In preparation for making the buck under-structure I created outlines both longitudinally and transversely across the 3D mesh.
I have rendered each outline individually in the front plane and have included in the rendering an object of known position and dimension in the scene for measurement verification and positioning. These outlines will be projected onto craft paper taped to a wall using a DLP projector and traced out. More accurate and less time consuming would be a plotter, but that's also way more expensive since I would have to use a reprographics bureau.

I won't use all the outlines displayed below for building the buck, but it's nice to be able to choose the best ones to cut out of plywood.

The goal is to construct a fairly accurate base upon which to span between with foam insulation paneling and then use drywall plaster and Kilz. Just like Alan has done.

Anyone care to comment on my process? I haven't started tracing or cutting, so now is the time to accept knowledgeable advice.

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Very nice drawing Mr. Graber.
Wish i could start to think about "bodywork" yet.
I would use more horizontal verification lines lenghtwise,at least one between the top and bottom lines, because they are harder to compare (far and nearside of the car) than the shorter vertical shapes,on the other hand....i even havnt built a model car in my live so...

Sounds like an excellent process.

Then, I guess, I would say that wouldn't I?..

Seriously though, the only thing I would have changed on mine would have been to have more station templates.....an issue which you have addressed, so IMO you should be fine. Another major advantage is the filler should dry REALLY quickly in AZ...

Yep, loooking good mate..

Just a thought...

If you project directly onto poly sheets marked with 1' gridlines, you'd be assured of fidelity to scale AND you could do your 'tracing' with a razor blade knife

Pete

quote:

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Originally posted by pbura
Just a thought...

If you project directly onto poly sheets marked with 1' gridlines, you'd be assured of fidelity to scale AND you could do your 'tracing' with a razor blade knife

Pete

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You gotta change the title of this thread a bit, I got you confused with alan, thinking he chopped his body up, which Ive actually grown quite fond of. I Have no comment for you other than good luck, and try to take less time than Alan is because I'm pretty impatient, and really hate weaiting for the finished results.

Hey, whaddaya know! One of my goofy ideas stuck!

OK, then, here are some more :

--Instead of building the buck on the car frame (don't know if this is your intention or not), how about building a plywood frame, with a large flat horizontal sheet about 1-1/2' off the ground, and vertical sheets along the centers of the sides, and also front and back. These could be 1/4" thick and framed with 2X2s. Then you could notch your poly pieces and hang them on, fixing them with duct tape and maintaining spacing with dowels or plastic tubes glued in the spaces.

--How about using that crazy expanding foam you can buy in 5 gallon buckets to provide most of the bulk? Then use drywall compound for the top inch or so. Drywall compound is a great idea (Alan's?) for filler, so nice to work with compared to body filler, and cheap.

--Maybe body filler could be used for some of the fine details as it is sturdier and doesn't shrink so much. For some features, you could make your own edge and radius knives out of sheet metal. For long edges, maybe you could try gluing on plastic drywall corners. Betcha that even the "knife" edges could be formed with a 1/16" radius.

Your final finish will probably be a product of patient art, like Alan's, filling and sanding repeatedly and squinting at it from all angles. An old bodyman's trick is using contrasting shades of finish filler coats so that the high and low spots jump out at you.

Way to go, Steve! I think you're going to have a lot of fun with the dreaded Bodywork Phase

Pete

All valid points Pete. However I am stuck with 1/2 of a 2 car garage and 3 cars... So the body will have to be built over the frame due to space constraints. What I intend on doing is affixing plywood backbones to the frame with some u-clamps and attaching the foam panels to that with whatever method holds best. Nails, planks, hot-glue....

The idea for the drywall corner bead is a good one. I will have to see what is available.

Time to go to Home Depot for some reconnaisance...

Derf-man, I'll try to satisfy your impatient nature. LOL I should be able to finish a lot faster than Alan because the filler will indeed dry about 10x faster here than in Florida.

Graber

And it's even drying pretty fast here at the moment...

Although it's only some minor repairs right now...

When's your next update Alan? I wanna see some good stuff.

Graber

Hey Syd,

I'm not upset or bothered in the slightest. (I'm sure you knew that..)

I KNOW that your methods are well proven and established. I'm simply pursuing my own low cost (certainly in terms of materials, if not labour) methods and trying to develop them to reasonable degree.

The last thing I'm saying to anyone is "copy me, this is the best way" but rather "hey guys, this works for me and it's very cheap"

But, again, I'm sure you know this Syd..

One day I will buy some Duratec and give it try...promise...

Thanks Syd, All very good advice. I am wondering though, why not skip the fiberglass base and go straight for the skip coat over the foam? It may end up being fragile like an eggshell, but the only thing that will be touching it before it is will be the multiple layers of fiberglass that will form the actual mold part.... Then it gets discarded anyways... Just curious. And always looking for ways to save money.

