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[JB]

I'm not sure where to post this Q so I'll start here.

Speed 700 BB with a gearbox, I don't need the box so need to remove the pinion, its a press fit on the shaft, no grub screw...
I've tried heating it up and applying force equally to both sides but no joy, I need a puller of some kind but where can I find one small enough..
any ideas...?

Ta
J.

[dodgy geezer]

If you don't want the pinion at all you can grind it off....

[JB]

If you don't want the pinion at all you can grind it off....

As I'm buying this motor off a friend I think he would like the pinion back, the gearbox is serviceable...
I did think about saw/file etc..!
I've sent him an email this morning...no reply yet, I'll have to wait for his response before attacking it with the cutting gear 

Thanks for the reply.

J.

[Dave13]

Hi
I'm not shore if this will work but have you through about freezing the motor and then heating the pinion up?

[tonyH]

Hi JB,

Some model shops sell pinion pullers small enough for the job. Model car enthusiasts use them to change ratios. I bought mine from Galaxy Models in Ipswich but try a local one first.

Tony

[JB]

Hi
I'm not shore if this will work but have you through about freezing the motor and then heating the pinion up?

Good idea ! why didn't I remember that trick..must be my age, I keep forgeting stuff, its in the freezer now...wonder how long I should give it at -18  
I'll leave it in an hour or so and have another try, need some bits from the model shop today that should be long enough..we'll see  

J.

Hi JB,

Some model shops sell pinion pullers small enough for the job. Model car enthusiasts use them to change ratios. I bought mine from Galaxy Models in Ipswich but try a local one first.

Tony

Now there's another good idea...I'll report back...later...!

[essex2visuvesi]

http://www.modelhelicopters.co.uk/acatalog/VarAccs_Tools.html

Items 5 and 6

Ive got the small one of the 2 and it works great

They are a good company to deal with as well

[JB]

I'm sat in car outside blackburn models now. Its in my hand going in now. See if I can get a result. !  J.

[JB]

Well..the result was...no..! I'm wondering as the motor is a 'special' of some kind the gear pinion is not intended to be removed...
my friend is having the 700 back, no sense in damaging a good motor/gearbox, I have another Graupner 700 anyway,
I'm just building up my stock of the necessary bits as I'm new to boats and hoping to run the MTB and Huntsman at Fleetwood next month, not sure if they will let me in yet

That little puller at Midland helis looks nice mind you, I've always wanted a pair of Z bend pliers too...both on the wish list now !

thanks for the suggestions  

J.

[CGAux26]

MicroMark here in the US sells small wheel pullers.
http://www.micromark.com/SearchResult.aspx?deptIdFilter=0&searchPhrase=puller

On something as small as your gear it's hard to heat it and then pull it before it cools again.  And you must not heat it above say 300F or the gear will lose whatever hardness is in it. 

The way we pull industrial gears that are shrunk on is to attach the wheel puller and screw it down tight.  (It may also help to wrap a cold, wet rag around the motor and its shaft)  Then heat the gear evenly around its circumference only (spin it while heating), avoiding heating the shaft.  If it the gear does not pop off, give the end of the wheel puller screw a sharp rap with a hammer.  That will usually move the gear.  If not it's cutting torch time.

Oh yeah, and wear hot glove and eye protection.  Good Luck.

[JB]

CGAux26

Thank you for your informative and interesting post, I have saved that for future reference.

I was concerned about heating the pinion/shaft to much and I don't know if I have or not, I used the small pencil torch shown in the photo below.

My friend who owns the Speed 700 does not want the pinion damaged so I will return it to him and hope it will still be usable with the gearbox, he's a electric glider flyer...F5B class... and has moved to brushless motors and Lipo's but still has the brushed motors/ESC's/Ni-MI batteries, I've persuaded him to let me have some of his unused equipment for a small fee...!

I have another similar speed 700 Turbo so I'll use that instead of the Neodym.

Thanks again  

J.
  

 

[More Coffee]

Alot of times these gears are put on via a close tolerance slip fit and "green thread locker"

My experience with the green stuff in industrial application usually result's in the destruction of the part ,nut,bolt,screw's ,etc.. via pliers ,torch,bolt cutters...there's no finesse to removing these gears I don't think.