Hardened and chromed steel rod

[C JParticipant @cj88518]

[C JParticipant @cj88518]

I am restoring a vintage 50cc motorcycle and decided to also restore the rear hydraulic shock absorbers for which I can buy new seals.

But I need to replace the chrome plated 8mm damper rods too, as they are scored, and can only find one supplier of hardened and chromed steel rod at the moment at that size.

So I wondered what kind of steel the live steam boys use for piston rods?

The new damper rod also requires a thread on each end!!!

S Gears & Sprockets

[DC31kParticipant @dc31k]

Have you tried hydraulic ram suppliers and rebuilders? This material is their daily bread.

Alternatively, what about gas struts for toolboxes, hatchback car doors, etc.?

Once you get under the chrome, the rod is easy to machine. You could grind it off gently if you cannot turn it off.

[Chris Evans 6Participant @chrisevans6]

I buy hard chromed rod for hydraulic cylinder repairs from local hydraulic cylinder makers/repairers. My applications are for farm equipment so never as small as 8mm. Once you get under the chrome the rods machine easily. Prices seem to have risen over the last few years. You could maybe use precision ground steel rod and keep it oiled to prevent rust ?

[SteviegtrParticipant @steviegtr]

Or use stainless. Everyone seems to go for stainless spokes on the wheels. Not much side load on a shock, its all up & down.

Steve.

[C JParticipant @cj88518]

DC31K, I hadn't thought of hatchback struts for a material source! and I've got an old Golf?

[C JParticipant @cj88518]

Hi Chris,

Do you hold the rod with collets or can you just chuck it without the rod marking up??

 

Edited By C J on 19/04/2020 19:57:25

[Philip DParticipant @philipd]

Products

These guys are good, but they only use one delivery firm (which is expensive). They do allow you to organise your own courier though ..or if your local pop in

 

Edited By Philip D on 19/04/2020 21:03:44

[HopperParticipant @hopper]

You might be able to fake it with a bit of stainless rod, good enough for the kind of miles most restored tiddlers do.

What kind of 50cc bike is it? Pics?

[Paul LousickParticipant @paullousick59116]

Stainless rod is softer than chrome and will wear a lot quicker but may be OK. Just depends on how much use it will get.

Paul

[PeroParticipant @pero]

Price and availability may be the limiting factors, but 440 stainless may be preferable if opting for stainless. It is high carbon and harder and stronger than most of the commonly available varieties. It is also available as precision ground rod ( if that is a requirement ).

In chromed steel there is a lot of options available ex China and probably many other places as it is sold for guide rails for 3D printers and CNC machinery. Supply ex China ( Aliexpress ) may be problematic at the moment but some suppliers with warehouses may be able to help. Checking with local suppliers to confirm that they have the material in stock would be recommended.

Pero

[Ex contributorParticipant @mgnbuk]

8mm chromed bearing rod is available in shorter lengths from UK sellers on Ebay

More expensive than buying what is probably the same stuff direct from China, but you get it more quickly.

Whether or not it is a suitable grade of steel is another question.

Nigel B.

[Chris Evans 6Participant @chrisevans6]

Hi C J. Up to 1" or 25mm I use 5C collets to hold the rod, bigger stuff is usually in soft jaws in the three jaw chuck.

[C JParticipant @cj88518]

I managed to finish the rods today but had to anneal the ends first with a Mapp gas torch, and limited the annealing by sticking the ends of the rods through a piece of steel

[C JParticipant @cj88518]

.. and my bike is an Itom like in the attached pictures

Edited By C J on 18/05/2020 00:52:47

[Ron LadenParticipant @ronladen17547]

When I read 50cc I imagined a little moped but seeing your pictures that is a proper motorcycle, I love the top one, lovely.

I had not heard of Itom so did a search and found a bit of racing video, couldn't believe how quick they are…amazing.

Ron

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