Prelude3.com/Chassis

Here the Prelude is in position for the draw bench. On the driver's side in front, the chassis was pushed both inward and downward by the collision. A big clamp is bolted onto the front cross member. Through this clamp's eye, a big metal chain will be attached to the draw bench.

The chain is pulled tight through hydraulics, taking the cross member with it. By hitting it with a big hammer, the cross member is returned to its normal shape. Cross measuring is done frequently to determine the amount of pulling still needed to return the cross member to its original position. It's a very precise job.

To be able to see if the chassis was successfully straightened, the engine hood, front fenders and headlights were installed. Everything fitted nicely and the seams matched up everywhere.

Afterwards the spot-welds were ground down, treated with zinc coating and finally primered. All parts originally covered by it now got a new layer of kit. In the top right corner of the photo there's the sandblasting machine I used for treating the rust on the side sill.

After the side sill was thoroughly sandblasted on the inside, and I knew all rust had been blasted away, it was zinc coated as well. I had a spare sill I bought a while ago at the Van Deijne scrap yard, which was in perfect shape without any rust. The needed part was cut off and welded to the existing sill. After the welding it was covered with zinc coating again, as can be seen on the picture.

The engine bay was already empty except for the steering rack. Now that the front bulkhead was back in, the engine bay could be mildly sanded for good adherence with the primer. Because the surfaces in the engine bay are far from flat, it would be nearly impossible - and impractical - to try and reach everything with sanding paper. That's why I use "Scotch Brite".

After scotching the engine bay I zinc coated the places where the paint had been sanded off. On the picture beside there's the left front which used to be damaged. The donor front bulkhead was welded to this part, and to finish it and prevent any possible rusting, the seams were sealed off with black, flexible kit.

The underbody of the car has to be in perfect shape as well, so I've inspected it thoroughly. After removal of the fuel tank I was surprised to see this spot wasn't protected by underbody coating, which was probably the reason some rust formed here. As you can see I've begun removing the rust here. I use a Dremel tool with little grinding discs, because you can reach all the areas with it.

When all the rust is gone, a zinc coating can be applied. Over the areas more sensitive to corrosion, I applied kit. As soon as the car is repainted, the whole underbody will receive a new coating. This has to happen after the paintjob, because the coating has silicone components in it. Repulsion occurs between these components and the paint, which will get some bizarre shapes in your paint.