Also, Any reason you can think of not to use 1"rigid styrofoam in lieu of the MDF/Plywood for the ribs? I think it will be cheaper to buy (Need to get to the store to find out tho.) Inserting foam blocking in between will stiffen it up significantly.

Graber

If you skip the fibreglass when using foam you will be pretty much be guaranteed only one shot at the mould. You will destroy the plug getting the mould off for sure. Also you need to be careful when building up the mould as the heat generated by the curing process could deform the foam. Just a couple of things to be aware of.

One tip I have heard of when using styro foam is to spray it with water based house paint. You can then use polyester resin over this without dissolving the foam. I haven't tried it myself so you would probably want to do some test pieces just to be safe.

This is good information.

I wrote styrofoam earlier, but I actually meant polystyrene. That's the blue foam that is used to sheath homes right? I hate the white styrofoam stuff because it breaks up into those crazy little balls that stick to everything! Terrible mess and hard to clean up.

Alan, have you used the method described by Syd to build a plug? I would be curious to hear what you think about your current process in comparison. Some things more dificult? Some easier? Cheaper? ... I have never done either so I am soul searching although I am leaning heavily towards a hybrid method of building. The sub-structure (ribs) are mdf panels. Any tight curved areas of the body are polystyrene blocks and shaped by carving, and the longer, straight (and simple curved) expanses covered with flexible 1/8" ply screwed/glued to the formers. The whole thing would be covered with drywall compound and/or filler and then I would use Kilz or Durabild and finish out to 1000 grit with the 6 coats of wax...

I am finding that 3/8" MDF (4'x8' sheet) is $9.80. It's cheaper than the 1" polystyrene board of the same size. With that in mind, my current guess-timate for developing the plug is $400.

Steve, just a few opinions, pros and cons etc about certain materials etc....all IMO of course

White and blue polystyrene/Styrofoam I believe are chemically the same thing. It's just the white is coarser, more expanded and crumblier than the blue.

Drywall filler, very cheap, very easy to sand (almost too easy)...can take a while to dry when cold, damp or applied thickly. Can be be applied over less substantial substrates due to lower sanding force requirements.

Bondo, compared to dry wall filler very expensive, having to mix is a pain, can sometimes go off a little too quickly, dries hard, durable, harder to sand.

Durabild/Duratec, no experience. Seems expensive although no doubt worth it I'm sure.

Kilz, very cheap, dries hard enough to take 1000 grit and can be wet sanded, polishes well, can be applied quite thick with multiple coats, may not dry as quicly in colder climates, but I don't know for sure. Hard drying can be a problem if you sand through as the dry wall filler then sands quickly at the edges.

My best results after some development of the process were obtained by...

Sanding the drywall filler as close as possible to the final shape.

Applying several coats of Kilz and sanding to the final finish.

Some places where I have sanded though I touched up with Kilz on a brush which seemed to work OK.

I have no doubts that Syd's method are more cost effective when time is considered and when multiple molds are needed, but even though I have little time, I have even less money...... and if I need new molds for production purposes I will make a new plug from a thick set of body moldings, which no dobt will have some refinements/tweaks..

Steve!

Don't wish to sound foolish (sod it, who am I kidding, I always do), but have you considered the good old fashioned Blue Peter approach? Sorry English humour!

Chicken wire and wet paper.
You could make the larger expanses with MDF or whatever and just do the radiused areas with the wire. It is very easily formable and if not quite right the paper can be re-wetted and tweaked well before you get to the sanding stage.
Once you have a resonable shape it would be easy to seal and sand. If you applied a plain white paper as the last coat over the old newspaper it would help with the visualization of the plug as well.

Just another possibility and it would certainly be enviromentaly friendly as you could collect all the neighbours old newspapers!
A job for your kids to do as well, so that they can say they've helped!

Terry

Steve to pick up on what Syd recommends, I use durabuild for plug production too, IMHO nowt beats it, no doubt its dearer than Alans chosen method for the raw material but the savings u make on time and effort offset that. The only difference I employ is I finish with the black Hi gloss more often than not, cause I just love looking at my reflection in the glaze when polished with machine glaze/wax nothing beats it. As my old mentor used to say, dont skimp on the finish of the plug and mould and u wont be disappointed with the result.
Shug.

Thank You Hugh. That's likely very sound advice. I think I may try a little of both, just to say I've been there/done that.

Terry, the chicken wire/papiermache is a good idea too. I'll get to that stage and give it a try.

More thrift than poverty Syd..

But thanks, the lottery winnings would come in handy...