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Well quite a while ago I asked if anyone would be interested in a fiberglassing how to. Judging by the repsonses, I wanted to wait till I had a project that would answer alot of questions people had. Well just did one this weekend. And I took pics. Now keep in mind I didn't quite do a step by step because its hard to take pictures while you are working and getting messy. But I will try to explain the steps and if anyone has any questions, feel free to ask.
So to start out, you will need several things to help you with your fiberglassing experience. Most common things are going to be, a box or two of latex gloves, and some very cheap paint brushes. I usually hit the dollar store for alot of this stuff. You will also need some sharp scissors, and mixing cups. I usually use paint mixing cups but they tend to get pricey. So this time when we were at the dollar store, I grabbed a package of plastic cups. Styrofoam cups won't work very well, but the cheap plastic cups they hand out at kegs work great if you double them up. Another nice tool to have is a fiberglass roller. They make several different kinds in a variety of shapes. We usually only use a roller on larger flat surfaces. Otherwise a paint brush will work just fine for anyones needs.
And you will also need some resin and fiberglass matting. I use epoxy based resins. Never tried the polyester based stuff yet, so can't comment on how it works. Fiberglass matting comes in several different styles and weights. They make a chopped strand, which is pretty common, and they also make woven strand. Depending on what you are building will dictate which one to use. For cometic stuff, I like to stick to the chopped matting. And if it needs to be structural, I use the chopped matting and the woven in alternating layers. The smaller the weave pattern, the better it is for forming curves. You can use the larger weave pattern if you are doing long straight pieces.
Most of this stuff can be picked up at local auto parts stores, home improvement stores, etc, in smaller packages. If you are doing a large piece, you may want to check around for online retailers selling fiberglass materials.
The piece we made this weekend is a combination of several techniques, so figured it would be a good one to post up. It will include making a mold of a piece and also ring and enclosure techniques.
So to start out, we wanted to make a mold of a piece in a 67 mustang. Its actually a flip up door that divides the trunk and interior cabin. I assume its purpose is to allow you to carry longer items in your trunk as well as fold your rear seats down.
Here is the car we are working on.
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Here is the area where we will be building an enclosure to hold 2 6X9 speakers.
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Now with being smaller speakers, the fiberglass will not need to be as thick as you would want for a sub box. There is along debate as to how thick a sub enclosure needs to be. We generally like to keep sub boxes around 3/8" to 1/2 thick of glass. Granted this is overkill in most situations, but better safe than having it crack on ya when sound pressure levels get pretty high.
I didn't get any pics with the panel in place or with the panel bare. We were too far into the project by the time I remembered to take pictures. LOL.
So here is the door/panel wrapped in tape.
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Wrapping the piece in tape will alow us to lay the glass directly on the part. This will ensure that it fits perfectly. This is also how you would start the process of making a mold for something. If you wanted to recreate the part, You would make this mold first. Then that would give you a negative of the shape you are wanting to achieve. Then you would simply wrap the new fiberglass piece with tape and lay glass to the inside of this. Then when you pull it apart, you have the same exact shape.
So this is us laying the fiberglass over the piece. The tape will protect the part from getting resin on it. You could also use tinfoil instead of tape, but for this part, we needed it to not move or shift as we worked.
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As you can see in the above pics, as the glass starts to absorb the resin, it will become somewhat transparent. You can see the tape lines very well underneath the fiberglass. This is a sign you are getting enough resin onto the glass and it is being absorbed. If you still have white spots, you will need to get more resin on those areas.
When you are putting the resin down onto the glass, you want the brush to barely slide across the surface of the glass. If you push too hard, you will start to pull strands of fiberglass up. If you have a large surface to do, you can also pour the resin down onto the part and spread it out with the brush. This helps cover a larger area in less time. So depending on how hot you mix the resin (The more hardener you put into the resin, the faster it will cure. They call that mixing it hot.) So you may need to cover a large area before the resin begins to cure. My recommendation for beginners, follow the mixing directions on the resin. If you mix it hot, it will cure alot faster. There have been times when we have mixed it hot and go to put the brush back into the cup and the resin has already hardened in the cup.
You will also notice that we left some extra on the bottom edge that we did not resin in those pics. The reason for that was so we could wrap it around the backside to create a pocket for this to sit in. So when we go to mount it once it is all done, we will use that pocket to hold the bottom and the trim peice that is bolted to the top to hold the top portion. We glassed underneath the trim piece so the fiberglass will be sandwiched between the panel and the trim piece.
