I will be designing/building the engine mounts for my car in the next couple of weeks and was wondering what thickness metail to use.

The design will be very basic as I am mountng the engine on Escort World Cup Cross memeber bobbins. So the basic design is -

Square section tube with the chassis end cut out and drilled to fit the bobbin (65mm across), the other end cut off at an angle to be welded onto a flat plate that will be bolted to the engine.

The Square section will be 70mm Outside square mild steel tube with either 2mm (plus shims) or 3mm (ground off a bit) thichness but what plate thickness do I need for the engine plate - 3mm/4mm/5mm/6mm ?

Any ideas/thought gratefully recieved.

I used 5mm thick plates, and 33x3mm tube:
http://locostbuilders.co.uk/viewthread.php?tid=171955

Depends on the length of the engine mount, the space between the member and the bolt holes, weight of the engine and the likely leverages that the plate will see.

I have never used anything greater than 3mm but will web and strengthen accordingly depending upon the factors above.

Andrew

Out of interest are Escort World Cup Cross member bobbins the same as ford transit engine mounts? Would you mind measuring them for me?

5mm plate and 25mm SST for mine.
HTH.
Cheers, Pewe10

Thanks for the help guys, much appreciated.

Ceebmoj, not 100% sure but I think the bobbins are 65mm wide (across bolt tube ends) not sure about diameter, will check tonight when I get home. That was the reason for the 70mm with 2/3mm thich walls for the main member.

As for weight etc, the engine is a 1.7 Puma so with the gearbox will be around 140kg, the engine brackets will be quite long with 6/8 fixings near the front of each but the cross memeber bobbins are fairly far back on the engine.

Not sure if this shows it well. Bobbin can just be seen just below the piece of blue wood that the engine is resting on, mounting holes for the plate are near the front of the engine (AC pump bracket holes)



EDIT - after a bit more searching

That said, although the WC bobbin mount is very neat I had a read through the Epic Zetec SE Escort thread - http://www.turbosport.co.uk/showthread.php?t=145051&page=4 - an he mounted directly onto the rails which would be a much easier and possibly simpler solution. I could then grind off the WC mopunts and save my self the problem of remote mounting the oil filer.

[Edited on 19/8/14 by Ugg10]