Gluing Birch planking to plywood frames

[Diver]

Hello everyone.  I am in the process of trying to plank the up dated Sanson tug.  The planking strips are birch and the frames are ply.  The frames are properly fared with no char but I am having no success using CA.  I took 2 short pieces of the planking, glued them together with CA.  After sitting for 1/2 hour they popped apart with very little effort. I tried to moisten the plank but still no luck.  The planks seem to adhere in some areas but not others.  Any advice accepted.

[Jaager]

Wrong glue.

PVA  - yellow carpenters glue  Titebond II if a display model  Titebond III if it is RC

 

No glue is going to bond all that well to end grain. 

Scrap wood - tongue depressors or Birch coffee stirs can be scabbed on both faces of the plywood molds where the planking bonds to widen and have better grain.

Edited February 24 by Jaager

[Gregory]

1 hour ago, Diver said:

I took 2 short pieces of the planking, glued them together with CA. 

Do you have a picture?  Trying to understand what you mean by gluing the planking together.  Are you saying gluing the planks onto the frames?

 

What type of CA?  Medium consistency or gel should work.

[modeller_masa]

 

If the strips spring out like a spring, bend the wooden piece before attaching. With a little water and mini iron, you can bend wooden strips permanently. The instruciton video also shows the iron.

 

Unfortunately, the CA coated wood strips are wasted. Use new strips. I recommend buying iron and a fast-drying Titebond III PVA bond for woodworking.

[Dr PR]

I have used Duco cement to bond planks to end grain plywood bulkheads. It is an acetone solution of nitrocellulose. It soaks into the grain before hardening. It sets up in 20-30 seconds but forms the strongest bond after about 24 hours. It does have some odor, but no worse than cyanoacrylate.

 

I always use some type of clamp or rubber bands to hold the planks in position overnight.

[No Idea]

I agree with Jaager try using yellow carpenters glue.  It will give you far more time to place your planks and if you get it wrong IPA will undo your work.  I know that many modellers on this forum use CA extremely successfully Chuck being one example but personally I just can't get on with the stuff.  Yellow carpenters glue or aliphatic glue as its also called is very strong and grabs within minutes

[ERS Rich]

My two cents….have found CA on bullkheads does not immediately set, and have to do a second application after the first sort of dries, the first application is probably filling in the end grain.  Also, at the bulkhead, CA will easily bond the long grain along the edge of the new plank to the edge of the previous plank.

 

My method is generous Titebond on the plank edge, CA on the bulkheads, install the plank, hold with fingers at the bulkeads, reapply CA if necessary when a plank does not hold at the bulkhead.  Then clamp the installed plank along the edge up against the previous plank.

 

Have a rag ready to deal with the squeeze out or scrape after the Titebond sets.

 

The CA provides initial hold, the Titebond provides the ultimate strength.

 

It may be helpful to watch Youtube for cabinetmakers glueing up panels to learn about glue, and dealing with squeeze out.

 

My Constitution build log may be helpful.

 

Good luck.

 

 

Edited February 24 by ERS Rich

[paul ron]

wood to wood use the yellow carpenters glue. you will have to clamp the parts together till the glue sets.

 

 

[allanyed]

2 hours ago, No Idea said:

and if you get it wrong IPA will undo your work.

As will water.   

Allan

[allanyed]

42 minutes ago, paul ron said:

wood to wood use the yellow carpenters glue. you will have to clamp the parts together till the glue sets.

Clamps are great tools when needed, but that should not be very often IF the parts are pre-fitted before gluing them together.  This includes planks if they have been tapered and pre-shaped properly.  A tapered and spiled (or pre-bent) plank will hold after about 30 seconds of finger pressure with PVA, same as with CA and will not lift from edge bending.  If it lifts and/or does not hold and springs loose it is not yet properly shaped and needs to be re-worked or replaced.  

Allan

Edited February 24 by allanyed

[No Idea]

56 minutes ago, allanyed said:

As will water.   

Allan

Hi Allan - I use water as a clean up but I have never successfully used water to unglue my work. In fact I have had to soak some parts in ipa for 24 hours for them to separate with a good contact point. Can you expand on this a bit because if I can use water to unglue joints I would be very happy to do this. 

[Diver]

Thanks everyone for looking in on my question.  I do shape my planks to the hull profile,( as per Chucks videos), but am going to complete this build with TiteBond. It will take longer clamping and waiting for the glue to set up but I think this is the best way.   I find CA very frustrating to work with.

[allanyed]

3 hours ago, No Idea said:

I have never successfully used water to unglue my work.

If the piece is already glued on the model I tape a soaking wet paper towel to the part and rehydrate it every few hours.  Takes overnight and then some at times.   Another example, but purposely gluing parts together that will need to be separated....... when I have to make very small strips of wood such as window frame pieces that are about 0.025" square at 1:64 I thickness sand a board to that thickness then cut strips with a rule and scalpel.  These are never exactly at the same thickness as the original board, but too small to take through the thickness sander one at a time.  I glue 5 or 6 pieces side by side with the hand cut edge being the wider face of the glued up strip.  I then can run through the sander without worries.  Once done I soak the assembly for an hour or so and the glue melts and the pieces come apart very easily.   Takes a little scraping of the glue afterwards but otherwise a relatively easy task.  Thicker pieces take longer but can be done.  The hard part for me is having patience.

Allan