Board logo

Could someone check this FU/LA-D thread for me?
Mansfield - 28/8/06 at 08:44 AM

Bit of an old chestnut this one - front suspension locations.

http://locostbuilders.co.uk/viewthread.php?tid=50557

Robertst posted a thread recently showing his problems with FU and LA/LB relationships. I had been modelling this part of the chassis in CAD and I was having similar problems with suspension points.

A bit of searching on this site turned up this drawing from leto.

http://www.locostbuilders.co.uk/photos.php?action=showphoto&photo=front13-14.jpg

I think the drawing in the bottom right of the page provides the answer, and I have suggested to robertst that this could be the solution for him.

I have not started my chassis yet so all my thoughts are based on CAD and searches on this site. I would hate to give bad advice to robertst, he is having enough grief already. Is the advice sound?

Thanks, David


mark chandler - 28/8/06 at 12:27 PM

Simple rule, they need to be parallel to the centre line of the car. How you achieve this is up to you, pack out the front or extend the rear brackets.

For trick suspension you may try leaning them a couple of degrees from the hoizontal to add a bit of antidive.

Regards Mark


robertst - 29/8/06 at 10:08 AM

checking out the measurements, i am worried if i make the front too small, the car would look a bit dodgy.

i am worried i will need a book nosecone rather than the +4 nosecone i intended to use...

all the problem lies on having placed the top rails too far close to each other!
bugger.

thanks a lot for your help David. shows how CAD is a good tool to avoid cock-ups

quite like that rule Mark explained... gives you more than one solution..

cheers


Mansfield - 29/8/06 at 08:20 PM

I agree with you robertst, Mark's answer sums up the solution nicely.

I am glad to see you have found the cause of the problem, but very sorry to see that you have a such a problem.

At least now you can decide on a solution.

Best of luck mate.

David.


caber - 29/8/06 at 09:32 PM

All I can say is bollocks! I thought I had my front end sorted using the McSorely drawings but following this lot it looks like I will have to do something with my FU tubes, I only fully welded them in this weekend!
AARGH Caber


Mansfield - 29/8/06 at 10:10 PM

I have CAD modelled Mcsorely book and +442 fronts and I cant get either to work well.

Mark's advice seems like good advice to me.


robertst - 30/8/06 at 01:14 PM

moved LA and LB, looks pretty straight to me... any imperfections can be solved adjusting the brackets...
[img][/img]

which reminds me. i cant get the jig for the brackets right, let alone DO THE F*** HOLES WITH A DRILL! i get them all wrong and it jsut bothers me i cant keep to the 25mm hole distance thing...

whats more, the 50x50 RHS tube i'm using doesnt seem to fit on the wishbones, and i heard about filing them down until the wishbones fit... but i fing bending and filing 3mm thick metal pretty darn difficult...


robertst - 1/9/06 at 11:42 AM

just bought a new toy which i hope will ease up the task of doing the holes in the brackets:
a drill jig.

does anyone know how to measure/calculate/find out the hole positions for the brackets? because if i drill the holes at a constant measurement, the bracket jig wont line up with the chassis bones. and the differring lengths of the holes will account for errors in the FUs and Ls.