Filling fiberglass holes?

[Green Jello]

I was working on some internal fillets for my Madcow Piranha and I was wondering what you guys do with the holes that are left over? It seems to me that if you did the external fillets over them, some of the epoxy would sink down into them and cause a divot in the fillet.

 

[Aksrockets]

The internal fillets should have covered up the holes. I would just cover up the holes with a little bit of filler and proceed with external fillets. Looks nice so far.

Alex

 

[hornet driver]

The internal fillets should have covered up the holes. I would just cover up the holes with a little bit of filler and proceed with external fillets. Looks nice so far.

Alex

+1 what he said---small addition---make sure what you fill them with cures 100%--The fillet material will rewet them and can cause them to shrink a tick---wanna avoid that---I'd use an epoxy paste.

 

[fyrwrxz]

I have a small set of removable holes I used as an aircraft mechanic. They are very hard to find and expensive.

 

[sodmeister]

I have a small set of removable holes I used as an aircraft mechanic. They are very hard to find and expensive.

.....:rofl:

If ever I go through a bout of clinical depression ,I`ll just read one of your replies ,should work well !

Paul T

 

[Green Jello]

Any suggestions on fiberglass filler material? Something from an auto parts store I'd imagine.

 

[cherokeej]

Epoxy mixed with Cab-o-sil, aka colloidal silica.

 

[krusty]

Any suggestions on fiberglass filler material? Something from an auto parts store I'd imagine.

When I've needed to fill holes like this, I've used a syringe to inject a blob of 5 min epoxy into the hole. Stick a little tape over the hole and turn the rocket so the epoxy pools above the hole & tape. Repeat for the other holes. Never had any problems or needs for fillers or anything.

Hope that helps!

Krusty

 

[Coop]

I've never injected fillets like that--for internal fillets, I've always left off the rear CR until the internal fillet were done, and then placed it. I'd go with thickened epoxy fillets, and in the event that some did leak down and cause a divot, go back over and spot-fill as necessary...


Later!

--Coop

 

[Coop]

I have a small set of removable holes I used as an aircraft mechanic. They are very hard to find and expensive.

Aircraft grade removable holes ARE expensive. When I was a truck mechanic, we just used oversized passenger vehicle removable holes. The difficult part about them at the time (we're talking lat 80's, early 90's) was finding a machine shop to bore them out for us.


Later!

--Coop

 

[stealth6]

If you want to save some money - instead of using those expensive removable holes, simply save the dust from when you drilled the holes in the first place. Once you've done your internal fillets, simply reverse the drilling process using the original dust. This way you also end up with no waste to clean up.

s6

 

[sodmeister]

How about just some Fix it Epoxy clay or similar and just make plugs ? Plugs harden ,sand almost flush leaving a slightly mushroomed head ,fillets and done !

What`s the confusion about :confused2: LOL

Paul t

 

[troj]

I always do external fillets, with thickened epoxy, and it fills the holes quite nicely, along the way, along with making the fillets. The key is to mix your epoxy thick enough, and it won't sag into the holes.

I use fumed silica, sometimes with a small amount of milled fiberglass. Sucks to sand, but it makes solid fillets, which are easy to shape. If you use CJ's method of doing the fillets, using tape and a piece of PVC or copper tube, or Giant Leap's method with a spoon, there's little or no sanding required.

-Kevin

 

[cwbullet]

To fill pin holes, I use icing (it is like bondo). It is very easy to sand.

Hole like above, I use epoxy clay.

 

[Fdog]

+1 on what Kevin said - my external fillets have always covered the holes nicely.

This is phenolic microballoons mixed with epoxy until like Jiffy peanut butter.

All the best, James