Got a question here - I saw a video where a guy wrapped glued up lams with the thin type of stretch wrap on the handle/roll thingie. It had the effect of pushing the excess glue out as he we along and wrapped the whole limb. Seemed like a good idea because it would eliminate the huge glue boogers I typically get, then if you were using inner tubes on a form, you would only need to get them just tight enough to hold the limb stack to the shape of the form, having already sort of gotten the lams well clamped to each other by using the shrink wrap. At the very least it seems like it would eliminate most of the nasty gloop out that I typically get. My question though is whether wrapping the stack like that beforehand and then clamping with inner tubes would apply too much pressure and squeeze out too much glue leading to starved joints and glue lines that would fail. Thoughts?
Stretch wrap will not add much pressure. I lay plastic wrap on my form and fold it over on top of the bow before final clamping. I am sure to leave some space near the lam edges though, cause I want the squeeze out to stay there. I don't want any on the taped glass if I can help it. It makes peeling the tape very troublesome.
I use the heavy shrink wrap on a spool with the handle you mentioned. I start at the riser and wrap it each way as tight as I can without tearing the wrap and overlap each turn. This keeps the lams from slipping around and keeps glue from getting on the form or the rubber bands. Make sure you tape the glass on the belly and back before glue-up. After the bow is cured I use a side-wheel grinder to dress up the edges.
Good Idea, Thuanks for the info. Knifemaker
i use stretch wrap for all-wood-lam-bows. it tightens the stack together and adds a "starting pressure" on the lampack. i got much more better glue lines since.
Greets
Herm
Along with masking the glass prior to glue up, I also mask the sides of my riser. When the glue presses out of the laminations and drips then hardens I can scrape it off (along with the tape) with a 1" scraper. Cleans up really quickly.
Kilt......
I re-read your post. Did you really mean wrap BEFORE glue-up? I don't see how that could work
for those who say they wrap up, doesn't this interfere with the glue squeezeout? Like someone else above, I cover the form and then the layup with the plastic, but I let the glue squeeze out as much as it wants to
i would imagine that it would just make your cleanup more even. as in everything would be covered...
i used to play with fiberglass a lot for other things , and let me tell you , a vacuum bag has to get a lot of mercury moving before resin even starts to move...
think about it , the plastic isnt stronger than the clamps , so the clamps win. just means more sanding/removing what you dont want...more evenly...
Dick,
The glue does squeeze out the sides but doesn't get much on the back and belly glass. Then only have to grind the edges for clean up. Also I don't pre-shape the riser (leave it full width) and you can also grind off any glue that is on the sides.
I wrap up all my TD limbs and then put one wrap of strapping tape around the tip end to help keep the lams lined up. After you remove the limb from the form don't bother to peel the stuff off until you clean up the edges on the belt snder. Comes off easier that way.