By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Allendale Jan 24th

Steering side tube

What steel?

All Topics | Latest Posts

Search for:  in Thread Title in  
martyn nutland28/11/2020 12:44:34
124 forum posts
7 photos

Hello Everyone

I want to make a steering side tube (drag link if you're American) for a vintage Austin Seven. Could someone tell me the grade of steel tube that would be safe for this purpose?

I know....look for an old one on the 'net'. But living permanently in France, as Brexit cometh, this is an increasingly unattractive option as I strive towards engineering self-sufficiency!

Thanks in advance and if it's not premature - seasons(?) greetings.


Maurice Taylor28/11/2020 13:11:15
167 forum posts
30 photos

Hi, Try to find a drag link from an old Land Rover or similar 4 x 4 and make one from that.


old mart28/11/2020 14:35:56
2503 forum posts
169 photos

If ends are to be brazed into the tube, then chrome moly tubing like Reynolds 531 would be best. The molybdenum in the alloy prevents cracking caused by the heat of brazing.

ChrisB28/11/2020 14:44:48
575 forum posts
192 photos

I would use seamless tube for something like that, chrome moly as mentioned or BS4T45 - both seamless and used for roll cages etc. T45 can be welded and will not require heat treatment post welding.

Stueeee28/11/2020 16:00:24
67 forum posts

I have cut and welded A7 draglinks before; they are made of quite a thick wall tube and don't appear to be anything fancy in way of material.

If you're going to use the factory "cup and cap" style ball joints you'll want to use 3/4" OD tube which will need to be at least 14SWG wall so that you can machine the 5/8" bore for the inner cup whilst leaving a seating at the rear end.

If you're stuck with metric sizes in France, you could use thick wall 20mm OD tube and skim the outer down to 3/4" at the ends to accept the outer cap and bore the inner ends to 5/8" for the cups.

martyn nutland29/11/2020 08:44:51
124 forum posts
7 photos

Many thanks all - that's exactly what I wanted to know. There's no brazing or welding involved but it's useful to be reminded that there needs to be enough wall thickness to create the correct I/D but, very importantly, leave enough metal for the seating that takes the pad, shims and spring behind the ball connection on the drop arm and steering lever respectively.

Thank you again. Best. Martyn.

Charles P16/12/2020 19:13:40
10 forum posts

I looked at making one but Tony Betts sells the whole thing, tube, cups, end caps and ball joints brand new for £75. It made the sourcing of a short length of the correct seamless tube uneconomic


All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Support Our Partners
Eccentric July 5 2018
Eccentric Engineering
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest