Firefly chassis repairs

Hi I am a new member restoring an early 1932 Firefly.  Does anybody have a sketch or details of the attachment of the circular member that joins the rear chassis together and supports the fuel tank. It appears to be somehow attached to the spring hanger.  The last inch or so before the chassis is heavily corroded, is it solid or a tube? Posted by FLYJCW 04/08/2015 17:13:35

Hi, I have a 1932 Firefly tourer chassis no. 9939.  Looking at this rearmost chassis cross member my best guess is:    A 13/16th in. diameter solid steel bar (based on it sounding solid when tapped!)    Heat shrunk into the chassis rails (there is no evidence of a weld)    Turned down at each end to take a 9/16th. castellated nut holding on the spring hanger. If you send your email address to  <!-- e --><a href="mailto:timedmunds@aol.com">timedmunds@aol.com</a><!-- e --> I will send some photographs. Good luck with your Firefly ownership. Posted by tedmunds 19/08/2015 13:02:16

Hy thanks for that I will email you.  I have ground away at it a bit and it seems that there is a solid bar in a tube on mine!  I am suspecting that the bar might go right across and the tube be a spacer to keep the chassis ends apart?? Posted by FLYJCW 19/08/2015 18:28:00

Well what an excellent response..... thanks Simon Fisher  Tim Edmunds and John Stubberfield.   All had their bit to add including technical stuff.  I have also now got copies of the Firefly Manual and spares catalogue. John has introduced me to the TVAM, The Vintage Alvis Manual where a lot of these problems and solutions are made clear.  The Spares catalogue proves my thoughts that it is a solid rod which provides spring mounting points at each end, with a tube to space the chassis apart....... amazingly the stay rod was 3 shillings and tuppence in 1933 and the tube was 2 shillings.... I probably won't get them for that price now.  However John's reading of the TVAM and experience of the task on his brothers 12/50 indicates that his is a brute force job as the bar welds itself to the eyes in the and of the dumb iron with corrosion.  Fortunately my bar is not very corroded and I have outlined a fix which restores the tubes integrity without undue violence.  Her is a sketch of what I propose.  Thanks to all who replied..... I will be back as my car is really a log book with parts attached! JCW Posted by FLYJCW 23/08/2015 18:17:26

So after a long absence caused by health issues and the Boxing day floods I am back on the job as from June 1st 2016!  The Firefly endured 32 inches of flood water on boxing day... well &quot;river soup&quot; really... but I figured after 84 years she wouldn't have taken much harm. The back axle revealed nearly a gallon of oil and water and the sump was over whelmed, the oil being lifted out all over the garage floor. I had just completed the gearbox rebuild and it was on the garage floor without its bottom plate and top.... the river and its sandy soup rose up through it so .... here I go again!   When I took the sump plug out of the engine the water rushed out with a central twist of golden Morrisons 20/50 oil a bit like an old fashioned Barley Sugar sweet in the water stream.  So on with the job... I had the chassis repair pieces folded up last year so the task was to cut out the rot and replace it with new.... some careful stress analysis has taken place and a repair strategy designed to retain strength and flexibility in the chassis. John Stubberfield made me aware of the &quot;Alvis Repair Manual&quot; and the method of strengthening chassis cracks...... in my case the &quot;dog leg&quot; splice in the offside rail section.  The front of that rail will be a butt joint in the cross member area using a &quot;Butt Strap&quot; and gussets as used in aircraft manufacture on such a joint.... more photos when it is done!   The Late Chris Compton advised me too on this project repair especially in respect of the engine / gearbox cross member which he advised me to repair in situ...... so sad he left us early.   In my dismantling work I am constantly amazed at how 84 year nuts and bolts easily undo but taper pins in the brake cross shaft ae very difficult to remove.  Some photos of progress are included...... oh and I made a Chris Compton style engine trolley to keep the engine on whilst the work progresses. Posted by FLYJCW 16/06/2016 19:32:11

My homemade engine trolley for Firefly engine. Posted by FLYJCW 16/06/2016 19:34:43

Well done John,  What an interesting journey. Is it possible to document the rebuild as you go and give us instalments in &quot;The Bulletin&quot; - it will make a great read?  The Australian climate is so much kinder on our cars. My TA21 still has the original chassis paint and there not a spot of rust.   Richard Melbourne Posted by RichardWallach 16/06/2016 23:16:30

Thanks Richard nice to hear from you..... I am envious of a chassis with paint on it!   I am collecting a lot of information, photos, sketches and drawings which I hope might be of some use in the future!   Here is a drawing of the handbrake quadrant.  I am investigating getting it cut out in stainless, with perhaps some spares, if it is economically viable, as it is similar on a number of chassis. If not I will paste the drawing onto the steel and cut it out model aeroplane builder style! Posted by FLYJCW 18/06/2016 08:58:28

Chassis repairs continue a pace......  The Cross member that supports the engine was a daunting task.... I decided to take advice and repair it in situ.  Cardboard templates are the way to go and I soon had a sense of how I could  rebuild it, the pictures show the process. I ordered a piece of 60mm x 60mm x 4mm wall square tubing and laboriously cut out the pieces I needed with by Black and Decker jig saw! I am now onto the nearside, carefully removing and replacing rotten metal to ensure things stay square.  Using doublers or &quot;fish plates&quot; to strengthen weaker areas.  The riveted joints are being welding and HT mushroom head bolts used to replace the rivets, they are fitted after being warmed up, tightened securely and spot welded for security.   Finally will be work on the front dumb iron on the nearside which has suffered collision damage at some time letting the axle travel backwards 1/2 and inch or so... porta-power and heat is the prescription.... the detail will follow!  JCW Posted by FLYJCW 11/07/2016 22:08:14

Here are some more pics of the repair process. Posted by FLYJCW 11/07/2016 22:14:10