Motors Would you do this? - machine out 5mm shaft hole to 6mm?

[Westy]

As some of you may or may not know ... I ordered some 12 and 13 tooth Pinions for my Trex 600 and they are all 5mm shaft bore. my motor shaft is 6mm.

I was going to take it to my mates and use his lathe to machine out the bore to 6mm.

If I get it true by aligning it with a 5mm mandrel and then run a 6mm carbide bit through it .... do you guys think it will work? or will it be out of centre?

looking for some feedback or if someome has tried it.... let me know if it was successfull

 

[wolfman76]

i have done that to one of my pinions just used a drill bit and put pinion in vise grips drill bit centered itself due to whole already being there just made sure i went real slow till it started to go through... never had a problem with it being off center...

 

[llommel]

Wolfman is right on, take it slow & make sure the gear is perfectly flat & perpendicular to the drill bit when you drill it.
You should have no problem. What I mean by slow is, push the bit through slowly but turn the bit fast.

 

[Westy]

cheers guys. I will do that. i have done a lot of lathe work in my Diesel Mechanic years (15) but not with something so important (To Me anyway - Lol ... can you tell the passion ? " ohhhh ... who doesnt wanna hurt his wittle heli baby" HAHAHA

 

[Lee]

I would give it a go. As you said, line it up with a 5mm bit in the drill/lathe to get it straight, then swap out the bit for a 6mm bit and bore that sucker out.

 

[Tony]

As you said, put it on a lathe and center it with a 5mm shaft. Once centered, put in a 6mm bit and go to town. As long as it doesn't slip, you will be fine. If it does slip, reposition it and complete the drilling them test it for round with a runout gauge. If it's true, then it will be good for the heli.

 

[Westy]

Cheers Tony .... will do it tonight of tomorrow .... can't be bothered goign down to my mates right now!

 

[Tony]

Let me put it this way, I would do it on my drill press and it's no where near as accurate as a lathe. You should be just fine.

 

[Westy]

I have still got plenty of time .... most of my parts are still on route! ... so no big rush to experiment with the ratios just yet!

 

[wolfman76]

Drill press? Lathe me never heard of such things i just had a hand drill and vise grips.... Lol

 

[Slobberdog]

if you can use a stepped reamer, that way you would guarantee to be cantre.

 

[wolfman76]

You would be centered with a drill bit they are tapered on the end so it would be centered

 

[Westy]

oh no ..... I am sensing a Cave dwelling mouth breather here ... .ahahahhhahaha ..... vice grips indeed lol.

 

[wolfman76]

Sssssssshhhhhh!!!!! You got a problem with vise grips.... Lol

 

[breeze400]

You need some kind of clamp to steady the pinion! Outer wise it will chatter while your drilling it!

 

[Westy]

Sssssssshhhhhh!!!!! You got a problem with vise grips.... Lol

yep I do ..... tried it .... and total WOFTAM! .... wrecked the first one (3 to go) Will go with my original thought of the lathe and see how I go

 

[wolfman76]

Oh ok well worked ok for me had to drill out pinion on my 500 did not have any problems i made sure that the pinion teeth were in teeth of the grips so it would not slip on me...

 

[Graham Lawrie]

I would use the lathe if you have access to one, that way you can get the speed and feed right as well as alignment The backlash in the gears should allow for any possibility of play

 

[Tony]

Make sure when you are drilling metal that you are on the slowest setting. High speed makes for horrible control.

 

[Westy]

UPDATE:

Threw All three of my remaining Pinions with the 5mm holes into the lathe and it did an ok job ... not as good as a 4 jaw chuck could have, but hey, beggars cant be choosers!

now all of them are 6mm and have a little runout.... you can hear it in the heli on spool up .... but I have set up the highest point on the pinion with the clearance needed to run her.

Put my 12 tooth on and ran 3 batteries on her..... seems ok.... just a lot slower than I used to have! BAtteries and motor are not heating up anywhere near as much.