1/8th Mercury sedan

[Palat]

Hello people

Just to spice up this project, i have created a mild sled version of the Merc, shaving and adding lakepipes/Appleton spotlights. The grille is from my 54 Chevy model (doubled the "teeth"). Hope you like it!

[xken]

Just ran across this thread, my 2 cents again....

I'm pretty much sold on going with glass......the body could be kepi fairly thin and it would be a lot lighter than resin .....opening doors, hood and trunk lid would have the rigid structure it needs to keep everything where it belongs.

I agree with everything you are saying about fiberglas and it's advantage over resin . However, I have had years of experience working with fiberglas making both small and full size car molds and parts. And I do not know your experience level on working with it; so please bare with me. So again my 2 cents.

One alternative that you may wish to explore is using epoxy instead of polyester resin with glass mat. Why you wonder, epoxy is not as fickle to humidy and gelcoat orange peel . It works the same way, and is more forgiving in thick areas and stable not causing the oil caning due to uneven polyester resin shrinkage as it cures. Also the epoxy does not have the shrink rate that polyester resin has. I will try and find a link later on. Also does not smell as bad.

Here is a link to Freeman's: http://www.freemansupply.com/Freeman601Economic.htm you will also want to look at their 701 surface coat (gel coat). Other suppliers may offer in gallon cans; these guys only offer in 5 Gal. cans.

[B]Fiberglas tip;[/B] if you are working with it; take large doses of Vitamin C before and while working with it. Styrene monomer (which is what you smell) accelerartes the killing of red blood cells; which in some people causes headaches. Vitamin C counteracts this effect.

[B]A bondo tip;[/B] if you wish to cast parts with bondo, thin it with fiberglas(polyester) resin just to the consistency of pouring. The reason for as little as possible is due to the shrink rate of polyester which is about 5% typically. The thinned bondo mix can now be cured using the bondo hardner. This method is good for casting parts with non critical demensions again due to shrink rate. Or for backing up molds for extra strength, and thickness, mix with excellsor.
Also thinning the bondo more you can do hand roto- casting so as not to have a solid part. Just keep turning the mold until the mix kicks off and hardens. Usually one section will be thicker once cured. I have cast 4 inch diameter tires using two part molds. Poured mix through inside hub location hole and taped hole over with masking taped and rotated by hand. Watch the extra mix in the cup for when it is hard. Just keep in mind the thinner it is the more it shrinks.

Based upon having killed many red blood cells and perhaps a few brain cells too!

Ken

[Daytonatim]

Man, that is one nice looking ride Dan. I see you have added an interior now too, looks good!

If you get a chance Dan, you ought to post up some of your boats in a boat thread. Your creative work might just provide some inspiration to someone.

Ken, what is the cost comparison between polyester and epoxy resins?

[hot ford coupe]

That's the kind of Merc I would want to have. That's gorgeous Palat. I definitely wouldn't mind being seen in one of those on the highway.

[xken]

The initial price of epoxy is probabley double the cost of polyester; however if you look at quality, time, effort and scrap rate epoxy is a better deal in the long run.

Here is a link to study more: http://www.shopmaninc.com/resins.html

The other factor is workabilty, epoxy will stick to anything and is itself easily repaired or attached to. The same cannot be said for polyester once cured with other materials.

There is an old saying about a purse and a sow's ear; sometimes in the long run initial price can really cost you in the long term.

Again based on my own personal experinece with both I would choose the epoxy over polyester regardless of cost. Especially if I am trying to build a scale car body with built in recesses to accept doors, windows, hood and trunks, and all thin walled as well. Perhaps this is why all the high quality, lightweight kyaks are made using epoxy rather than polyester.

Nothing beats the right tool for the job! The same is true for materials.

Ken

[Don Garrett]

Most of my experience with glass has been full size old school stuff. I'll leave it to you guys that have more experience to set the standard. Ken.....2 cents isn't enough for this kind of info, thanks.
Tim, Dan......now we're getting somewhere. The chevy grille, smoothie bumpers or rolled pans, spots, hub caps, lakes could all be part of a trans kit for the base Merc body.

