Anyone lost thier BaneBots Carrier pins?

[MrForbes]

it's my understanding that the pins on the replacement plates are shorter than the originals....has anyone tried simply taking the pins out of the original plates, and putting them in the new plates?

maybe that's too easy....

[Richard Wallace]

Originally Posted by squirrel

it's my understanding that the pins on the replacement plates are shorter than the originals....has anyone tried simply taking the pins out of the original plates, and putting them in the new plates?

maybe that's too easy....

I think the problem is not short pins, it's over sized holes. The pins do not interfere sufficiently with the holes, so they walk out under load. Fatter pins won't work because their diameter has to suit the planet gears, so the only fixes are to (1) remake the plates or (2) somehow retain the pins in the existing holes; some have suggested using Loctite, others spot-welding. The latter has proved reliable enough for one event, so far.

edit: I have heard one additional suggestion. Since the pin holes are actually tapered, larger on the gear side of the plate, it might be possible to press them through so that they extend on the opposite side and thereby make the fit more secure. Then the plate could be installed "inside out". Don't know if that would help -- the spot welding idea seems better to me. /edit

[MrForbes]

are the pin holes tapered before the transmission is put to use? maybe they get tapered as the pins move around?

anyways, the pics I saw of the new plates show the pins are not pressed in all the way, and I believe this is because the pins are too short. every team has(had) the original long pins...don't cost nothin to try them....

[Richard Wallace]

On the spare carrier plate subassemblies I saw at St. Louis (AFAIK there should be spares available at each event) the pins were pressed in flush with the back side of the plate. We tested one by applying light hammer force to a punch and it popped right out. We gaged that hole and measured that pin diameter, and concluded that at least some of the holes have insufficient interference fit to the pins. It is true that the measurement of hole taper was made after removing the pin, so that may have had some effect; however, the same taper was apparent in a "new" part and in one that had failed after short use.

[sanddrag]

I noticed the new plates have a letter stamped into one side (was it a K ?). Does anyone know what this means?

Anyway, this may be the perfect application for Loctite 680 retaining compound. It is great stuff. It took a torch and an arbor press to get off a gear on a CIM that was a slip fit on that had a drop of that stuff on it. Just make sure surfaces are relatively clean. (no grease).

[Teched3]

BuzzRobotics, Team 175, has been on this potential problem of loose pins on the new carrier plates. We have been using the original carrier plates, and have only suffered minor distortion of the double D drive hole. We are only using a single CIM with sporadic use of the Banebot in our secondary drive, so we are not expecting trouble. But to prepare for the future, we anticipate installing the new hardened plates. To prepare them, we are installing 4 mm X 16 mm hardened dowel pins into newly drilled - reamed holes for a good press fit, and then resize the length to the original carrier plate pin length. We don't feel loctite will stand up in the oversized holes, and are afraid of distortion from welding. In the meantime, the new Banebot transmissions will have a 2nd revision of the carrier plates already installed when they become available, according to a conversation with an engineer at Banebots. If you make new holes, you could use the pins from the original carrier plate that are the proper length, if you can't obtain new pins. Make your own choices.

Why is there never enough time to do it right, but always enough time to do it again???

[Ben Piecuch]

Hodge,

I'm a little confused with what you're doing with the trannies... As I understand it you're doing the following:

- Using the replacement carrier plates, but discarding the pins
- Drilling New Holes for new dowel pins
- Rebuilding this modified carrier plate with new pins?

Is this correct? Also, you said that there is a possibility that Banebots is shipping out ANOTHER revision to this carrier plate? (I haven't heard anything of this...)

Personally, I like the tack welding idea. Now, if I can just find someone in the area who will do the welds for us (we don't have any welding ability/knowledge...)

BEN

[Teched3]

Originally Posted by Ben Piecuch

Hodge,

I'm a little confused with what you're doing with the trannies... As I understand it you're doing the following:

- Using the replacement carrier plates, but discarding the pins
- Drilling New Holes for new dowel pins
- Rebuilding this modified carrier plate with new pins?

