Wes' teardrop - Fiberglass finished Bondo started - Page 9

[WesGrimes]

I have uploaded all of the build photos in order onto http://wesgrimes.wordpress.com/category/teardrop/

[Ageless]

Impressive how you converted from a mold master to the tear; very adaptive of you

[WesGrimes]

Thanks Ageless,
I was worried about how I would mount it, but it has worked out pretty well. The hardest part was moving the heavy beast.

[WesGrimes]

Got started on putting the fiberglass on finally. I just did a small patch to learn on.

[aggie79]

Lookin' good Wes.

I sure hope it was cooler on the Dallas side of DFW, especially wearing that respirator and tyvek suit. I wimped out on building this afternoon because of the heat and humidity on the Fort Worth side (but I'll be at it early tomorrow morning.)

[glassice]

looking good a few trick I sure you know if that mat is 1.5 oz are thicker You can pull in haft makes it 3/4 oz life easier on corners ,
If havering a hard time holding resin in place use plastic bag to hold in place lay on top and push air out make sure that if the die is on the glass after it get hard wipe of with acetone
To me this was the best tip I ever got is use yellow foam rollers 3"
take a roller handle cut the 2 tabs that hold the roller in place that you can see. then pop the end of the roller out then grind the shaft round so you can thread a locktigh 1/4 nut on it THEN PUT THE ROLLER ON BACKWARD LEAVE the CAP OFF YOU WANT THE BIG HOLE NEXT TO THE HANDEL. When you wet out do in 3" are 4" strips wet dry wet then fell end .that helps hold mat in place if the mat come up with the roller just roll back it should stay do long stroke and do not push down hard . at first it look like it wont wet out but after the mat re lacks that seam to work very well for us. I like to have 3 are 4 roller barrel read and as soon a the foam fall a part put a new 1 on after you are done you can pry the old roller of the barrel

[WesGrimes]

looking good a few trick I sure you know if that mat is 1.5 oz are thicker You can pull in haft makes it 3/4 oz life easier on corners ,
If havering a hard time holding resin in place use plastic bag to hold in place lay on top and push air out make sure that if the die is on the glass after it get hard wipe of with acetone
To me this was the best tip I ever got is use yellow foam rollers 3"
take a roller handle cut the 2 tabs that hold the roller in place that you can see. then pop the end of the roller out then grind the shaft round so you can thread a locktigh 1/4 nut on it THEN PUT THE ROLLER ON BACKWARD LEAVE the CAP OFF YOU WANT THE BIG HOLE NEXT TO THE HANDEL. When you wet out do in 3" are 4" strips wet dry wet then fell end .that helps hold mat in place if the mat come up with the roller just roll back it should stay do long stroke and do not push down hard . at first it look like it wont wet out but after the mat re lacks that seam to work very well for us. I like to have 3 are 4 roller barrel read and as soon a the foam fall a part put a new 1 on after you are done you can pry the old roller of the barrel

Hi Glassice,

Thanks for the tips. Splitting the 1.5 in half will help. I was having an issue getting it to lay flat on the corners. I will try that on the next batch.

Do you have a picture to illustrate the roller mod?

I have a collection of various sizes of metal rollers and bubble busters. I don't know what to do with them, but I have them...

Thanks,
Wes

[WesGrimes]

Lookin' good Wes.

I sure hope it was cooler on the Dallas side of DFW, especially wearing that respirator and tyvek suit. I wimped out on building this afternoon because of the heat and humidity on the Fort Worth side (but I'll be at it early tomorrow morning.)

The trick is to go natural under the Tyvek!

Just kidding! You can see the clothes through the Tyvek.
It was hot and humid, but I figured it is only going to get worse as the summer progresses. Plus I need to get moving if I am going to make Joe Pool.

