Hey everyone. Question about molds

[kitcarguy]

Hows everyone doing today?

I have a few questions, not related to boats, but related to molds and fiberglassing in general.

I recently obtained a set of molds to build a car. They are very solid and in great shape, but a little dirty. What would be the best way to clean these up? Also pertaining to building a body in general what is the best method? Should the body be hand laid, or use a chopper gun? What are the advantages or disadvantages.

Also what type of skill level do you think is needed to lay the body? And last question is what do you think the cost of materials would be to do this?

Here are a few photos









Thanks again for your help.

[kitcarguy]

This is the second time I have posted where nobody will help me out. Im just looking for general information, and was hoping a member of this great community would chime it.

[SamSam]

You might try putting the question in the "Fiberglass and Composite Boat Building" section of the "Boatbuilding" forum. Here it is...

http://boatdesign.net/forums/forumdisplay.php?f=20

Once your there you can also try "search this forum" with "molds" or "mold preparation".

If it's just dirty, try dish soap and water, nothing abrasive. The object is to not to scratch it up. It would probably be best to strip all the old wax, re-wax with 4-5 coats and then a coat of PVA to get it ready for lamination.

It depends on what the body is for and if weight is a factor. Hand laid with strategic reinforcements and foam cores will be strong and light but take longer and cost more. Chopper gun will be faster and a lot heavier and more or less stiff/strong depending on how much is used. It doesn't look like there's been a chopper gun used on it. If there had, there would more than likely be some or a bunch of glass fibers stuck on the framework and the outside of the mold. Chopper guns are messy.

It will take a good amount of skill to do as it's a complicated mold with a lot of inverted and hidden areas that will have to be gel coated and/or laid up and worked almost blindly. If the thing was able to be rotated it would help a lot. Not too many can work on it without getting in each others way. 2 people working the glass with another supplying materials would be swell. After making 2 or 3 bodies you would have a real good idea how much reinforcement/glass is need and where and how to go about making it.

[kitcarguy]

Thanks for your reply. Well for an example here is a completed body out of the mold.



This gives you an idea.

As far as the main body goes, it does just appear dirty, and a little dull. Some of the other pieces have a great shine to them.

[SamSam]

Do you have access to that completed body? Can anyone tell you what the layup was?

If the mold is dull, it needs to be buffed and waxed.

[kitcarguy]

Yeah I am purchasing the completed body in a few weeks, as well as a chassis. The gentleman was not sure if it was hand laid. I will see once I get it. I dont know that I will ever pull another body from the molds but if someone has an interest I might try, or find someone local who can.

It was just a really good deal that I could not pass up.

[SamSam]

What model is it? Is it a race car?

[kitcarguy]

It will be a street car. Thats what it was built for. I wish I had more information but you now know as much as I do .

Here are a few more photos

[fiberglass jack]

I take it you will be painting the car after your done with it, if thats the case you dont need a super shiny mould as you will be sanding down the gel also you will want to use a sanding gelcoat to lay up the parts, ant car moulds i make i sand with 600 and buff and a few coats of wax, you should use pva everytime you lay up this will stop any wax transfering to the parts, wax will give you fisheyes, go with hand layup chopergun is to hard to control, also you want to spray the gel even so you dont end up with pre release around the corners if the gel is thin it will wrinkle on you, if this hapens u will be going to town with bondo, another thing to look out for is print throu do not use 18 oz or 24 oz roven , we did a 67 stingray and the customer insisted to use 18 oz told him it will print throu he wouldnt listen, has had that car paint a few times and the checker comes back like a goast, most kits are made with polyester resin except for carbon fiber that is epoxy

[SamSam]

Originally Posted by fiberglass jack

I take it you will be painting the car after your done with it, if thats the case you dont need a super shiny mould as you will be sanding down the gel also you will want to use a sanding gelcoat to lay up the parts,

What is 'sanding gelcoat'? I made some front ends for a racecar once and skipped any gelcoat on one to save weight and the guy wanted to paint it to match anyway. It came out with a few billion pinholes in the weave of the cloth. Is this 'sanding gelcoat' the only way to get around the pinholes?

[kitcarguy]

yes I would also like some additional info on the gelcoat

Also in everyones expert opinion, what type of mat would you use to do this body?


Anyone in the orlando area want to show me the ropes with regards to molds, and pulling a body from one?

[fiberglass jack]

sandinggel is a gelcoat that is soft and sands easy, u should be able to get it at any fiberglass sulplier they may have to order it , it will save you alot of time, what type of material do you want to use? how much money do you want to spend, in the past i have seen kits built with 5 layers of 1.5 oz choped mat which is cheap and have built using prepreg carbon and nomax the photo is a car we built using carbon and nomax core

[kitcarguy]

Looks a lot like a radical SR series car .

Well Im going to find someone local to me once I get them all cleaned up to give me a few pointers .

Thanks again for all your help Sam and Jack

[fiberglass jack]

place a add on craigslist

[kitcarguy]

Yeah I will do that.