It is very possible to go on with epoxy finally as I measure gap (beam against straight edge ) nearly 0,25mm and shimming seams to be very difficult for me.

As i had told here in Greece they import 105 west system epoxy but they don’t import 209 hardener but only 206. So i will make some experiment with other epoxies much more cheaper ( 25 euros / 1,2 kgr). Ebay supplier asks 90pounds for 1.2 kgr 105-209 system.


The problem is that the temperature in my work place is now 16-17 celsious and it is dropping more as Decemper comes. So if i want to apply the epoxy method i will have to make a place with controlled heating system in order to keep the temperature as low as 20-21 celsious.
Second solution will be to go on with shimming and third ( the most expensive ) to ask a friend of mine ( that builds woodcutting machines) to use one of his machines and mill my top beams in order to come in the same plane ( but this will cost).


I want to ask
#1 ( very important to know what I am trying for )
When you measure the flatness of a beam ( or epoxy surface) against a straight edge, what is the acceptable tolerance-gap ( so we assume the surface is straight) . I use light to understand whether my top beams attach the straight edge. The touching points can be easily seen. But at other points althought i can see that there is no touch ( light passes through) , the 0,02mm Gap Filler cant pass through the gap. So what is the critical gap ? the light passing test ( that is less than 0,02mm ) or the 0,02mm gap filler test?

#2
When someone use the solution with the adjustable top beams ( without epoxy) or the shimming method how does he succeed to have the top rails in the same plane. How does he know when the two rails ( left and right ) are in the same plane? Is the thread method accurate ( the method that with the use of two threads you create the diagonals of the top rails like X. If the diagonals are in touch at the centre that means that the rails are in the same plane.

#3
When we use the epoxy method we first drill then tap then close the holes and then apply epoxy or we apply epoxy then drill and tap?

#3
What is the right angle to hold a single beveled straight edge? 90 degrees?45? something else?


Thanks for your time
Vagelis