[glassice]

on any of your metal rollers and bubble busters hold a 3" roller and barrel the nut is so you can change the roller faster if it cure and the handel are a $1 here when I frist start i had ever metal rollers and bubble busters they made after useing the foam roller and chip bursh they whent to the trash . we are doing a willys retractile hard top I thing my camera is in the mold some where again will try to find monday

[kennyrayandersen]

The only problem with building with solid fiberglass is that it is heavy. The trick is getting a shear material (foam or NOMEX honeycomb) between a few plies at the extreme fiber to add strength and stiffness without adding weight (glass plies are heavy and the foam core is light). It’s not easy to do with a curved surface though and especially difficult since you rounded the side corners (looks great though). You could make the center section one piece and make the sides separate and then bond them together if you didn’t have the large side radii.

The center section could be done relatively easily, and the sides as well (in fact they could be done on nothing but a flat table (OK, building a flat table is a challenge)).

You could layup a couple of plies on the inside of the center section, follow that with some precut curved foam (hot wire cut), and then add the inner plies of fiberglass. The pressure could then be applied by a bag from the inside by filling a big plastic ‘bag’ with the outflow side of a shop vac. Otherwise, you just have to shoot on a lot of fiberglass to make up for the fact that each ply is relatively thin and weak (you need a bunch of plies before you get appreciable strength. One thing that is going for you in the side radii is that they are small, which adds strength. It’s the large flat areas that you have to worry about. You could leave the corners solid and add core to the flat areas (especially the floor) for strength.

Also, did you provide some draft so that the molds can be pulled from your buck? These will also need to be able to be pulled from your finished part. You might have to make the mold several pieces if there isn’t enough draft to release the part.

[Vindi_andy]

Looking good wes.

Good luck to you. Interesting switch from Buck to tear proper.

Meeting my Fibregalass lady tonight to pick her brains re the foam core sandwich construction that Im looking at doing.

Good luck and keep going

[glassice]

West your doing a good job
A 5 year old can do fiberglass. please please please try a small pice this can kill you ,your dog burn your house down there seam some of the experts have never done it in real life most that even sell fiberglass suppy this just read something that someone read from someone that heard that from someone at bar said any one can read a book
West is doing this right a little here and a little There
EVEN check what I say.buy a kit for under $20.00 and play with that

[WesGrimes]

Thanks all!

I have calculated the weight of the fiberglass and resin to be 60lbs using the Justin Wilson course in measurement accuracy.

The weight will be worth it for the extra life that it will give it. Also, I think I saved close to that in wood weight as I was able to use really thin stock.

I did not leave enough draft on it to pull a single mold due to all the undercuts. If I decide to pull a mold off of it, it will need to be at least 4 parts.

P.S. I just sanded the first layer of fiberglass, and dang! what a mess. I would talk more about it, but I have to go scrub all of those fibers out of my skin...

[kennyrayandersen]

glassice,
Yes, I've built several parts out of glass and analyzed dozens of them over the years. Like you said, a 5 year old can do it; the shop is full of high school dropouts that can't string together an intelligible sentence and often time unable to read a simple blueprint or ply cut drawing.

The difficulty is designing and analyzing the part in the first place. In order to do that, you have to understand the underlying engineering principles and materials.

There really is a difference between the two. For the FAA (or any other governing body) you need to be able to justify by analysis or by test that any given part is structurally sound. Logistically, no one would build an entire aircraft, test it to failure and then do it all over again and again until they got it right -- it would be way to expensive. One needs to be able to predict beforehand the behavior and failure modes so that the test becomes merely a verification of the previously performed analysis. Do engineers and analysts make mistakes? Sure they do, but we mostly get it pretty close the first time. In 25 years, I've never had a part that I've personally analyzed fail during a test or during a flight -- can you say the same? I'm not trying to get nasty, just saying I’m not an idiot, and not nearly as full of hot air as you imply by your question. Next time you are on an airplane relax knowing that they rarely fall out of the sky (it the safest way to travel to travel!). Additionally, when they do fail, it is usually due to pilot error or lack of proper maintenance – not due to the engineering. Please give it a rest.

[WesGrimes]