View Full Version : Seperated 16T mod .7
Flybar-less
03-22-2008, 03:33 PM
My friend seperated a 16 tooth mod .7 pinion at B-Ham. No telling how long it has been this way. The main gear is fine even though the seperation is about a 1/4".
I have seperated 13Ts, anyone else have a larger pinion seperate?
Finless
03-22-2008, 03:42 PM
Not yet..... I heard this was a early problem with the pinion and newer ones were fixed?
Bob
I had a brand new 22T mod .5 pinion separate on me today. Chewed the crap out of the top of my main gear.
Guess I'll be going to mod .7 now.
-Aox
pcliftonjr
04-14-2008, 01:03 AM
I also had it happen to a 22T mod .5 pinion.
Paul
Mercuriell
04-14-2008, 02:11 AM
My 13t separated just after I got my 600 and last week found that my 14 & 15 .7s were both getting divorced - Loctited the 15 but the 14 broke when I tried to get it back together. Problem on the 500 is that the Hacker spindle isn't long enough to extend through the top bevel and got crooked over but no excuse on the 600 whcih has a counterbearing support.
stvjeep
04-14-2008, 08:10 PM
OK I'm a newb here, but by "separated" do you mean the pinion itself cracked, or that a gap between the pinion and the main gear appeared?
LITHIUMSTATIC
04-15-2008, 12:03 AM
OK I'm a newb here, but by "separated" do you mean the pinion itself cracked, or that a gap between the pinion and the main gear appeared?
The Mikado Herringbone pinions are two halves that have been pressed together.
Ticidytoc
04-16-2008, 12:26 AM
Man, a simple tackweld from a tig would solve this once and for all.
tack-weld –verb (used with object) to join (pieces of metal) with a number of small welds spaced some distance apart.
fireup
04-16-2008, 01:38 AM
Man, a simple tackweld from a tig would solve this once and for all.
tack-weld –verb (used with object) to join (pieces of metal) with a number of small welds spaced some distance apart.
Good Idea, I think I'm going to do that before I see the same problem.
OICU812
04-16-2008, 04:22 AM
Man, a simple tackweld from a tig would solve this once and for all.
tack-weld –verb (used with object) to join (pieces of metal) with a number of small welds spaced some distance apart.
Yup not exactly paranoid but I did the same thing to all my pinions, now regardless if they could have they never will now...
ShuNut
04-16-2008, 08:24 PM
Man, a simple tackweld from a tig would solve this once and for all.
tack-weld –verb (used with object) to join (pieces of metal) with a number of small welds spaced some distance apart.
Maaan why cant Mikado do this ? is it too much hassle for them :DOH? surely they're aware of the problem and are at least going to "do it" now............ aren't they ?
stvjeep
04-16-2008, 11:06 PM
Two halves pressed together? This is a design just asking for failure. Good thing I have access to a welder! Why not just make it from one piece on a lathe/mill? I actually might get the machine shop to spin one out for me. I need to get my Logo 500 or 600 first. Still can't decide which one to go for....
Funflyer
04-17-2008, 12:09 AM
Well if it's a herringbone then you can't just turn it on a lathe. You'd have to have a cnc mill or lathe. That's much more expensive so I'm sure that's why they just press the two halves together. But they should do a little more to secure them if they are failing.
stvjeep
04-17-2008, 07:46 AM
I agree 100% that they should do something about it. I'm sure they know about the issue. Mikado seems like a pretty solid manufacturer. I hear of very few issues from them.
The shop I have access to has high speed CNC machines. I'll have to talk to them about the Herringbone gear. I'm sure they are able to make one up for me. But I'm sure you are correct in that the cost will be high. Spot welding would seem the most economical alternative.
to machine the herringbone main gear you need a 5 axis milling machine.
OICU812
04-17-2008, 03:36 PM
for the record I honestly know of less than 10 reported total pinion failures in the time since they came out, regardless of tooth count. There have been likley thousands of them sold, so the ratio is not news breaking by any means, I know that it has been reported to Mikado. Recently I sent some pics of what I did as per a tac weld thing etc... we'll see what comes down the pipe, perhaps there is a different adhesive they may use etc I do not know, I do not think it is a huge problem to worry about and do not hesitate to fly because of it, when I myself had a 13 tooth seperate I was still able to fly as you still have half in tact pushing the gear, I did notice it and land within 30 seconds without issue. I have a few that are not tac welded on machines and I have been flying them and working just fine to.
stvjeep
04-17-2008, 06:19 PM
I imagine if this was a huge problem we would be hearing more about it. I talked to the shop today and they can make up some pinions for me but at the cost of over $50 a shot it's just not worth the trouble. I'm not going to worry about it.
buster1
04-17-2008, 08:51 PM
Shawn, you are welding your pinions - is it a given these pinions are going to come apart? I am using a mod.7 15T?
Mercuriell
04-18-2008, 12:38 AM
I'd be interested to see some weld photos as I have had 4 come adrift - I guess a couple of spots on the top of the pinion where the upper wraps round the lower would do the job
OICU812
04-18-2008, 04:31 AM
Shawn, you are welding your pinions - is it a given these pinions are going to come apart? I am using a mod.7 15T?
13 tooth on 10S is a huge strain, the material of the pinion itself to the sleeve is super thin. On 6S and 8S not even an issue, but 13T on 10S seems to be abit much, this is my reasoning for the tac on those. I have several others of different sizes with no tacs and zero issues. I have 6 rtf logos so I have been experimenting to say the least. ;)
OICU812
04-18-2008, 04:33 AM
Here are a few pics of the 13Ts' I did. All you are looking to do is to connect the exterior to the sleeve is all. I have only had a 13 tooth go on 10S, I have not seen a higher tooth count seperate myself. I also have two other "un tacked" 13Ts' on a 6S and a 8S machine and no issue with those.
Mercuriell
04-18-2008, 05:38 AM
Thanks for the pics Shawn - TIG sounds interesting - have to see if I can get on a course to learn how to do it !
LITHIUMSTATIC
04-18-2008, 07:17 PM
I know how to Tig Weld and my buddy has the stuff so I'm off the see him next week.
LITHIUMSTATIC
04-18-2008, 07:37 PM
Shawn,
Why didn't you tack it where the small pins show? It seams that would be a better spot.
Did this the heat change the size of the hole? Did you need to file the hole opening?
OICU812
04-18-2008, 08:20 PM
Shawn,
Why didn't you tack it where the small pins show? It seams that would be a better spot.
Did this the heat change the size of the hole? Did you need to file the hole opening?
Yea that might have been a better spot, thought about that later to but just dripped in some red, I don't think its a big deal it is not going anywhere, lol. You gotta be carefull to not leak or blead any metal into the bore, just put in a welding rod to keep anything from going inside, no filing for the two I did needed. Its easy to overheat and disform so just be gentle on the heat and if you have something to practice on find your heat and co ordination prior to this event. Again keep in mind for setups with not alot of tourque on 10S I really do not think it is an issue to even worry about. I highly doubt you would see the strain or heat on the shaft from that Tango Jeremy.