Scratch Build – In Progress SSR-X: Update - Bottom Cover Fiberglass Part 2/De-Mold

This is utterly bonkers! I love it! Can't wait to see more. (and serious skills to get all those plates accurate.)

 

Thanks bro! Great words from a Masterer Modder. Everytime now I'm sandin filler I think abt your current project and all the fiberglass.

Thanks! It is ridiculous in a way

 

Update: 3M Short Hair filler

Its been a busy day in the laboratory...



Started the activites with the hand grinder.





Worked on grinding down the welds and access filler. I completely grinded down the bottom cover so I could move my hand across the cover without any major bumps.



This is my first time using short hair filler. From what I hear this stuff is really strong. Been thinking about possibly using this as a backing for the upcoming mold, though, dont know yet. Still pondering on it...









I got to work on some loose ends and seams that kept breaking. I didnt want to re-weld those spots, so I figured I'll try out short hair filler and see how it holds. The filler comes out of the can really thick, about twice as thick as regular filler. I filled the end that will later get grinded and sanded down to match the top cover corner where the meet one another so they are symmetrical.



Next task was to tackle those inlet covers.







Cut, taped and flipped to get ready for filler.



Gettin ready for the inlet covers wanted to show off the short hair filler. Reminds me of a toxic waste in color







I made sure I sanded the areas first for better cohesion and than I waited and waited!!







Finally after the short hair filler dried I was able to take the cover outside to finish it off with regular filler. The weather got nice today around 55F and I wanted to avoid stinkin up the shop.

I highlighted with a circle on the covers where I needed to go over. You probably will not be able to make it out. Just mentioning because it was a new task I did, which, helped me remember all the areas that needed attention.

Doing a final sanding tomorrow and this cover maybe ready for the mold process

back tomorrow.

 

This thing looks insane. Glad I am not sanding that thing.

 

Thanks! sanding is not that big of a pain anymore, 3M sands pretty fast.

 

Thanks for your kind words my friend, I see you have your first experience with the liquid fiberglass! I used 3 different types of it on Project Synthetica and also 3 different types of isopon which is the finisher. I will tell you one tip though. You can make the material thinner and easier to work with in this way. First take some fiberglass and place it on a spatula and by using one more spatula work it well Without applying any hardener! Once you mixed it well apply a tiny tiny bit of hardener in order to have the time to apply it before it gets hard. The fiberglass doesnt gets hard with temperature but with the amount of hardener you put in. Apply 1 more layer after it dries and when its finished sand it and use your isopon (car filler) to hide any imperfections! Hopefully I could help a bit!! Mod on bro you rock!!

 

Update: sanding

Hello. Been busy sanding away. I was suppose to update a couple days ago, but just have to been too heck it lately... so anyway





These coats are the initial coats of filler onto the covers. I waited until they dried and than sanded.





After sanding I went back over the covers with my hand and felt for areas that needed more filler. I marked them out with a marker. Some more pics below.











I emphasis this because the mold needs to be near perfect if not perfect when doing a material like CF. Any little bump or ridge with be captured by the molding process and transferred to the cloth. It is time consuming but it will reflect itself in the final product. I pay close attention to details myself. So I endlessly am rubbing my hands over the covers which some ppl look at me like I am wierd but it is the good trait god gave me.





Same process. I marked the cover and begin to apply filler for the next sand.









Right now I am currently finishing up sanding and making some changes to the cover. More on that this weekend.

 

I love this thing. it looks like very soon it actually will be ready for take of....nice work.

 

OK. Let me get this straight. This whole construction is just a mould? If so, why didn't you use MDF instead? A lot cheaper and easier to work. By the way I love the shape of that thing.

 

The shape is awesome! Loving it!

Can't wait to see it finished! How much time has it already eaten up?

where's it going when its finished?

 

Awesome and very unique, I really like it.

 

Thanks!!

Good Question! First, They dont make MDF in .040. Second, you shouldnt make a mold out of MDF due to its texture. I originally hunted down for large sheets of Basal wood but could not find any. That way I could have just glued the whole structure together. It really came down to cost, Basal in small pieces was expensive. As for trying to make it out of MDF or something with a greater thickness wasnt just practical from the standpoint of checking the clearances. You dont want to make a mold and than make the frame after making the mold because if there are any mistakes or such than your mold product is garbage.

Also, the geometry is very complex. Making sure I could be redundant in checking clearances and pathways once again was important to me. I did a render in Google Sketchup though and what you see on Google and what your fabricated build turns out to be could be too different things becz of the construction method. Right now as I build I am constantly re-rendering the build in my head. Looking at where I will have to cut frame pieces and add support brackets.

Thanks for the Support, esp. from you!!

Thanks. Mountain of time! hahaha, good question, umm somewhere in my small apartment, it is going to look completely awkward, lol.