Is this correct? Also, you said that there is a possibility that Banebots is shipping out ANOTHER revision to this carrier plate? (I haven't heard anything of this...)

Personally, I like the tack welding idea. Now, if I can just find someone in the area who will do the welds for us (we don't have any welding ability/knowledge...)

BEN

Hi Ben,

We are modifying the new hardened plates with 4mm holes drilled and reamed in between the existing holes for the pins. We can't use the original pins as they are in the robot presently, so we got new pins at Atlantic Fastener ($0.31 cents each),but they have to be shortened 1 mm. As Banebots discussed with me, the holes are tapered from laser cutting, and the finish reamer didn't get to some of the surface. therefore, only an edge of the hole is holding the pin. Because of this "slop", I'm afraid welding will take the pin out of square with the plate, and Loctite doen't fill voids. Last time I tried to use the TIUG welder in school, it didn't work well at all. I could try welding your pins with MIG. If you made a collar longer than the pin, and a clamp that would allow access to weld, we might keep the pin perpendicular. Want to try?

With respect to the transmissions that will be coming, Banebots tells me they will have a 2nd revision hardened plate in them with properly sized holes. They are also considering putting tie bolts from the mounting plate corners to hold the plates square and tight to the tranny housing. The 8 screws don't presently do a good job of this.They cannot offer just the revised plates, as the manufacturer will not provide them. Looks like you will have to buy the whole transmission assembly to get it. That could change after the season, as time is short, and they are trying to meet the demand for Nationals. Who knows, by next year, they may have square holes and a square end on the output shaft as shown by Joe Johnson in some posted drawings, and make these transmissions the standard. Stick with these guys as they are willing to listen and make changes.

[Elgin Clock]

Finally got a chance to post a pic of our solution to the Version 2 carrier plates we received at the competitions, but which still gave problems:

http://www.chiefdelphi.com/media/photos/27573?

We welded in the pins on the version 2 replacements in NJ, and it worked like a charm. (for now) - See picture - This picture I uploaded will be only the first of an ongoing series of reports dealing with these I'm sure...

Oh, and Ben, if you need some welding done, let me know and I'll see what my team can do.
I know we have welding capabilities at our HS.

[BBnum3]

Team 1816's Banebots transmissions failed in Semifinal Match 2-2 at Wisconsin.We were running the kit transmissions with the 2 CIM adapters. When we opened up the transmissions we found that 9 out of the 10 pins in the two plates had fallen out. We were 1-0 in the semis and were looking to win the second match, and going to the finals. Banebots cost us a chance at a regional victory.

[Jacob Plicque]

Team 86 had its Banebot Transmission to fail during the first match of the finals at the Florida Regional. We were in a pushing match with both 1902 and 179. We have not disassembled the transmission but we suspect the pins came out. As near as I could tell five (5) teams had Banebot failures at the regional. We will update this after the autopsy.

[zander_108]

Originally Posted by Jacob Plicque

Team 86 had its Banebot Transmission to fail during the first match of the finals at the Florida Regional. We were in a pushing match with both 1902 and 179. We have not disassembled the transmission but we suspect the pins came out. As near as I could tell five (5) teams had Banebot failures at the regional. We will update this after the autopsy.

At least you were still able to deploy your ramps, Our transmissions broke as well, and we were not even able to compete against your alliance like we were originally supposed to.

[jskene]

Does anyone know the length of the older pins? I am thinking of buying some spare pins and having them welded into the transmission for the next competition.

[technoL]

Hopefully we will "lose" everything BaneBots in a few weeks. Going through 6 transmissions and losing a regional because of it is no fun.

(We still had fun, even if we didn't get to play in the finals and came in second)

[MrForbes]

I measured one to be .586" long. that's 14.9mm

here's a lousy pic of an old plate on a new plate, you can see the new plate's pins don't reach the top

Thanks 1212 for the photo op, but I sure wish you had not had so much trouble, it looked really frustrating.