Fiber Glassing Tips

[choppinczech]

I came across this tape by accident a while back and thought I'd try it.

3M Venture Tape UL181B-FX Polypropylene Duct Tape.


It's half the thickness of a clear packing tape but strong. Resins, epoxies and body filler won't stick to it. You don't even have to wax it first.

I've come to like it over packing tape or aluminum foil tape for masking. I wouldn't even be afraid to cover an entire mold plug with it. It comes in black, clear or red.

 

[old round fart]

Chop with all these tips I’m wanting to start fiberglassing before I have the roller done!

 

[choppinczech]

I have to share one of my favorite tools for working with glass....

View attachment 21683

... a hand file. But not just any hand file. This is cut specifically for use with plastics, laminates and fiberglass.
McMaster-Carr

It's my go to hand tool for truing up or rounding over edges and flattening. You won't regret having one of these. They're not the same as a metal file.

Here's a cheaper one. It's the "Rapid Cut" Face that both have and make them really cut fiberglass.
McMaster-Carr

 

[409T]

I used to buy those by the dozen from Wurth Louis and Co. and from E.B. Bradley Co. If I remember correctly they were considerably cheaper than $18 ea., probably more like $4 - $6 ea. but that was 10 years ago. When they get full of crap you can have them sharpened, although we used to just put the dirty files in an empty tennis ball can filled with acetone and leave them overnight. That would extend their life quite a bit.

 

[choppinczech]

I used to buy those by the dozen from Wurth Louis and Co. and from E.B. Bradley Co.

You know, probably my most used tool in building this body is a table saw. I'm always ripping strips of materials to use as spacers or to build up a mold or plug. A lot of the stuff I've experienced in cabinet making transfers over to this build.

 

[choppinczech]

You can splice pieces of fiberglass mat or cloth together with fiberglass drywall tape. It's thin and has just enough stick.

 

[fletcherson]

Good tip. That stuff isn’t good for much else, imho.

 

[choppinczech]

Here's a good tip for making templates to match up opposing complex shapes.

 

[choppinczech]

Try stacking layers of duct tape to make flexible sanding pads. It works really well.

 

[fletcherson]

I’ve resorted to many things to sand contours, etc. I took my router and made various concave and convex edged blocks for sanding. It helps get uniform results.

 

[fletcherson]

I’ve resorted to many things to sand contours, etc. I took my router and made various concave and convex edged blocks for sanding. It helps get uniform results.

Self adhesive paper is nice for such endeavors.

 

[choppinczech]

I needed some of this angled stock to use on my doors.



It's made from 4 layers of 3oz. mat compressed in this form.



4 layers of this stuff when saturated and laid up by hand will end up at around 5/16" thick.



But when compressed, it ends up a ridiculously strong and consistent 1/8".

 

[DonnyRay]

Good tips as usual Choppinczech

 

[choppinczech]

I use straight mat a lot of the time. But by itself, it ain't so good for strength. It's really for bulk.

By adding a layer or two of woven glass or a core material, the stiffness and strength increases massively.



That's what makes material like biaxial 1708 so strong.



45° strands that are stitched to a 3/4 oz. mat. The combination is crazy strong.

 

[DonnyRay]

I've used it before. It's great stuff. If my memory is correct , it soaks up alot of resin. I've also used core mat. Core mat is great for cutting out detailed shapes.

 

[old round fart]

Hey DonnyRay! I think your style is catching on!

 

[MMC757]

I had a real learning experience last week.
I've done some fiberglass work in the last few years in Ohio and in Connecticut, both in warm weather.
Last week, I was visiting my parents in Arizona and helped my dad with some repairs to his C-cab body.

The difference in work time for resin was REMARKABLE!
In the humid environments, I've got maybe three minutes before my resin starts getting a little gelled up, about four minutes until its totally worthless, its ready for more coats in maybe 20 minutes, and ready for sanding in probably 40 minutes.
In AZ, I was easily able to work with the resin for ten to fifteen minutes or more and the dry time until I could sand or add another layer was MUCH longer.
Temperature in the garage was probably mid 70's with no humidity, and I was using the normal off-the-shelf resin found in home improvement stores.

 

[raidmagic]

How are you guys mixing up larger batches of resin? Can you show me some of your mix buckets and mixing tips and tricks? I glassed my body to my floor and it was tedious to say the least.

 

[old round fart]

I’m going to try the UV activated resin. Brand name Sunflash from Amazon. It’s a little higher but no waste is a plus,

 

[choppinczech]

How are you guys mixing up larger batches of resin? Can you show me some of your mix buckets and mixing tips and tricks? I glassed my body to my floor and it was tedious to say the least.

One thing that helps with resin setting up too quick is to use flat trays. I'll mix up 16 to 24 oz. at a time in a mixing tub and then pour it into an aluminum tray or a paint roller liner.

The same amount of resin in a deep tub compared to a shallow tray sets up way faster. Something to do with the isothermic properties. It works with brushing or rolling the resin.