[hot ford coupe]

Hey Ken, looks like the epoxy is the right fit for the job. Initial cost is sometimes not a great barometer for the long term.

[MADD FABRICATOR]

Ken, Just so you know where all this started from, I was the one who originally suggested using polyester resin in place of the two part urethane resin most small parts caster are using. This came about because for almost 50 years I have worked primarily with the polyester resins when building 1/8th scale car bodies for my radio controlled race cars and a few model hot rods. A couple of reasons I went with this material was (1.) it was easily purchased from just about any automotive parts store and even Wal-Mart type stores, and the epoxy resins were pretty much a limited source, especially if you didn't live near a boat marine supply place, and priior to the internet purchasing capabilities. (2.) Cost was also a major issues when living on a small income, and trying to keep the kids clothed and food on the table. Epoxy resins were twice the price and I was also forced to buy quanitees much larger than I needed, thus a waste of product. (3.) I became very comfortable working with the polyester resin and the shrinkage issue was not a factor in what I was laying up. ( even bodies were not a factor as most people would never notice the shrinkage that took place.)
I will agree that epoxy resin bodies would probably be better because I've seen some large size r-c aircraft fuselages layed up with only one or two layers of cloth which creates a super light weight assembly. The down side is you do have to have some reinforcements located within the body to prevent warping and distortion.
Thus we get to the Merc. If layed up in a light weight manner, it will need the inner fender panels, firewall, trunk bulkhead, and rear inner fender panels installed at time of initial lay up. These would need to be installed prior to removing the body from it's multipart mold. This would gurantee the quality of the article that TDR and of course the buyer is looking for.
I would also recommend that a scale frame and suspension components be provided/ made available as oppossed to trying to adapt some other kit frame. Using an adapted kit frame would require the builder to purchase a complete kit or junk parts to just get the frame and suspension, which would be another added expense to those who don't have a junk box of parts.
This type of quality will of course come at an expense to the buyer, but it would be worth the cost to not have to " correct" the type of deficiencies that the modelers have had to experience to this date. This is not meant to " slam" anybody as to the quality of the products that have been sold on the after market, but to state that times are changing and a new day has arrived for the person interested in building 1/8th scale model cars.
We are very lucky in our lifetime to be able to have this venue available to us. So lets all pitch in with our thoughts and concerns and make these products the best and most correct on the market.
Just my .02 worth.
CHEERZZZZ !!!!!! ( M.F. )

[xken]

I agree with most of what you say, polyester is better than the urathanes; and epoxy is better than polyester. One point with epoxy is that after curing it bonds to itself with no problems; so inner fenders and such can be added later. I think the point you make is that regardless of material used some form of truing up fixture is needed to maintain squarness until attached to frame. My background was from the commercial/industrial side of prototype development for a major corporation where speed and labor cost were the main concern and not material cost. So people should be using what they know and are comfortable with based on their knowledge and buget. Regardless of whether polyester or epoxy is used both can be screwed up very easily with lack of working knowledge. My input is only intended to be advice and awareness based upon my personal experience; and the one good thing about advice is, that people do not have to take it.

Just a couple of techniques with epoxy ; after surface coat (gel coat has been applied, cut and fit glas cloth or mat as required and dry fit keeping overlap to a minimum, then apply epoxy with just enough to wet the glas or mat, try to avoid puddle build up; if you get a puddle, remove excess with a brush. Let kick off. Now if you want a smooth surface on the inside, mix and brush on the surface coat (gel coat) while still in the mold. Let kick off and sand smooth in the mold, using the mold as a buck to hold the shape. This can also be done after de-molding too.

To make flat panels spray mold release (PVA) on 1/4" plexiglass or glass plate- 2 pieces; cut cloth or mat to desrired size, lay down on clear plexiglas or glass sheet and wet with epoxy . Then carefully lay the second piece (mold release side to epoxy ) down on wetted glas, and press grently until even and let cure . If a specific thickness is needed use shim stock the desired thickness to stand-off the second piece of plexiglass. Let cure and then pry apart. This makes basic sheet stock with both sides smooth.

