endeavors, IMO)


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