Thread: West Sytem 105/205 test

Originally Posted by mark david

I recently cobbled together a basic vacuum bag system, the heart of which is a small vacuum pump which was given to me.The only downside is It was 110v so needed a transformer.

I was concerned about having to run this old vacuum pump all night as recommended so decided to do some testing.
I made up a small lay-on veneer panel from three widths of veneer approx 700x400mm which I would veneer onto a 6mm thick piece of mdf.This was also a good test of single sided veneering to see if any what the distortion might be.

The West sytem epoxy was rollered on to the mdf panel only with no surface preparation to the mdf and the lay-on panel taped on before inserting into the vacuum bag.

I decided after only 2 1/2 hours to switch off the pump and remove the panel, the resin appeared to have gone-off sufficiently to be well enough stuck down to sand the surface with an ROS and apply a coat of wipe-on poly.

The upshot was that there was no lifting of veneer and no distortion of the panel and was more than happy with the results.Examining the panel a day later appeared to show no issues.

I doubt very much whether overnight or all day running of a vacuum system is really necessary when using 0.6mm veneers, maybe if I was making a fibreglass boat with this resin which seems to be its main use then a long pressing time may be necessary.

I would say this is quite an extreme test and if I was making an actual project would leave in the press for a bit longer.

Having recently done some bent lamination glue-ups for a circular dining table, I believe that overnight or even 24 hour vacuum or clamping is absolutely necessary when using West Systems epoxy on bent lamination glue-ups. As I found out the hard way, if you release the vacuum (or clamps) too soon, the epoxy will not have fully cured, and the veneer laminations will start to move and delaminate.

Regards,

Roy

Hi Roy, yes I would quite agree that any kind of curved or laminate work would warrant a full overnight or day application especially where several layers of laminate/veneer are being used as the layers are wanting to spring apart.

However my test was only for the purpose of flat veneering to ascertain whether a short pressing time was even viable.For curved work I would certainly be ensuring a longer time in the press.

Originally Posted by AussieRoy

Having recently done some bent lamination glue-ups for a circular dining table, I believe that overnight or even 24 hour vacuum or clamping is absolutely necessary when using West Systems epoxy on bent lamination glue-ups. As I found out the hard way, if you release the vacuum (or clamps) too soon, the epoxy will not have fully cured, and the veneer laminations will start to move and delaminate.

Regards,

Roy