pic: Andymark's New Product

[Elgin Clock]

Originally Posted by Elgin Clock

I understood the original concept, but what are the curved up tabs sticking out the sides for in this design?
I will refrain from my next comment about those tabs before I hear their purpose, since I assume they have one.

Originally Posted by Alan Anderson

I don't know if this is the intent, but they seem perfect as hooks for a rubber band on each side of the tensioner pairs.

Originally Posted by Andy Baker

Bingo... rubber bands or o-rings will fit on those hooks.
Andy B.

Ok. I can safely comment about those curved features now.

In our typical chassis designs, we run our chain in a very tight area between 2 metal plates. I'm concerned in our design (and in similar one's I've seen) that those tabs are sticking out way too much to be effective & not get snagged on those plates, or anything mounted inside those plates. (Bronze bushings, spacers, screw heads, etc...)

We had our frame spaced so tightly one year in terms of area between plates, that a rushed replacement socket head cap screw (rather than the original flat head screw) actually popped the chain right at the link in the finals match of a competition.

I love this design, but I'm just saying that if we were to use these, we would more than likely just use zip-ties, not use the rubber bands or o-rings (which I think will wear out even more quickly over a competition anyways and require more maintenence - even more so than the blocks themselves with the concerns Greg N. posted) & we would probably cut or shave those curved tabs right off.

Just a thought from someone with bad experience with a hardware vs chain matchup in a real world design application.

Of course, your results may vary.

[R.C.]

Originally Posted by MikeDubreuil

I'd like to make a suggestion for this thread and the AndyMark website...

I have been following the development of this product since the first CAD drawings were posted on CD. Now, I think I'm a fairly smart guy... college educated and a pretty good software engineer.... it took me a very long time to realize these would be used as a pair and tie wrapped together. Now I realize why everyone thought the idea was so beautiful in its simplicity.

Now for the suggestion... could you show a picture of it used on a robot? I think that would help people (maybe I'm the only one) understand how to use it and why it's so effective.

As for the picture of this thing in action, I will take one tomorrow and upload it and why it is so effective:

-Lightweight
-Cheap
-No maintenance
-Easy Removal (We wasted so much time taking the snap ones on and off).
-Can be left floating or can be made stationary
-No lubrication

Originally Posted by Elgin Clock

Ok. I can safely comment about those curved features now.

In our typical chassis designs, we run our chain in a very tight area between 2 metal plates. I'm concerned in our design (and in similar one's I've seen) that those tabs are sticking out way too much to be effective & not get snagged on those plates, or anything mounted inside those plates. (Bronze bushings, spacers, screw heads, etc...)

We had our frame spaced so tightly one year in terms of area between plates, that a rushed replacement socket head cap screw (rather than the original flat head screw) actually popped the chain right at the link in the finals match of a competition.

I love this design, but I'm just saying that if we were to use these, we would more than likely just use zip-ties, not use the rubber bands or o-rings (which I think will wear out even more quickly over a competition anyways and require more maintenence - even more so than the blocks themselves with the concerns Greg N. posted) & we would probably cut or shave those curved tabs right off.

Just a thought from someone with bad experience with a hardware vs chain matchup in a real world design application.

Of course, your results may vary.

The zipties don't wear really, you could ideally go 7-8 matches without even worrying about the zip ties. As long as you cut the ends of the zip ties off. If the frame is really too tight. We used only one of the blocks then. We mounted it in between and made it stationary. If you upload a pic of your frame. I could give you solution. We had this problem when we were using the mcmaster carr ones 3 years ago.

[Zflash]

Having used the snap idle version I know how those are pulled together in order to keep the chain properly tensioned. With this you either use ty wraps or o-rings. My question is how easy is it to get enough tension on the ty-wrap without having to use a ty-wrap gun since most chassis do not have the room for it.

[Aren_Hill]

I like the simplicity, but it puts too many things out of control for me, such as the slack between the two sides when the sprockets change directions would be undesireable in my opinion. Our method was swiped from 118 with nice tensioners that just involve tweaking a screw a little tighter. And the chain loops were stable and not whipping around all over the place.

the main reason they wouldn't work to well in our situation is the proximity to victors... so no whippage room was available, kinda cause the swerve drive. We may use them elsewhere though it looks like a solid product, congrats

efficiency wise ball bearing idler sprockets and pulling the drive/driven sprockets to adjust the chain wins vs sliding on plastic

[R.C.]

You could always tension these with a hose clamp if you wanted to.