 

Looking good

 

This is shaping up REAL nice !
Great work man !

 

Thanks!!

Thanks!!


Modders Note: The top and bottom covers are 99.5% done with sanding. All that is left is to do the ends which culminate at a point than it is off to the Mold process. This process will change the way this Project Log is written in that a comprehensive Tutorial will be done on the process for such a large piece. The covers do measure 80" by 36" so by no means is this a small mold in the computer modding world. It is Thanksgiving week here in the USA and I wont be getting underway on the process until sometime next week, at least. I'm excited and eager for one of the most sections of this build is upon me.

 

Mold Making Tutorial

Mold Making Tutorial

This tutorial will go over the process of making a mold for your project. Whether it is a small mold or a big mold, such as, mine is, this tutorial should give you insight and time-saving research into how to make a mold. I will list the materials needed and the pros and cons of the mold making process and what variable's to watch out for. I personally tried to hunt down a good tutorial on the internet and couldn't find one, so now I am writing one.

References:

http://www.compositescentral.com

This is a great website to go-to for information and help on making molds and composites materials in general.

http://www.carbonmods.com

They have a great youtube video on making a mold.

List of Materials Needed:

1. The form you are going to make a Mold of
2. Partall Wax #10
3. Partall PVA
4. Gelcoat: Polyester or Epoxy
5. Reinforcement: Fiberglass or Putty
6. Non-Hardening Modeling Clay
7. Gloves, Mask, Razor Blade
8. Wieghing Scale

Here is the picture of the material that I will be using

The Mold Making Process

Now that you have assembled your materials, A plan needs to formulated for how to construct your mold! Remember always take your time and have patience. Rushing into the mold making process can lead to failure down the road.





Make sure you have a flat sturdy surface followed by a material that you can apply Wax to. In my process, I chose Whiteboard from Home Depot due to the size of my mold. The cost for a piece of Plexi-glass or glass would be too costly for me. This whiteboard is coated with a ceramic paint which is intended for bathroom construction involving water, so I will be able to wax this surface.

You can use a bare wood surface, though, I have been told not to due so, due to the porosity and texture of the wood could cause a mechanical lock and make the mold surface not flat.

What is Mechanical Lock?? Mechanical Lock in a mold is where the bonding surface such as, Gelcoat binds to the Form that you are making a Mold of. In the end, you will not be able to release your form from the mold thereby creating a lock and potentially ruining your mold.



Place your Form/Part on the base board. It should sit considerably flat. Ideally the flatter your Form sits against the base board surface the less modeling clay barrier you will have to use.







The next step is placing modeling clay along all the edges of the Form that come in contact with the base board. Pretty simple task. Use non-hardening modeling clay from any arts and craft store. Roll into a round long bead and push and stick on the edge than flip your Form and push it onto the base board.

I tried this method and than tried to flip the Form over and the clay fell right off. Time to improvise a new solution.



I took my Form and traced an outline onto the board than I applied the modeling clay along the outline of where I knew the edge was going to be.





I took the Form and placed it onto the modeling clay and very carefully pushed down into the modeling clay the best I could.



I went around the edge of the Form trimming and adding modeling clay where needed to prevent the mechanical lock from occurring. It is BEST to try and have no gaps between the modeling clay and the Form's edge. Try to make the surface of the clay the smoothest you can.

The next following Steps in the Mold Making Process are crucial!! Here is the Basic Method:

1. Wax : 5-10 times with buffing between each wax coat
2. Apply PVA: which is mold release agent. Typically 1-2 coats.
3. Apply Gelcoat: Millimeter thickness depends on your plan
4. Apply Reinforcement: Fiberglass or Putty like substance
5. After Mold is cured: De-Mold

Partall Wax #10 is the most commonly used wax on the market in the mold making process. There are different wax's, please do your research and be informed about how these other wax's could affect your mold making process. This wax is economical in price, about $10 for this can here.

Apply your wax coat and wait for the wax to dry and than buff the wax coat. Your drying time will depend on the temperature, humidity, and wax vendor you are using. Once again you will want to do this at least 4-5 times before applying PVA.

Wax helps in the releasing of the Form from the final mold. The more layers you apply the easier the De-molding process will be.













PVA: polyvinyl alcohol is used as a release agent in the molding process. PVA will create a barrier on top of the wax for further release help in the de-molding process. Using PVA is MUST in the mold making process.

Please where a ventilation mask and gloves when using this product. Make sure you have adequate ventilation. PVA does not smell good and is sticky on bare hands.

You can apply PVA by either spraying in onto the Form or you can rub it on with a cloth. Spraying will lead to shorter drying time while the cloth method will take longer. Spraying is about 15 min. depending on the thickness and environmental conditions, while cloth is usually around 45 min. Don't spare the PVA, this stuff is economical, $20 for this gallon.