Specific shapes can be made this way as well by cutting the desired shape out of styrene stock; positive or negative and follow the same steps as above, use mold release on all materials that are not epoxy . Cut lines can be scribed into plexiglas and be molded right into the surface of a sheet. Pockets and recess panels can be done the same way.

For old school types like me that have used modelling clay like used in the automotive industry here is a useful tip. The automotive clay has an oil in it that will cause no end of grief, which is why for decades they used plaster to make molds, then drove the water out of the plaster with a 7:1 mixture of thinner to shellac to seal the molds. This process as you can well imagine took days to do. Now here is the short cut; once you have your clay model done, and slicked the surface down with hand clearner; get some spray LATEX paint. MUST be latex to seal oil. Craft stores sell it. After a couple of layers being sprayed to seal and dry then spray the PVA (green stuff) mold release on the latex a couple of times. Then brush on the surface coat (gel coat) then glas and reinforce as desired. The beauty of this technique is that you can mold in door, hood, trunk recesses as deep as desired in the clay, make your mold then go back, replace the clay and make your finished surface mold all off the same clay model. Folks I personally have done this technique with full size cars to make molds and finished panels. It saves a tremendous amount of time by getting the recesses required molded in the first time. One word of caution if using polyester; use a slow set to avoid heat build up; if you get too hot it will deform the clay.

That is a enough for now. Sorry did not intend to start a book.

[MADD FABRICATOR]

Ken, great reply. I for one, appreciate hearing your comments and tips for working with the epoxy and polyester resins. We are most fortunate to have you on this forum. It sounds like you've gained much experience with working with those products mentioned. Sad to say, most of my learning curve was by the old " trial and error" method, where as living in a small town, I knew nobody in person with whom to share ideas and thoughts. In my earlier days I had lots of clay and plaster patterns end up in the trash for lack of knowledge.
You bring some fresh ideas and thoughts to the 1/8th arena. Looking forward to getting your expertise as we more forward with the long desired projects.
Looks like I need to do some research on acquiring some epoxy resin and do some experimenting with that product. I guess it's time to expand my horizons , " start working outside of the box ", and see what this epoxy is all about.
Many thanks for your input !!!!!
CHEERZZZZ !!!!!! ( M.F.)

[xken]

I will soon be 62 and I still try to learn something new everyday; or better, share some of my lessons learned. My first experience with polyester fiberglassing was in 1963 helping a friend build a kyack while in high school. Then received formal training in the Marine Corps as a Helicopter Structural Mechanic, on CH 46's many access pylons were fiberglas. Then in college I designed and built scale models of products and one full size car for the Clean Air Car Competion in 1970 at the GM proving grounds in Milford, Michigan. In fact, GM sent several of their model development teams to visit the school to learn the process we used and took it back to use for their purposes. As students we did not know better, but being art students we knew latex was a plastic sealer. One thing I have learned over the years is that necessity is the "mother of invention" and that no one has a monopoly on creativity.

Visit the Smooth-on link in the tutorial section, they have some great how to's. Also visit the Freeman's link on the previous page; I think you can purchase sampler kits from them on various materials.

Have a great day! Ken

[MADD FABRICATOR]

Ken, thanks for the background info. I'll drop you an email later.
CHEERZZZ !!!!! (M.F.)

[Don Garrett]

Ken & Madd,
You two have made my day. Back when I hooked up with Dan, 'bout 3 years ago, we wanted a site where everybody could play, beginner or master craftsman, young, old whatever.
Thanks guys..........think a chopper gun and maybe a sprayed metal-flake gel coat....aw, there I go again.

[xken]

Check out the Smooth-on link. You can add metal powder to the Color Match resin and cast metal looking parts for engines and accessories.

[hot ford coupe]

Just think for a minute. It's been 3 years since this forum was started and look how much talent and expertise we've gained since. With guys like Ken and Madd,( and a bunch of others-you know who you are) I'm proud to be a member of SMC