# Drive shaft extension



## heatherw (25 Nov 2014)

Good evening everyone,

I'm new to this scary metalworking section, but I'm hoping someone on here can help me.

I need to find a way to extend a tiny metal rod, preferably without welding it, something that slips over the end and tightens with a couple of grub screws would be good. I've been told to look in Maplins for drive shaft extensions but I couldn't find anything. The diameter of the piece (if my eyes were reading the figures correctly) is 2.4mm and I need to extend it at least 5cm, preferably with a cranked handle on the end of it. 

Any ideas? Am I in the right department?

Thanks


----------



## CHJ (25 Nov 2014)

Yes you are in the right department, although folks will need to make sure of your dimensions a little more accurately than when spinning bits of wood.

How thick a diameter can the extension shaft be? For there to be material to take grub screws it will have to be 8 to 10 mm diameter.

Your 2.4 mm sounds rather thin for existing shaft.

Should be easy for someone to make for you but postage may be expensive.


----------



## heatherw (25 Nov 2014)

Good point about the grub screws, Chas. the other way would be to have a flat on the end of the original and superglue it on, but I imagine making a D shaped hole is not nearly as easy as making a round one. 

It's the handle for a music box mechanism that I want to adapt for another mysterious purpose. I could try to,get someone to weld it on, but it needs to be straight.


----------



## CHJ (25 Nov 2014)

Ok, for that purpose, epoxy or even CA adhesive will be more than adequate.
Can you make a sketch of exactly how long and how much cranked handle you need.
You could bend up a length of 2.5mm wire and just join it onto the end of existing shaft with a suitable short length of metal tubing.


----------



## Mannyroad (25 Nov 2014)

On Ebay there are M3 aluminium push rod extenders:

http://www.ebay.co.uk/itm/2pcs-RC-Model ... 58af93e0c7

These are used in model engineering. They are internally threaded (M3). If your extension could be 3mm rod rather than 2.4mm (piano wire- which modellers buy with a threaded end), this could thread straight into the connector and be studlocked in. For your 2.4mm shaft you could 'metal-putty' it into the other end of the connector. That way, if needed, the extension shaft could always be removed from the main shaft and re-studlocked back. 

Alternatively, modellers would silver solder two rods together coupled up by a short length of brass tubing, also bought from model shops. We use this method all the time and the tubing is very thin walled so doesn't make a thick joint.

Hope this helps.


----------



## Mannyroad (25 Nov 2014)

Even better, what about these!!! Perfect I think. :wink: 

http://www.ebay.co.uk/itm/2-Pcs-M3-x-25 ... 58b29d7074

Any half decent model shop will have suitable socket head (allen key) grub screws. The grub screws are often used for retaining wheel collects on piano wire of model aircraft undercarriage.


----------



## Racers (25 Nov 2014)

Cut out a connector from a electrical connector block.

Pete


----------



## Mannyroad (25 Nov 2014)

+1!! :wink:


----------



## CHJ (25 Nov 2014)

Racers":2pk2qo19 said:


> Cut out a connector from a electrical connector block.
> 
> Pete


Good lateral thinking.!!!


----------



## heatherw (25 Nov 2014)

That is sooooo helpful. I'm going to try the tube method first as I have some and I think it will be the most discreet; if that doesn't work then I'll work my way down the list.....thanks guys!


----------

