How to make a Buck??

[David Gardiner]

Originally Posted by TheRodDoc

David,

That is about what it is. I figure one would only need half the car. Then duplicate the other half from that. Half of one lets you tip it up and pull it sidways away from the car after all the rods are set to touch the body. Then all you have to do is put your sheet of plywood up against the side of the rods and mark along all the points to draw out the shape. The frame of it would have a way to hold the sheet of plywood in the same place each time while drawing the shape on it.

Hi Richard,

My measuring bridge is exactly what you show ie. it profiles half the width of the car but instead of having a foot under the car the frame goes over the car and it has an identical upright in the other side thereby making a bridge. Mine is all steel but wood like you show would work just as well.

David

[Z5Roadster]

Hi Gents.

What a brilliant response, only joined a couple of days ago and now feel my project can move forward. Didn't think I'd get graphics as well, superb, what a master, thanks Richard. Somebody said something about 'a picture speaks a thousand words'

Why are the simple ways best.

The big plus to me is that Richards idea takes away any chance of transfer error and I did have a problem about taking into account metal thickness, that’s solved by the thickness of a pencil line.

Kerry, your comment on contour thru the buck thickness has been taken on board and think if I work on the top side of the profile, when I assemble the sections I can sand radii/angled form from one to the other to remove high spots.

The original bodies were mounted on a tubular framework and whether this should be incorporated I'm not sure, will have to give that some thought.

Stage 1 will be to fabricate a bridge, I do favour the half style for a kick-off.

Keep the comments coming, its good to know your there.

The sun is shinning

cheers

[52pickup]

Tom,

If you haven't already I recommend reading the Kirkham build book here: http://www.kirkhammotorsports.com/book_aoe/

A lot of it wont apply, but I may give you some ideas. Also, check out this thread: http://www.allmetalshaping.com/showt...t=cobra&page=1

Good Luck!

[Kerry Pinkerton]

Originally Posted by David Gardiner

...My measuring bridge is exactly what you show ie....

David, can you post some photos of your bridge?

Tom, there was a really great discussion on the Bugatti Build thread over on MetalMeet about buck design. Wray Schelin was going to design it using sheet metal which would nest like the wood but not have the thickness issues that wood does. On the wood, I understand that people either bevel the edges to a center, or work off the front side on the front side of the car (upslope) and back side on the back (downslope)

Unfortunately, the Bugatti thread was part of the 3 1/2 years of data loss in Larry's misguided upgrade attempt on MetalMeet.

[David Gardiner]

Kerry my measuring bridge is buried deep in my store, I have only used it a few time since making it, I made the buck for the Aston Martin DB2/4 convertible that is on my DVD. I will pull it out if I get the chance but it really is almost exactly like Richards drawing. The frame continues over the car and down the other side but it only takes a profile from one side as Richard describes the other leg is just for support so you don't need anything going under the car.

Rod Jolly used to have a photo of his on his site, he has now retired but the business is still going http://www.rodjolley.com/flash/workshop.html
I just looked it is still there, look under the workshop heading.

I worked at Rods for a very short period - I did not stay for a variety of reasons I regret it now at times.

Building a buck is a huge undertaking I would consider buying a glass body and working from that, you can reinforce it and cut clamping holes in it etc. It would not be dissimilar to the buck that the Kirkham's use. Building a wire buck from the glass body you can borrow would be another good option.

David

[TheRodDoc]

This is how I made the one I used to have.

Two strips of plywood with thick solid card stock inbetween were clamped together.

the wood was drilled in drill press the size of dowels using gage stop to space the holes exact. When done and unclamped throw out the cardboard and holes will now tighten down on the dowels when pinched together.

Then strap iron was cut and welded for each side.

After shape was welded together the two sides are clamped together and holes drilled for bolts. Then bolts are put in lathe to recut under side of head square and remove any radius in corner. This is done so bolts sit totally flat when put through the side plates. push all bolts through the two plates and use spacers on bolts so you can tighten all bolts some.

