Use of drywall screws

[Jack Kretmar]

This question may have been asked before. Recently I had the opportunity to visit (and possibly supply a set of helping hands to) a builder who was assembling the tub. He had fabricated the sides and had done a great job. He used dabs of epoxy to hold the foam to the fiberboard and (as usually happens) took a number of chunks out of the foam when he popped the sides. My question is, when you use the drywall screws method, how do you reach under the jig fastened to the table to insert the screws? I beleive Wayne Hicks can best answer this but a reply from anyone would be great.

Thanks, Jack

[Wayne Hicks]

Instead of nailing/screwing the jig fiixtures to my workbench, I built two "jig boxes". They allowed me to slide them on and off the workbench. I drilled holes into the masonite in a checkerboard fashion prior to nailing the masonite to the jigs. Since I could move the jig boxes, it was EZ to position the jib boxes so that I could reach the underside of the masonite, then install the small drywall screws from the bottom side of the masonite to hold the foam in place.

 

The locations for the jig boxes were marked onto the workbench so that I could always reposition them and screw/clamp them in place as shown on the plans.

 

If I had to do this again, I'd do it the very same way. I had ZERO holes/gouges that required filling.

 

I have more explained on my Chapter 5 page.

 

================================

Wayne Hicks

Cozy IV Plans #678, Chapter 23 Engine and Cowls

http://www.maddyhome.com/canardpages/pages/waynehicks/index.html

[Jack Kretmar]

Wayne,

Thanks for the explanation.

Jack

[rmaddy]

Not to discourage the use of drywall screws or other ideas but I thought I would throw this out as another data point.

 

I did the plans method exactly. I just made sure my blobs of 5-minute epoxy were very small and you only need a few in key areas to hold the foam in place.

 

When done, I only had two "dings" that needed patching. The other small ones were small enough to fill with dry micro just prior to glassing the sides. This patching added about 20 minutes to the build process.

 

Certainly if you use too many blobs of 5-minute, and blobs that are too large, you will have a big mess to patch later.

 

Wayne has some great ideas but making extra jigs in this case just seems to add extra time.

 

Of course I've used some of his other ideas when I felt they made sense for me at the time. I have also found a few other ways to do things in the plans as well.

 

I wouldn't create too many extra jigs unless you plan on making more than one plane. For one plane you may spend more time than you gain later on.

 

Enjoy

[Jack Kretmar]

Thanks for your point of view too, Rick

Jack

[David Pierce]

Has anyone tried using double sided tape to hold the foam in place? Just thought that it might not take hunks out of the foam like 5 min epoxy.

[Jerry Schneider]

Dave,

 

Yes. The double sided tape used to hold golf club grips seems to work best.