The application is also simple. Simply just rub on the form surface making sure to go over the entire surface esp. the corners. After each coat wait for the coat to dry before applying the next coat.

I applied 3 coats to my Form.











After the Wax and the PVA have been applied it is time for Gel-coat. What is Gel-Coat?? Gelcoat is the actual finish mold surface of your part. It should be as smooth as possible when finished curing. In the process of mixing and applying Gel-Coat you can get tiny air bubbles. Depending on the type of Gel-Coat you are using, will determine the probability of developing air-bubbles.

There are two types of Gel-Coats: Polyester and Epoxy.

Polyester gel-coat is used when no backing reinforcement is needed. It drys to a non-tack finish, hard, high gloss finish. If attempting to use a backing reinforcement, a primer coat is needed for adhesion between the polyester and whatever backing coat your are using. This is typically NOT done this way. I have found that this is mainly used in the boating industry for repairs on the outside of fiberglass hulls.

Epoxy gel-coat or surface coat as it maybe called is used when a reinforcement layer is needed. It also drys hard, but tacky, with a glossy finish. Epoxy is suited more the tool making industry in which molds need to be made and used over and over again.

There is alot more science behind the two gel-coats. Do your research and determine what is best for you and your process. If you are making a mold like mine, Epoxy is preferred.

The application is a little in-depth. You will need a wieghing scale and some cups and stirrer. The material you are using will have a mix ratio, usually done by wieght. Gel-Coats are made of Resin and a Hardener, where you will have to mix to the two. Some basic math will have to be done. I am using RenGel 1118. It has a mix ratio of 100:9 by weight. So 1 lb of material Resin will need .09 lb of hardener. Make sure to Tare out the cup/container you are using so not to throw off your mix ratio and to insure the proper mix.

Mixing the two together can be simple or difficult, depending on the density of your material. The thicker the material the more stirring is needed. Which means the more chance for air bubbles and vice versa. It is generally recommended NOT to mix to rigorously. I had to mix rigorously due to the density of RenGel 1118.

Once you have mixed your Gel-Coat you are fighting against time. You will only have so long to apply your coat before is drys. It drys Hard. The time can vary depending on your product and conditions of the room environment. RenGel 1118 has a 30 min. gel time. The last picture above is Ren gel-coat.







I used a bristle brush to apply the gel-coat. I tried to make it as uniform in thickness as I could. I got about 1-2mm thickness out of the coat. You can apply more if needed. It is recommended to get the corners with thicker coats due to higher stresses in those spots when the mold is being used. RenGel is expensive. $49 per quart of Resin with $16 for the hardener. I used two quarts on this cover. Each Quart can cover 900 square inches approx. Your product may differ. Once done just wait for the gelcoat to dry. This is epoxy coat so the surface will remain tacky so a reinforcement can be applied.



All-Fix is a two part putty the hardens. There is little shrinkage in the product, so the chance of cracking is rare.

The more common material used for reinforcement of a mold is Fiberglass. I did not chose fiberglass due to cost, health concerns, and that air bubbles can burst thru your gelcoat. I dont have the necessary ventilation and equipment to due fiberglass, which is my health concern. The cost between fiberglass and All-Fix was almost the same. The air bubble effect is what concerned me in the end. This phenomenon has been reported over at Central Composites by other users. When they de-molded, they found bubbles had burst their way thru the gelcoat leaving a cavity in the mold surface. They typically have to start the mold process all over again. Fiberglass application created a exothermic effect. It created heat and alot of it. This heat can cause your gelcoat to break down and air bubbles to push thru. Due to time and cost I searched out a alternative solution which was All-Fix. Carbon Mods uses a similar substance in their mold making video.







After mixing All-Fix putty I applied it to the gel-coat. Simple application in just rolling it out on a flat surface and placing it down and patting it down. I made sure that the reinforcement layer was really thick. The cure time is 24 hours.

So.......I ran out of All-Fix and I substituted in Short Strand Fiberglass filler in for the All-Fix.

This was a solution presented to me by my cousin. He had done the process this way before. The short hair filler still gives off heat so I placed a fan above the filler to help cool the filler off while it was drying. This material will dry to the hardness also that I desire, since I have already used it in gluing edges together on the underneath of the covers.





Now I wait to De-Mold and see if the process is successful.

Questions and Comments or advise don't hesitate to ask or write.

I hope this tutorial has been helpful to those looking for guidance and information on the mold making process.

 

great work man keep it up (=

 

Good mold-making tut!

Be sure it's 75 degrees or so in there when demolding, the warmth helps the gelcoat separate. If it's recalcitrant, you can also put ice in the metal shell, and let it shrink the interior so that it pulls out cleanly.

 

Dude this is sweet. Top marks for effort, detail and an all round brilliant work log. Sub'd

 

Thanks

Interesting trick!! Thanks for that info.

Thanks for your support!