Monthly Archives: December 2023

Time to fabricate the camber adjusters for the rear suspension – twice.

These connectors attach the top control arm to the yet to be fabricated rear hubs. once they are fabricated, the rear suspension components can be assembled and used to help determine what the hubs will look like. A short length of high strength threaded rod needs to be welded onto a bushing tube.

My first attempt did not go well, welds were messy and alignment was not good. I needed some practice so I made up practice pieces using scrap 3/4″ tubing rather than threaded rod. I tacked them together ready for welding. The two on the right are made with the bushing tubes salvaged from the first attempt!

The lathe is instrumental once again! The weld area is tapered and everything is aligned in the jig for tack welding.

In order to fully weld the practice pieces I clamped them upright in a small vice. In this orientation I could weld half way around the tube without interruption. I set the welder heat higher than the metal thickness recommendations and the results were very good. Time to move on to the camber adjusters.

Tacked and fully welded. I’m very happy with these welds, you can see the heat marks left on the inside of the bushing tubes.

I made a set of suspension side plates that match the hole spacing in the drawing and a couple turnbuckles to take the place of shock absorbers. Now the rear suspension can be assembled around the differential and drive shafts and some serious thinking about the rear hubs can take place.

Having the rear suspension assembled is very useful, it allows investigation of suspension clearance with wheels, establishing position of the hubs etc.

Flying with the bicycles for the winter.

I hope these wishbones fit! What we call control arms the Brits refer to as wishbones and now that they are all fully welded time to see how the front ones fit and time to attach the brackets for the back ones – twice!

The first order of business was to center drill all the bushings to 1/2″. Ultimately the bushings will be drilled to 3/4″ there will be a crush tube (with a 1/2″ id) that will go in the bushing. For now the 1/2″ hole will locate the suspension arms accurately without the need for the crush tube. I used a small arbor press to put in a half bushing on one side of the bushing tubes. These press in “snugly” and will need to be forced out so having one end of the bushing tube open makes that a lot easier.

I pressed an old ball joint into the lower front control arm, threaded the top ball joint into the top arm and put it all together on the car frame. This is looking very interesting. The control arms were to match the dimensions in the book but the BMW spindle is different than the book’s donor car. Hopefully there will be enough engagement of the threaded upper ball joint into the control arm.

I assembled the front suspension for the drivers side and everything checked out there as well.

At this point the rear suspension mounting brackets had not been positioned and welded ton the frame. Since the differential differs from the doner vehicle in the book I could not just use their locations.

I created a couple hardboard templates to show the locations of the bracket center lines. I could clamp these onto the frame,align them with the center line of the driveshafts and mark the location of the brackets.

This worked out pretty well to align the brackets and control arms except for one small problem…

The upper control arm extends too far from the frame because I welded the brackets on the side of the upper frame member rather than the bottom surface (Arggghhhhh, I hate it when I do stuff like that…). Well I will have to think about this for a while, I have other things to do.

I decided to go with 16 ga. steel for the floor pans of the Locost. It is heavier than aluminum but it’s stronger and can be welded onto the frame. The added weight is located as low in the frame as possible. Rectangular sheets were measured marked and trimmed with the angle grinder.

While I was getting ready to weld the floor pans I discovered an issue with the welder . A ceramic spacer in the nozzle was chipped so I made a trip to Everlast and picked up a couple along with a enhanced ground cable. I made a few passes around both of the floor pans stitching them until they were continuously welded onto the frame.

Time to get a coat of primer on all that unprotected new metal. I hung the frame up on it’s side so it would be easier to paint both surfaces of the floor pans. At the same time I hung up all the control arms to give them a coat of primer as well.

Time to fix those “miss installed” suspension brackets. I had extra brackets so I decided that the best plan was to cut the arms of the original brackets and put the brackets where they should be. Looks a bit ugly until you get a coat of primer on it !

I picked up a couple moving dollies because the frame is weighing about 185 lbs so it makes it easier to move.