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Humidity Normal, Glued Back to Rim.......
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Author:  Darryl Young [ Sun Jan 17, 2010 12:32 am ]
Post subject:  Humidity Normal, Glued Back to Rim.......

Haven't been able to glue the back to the rim as the humidity has been abnormall low here.....in the 20% range, for 3 weeks. In fact, my back and top had reverse bows in them. Finally rained this week and I set both out on the back porch for a couple of evenings and everything is back to normal.

Layed my back in the 16ft radius dish in the go bar deck. Place the rim on top of it while it was in the mold and used go bard for pressure. Finally feels like I've accomplished something, Ha! Here are a couple of pictures:

Attachment:
Back_Glueup_1.JPG

Author:  Darryl Young [ Sun Jan 17, 2010 12:39 am ]
Post subject:  Re: Humidity Normal, Glued Back to Rim.......

And another shot just for grins:

Attachment:
Back_Glueup_2.JPG

Author:  Hesh [ Sun Jan 17, 2010 8:17 am ]
Post subject:  Re: Humidity Normal, Glued Back to Rim.......

Darryl I see some very neat work there - well done!!

Author:  Darryl Young [ Sun Jan 17, 2010 9:44 am ]
Post subject:  Re: Humidity Normal, Glued Back to Rim.......

Thanks Hesh. I did smear a little fish glue in one corner of the lower bout......and you can see where I just finished wiping it up as the wood is still wet. Also, on the popcycle rim braces you see in the side shot, I used thin CA to glue them in place as I was out of medium CA and it wasn't as clean as I had hoped for. The next day I bought medium CA and used it for the same braces on the opposite side and it went real well with essentially no glue wicking out from under the braces so no stain. Live and learn. I'm trying to be as clean as I can.......but it's something takes a little experience to get right. I wish I had more go bars to use for this glue up but it was a very good fit and hopefully the fish glue will tend to pull the joint tighter.

Author:  George L [ Sun Jan 17, 2010 12:42 pm ]
Post subject:  Re: Humidity Normal, Glued Back to Rim.......

Darryl,
+1 to Hesh's comments!

I notice that you refrained from gluing the back support strips between the neck and heel blocks and their closest back braces. That's clever, as it can be a little tricky to get a clean, precise fit when removing material that's already glued in place--at least for me. :-)

I also like the way you have arranged your glue up, allowing a view into the box as you apply the clamping pressure. I've always glued the back and top plates on in the opposite manner, with the go bars pressing on the plate being glued down, not pressing against the reverse edge of the rim. Hard to describe in words, so I've included a pic. In this shot I have placed a protective caul between the go bars and the top plate:

Image

Using your method would make me nervous about breaking off the lining. It looks like yours held up just fine. I can't tell if there is a radiused dish beneath your back plate or not. If so, is that why you set it up this way? I plan to use radiused dishes from here forward, so I'm just curious. I'm also trying to teach myself to be more imaginative while I'm building.

Nice job,

Author:  Darryl Young [ Sun Jan 17, 2010 8:41 pm ]
Post subject:  Re: Humidity Normal, Glued Back to Rim.......

George,

Yes, there is a radius dish under the back plate......and that is why I glued it up this way. Sand the rim in the radius dish till it fits perfectly, lay the back in the radius dish (the same one it lay in while gluing the braces to the back), while the mold is in the rim place it on top of the back, then put a go-bar or two in the center of the back to make sure it conforms to the radius of the dish, then use go-bars around the perimeter of the rim/lining to hold the rim against the back while the glue sets. In theory this should have the glue curing with everything fitting perfectly......and in practice it worked great!

The go-bars are placing as much (or more) pressure on the rim as they are the lining so I had no fear the lining would break off. I do wish I would have had more go-bars to place around the perimeter while the glue dried. At least it had the weight of the mold to help some.

Author:  Jeff Highland [ Wed Jan 20, 2010 11:36 pm ]
Post subject:  Re: Humidity Normal, Glued Back to Rim.......

A few more go bars would'nt hurt, but gluing like that with the pressure through the rims distributes the clamping force well unlike just placing the bars on the plate.

Author:  Darryl Young [ Thu Jan 21, 2010 1:03 pm ]
Post subject:  Re: Humidity Normal, Glued Back to Rim.......

Good point Jeff.

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