Thread: Followed Me Home II

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Roger, I've never worked on a fiberglass car, but on boats they use wood stringers for structural support that are resigned and glassed in that give quite a bit more strength to the vessel. Not sure if you can glass over steel, but you could definately get more stiffness and protection with some hard wood glassed onto the inside of the rear where nobody would see it.

Very Nice, it's coming to gether.

Originally Posted by rspears

So the PO painted the chassis black, but the differential, ladder bars, brake pedal and extension bar were all painted an "interesting" greenish gray.



He "remembered" that it was an epoxy primer with Eastwood's Aluma Blast, which is an acrylic lacquer which would mean it has to come off before re-spraying. However, the finish would not soften with lacquer thinner or reducer, so I'm going to rough everything with a red scotch brite pad, clean it good and give it a seal coat of good epoxy primer followed by black base & clear.

With the body on the frame I realized that the back end was not seated and noticed that it was sitting on the brake line fittings. A quick look at my '33 confirmed the need for a relief cut which I should have known was necessary, but was done on my roller package from N&N.



With the body back on the frame and down tight I hogged out the holes a bit and got everything bolted down. In that process I noted that the metal internal bracing, which fits at several of the body mount holes, is not bonded to the body anywhere. This structure is at the cowl, and there is a piece of sheet metal welded to the top rear that sort of forms to the top of the cowl but it has a gap of at least 1/4". Seems to me that for the steel to function as an overall stiffener it needs to be bonded to the body. I can use body filler, but there may be a better way?



I had looked at the bracing in the back earlier, but the more I thought about it the less I liked the way it was done. The 1x1 tubing structure braces the door latches, and extends back to wrap across the interior seating area which is fine. What concerned me is the extension that angles back on both sides, anchoring at the rearmost body bolt and extending with a loop across the back just below the trunk opening.





My concern is that any significant impact from the rear is going to push through that bracing into the structure immediately behind the seats, an potentially deforming that structure into the driver/passenger. Since I've been hit twice from the rear, the more I looked at it the less I liked it so it now sits on the shop floor.



This is the revised view from the trunk opening, which is very nearly like my '33 in function.



Monday I'll stop by the metal shop and pick up a couple of pieces of 1/8" strap, nominal 1.5" x 30" and form them to fit the arch of the floor between the two rear body mounts.



Once bolted in place I'll weld it to the tab of the remaining bracing which shows on the left, tying them all together. Any lifting force will have to rip out the entire trunk floor area as opposed to pulling out a small plug around a mounting bolt.

I've got a bit of welding to do, then will be pulling the body again and getting everything out of the way to paint the loose parts of the driveline, and to hit the outside rail of the frame with two or three coats of clear. Once that's done I'll get started mounting the front & rear suspension, and get this chassis on the ground.

Roger one reason the steel is not bonded to the fiberglass is that the glass and steel move around different in the heat and you would be able to see that in the sun after it was painted... My '33 roadster was from Westcott and it had a steel cage in it and that was the reason they gave me for not bonding the steel to the glass... even the coupe from N&N the steel is not bonded in places you could see after it's done..

Originally Posted by parkwood

Roger one reason the steel is not bonded to the fiberglass is that the glass and steel move around different in the heat and you would be able to see that in the sun after it was painted... My '33 roadster was from Westcott and it had a steel cage in it and that was the reason they gave me for not bonding the steel to the glass... even the coupe from N&N the steel is not bonded in places you could see after it's done..

I'd thought about that, wondering if the bonded spots might be a "tell" in the heat. On my coupe the steel in the body and door that mounted the hinges ran full height against the fiberglass, and the same for the striker side. This one has a piece of steel "floating" on the front door edge of the body, simply bolted to the fiberglass and not tied into the steel structure of the cowl. I suppose that the body is pretty stiff in that area, but it strikes me odd. On the jamb side the steel in the body surround runs up from the body to frame bolt, and has a little box kickout about 3" high and 2" wide to close the gap to the door jamb, and the only thing tying them together is the striker bolt. Again, just strikes me odd that the support was not shifted forward and tied to the body in a few places. I guess it's OK, but I'm feeling a little "iffy" with it at the moment. I suppose the steel is just there to hang things from, like the steering column up front, and not so much to stiffen the body.

