Fender Braces for Information

Struts, spring, anti-rollbars, braces and the like.

Moderators: Helpinators, Moderators

Post Reply
Larry Witherspoon
First Gear
Posts: 91
Joined: Fri Oct 18, 2002 4:08 am
Location: Torrance (Los Angeles), California

Fender Braces for Information

Post by Larry Witherspoon »

I am very close to having a few fender braces, and I don't have a price - Rite now I am willing to trade material for knowledge

They look like these Simply Subie braces in the Parts Shed Vendor Garage, but without the three big holes - viewtopic.php?f=23&t=34447

Simply Subie was no longer making braces when I went looking, and wanted more for the CAD/CAM file than I was willing to pay

So I got hold of a stock fender brace, to make an engineering blueprint by taking careful measurements

However the stock brace hole diameters are 12 and 14 millimeters, two mm and four mm LARGER than the 10 mm, M10-1.25 threaded bolt holes in the chassis

I don't know if that's because the chassis manufacturing tolerance was so wide the braces needed room for variation

And I didn't feel like I could depend on the stock brace and chassis holes to be concentric

So I managed to get an actual chassis section with the brace attached so I could measure the chassis hole pattern directly, and made what I believe to be an accurate engineering representation

At a glance it appears the hole centers form a parallelogram, but they do not...none of the lines connecting hole centers are parallel !

I took my drawing to a metal fabricator, who converted it to a CAD/CAM file, and I was able to have braces CM machined, duplicating the chassis hole pattern to +/- 0.015 in (0.38 mm)

The braces have not been tested for fit on a car, and you probably know about Murphy's Law

But I don't know if the chassis section I had is held to a close tolerance so as to trust that ALL are the same

And even if they WERE identical off the assembly line, after cowboys have been jumping, crunching, rolling and Evil Kineveling their car all over the place, where is that chassis alignment now ??

Even on the section I used to make the drawing, there is a slight fit problem. I can get all the bolts thru the brace and started by hand into the chassis threads, but cannot tighten them all the way with my fingers.

I got some long bolts so I could try to determine whether the holes were axially parallel and guess what, it turns out they are not quite. The frame section is slightly out of kilter.

I can slip the long bolts all the way through the brace holes, and tighten the bolts into the chassis with the brace up at the top of the bolts, then slide the brace down to the frame section, and see how it slightly deforms

The machined brace holes are very nearly concentric with the chassis/frame section holes, but we can't do much about the out of parallel condition, and I think it helps explain the oversize holes in the stock brace

Fortunately, the imperfect alignment and fit is not so severe that it would cause problems using something better to tighten than fingers

And perhaps that slight misalignment preload would actually assist in resisting movement between the two parts of the chassis these braces are intended to tie together

So I am wanting to find out if my existing brace holes that just barely allow the bolts to slip thru, are adequate in the real world, to fit the braces to the chassis, or if not, how much oversize they need to be

I would like to find somebody who is willing, and able to remove their fenders, and stock braces, and try the ones I had fabricated, in trade for free braces

They are 6061-T651 Aluminum plate 1/4" x 3-5/16" x 16-7/16", laser cut and drilled to my blueprint

I think the best use of mine would be to fit them UNDER the stock braces, so BOTH are used to stiffen the chassis, if there is room.

I am not actually starting a manufacturing and supply business, there was a minimum order quantity, and I have a few paperweights I don't want to go to waste, that might be worth a few dollars to the community if they work well.

Simply Subie indicated the below fitment info

FIT
ALL 90-94 Legacy Sedans and Wagons
ALL 02-07 WRX Sedans and Wagons
ALL 99+ RS Models
ALL 04-07 STi Models
SOME 93-01 Impreza L models will require two holes to be drilled and tapped.

Please reach out and touch me

Larry Witherspoon

p.s. - I also want to buy a few items for my 92 Legacy listed at the bottom of this same post in the Parts Shed
Larry Witherspoon
ssspoon@aol.com
Torrance (Los Angeles)
92 Turbo Legacy Wagon
310-429-4269
arse_sidewards
In Neutral
Posts: 31
Joined: Thu Jul 21, 2016 12:17 pm

Re: Fender Braces for Information

Post by arse_sidewards »

So what are you asking for here? Someone to measure another vehicle so you can be sure your dimensions are right? I have a car sitting without a fender in my driveway.

