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Tue Jul 24, 2007 5:55 pm

On my buggy the rear shock tower was hitting the inside of the spare tire well molded into the back seat area so I cut away the problem area put in a patch for more clearance.

I used wax paper for the mold contact surface with some bits of plywood & a piece of plastic pipe held in place with duct tape to support the wax paper.

I have found wax paper is stronger and gives a better release than saran wrap.

Here's how I did it. The object of this first step is to establish the shape then add a finish layer on the front and add a reinforcing layer on the back.

Wax paper taped in place:

]

Plywood mold support. You can use anything here, its only function is to support the mold surface.

View from the front side

Glas in place

Resin applied. Didn't turn out as smooth as I hoped, but I expected it would need further finishing anyway.

View from the back after removing the mold. Some of the wax paper is still stuck to the surface, no problem since it needs another layer anyway. It will clean off easily with a wire brush in the side grinder.

Now for the question: I am using finish coat poly resin which leaves a wax on the surface which must be removed between layers (and presumably before painting also). Normally this is done by sanding. Can a use a wax remover instead especially for those areas which are difficult to sand? If so, what wax remover should I use?

The project, BTW, is a Bow-wow "Boomer" on a '59 pan with a 72 dual port engine. Parts are from all over...steering column complete with ignition, lights, wipers, dimmer, etc. is mid '80's Nissan pickup , speedo & seats are Super Beetle, Tach is from a 4WD Lada (hope it works) & several other sources for other misc bits.

Tue Jul 24, 2007 7:00 pm

If you have another repair...Try using duct tape to make the shape, add resin and then mat, more resin and so on...when your done peal back the tape....I have found the duct tape breathes a little and the repair cures very well.

Tue Jul 24, 2007 8:53 pm

I have no problem with the resin curing as long as I use finishing resin. Laminating resin takes much longer.

I have used duct tape to make the shape but I had problems getting the mold to release because the f-g bonded to the duct tape. I would have had to wax the mold to get it to release, I wanted to avoid this extra bit of prep so I used wax paper.

There are many different duct tapes available however, there may be one with a surface that does not bond to f-g.

Wed Jul 25, 2007 8:21 pm

Actually what you wanna use is Foil Tape. Polyester does not stick to aluminum will give you the best release of all.

The wax remover won't work, hwever Acetone will. Just wash it down good, then repeat 2 more times with a fresh rag each time until it's no longet sticky. The just scuff with 36G by hand and it will be prepped enough.

One of the easiest things to use to scuff with is those Fibre Grinding disk. Just don't let it slip in your hand as they will cut you. It will rip the surface a new one pretty easily.

Thu Jul 26, 2007 8:20 am

Thanks Elwood.
Perhaps next I will try aluminum foil instead of wax paper for mold, should be able to crinkle it to follow a complex shape although if the resin seeps under the crinkles it may cause some problems.
Will try acetate to clean the wax.

Thu Jul 26, 2007 5:35 pm

Foil Tape ! It's available at home Depot and Lowes. It peels of and is stiff enough to bridge gaps and make shapes and sticks well. The resin will not eat the adhesive. Foil will work but what happens is the resin will seem into the folds and will tear apart when you go to remove it.
Trust me on this I use alot of Foil when sculpting and sometime I gotta hollow out the back and removing the foil is difficult.
Stick with the tape and squeege it down, you'll be very pleased with the results.
Works great for repairs and filling holes to. Just back the hole and glass it in. when it kicks peel the tape for the back or front and and it's smooth.

Not really expenive if you compare the amount of work it will save you like 8 bucks for a roll.

When i stretched my Buggy body I formed some Cardboard to fit the body contours and covered it in Foil tape. Propped it up and screwed it to the body with wood blocks behind it. then glassed it up and pulled it off. It was quick and easy. Got the right shape right away. Snaded down the glass and theres almost no need for Bondo, just a little for pin holes and thats it.

Thu Jul 26, 2007 6:52 pm

CrashedAgain wrote:
Resin applied. Didn't turn out as smooth as I hoped, but I expected it would need further finishing anyway.

Just a note on this....
Your procedure was very good but, lay up was backwards.

Had you sealed off the gelcoat side of the hole and filled it from behind with resin,mat,resin,mat ect...

The inside surface would have been as smooth as the plug you made for the hole. The under side would have the lumpy glass and resin. Then the inside could more easily be sanded , feathered and painted.

John

Sun Jul 29, 2007 8:42 am

Yes I would have got a better finish if I could have put the mold surface against the "good side" i.e. worked into a female mold rather than building up over a male plug as I did. I did it this way because improvising the male plug was a lot easier...maybe saved some time even considering the extra finishing required.

I've not had a lot of success obtaining a fully finished surface from the initial lay up so I expect to have to do a bunch of surface finish anyway (but then I don't have much experience with fiberglas either). I made new headlight bubbles for this buggy sort of like the old Austin Healey bugeyed sprite headlights. I put a lot of work into the molds, made a male pattern, took a plaster female mold off of it, sealed it with several coats of paint, coated it thoroughly with wax release but ended up with only one partial piece because the release failed to release. In the end I built up over a plaster male plug. They're in place but still need a lot of finishing. Haven't got a pic at the moment but will post one soon.

However, next f-g patch I have to do is fill the hole where there used to be a front-facing window in my raised roof van, the foil tape should be ideal for this job.

Just to be clear, it's OK to apply the f-g against the sticky side of the tape, right? I can just tape the area closed from the outside then apply the f-g from the back side?

Thanks

Sun Jul 29, 2007 8:59 am

Found a pic of the headlights:

Here's what the original was like. I think the intent was to used rectangular headlights & cover with a plexi cover. (This is not my buggy so I have blurred the plate number).

Sun Jul 29, 2007 1:12 pm

You can apply it on either side. You can tape up a piece of Masonite or Cardboard and attach it to the outside and Glass the inside. Pop off the the taped form and you should have a fairly straight piece of glass with minor sanding and finnishing to do.

247vws, Nice gun and shop it yours, what kinda Chopper you runnin ?
I run a Venus Magnum but I don't own it. It's a nice Gun but doesn't look as new as yours.
The strands look really long, gotta change the blades. :lol: I actually like it when it does that sometimes. If I gotta big Vertical job coming up I don't change the blades as it seems to get better hang if the chops long.

Sat Sep 08, 2007 8:55 pm

Any way to have those pictures posted again?

Sat Sep 08, 2007 9:45 pm

It looks like mypicshare only holds the images for about a month. I'm having problems uploading to photobucket, will try to find another image host.

Sat Sep 08, 2007 10:08 pm

That would be great CrashedAgain

Sun Sep 09, 2007 8:12 am

Reposted the pictures using photobucket.

(off topic): The posting problem to photobucket was that I have a Linux system & use Konqueror as my regular browser. Photobucket has recently updated something & konqueror has not yet been updated to be compatible. Was able to upload using Firefox though.

(on topic): Since my last post on this thread, I have used both foil tape and household aluminum foil as mold facing. Both work excellent.

I have also found that a solvent (varsol) wash seems to remove that wax layer.

Sun Sep 09, 2007 8:25 am

Thanks a bunch CrashedAgain!