![]()
![]()
That is part of the thing that makes fiberglassing difficult. You have to always plan ahead as to mounting or how you want the finished look to be.
So to start out, you will need several things to help you with your fiberglassing experience. Most common things are going to be, a box or two of latex gloves, and some very cheap paint brushes. I usually hit the dollar store for alot of this stuff. You will also need some sharp scissors, and mixing cups. I usually use paint mixing cups but they tend to get pricey. So this time when we were at the dollar store, I grabbed a package of plastic cups. Styrofoam cups won't work very well, but the cheap plastic cups they hand out at kegs work great if you double them up. Another nice tool to have is a fiberglass roller. They make several different kinds in a variety of shapes. We usually only use a roller on larger flat surfaces. Otherwise a paint brush will work just fine for anyones needs.
And you will also need some resin and fiberglass matting. I use epoxy based resins. Never tried the polyester based stuff yet, so can't comment on how it works. Fiberglass matting comes in several different styles and weights. They make a chopped strand, which is pretty common, and they also make woven strand. Depending on what you are building will dictate which one to use. For cometic stuff, I like to stick to the chopped matting. And if it needs to be structural, I use the chopped matting and the woven in alternating layers. The smaller the weave pattern, the better it is for forming curves. You can use the larger weave pattern if you are doing long straight pieces.
Most of this stuff can be picked up at local auto parts stores, home improvement stores, etc, in smaller packages. If you are doing a large piece, you may want to check around for online retailers selling fiberglass materials.
The piece we made this weekend is a combination of several techniques, so figured it would be a good one to post up. It will include making a mold of a piece and also ring and enclosure techniques.
So to start out, we wanted to make a mold of a piece in a 67 mustang. Its actually a flip up door that divides the trunk and interior cabin. I assume its purpose is to allow you to carry longer items in your trunk as well as fold your rear seats down.
Here is the car we are working on.
Here is the area where we will be building an enclosure to hold 2 6X9 speakers.
Now with being smaller speakers, the fiberglass will not need to be as thick as you would want for a sub box. There is along debate as to how thick a sub enclosure needs to be. We generally like to keep sub boxes around 3/8" to 1/2 thick of glass. Granted this is overkill in most situations, but better safe than having it crack on ya when sound pressure levels get pretty high.
I didn't get any pics with the panel in place or with the panel bare. We were too far into the project by the time I remembered to take pictures. LOL.
So here is the door/panel wrapped in tape.
Wrapping the piece in tape will alow us to lay the glass directly on the part. This will ensure that it fits perfectly. This is also how you would start the process of making a mold for something. If you wanted to recreate the part, You would make this mold first. Then that would give you a negative of the shape you are wanting to achieve. Then you would simply wrap the new fiberglass piece with tape and lay glass to the inside of this. Then when you pull it apart, you have the same exact shape.
So this is us laying the fiberglass over the piece. The tape will protect the part from getting resin on it. You could also use tinfoil instead of tape, but for this part, we needed it to not move or shift as we worked.
As you can see in the above pics, as the glass starts to absorb the resin, it will become somewhat transparent. You can see the tape lines very well underneath the fiberglass. This is a sign you are getting enough resin onto the glass and it is being absorbed. If you still have white spots, you will need to get more resin on those areas.
When you are putting the resin down onto the glass, you want the brush to barely slide across the surface of the glass. If you push too hard, you will start to pull strands of fiberglass up. If you have a large surface to do, you can also pour the resin down onto the part and spread it out with the brush. This helps cover a larger area in less time. So depending on how hot you mix the resin (The more hardener you put into the resin, the faster it will cure. They call that mixing it hot.) So you may need to cover a large area before the resin begins to cure. My recommendation for beginners, follow the mixing directions on the resin. If you mix it hot, it will cure alot faster. There have been times when we have mixed it hot and go to put the brush back into the cup and the resin has already hardened in the cup.
You will also notice that we left some extra on the bottom edge that we did not resin in those pics. The reason for that was so we could wrap it around the backside to create a pocket for this to sit in. So when we go to mount it once it is all done, we will use that pocket to hold the bottom and the trim peice that is bolted to the top to hold the top portion. We glassed underneath the trim piece so the fiberglass will be sandwiched between the panel and the trim piece.
That is part of the thing that makes fiberglassing difficult. You have to always plan ahead as to mounting or how you want the finished look to be.
