Chains

[CalTran]

Originally Posted by PAR_WIG1350

I would imagine a large zip-tie would also work if the tension is low enough (with safety glasses in case of high-energy zip-tie failure events ).

I'd like to note that should you go with this then be ready to explain to an inspector what you're doing. I dunno if it was just the inspector, but boy did he give us some trouble in St. Louis for using zip ties...

[apalrd]

Originally Posted by DonRotolo

Slightly off topic: Regarding installing master links, has anyone used a pair of "pliers" (somewhat modified with hooked tips) that hook into links at the ends so the chain can be pulled tight enough to insert the master link?

akoscielski3: That explanation was fine, but on small sprockets it can be difficult, and often side access is tight near the sprockets. We used that technique for our #25 chain that's out in the open.

There is a tool like you describe. We use one like the "B" style on that page.

We also use the Dark Soul Chain Tool for 25 chain, and found an equivalent for 35 chain. We seam the chain outside of the robot, then put the axles and sprockets in with the chain in place.

[yarden.saa]

Originally Posted by apalrd

There is a tool like you describe. We use one like the "B" style on that page.

We also use the Dark Soul Chain Tool for 25 chain, and found an equivalent for 35 chain. We seam the chain outside of the robot, then put the axles and sprockets in with the chain in place.

We have both tools and are using them. the problem is to lock the connecting link - very small parts that need plier and hands but not enough space for the hands... I realized that our problem was the gap between the 2 sheetmetal, we had 5 centimeters gap but in other drivetrains that were posted here I saw a lot more.

[Karibou]

Originally Posted by apalrd

There is a tool like you describe. We use one like the "B" style on that page.

So THAT'S what that tool is used for! I saw something like that in our cart for years, but never had a clue what it was.


Our solution to working with chains in tight places was a set of small fingers (mine) and adjustable chain tensioners. I don't know why the design worked the way it did, so I'll try and dig up some pictures, but all you had to do was loosen or tighten a bolt at the end of the drive train (we used extruded aluminum, and the ends were left open) and it would move the axle/sprockets to pull the chain tight. The chain was initially seamed outside of the chassis and then put in at the same time as the sprockets and axles, but if it needed to be removed at competition for whatever reason, loosening the chains helped to make the masterlink more accessible - if the axles were close enough together, we could pull the linked section up through the top of the chassis and take off/put on the link with plenty of space.

I don't know how this would work for 4WD (shown in your picture) as opposed to 6WD (what we used), but I'm sure that something similar could be designed to suit your needs.

[Brandon Holley]

Originally Posted by DonRotolo

Slightly off topic: Regarding installing master links, has anyone used a pair of "pliers" (somewhat modified with hooked tips) that hook into links at the ends so the chain can be pulled tight enough to insert the master link?

One way I always worked around using a tool like this was to assemble the masterlink on a sprocket. You would pull the chain tight, and slowly rotate the wheel/sprocket to a point where the links could easily stay on the sprocket without much effort. Then assemble the masterlink with the chain ends on the sprocket, and poof.

Of course this assumes you have access to the wheel/sprocket, which we usually allowed for.

-Brando

[BrendanRadabaug]

in the photo attached you can see how we run our chains with a integrated supershifter on the sheet metal. to take out or replace the chain all we have to do is take out the screws that are holding the tension (red arrows in picture) and the chain has plenty of slack to get at a masterlink under the robot. the chain rubs on a circular piece of Delrin to reduce friction and noise.

[DonRotolo]

apalrd, imagine tool "B", but with pliers handles instead of a turn knob, that's what I'm wondering about.
Zip ties would be fine too, but I just hate to waste zip ties...

Yarden, now I understand the problem. One possible solution: Train a student on Master Links. Have them remove and install a master link several hundred times, in increasingly difficult positions, always with tools instead of fingers. I am thinking that with a lot of practice someone could get quite good at it.

Inserting the master link itself seems easy enough, if the chain is tight enough.
Then there is the cover plate - not difficult, but you cannot allow it to fall off.
Then, the lock clip. Practice that move a few hundred times and you'll get good at it.

Maybe a job for a freshman?