YES, do not bond the steel to the fiberglass. Would make a real mess of outside surface of your car after it heats in the summer and cools in the winter and goes through lots of heat/cool cycles daily during its lifetime. You are right, just there to hang things from and stiffen the door hinges and latches, to to stiffen body

As Gary said Rog, DON'T bond it. Nothing wrong with bolting the 2 together
Steel and fiberglass expand and contract @ a differant rate, causing lot's of problems.
That's the way Cheeeeeepie bodies are made, and most of those are done with a chopper.

OK, I've got the No Bonding point. I'm not sure if it's that this body sat on a flat dolly for five years, or if it's just a normal thing but the doors are about 1/4" wider at the top than the bottom and the passenger side has to be forced closed at this point. I was attributing it to not being anchored well enough but I guess that's not the case. I'm going to look at it closer tomorrow, but thinking that I need to shim the body mount at the back of the cowl up a bit,the one just at the back of the door, or both.

Originally Posted by rspears

OK, I've got the No Bonding point. I'm not sure if it's that this body sat on a flat dolly for five years, or if it's just a normal thing but the doors are about 1/4" wider at the top than the bottom and the passenger side has to be forced closed at this point. I was attributing it to not being anchored well enough but I guess that's not the case. I'm going to look at it closer tomorrow, but thinking that I need to shim the body mount at the back of the cowl up a bit,the one just at the back of the door, or both.

Roger take a look at the Wescott web site they have a good tech part about how to shim the body.... www.wescottsauto.com

Thanks for the Wescott link! That's a very well written guide.

Originally Posted by rspears

Thanks for the Wescott link! That's a very well written guide.

Yes i pretty much wore the pages out on that plan when i was shimming my roadster body for the first time... never having done one before it was sure a lesson by fire..

Good source, Wescott's have been at it a long time and sure do build some quality units!!

Hummmmmmmmm---post # 22??????????????


However---I don't agree with the article about supporting the frame at the front and back----it needs to be supported by the suspension or possibly at the wheel c/l areas so it has the natural flex to the frame--support at the ends causes a dip to the middle which distorts the roadster (topless) bodies severly in the door opening/door fitment area-----------an issue that doesn't show up as bad with a coupe/sedan-----

Originally Posted by jerry clayton

Hummmmmmmmm---post # 22??????????????


However---I don't agree with the article about supporting the frame at the front and back----it needs to be supported by the suspension or possibly at the wheel c/l areas so it has the natural flex to the frame--support at the ends causes a dip to the middle which distorts the roadster (topless) bodies severly in the door opening/door fitment area-----------an issue that doesn't show up as bad with a coupe/sedan-----

Not to argue the point Jerry, but if you look at the cross section of the fully boxed '32/33/34 frame it's hard for me to imagine that there is much flex influence by shifting the rear support points back two feet to the rear spreader bar. The only force involved is gravity on the mass of the frame, and the article deals with measuring the static level points across the rails. I can't see that placement of the support points really matters as long as they are consistent and not staggered.

Its your car Roger-------------


However you are dealing with a frame with a c notch cut over the rear axle and using a poorly braced open top body----if you would place a cross pole in/at that c notch, you would eliminate most of the flex------------maybe some of the other body work guys will chime in--------








and Roger this isn't just nitpicking your work but trying to contribute some usful info to a thread that might be helpful to some others--------

To be clear, we're talking about a bare frame sitting on three jack stands with no weight considered other than the mass of the frame itself, as shown in the Wescott Instructions, and you're opinion is that the frame is going to flex at C notch because the supports are on the back spreader bar? I think you'd better go back and review basic statics. If the C notch allows flex under that loading it would be sagging when you fill the gas tank!!