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fornt suspension bracket position
doughie - 6/1/07 at 04:31 PM

have searched the site (lots of informative stuff and pics)

am looking to site the brackets correctly (locost with tina front hubs)

the book says get a mate to hold the suspension arms and tack on...

but i think there may be more to it than that so looking to gather information and knowledge - what do i need to make sure of and are there any tricky bits to this??

i have cut and replaced sections of LA and LB and am going to cut FU1 and 2 out so its hopfully going to be from scratch...

in advance, all help appreciated; thanks for reading...


big_wasa - 6/1/07 at 04:41 PM

Make a Jig to hold all four brakets at the correct spacings. Make sure it is parallel to the center line of the chassis. Tac them to the chassis.

This imho is the best way to find the position for F1, F2.

regards


big_wasa - 6/1/07 at 04:42 PM

pic 2


doughie - 6/1/07 at 04:53 PM

cheers big-wasa, thats just what i was looking for
what measurements are needed to make sure all the brackets are in the right place? (using gts bones - beleive their not adjusted to get correct camber????)


big_wasa - 6/1/07 at 05:07 PM

You will not get the 6 deg of castor as in my pic because the brackets will end up over hanging the chassis by an unsafe margin.

Make sure the brackets are spaced so that you will get your bones in them. Then try and get the top mounts as far back as you can whilst having proper surport on the chassis.

Best you will get is the top bone being 10-15mm behind the center of the bottom bone.
Some people make two jigs and then cross brace them so that you set all four brackets in one go and perfectly parallel to the center line of the chassis.


big_wasa - 6/1/07 at 05:09 PM

Not mine. Found on here


Peteff - 6/1/07 at 05:10 PM

Watch where you put the fu tubes so you can still get a nut on the bottom rear bracket or put the bolt in from the front and have to cut it to get it out (as if anybody would do that) . It was a long time ago and there were no forums (that's my excuse anyway)


big_wasa - 6/1/07 at 05:30 PM

pic3


doughie - 6/1/07 at 05:57 PM

cheers, will do a mock up and see what happens - will try to get some pics on here to show you

p.s. thats some tidy welding you got there BW


StevenB - 7/1/07 at 02:01 AM

B_w,

any chance you can describe roughly where in the vertical plane
the shock mounts will fall relative to the top and bottom red dots?

ie for the top...centred on the top red dot on the under side
of the top chassis tube etc

cheers
s


Mark Allanson - 7/1/07 at 07:43 PM

I did mine in a very similar manner, I made the brackets symetrical and redesigned the upper wishbones to give the castor, the brackets sit nicely on the chassis, and I have more than enough self centring Rescued attachment Wishbone Jig.gif
Rescued attachment Wishbone Jig.gif


Bob C - 7/1/07 at 08:04 PM

I think my system's better than any of these..... :^)
Bob Rescued attachment frsusjig.jpg
Rescued attachment frsusjig.jpg


Mark Allanson - 7/1/07 at 08:18 PM

Bob, excellent longditudinal location, but how does your jig set the distances between the upper and lower brackets? and the exact mirror on the other side of the car?


Bob C - 7/1/07 at 08:41 PM

Yo mark - maybe it's not so clear on the photo - there are peices of tube cut to appropriate lengths (including a 10mm piece I could move in front or behind to optionally give me extra caster ....) 12mm rod with a threaded end holds everything in place & runs through the tubes. The plates are marked out clamped & drilled together. There's an extra small "gunsight" hole bottom middle to make sure it all lines up with the car centre line.
And I have the jig in my shed if anyone wants to come & borrow it....
Bob


Bob C - 7/1/07 at 08:47 PM

Just re-read you post mark - that's set by the positions of the 12mm holes on the plates - it just needs careful marking & reasonable tolerances.
Note I used this jig to position not just the brackets but also the FU tubes and the upright Lx too
Bob


doughie - 7/1/07 at 09:02 PM

cheers, wish i was using mx5 uprights!!

Mark, like the animated photos


Mark Allanson - 7/1/07 at 09:50 PM

Still got the jig rusting away in my garage!


Nisseven - 9/1/07 at 09:29 AM

A version of Marks jig is exactly how I planned to do it, as it locates everything exactly to a centre line where it should be.
This is not meant to be a critisism of Mark but I noticed in the photo that the chassis was still only tacked to gether. Do you think that you should fully weld the chassis first so that any distortion can be dealt with by the final positioning of the suspension brackets?
Bruce


Bob C - 9/1/07 at 01:28 PM

it's chicken & egg Bruce - if you weld up the chassis you will find it's in the wrong place to get the wishbone pivots right.
I had to move all 4 uprights.
My chassis didn't move a lot after it was tacked
Bob


Nisseven - 10/1/07 at 09:55 AM

Hi Bob,
Yes I understandwhat you say regarding the position of the chassis members the brackets are mounted to and this is a problem because of the "U" shaped brackets used. For this reason I am making brackets which are essentially flat plates welded to the sides of the chassis members, which gives me the advantage of positioning them very accurately. I think that they will look good to. I am close to that stage now and will post some photos when I have done them to see what you think.
Bruce


Nisseven - 10/1/07 at 10:09 AM

Sorry Bob, In an earlier post I was refering to Marks jig when it was yours that I thought the best. As I said I intend to make one the same except that it will not be able to be two flat sheets like that as I have diagonal bracing in the way, but the principal will be the same.
Bruce


James - 11/1/07 at 04:25 PM

Pics of how I did mine:
http://www.locostbuilders.co.uk/photos.php?action=gal&user=James&folder=Bracket%20Jig

Hope it's of some use.

Cheers,
James