Grapple repair. Tough customer.

[DAN_IN_MN]

The customer is my 5 year old daughter! She spotted a toy robot that's joystick controlled that I had stashed. I knew it was broken as I had bought it at a garage sale years ago in that condition. With her prodding, I got it out and started figuring out how to rebuild it. This is a toy that as a kid, I probably would have given my eyeteeth to have!

Here are a few pics.

Here's the customer!




I didn't take any pics of the part before the repair. Here's the start of filling in what was missing.


Chucked up in the lathe. Had to use the 4 jaw which I don't have the correct mounting.


Another view of the part chucked up.


Some progress. The customer is biding her time with clothespins. Things always take longer than planned!


Off of the lathe needing the third glueing!

 

[Ray C]

Remember, now is not the time to think about pressure or performance anxiety :whistle:. (LOL)...


Ray

 

[DAN_IN_MN]

Cliant holding glued up part




Glued up part machined. I was surprised how true the OD of these parts were to the face. On the other hand, there being true to an injection molded part, there are a lot of tapered surfaces.


Foil used as barrier so the two halfs aren't glued together.

 

[Terrywerm]

Tough customer yes, but creating priceless memories!

 

[DMS]

Wow, I think I remember those things, and yes, would have given almost anything for one when I was a lad. Excellent use of shop resources by the way

 

[DAN_IN_MN]

Found another problem. There's a cracked gear. If you look closely, you can see the crack in the 12 o'clock position. I turned a collar in an attempt to keep the gear from slipping on the shaft. It still slips. The aluminum collar did tighten it up a lot though. I still have to clean up the collar a bit too.

Anyone know what type of plastic these gears are made of? I'm thinking of trying bonding the gear to the shaft.



Thanks for looking!

 

[DMS]

Most likely nylon. You may have a tough time gluing. Is the shaft "D" shaped, or is there some other way it was holding it on (or was it just a press fit)? If you can't glue it, and you don't want to re-cut, you may be able to scavenge another gear from a broken toy or appliance.

That got me thinking, if you have enough material left on the gear, you may be able to drill and tap for a set screw, and file a small flat on the shaft.

 

[DAN_IN_MN]

Most likely nylon. You may have a tough time gluing. Is the shaft "D" shaped, or is there some other way it was holding it on (or was it just a press fit)? If you can't glue it, and you don't want to re-cut, you may be able to scavenge another gear from a broken toy or appliance.

That got me thinking, if you have enough material left on the gear, you may be able to drill and tap for a set screw, and file a small flat on the shaft.

Thanks for the reply!

Yes, the material is probably Nylon!

No, the shaft is round and yes it was a press fit. There are the same type of gears in her Thomas the Tank Engine engines. I have a couple of gears that have split on those too. That is where the failed gluing attempt was tried.

I like the idea of scavenging!

I don't think there is enough material to put in a set screw. It would have to be a small one!

After I posted, I was thinking about knurling/roughing up the shaft to give the ID something to bite.

 

[churchjw]

Great project. Time with her is worth a lot. How about just making the gears? This would be a great project to try it on if you have not done it before. These people carry about every gear in the world if you want to order some. http://www.sdp-si.com/Plastic_Gears.htm and don't forget McMaster carries a good selection of gears.

Jeff

 

[Bill C.]

Most likely nylon. You may have a tough time gluing. Is the shaft "D" shaped, or is there some other way it was holding it on (or was it just a press fit)? If you can't glue it, and you don't want to re-cut, you may be able to scavenge another gear from a broken toy or appliance.

That got me thinking, if you have enough material left on the gear, you may be able to drill and tap for a set screw, and file a small flat on the shaft.

Check with a hobby shop for replacement gears. Good luck and a cute granddaughter.