I am looking for a suitable glue for the following application.
I have a bridge lattice girder assembly, which seems to have been done on a 3D printer (i.e. some form of semi-rigid plastic) of about 1/2" x 15". I want to glue this onto the sanded and painted edge of the 1/2" plywood that is forming the bridge deck. Normally for these materials I would consider CA, but I don't think I can get the entire assembly coated with CA before it has started to set. In addition, I want the glue to dry clear and transparent, since excess glue will be visible through the gaps in the lattice, and this seems to rule out epoxy or Gorilla.
Any suggestions?
Thanks, Paul.
Macman44I want to glue this onto the sanded and painted edge of the 1/2" plywood that is forming the bridge deck.
Are you applying the lattice to the actual edge of the plywood, or above or below the edge?
If it's going to be placed directly on the edge, I'd suggest that you first seal the painted edge using a clear finish...perhaps Dullcote, as painted wood might otherwise still be too porous, and apt to absorb too much of the ca.
Macman44...Normally for these materials I would consider CA, but I don't think I can get the entire assembly coated with CA before it has started to set...
For cementing an item that long, you can still use ca, but if you're trying to do so in a single operation, it won't likely work.
I'd suggest, instead, that you tape the lattice in place (masking tape, applied vertically and at suitable intervals, so the tape can be stuck to both the top and bottom of the plywood should keep it in place).
You can then apply the ca to the lattice between the taped points (for applying ca neatly and with decent control, I usually place a blob of it on an impervious surface - a small piece of aluminum works well - then use an older #11 blade in the X-Acto handle to dip into the blob, then transfer it to the item being glued. This can be a little time-consuming, but should be easy to keep neat. You'll need to occasionally removed the dried blob of ca from the aluminum, and from the tip of the X-Acto blade, too.Once the exposed areas of the lattice have been secured, carefully remove the masking tape, and apply ca to those areas which had been covered.
Macman44I want the glue to dry clear and transparent, since excess glue will be visible through the gaps in the lattice, and this seems to rule out epoxy or Gorilla.
There should be little or no glue showing, but I would suggest overspraying the entire edge where the lattice is, using Dullcote or a similar clear matte coating, as any visible ca would be shiny, and certainly look out-of-place.
Wayne
I would go for something like Ambroid, Weld Bond, even epoxy or contact cement. The key is that the lattice must be at right angles to the bridge deck, or at least look strongly like it is once the bridge is in place. You may need to use small blocks of scrap wood to support the free mass of the deck while the glue sets.
How fast can you work this, 15 sec. and gel CA will work depending on many factors like humidity etc.
Thanks Wayne. Lots of good suggestions there , especially in regard to preparing the edge of the plywood and dulling down the end result to eliminate shine.
I can probably use your CA method, especially since the lattice doesn't need to be glued all the way along - at each end and in the middle would probably do it: after all, the lattice girders aren't supporting the bridge, rather the other way round. And there is some flex in the lattice.
Paul.
Selector,
Do those glues you suggest dry clear and transparent? My experience with epoxy is that it turns amber, and I think many contact adhesives do too. Not seen Ambroid.
Macman44I can probably use your CA method, especially since the lattice doesn't need to be glued all the way along - at each end and in the middle would probably do it: after all, the lattice girders aren't supporting the bridge, rather the other way round. And there is some flex in the lattice.
I apologise, but I think that I misunderstood the placement of the lattice...I pictured it as being applied to the edge of the plywood, but it sounds as if it's either at the edge of the plywood atop the upper surface or attached to the lower surface. The method I suggested should work for either version, but will likely be easier than what I originally described.
No Wayne, you were right the first time - it will be applied to the 1/2" edge of the plywood, with the back face of the lattice attached to the plywood So you will see the black painted edge of the plywood through the openings in the lattice. Sorry for the confusion. The lattice will bend just enough for me to get the CA in as long as I start at one end and work along, and don't try and glue it for the whole length, just at intervals.
And your method should work just fine.
I'd second the Weldbond for this, if you can arrange jigs or clamps to hold the joint while it sets. If the lattices do not have cross-bracing use temporary wood blocks or similar spacers for alignment.