If you're not concerned about selling these and protecting IP post up a dimensional drawing so we can all use them.
'93, '93 and '94 Legacy L, wagons, FWD and AWD, all are NA 2.2 w/ 4EAT.
Legacy777
Site Admin
Site Admin
Posts: 27748
Joined: Tue Oct 15, 2002 11:37 am
Location: Houston, Tx
Contact:

Re: Fender Braces for Information

Post by Legacy777 »

Hi Larry,

I ended up getting the TiC fender braces a while back. I had to drill out one of the holes slightly to get things to line up so I think you're going to have a little bit of tweaking on every car unless you want to enlarge the openings as you have seen in the stock brace.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
Larry Witherspoon
First Gear
Posts: 91
Joined: Fri Oct 18, 2002 4:08 am
Location: Torrance (Los Angeles), California

Re: Fender Braces for Information

Post by Larry Witherspoon »

Hi Josh, Hello Mr. Sidewards

Guys, PLEEZE forgive my late response to your posts

For some reason, either i missed the automatic email that my subject had a reply, or somehow it didn't make it thru cyberspace to my desktop

Josh you wrote.... I think you're going to have a little bit of tweaking on every car unless you want to enlarge the openings

Yes that's exactly what I want to determine.

I don't want to enlarge openings, but if that's the reality of the manufacturing process, my fancy close tolerance holes shot me in the foot

And what is the little red dot, next to my original post please ???


Mr. Sidewards, that sounds GREAT !

If your frame will accept my braces as is, I would be a lot more confident they will work without tweaking

How do I get them to you ?

I don't have a dimensioned digital drawing

I created a full size pen and ink hard copy drawing on 11x18 sheet that was translated into a CAD/CAM file the fabricator provided to me on a thumb drive, which just looks like a rotatable 3D wire frame image when opened

I hesitate to put something out there that causes peeps to spend time and money on, then have it not work

To what name and address would you like me to send the "prototypes" please ?
Larry Witherspoon
ssspoon@aol.com
Torrance (Los Angeles)
92 Turbo Legacy Wagon
310-429-4269
arse_sidewards
In Neutral
Posts: 31
Joined: Thu Jul 21, 2016 12:17 pm

Re: Fender Braces for Information

Post by arse_sidewards »

I don't need you to send me the brace. Providing the drawing or CAD file would suffice.

I have access to a CNC router so I can just slap a piece of stock on there, pilot drill it and then test fit on my vehicles. Or I could just print out a fullsize template and use a punch.

I crashed a car last week so now I have two cars sitting in my yard without bodywork installed to test fit on.

What format is the CAD file you have? Since it's a single part it shouldn't be hard to work backward from a wire frame to a solid and slap it in a normal CAD format (sldpart or something).
'93, '93 and '94 Legacy L, wagons, FWD and AWD, all are NA 2.2 w/ 4EAT.
Larry Witherspoon
First Gear
Posts: 91
Joined: Fri Oct 18, 2002 4:08 am
Location: Torrance (Los Angeles), California

Re: Fender Braces for Information

Post by Larry Witherspoon »

That CNC router sounds very cool -

I don't know about CAD formats, the shop that did the machining just put it on a thumb drive

However I do remember a goof with the CAD file

I had originally intended to tap the holes to match the body, then found out after the job was done that tapping the holes was not a good idea

For a bolt clamped assembly, it is better to have only one component tapped, or unless by some fancy luck, the threads in the second piece will likely NOT be picked up by the entering bolt thread exactly right, and the threads will actually prevent the strong clamping action desired

And so the holes in the CAD file are too small, and I had to go have the parts drilled out more to properly accommodate the bolts

But even after they were enlarged, the fit is pretty tight, so like Josh said, they may STILL not line up and need MORE enlarging to fit any car

And the reason I want to send you the hardware is because I would like to find out if they will fit another car (or cars), and if not, what needs to be done further so I can perhaps fix the dozen or so sets I had to buy for a minimum order quantity

Now you know the whole story of me trying to escape getting caught by Murphy's Law

Thank you for the info and offer

Meanwhile I am looking for a few first generation Legacy parts - Are the cars you have sitting there available ?
Larry Witherspoon
ssspoon@aol.com
Torrance (Los Angeles)
92 Turbo Legacy Wagon
310-429-4269
Legacy777
Site Admin
Site Admin
Posts: 27748
Joined: Tue Oct 15, 2002 11:37 am
Location: Houston, Tx
Contact:

Re: Fender Braces for Information

Post by Legacy777 »

Larry Witherspoon wrote: Fri Apr 30, 2021 3:15 am Hi Josh, Hello Mr. Sidewards


I don't want to enlarge openings, but if that's the reality of the manufacturing process, my fancy close tolerance holes shot me in the foot

And what is the little red dot, next to my original post please ???
Hi Larry,

I'm not sure the red dot you're talking about. It may just be indicating there are new posts in your thread.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
Larry Witherspoon
First Gear
Posts: 91
Joined: Fri Oct 18, 2002 4:08 am
Location: Torrance (Los Angeles), California

Re: Fender Braces for Information - little red dot

Post by Larry Witherspoon »

OK - eyes going bad
it's a little red STAR just to the left of the subject line
Thanx for the explain
Larry Witherspoon
ssspoon@aol.com
Torrance (Los Angeles)
92 Turbo Legacy Wagon
310-429-4269
Post Reply