Posts Tagged ‘ Titebond 3 ’

Success

OK, so I have got the plys to get press completely flat. What I ended up doing was applying glue to both the Horizontal and vertical leaves of veneer. Then when I clamped the MDF together I put a long 90×35 flat on the top and bottom and clamped to that.  The glue was also applied thinly.

I put a few into the shell mould last night, but that wasn’t a success. The plys were boned nice and tight, but the seams were awful. That is something that I really need to work on.

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Error

So changing the temperature of the laminating environment didn’t have an impact on the laminating process. I found that there were still some pretty big ripples in the veneer.

I think it is most likely an issue of not enough clamping pressure/not even pressure

OR

too much glue/not evenly applied. The lamination where I used less glue worked better, but there were spots that didn’t bond, which is a problem, but I will just have to make sure there is enough glue next time.

On a positive note the wax paper works great, if any glue seeps out the wax paper wont get stuck and tear, it comes off nicely.

Laminating

So while I have been making my new mould (which should be finished tomorrow if I get a chance) I have also been playing around with laminating veneer. First of I tried to laminate the plys with a very thin layer of glue. I also clamped for 20 hours and used wax paper.

There was a bit of rippling, not sure if this is due to the temperature (cold) or not clamping, or not enough glue. But the wax paper is so much better than the butter paper, No tearing etc. (the first few pics are of the process)

This morning I have laminated up two more plys. I changed some things with it, I applied a little more glue. This is because when feeling the previous lamination it felt like parts had not bonded. Well I actually used the same amount of glue, but previously I used like a small paint roller to evenly apply the glue (which resulted in a lot of waste as the roller soaked up a lot of glue). I think I may have gone overboard. Also I am going to leave it inside for most of the time to see if temperature plays a part in the process as well. The last 3 pictures are of the glue on the veneer (Titebond III) and it all clamped up.

The Big Reveal

Today I pulled the shell out of the mould. Everything went OK, could have been better and could have been a lot worse. So there was no gaps in-between any plys which is a good thing. There has been a few issues with the plys moving after the pressure has been applied, I think this is to do with the PVA glue. And the only other issue is the seams, I Need to get the each leaf of veneer measured exact; the seams looked perfect in the mould, but moved out about 2-3mm.

Some things that I have learnt from this shell:

  • PVA glue takes WAY too long to cure – 24hr isn’t enough. The time is too long, so I will switch back to Titebond III.
  • PVA glue is more prone to rippling – this could also be an issue with clamp time, not sure.
  • The shell will stick to the mould – this is pretty common sense, if the shell has glue being squeezed out at the sides, it is going to glue itself to the mould. I think this can be overcome by either coating the shell in a few coats of tung oil or similar (because that stops glue from sticking so well or using wax paper in between the shell and the veneer.
  • I need a new mould – This mould has broken, glue has become unstuck and I don’t think it’s strong enough.

Any suggestions? Feel free to contact me/leave a comment.

First shell attempt

OK so the first process in making the shell is to laminate some veneer together. For this shell I just got some cheap Radiata Pine. To increase the strength of the shell you want to cross laminate the plys. This means that every other ply will have the grain running vertical. Basically to laminate two leaves of veneer together all you do is press them in between two MDF boards. Its pretty simple. Just crank the clamps tight and leave for at least two hours.

After this we cut the laminated ply down to the correct size and dry fit it into the mould. This is to make sure it will fit nicely. I haven’t been able to make a decent seam yet. its still all gappy but each one I’m doing is getting better and better.

After the Plys have been dry fit into the mould I then went along and glued them up. The glue I’m using is called Titebond III. To provide a little bit of help gluing I inserted a gym ball into the mould and pumped it up.

Then after about 6 hours I took the shell out and that was the outcome. It was pretty bad, plys weren’t cut properly, there wasn’t enough internal pressure (need an air compressor) and some of the plys didn’t glue together.

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