Now weld heads to one plate. This is to make the beam solid and not be able to flex sidways when finished. The only thing doing that will be the bolts.

take apart and put in wood. To lock all the rods or dowels, just tighten the nuts a little.

buckgage6.jpg

[Z5Roadster]

This is a must have, regardless of what type of Buck we finish up with, all my thoughts of lasers and data scanning are out the door.

Richard has a brilliant way of getting his ideas across, I've got the software, just don't know or can't use it.

From the little I have done this wk (working 12hr nights, last 1 tonight) It would appear that the bridge arm would need to be approx 80" long to be suitable for profiles from front to back, think that 80" would bring me from the nose to part way thru the cockpit.

Have got some 40x40x3 mm (1 1/2 x 1 1/2 x 1/8) M/S box kicking around and thought I would use that for the arm.

On how to locate and clamp the dowels.

What going on in my head at moment is to use 6mm (1/4) perforated sheet this would give the option to have different spacing for different profiles.

Firstly fold into a U section with an internal dims. of say 30mm (1 1/8) with an upright length of 13mm (1/2). This would only be half of the dowel location.

Would it be feasible to pass 2, 1/2dia air lines either side of the dowel which would give slight interference on the dowel and once all the dowels are set to the body profile plug in the airline with snapon fittings.
The airline could be 1 piece coming back on itself with a drain at the stop end.

Yes we would need a second hole to pass the dowel thru to keep it square but this only need be the same perforated sheet folded at 90deg.

The 2 pieces of perforated sheet could the be mounted on a 50 x 6 (2 x 1/4) flat of the same size of the arm and this in turn could be clamped to the arm using toggle clamps being that there would be a simple form of location on the arm.

Need a picture.

What I visualise is that with all the dowels set the air pressure will trap the dowels, we can then unplug the airline, release the toggle clamps and take the dowel profile to the plywood sheet (not sure if the snapon fitting would hold max pressure or if it may need a shut-off valve) time will tell.

All sounds a bit complicated but this will be part of the tool kit which I think will be used time and time again. Only want to make 1.

Cheers

[Z5Roadster]

Originally Posted by David Gardiner

Building a buck is a huge undertaking I would consider buying a glass body and working from that, you can reinforce it and cut clamping holes in it etc. It would not be dissimilar to the buck that the Kirkham's use. Building a wire buck from the glass body you can borrow would be another good option.

David

The only buck I have seen is just down the road, the guys that supply Shelby with chassis and bodies CSX4000 I think. Nice guys to talk to, will have to make a visit to them this next week. last time I went they had just relocated, stuff everywhere.

I do understand what you are saying David. More time spent thinking is less time doing. Like the gas welding approach, I have tig on the stick welder but never used it, will look to gas now.

Cheers

[Kerry Pinkerton]

Tom, there are lots of ways you can approach building the bridge and I'm sure that you'll get some real world input from the guys who have actually made one. I haven't.

What I did do however is use something like a bridge to fix a major problem on my roadster. I had build a buck for the left fender based upon the original right fender. I THOUGHT it was accurate and it may well have been. However, because of the multiple reverses in the fender, I could not keep it on the buck as I tacked it together. Long story short, the fenders didn't match and this became obvious at Oblong after the car had been driven and was sitting on a level slab where we could get far enough away to 'see' it.

What we did was make an accurate centerline mark on the floor by dropping plumb bobs from the center of the chassis. From there, we ran lines out 90 degrees and marked off increments. A free standing bridge was created that we could locate on the incremental marks on each side of the car and measure down and across to points on the 'good' fender to compare against the bad one.

Crude but effective.

[Z5Roadster]

Hi Kerry.

I like your input, I only wish I had the time to go thru all the various threads to increase my understanding of the different ways you guys do the same job.

Having worked in reverse all my working life I do have an advantage on the normal beginner.

Sounds what you are saying regarding the grid pattern on the floor, perhaps in theory 6" tiled floor would be a good asset.

What has also accrued to me is that I may need to mount an adjustable arm parallel to the floor to give the corner profiles. The ones shown in the Buck photo closes to you.

Good to know your there.