*Chassis*
I think one of the most important parts of my car is the body, which is the most visual part of any car. It's the exterior and what people get to see first. Because the third generation Prelude wasn't zinc plated yet, rusting is a common problem for these lovely cars. Especially untreated cars suffer from rust on weak spots like the rear wheel wells and arches, on and around the sunroof, around the rear window and on the rear of the side sills. For my project I wanted a good base to start from, which meant I had to find a car without rust and damage. The fact that these cars are getting old made this an almost impossible task. To get a car as close to perfect as possible was my goal. In the end I found a 1989 EX without visible damage or rust. Of course it's always a gamble; you can hardly strip down the whole car in front of the seller.
As I took off the front bumper of the Prelude EX, I noticed minor front damage. After taking off the headlight assembly it became clear the chassis on the driver's side was somewhat bent inwards. The front bulkhead was quite damaged too, as you can see.
	The front bulkhead was too damaged to recover. On the areas where the paint had cracked, rust was already visible. So I threw it away. First I drilled out all spot-welds so that it could be removed easily. Beside you see the bulkhead completely taken off.
Luckily I didn't bring the chassis of my old 16-valve Prelude to the scrap yard yet. The front bulkhead of this chassis was in good condition. Again I drilled out all the welds and the bulkhead was recovered undamaged.
	After a very thorough inspection of the whole body, I discovered some superficial rust on the right side sill right in front of the rear wheel. Not taking any risks, I cut out a 10x15 cm piece so that the corroded metal was clearly visible and thus easier to treat.
Ready for the journey to the body shop. An acquaintance who's a body worker would skillfully repair the chassis, and return the car about a week later.
	Here the Prelude is in position for the draw bench. On the driver's side in front, the chassis was pushed both inward and downward by the collision. A big clamp is bolted onto the front cross member. Through this clamp's eye, a big metal chain will be attached to the draw bench.
The chain is pulled tight through hydraulics, taking the cross member with it. By hitting it with a big hammer, the cross member is returned to its normal shape. Cross measuring is done frequently to determine the amount of pulling still needed to return the cross member to its original position. It's a very precise job.
	After cross measuring the chassis on top and bottom, we concluded the front had moved sideward as well. It appeared the collision to the front had been harder than we thought. To correct this, the draw bench was moved into another position, so that the front could be pulled sideward. The new front bulkhead is held in place using clamps here.
To be able to see if the chassis was successfully straightened, the engine hood, front fenders and headlights were installed. Everything fitted nicely and the seams matched up everywhere.
	Now that we were sure everything's in the right place, it was time to weld the front bulkhead to the chassis. This was a job I really couldn't do myself, because I don't have any welding experience.
Afterwards the spot-welds were ground down, treated with zinc coating and finally primered. All parts originally covered by it now got a new layer of kit. In the top right corner of the photo there's the sandblasting machine I used for treating the rust on the side sill.
	Over a week later I could retrieve the Prelude. Everything was repaired quite professionally. Unfortunately I was unable to take pictures of the welding of the rear panel and the side sill, but trust me, it was done very nicely.
After the side sill was thoroughly sandblasted on the inside, and I knew all rust had been blasted away, it was zinc coated as well. I had a spare sill I bought a while ago at the Van Deijne scrap yard, which was in perfect shape without any rust. The needed part was cut off and welded to the existing sill. After the welding it was covered with zinc coating again, as can be seen on the picture.
	The weather was good and the sun shining brightly. The perfect weather to work outside for a change, so I took the opportunity to clean the wheel wells of the Prelude and get rid of all the sand and mud. Also I marked every ding and dent on the body with a black marker; this will come in handy later working on the body.
The engine bay was already empty except for the steering rack. Now that the front bulkhead was back in, the engine bay could be mildly sanded for good adherence with the primer. Because the surfaces in the engine bay are far from flat, it would be nearly impossible - and impractical - to try and reach everything with sanding paper. That's why I use "Scotch Brite".
	Scotch Brite is a sort of rough pad available from several brands. I use 3M for its quality and durability. Several sorts of Scotch are available, each with its own color and roughness. For the inner parts of the car, like the engine bay and trunk, I use the red Scotch. It's quite rough making it unadvisable for the exterior. I use grey Scotch pads for that.
After scotching the engine bay I zinc coated the places where the paint had been sanded off. On the picture beside there's the left front which used to be damaged. The donor front bulkhead was welded to this part, and to finish it and prevent any possible rusting, the seams were sealed off with black, flexible kit.
	The state of the Prelude with all parts disassembled. I ground away every little rust stain with a Dremel tool, then covered all bare metal with a zinc coating to keep the rust from returning. The underbody wasn't rusted and was undamaged. Actually, the body is nearly ready for painting, but I'll wait a little longer for my body kit to arrive. And I'm going to try and repair the little dents myself.
The underbody of the car has to be in perfect shape as well, so I've inspected it thoroughly. After removal of the fuel tank I was surprised to see this spot wasn't protected by underbody coating, which was probably the reason some rust formed here. As you can see I've begun removing the rust here. I use a Dremel tool with little grinding discs, because you can reach all the areas with it.
	When all the rust is gone, a zinc coating can be applied. Over the areas more sensitive to corrosion, I applied kit. As soon as the car is repainted, the whole underbody will receive a new coating. This has to happen after the paintjob, because the coating has silicone components in it. Repulsion occurs between these components and the paint, which will get some bizarre shapes in your paint.

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