Ivan’s Locost Build Diary No 3

31 July 2005

Hi All

Made my Suspension Brackets during the last week – used 50 X 50 X 3mm RHT. – about 2 m was enough with some left over for re-makes.

Tip: Make the first four brackets per Chapman’s book with slight changes for the RHT tube selected. – then set up your suspension jig and check that the brackets fit – you might find that you have to adjust the hole offsets on some of the brackets – I had to make two specials with the holes about 6mm further out than standard for the bottom front A-Arm brackets..

Bracket Making

Step 1 – Cut the required number of 40 mm lengths of the 50mm RHT (26 per the book) – I made less as I am changing the chassis brackets at the rear – more about this at a later date.

Step 2 – Clean up on bench grinder.

Step 3 – Set up drill press with a stop on the Drill vice (tubing off cut and clamp) per the picture so that each bracket will be drilled the same. And drill all brackets – NB: do this before cutting the end off the bracket as they flex if C shaped when drilling. – also make sure the seamed end of the tube is to the outside (RHS in picture) so final bracket will be un-seamed.

Step 4 – Cut off seamed face – I made a simple wooden jig bolted into the Cut-off-saw for consistency. – see picture.

Step 5 – Finish bracket of bench and angle grinder to remove swarf and round corners.

Suspension Jig

This took me three tries to get something workable – see photo – two mornings work lost – if anyone in Cape Town would like to borrow these or any other jigs that I might make at a later date when I am finished with them contact me – there will be no charge except I will ask for a R100 refundable upon return deposit and that you pick them up at my house.

The chassis is centralised on the work table (markout board) and lines parallel to the centre line drawn the right distance from the centre line. The jig is located vertically by spirit level and brackets spot welded to the chassis when everything matches which they don’t – I ended up widening the front track by 20 mm to get a reasonable match – I think this is a good thing as it should reduce understeer – something that seems to be a problem with these cars. Has anyone else found similar problems with location of the brackets which appears to have something to do with the location of FU1 and FU2 (well named!)? I have re-checked my chassis and they seem right in terms of the book.

Tip: If I made a chassis again I would re-plan the front end with parallel tubes from just aft of the FU’s. to the front and the right distance from the centreline.

Castor

Once the brackets are in place I will measure up and make the jigs for the front suspension arms to achieve the right castor angle as some say the book allowance for castor is wrong.

Thanks Dad

I would like to honour my late father whose workshop tools I inherited and who gave me the confidence and ability to undertake and complete a project like this. You will notice some strange wooden boxes in some of the photos – these were made by him more than 30 years ago and are amongst the most useful items in my workshop, serving as stands, seats, steps, temporary vice stands, places to nail things to whilst assembling, engine stands etc etc. An important part of their functionality is that they are big, heavy and strong enough to anchor most things clamped or nailed to them up to and including a Chevy small block.

Safety

I bought three pairs of safety glasses so that one would always be at hand as I can never remember where I put them down last and I might decide to skip wearing them if I had to search too hard – the same applies to safety gloves, I have several pairs lying around the workshop – also got a great deal on leather safety gloves – 15 pairs for R30 on special at Makro (Currently about R30 for 5 pairs – still a bargain) – I see them in the Super Markets for about R20 a pair.

Regards

Ivan