Hi to all. Been a FHB subsciber for years but just joined the forum. I am in the process of building a custom walnut hand rail for a spiral staircase in my house. It will be six 1/4″ x 1 7/8 x 20′ laminations. I haven’t selected a glue for this project yet. I need something with a fairly long working time, say 15-20 minutes or more so my friends and I can coax the glued up bundle into the clamping fixtures on the stairs before it sets up. Any opinions or recommendations from anyone? I have attached a photo of one flight with the temporary treads and rails
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First of all, reduce the size of your photos before posting. Your file size is about ten times bigger than it should be.
Use a laminating adhesive, one of the ones that is a liquid mixed with a powdered catalyst. I get mine from Highland Hardware, the big Atlanta mailorder house. Go to their website and have a look.
Bent laminations in furniture making-- my line of work-- are most often put together with non creeping glues. PVA type glues are renowned creepers and seldom selected for this application for this reason-- laminations under tension and compression and assembled with PVA tpye glues tend to straighten out over time, or slip out of alignment unless restrained in some manner.
Typical glues readily available to non-specialists used for laminated work are urea formaldehyde, resorcinal (sp?) types, epoxy resins, polyuerathane, and hide glue. Each glue has its idiosyncracies and require particular attention and tricks at assembly time. In your case you are looking for a long open time to give you the chance to fiddle.
Assuming your handrail is to be used in an interior location, i.e., not getting wet outside, probably the easiest off-the-shelf glue would be cold liquid hide glue which gives you the long open time-- about 15-- 20 mins at ~ 70°F, and is easily cleaned off with scraping and sanding after the laminations are dry. If the rail is to be dyed or stained and polished after glue up, this glue type causes the least problems under dyes, etc., if carelessly cleaned off after the laminate assembly. If you choose this type of glue, look carefully at the use by date stamped on the bottle prior to buying--- it's not a suggested use by date, it is a use by date.
Polyurethane glues would be another readily available contender requiring no mixing, but the problem with this stuff is that it foams as it dries forcing joints apart unless firmly and evenly cramped up.
There are stair makers that drop in here that do what you are aiming to do as a one off every day for a living. I've seen some pretty imressive work of theirs pictured here, and they may well have different suggestions to mine if they spot your question and respond. Slainte.
Website The poster formerly known as Sgian Dubh
Thanks for the suggestions, guys, and sorry about the big photo file... wasn't thinking.
I use urea-formaldehyde for bent laminations in furniture. It doesn't creep, is wood-colored (unlike resorcinal), is less expensive than epoxy, can be stored (unmixed) for a long time, and has a nice long working time. http://www.vacupress.com/ is a good source for it.