Dear Vicha,
Please find my actions and observations re the 2.7mm defects Permian reported for order VPIMDF15/071. ( I sent different emails with the pictures. pictures are large size to see the effect)
1. Permian reported issues across the country. We travelled to Rahan Tavan factory (we visited together a few years ago for the 16mm cracking issue) only as this was the most convenient place to check and discuss with production staff.
(Later this trip coincidently while visiting Novinchoob, I saw they also used Permian's 2.7mm, but for Melamine lamination.)
2. First we checked a few packs of raw panels. We were able to compare with 2.7mm raw panels from Sumatra Prima Fibreboard (SPB) which were also at hand and for which no issues were reported.
The general issue seems roughness due to sanding. The sanding seemed to leave rougher surface and some "scratches" and grooves. (See also pictures ). The SPB panels were clearly smoother than Vanachai. (I separately checked with SPB who confirm they use 180 grit sanding )
The deficiencies were not evenly over the whole surface and seemed to get worse to the edge of the 6' side of the panel.
The factory management reported that some packs seem to be good and the others with more defects.
I verified all checkes panels were vanachai panels but could not find any batch number on the packs.
3. The downstream process used was direct print. White color only.
At the moment of inspection they were running, but with SPB mdf only. They had no finished product left with vanachai mdf as all was delivered to customers and although some complaints came in no material was returned to the factory. Somehow customers were able to use, but requested further deliveries on SPB MDF material only.
4. I requested the factory to run a small batch direct print with Vanachai mdf. We ran about 20 boards and compared result with finished panels on SPB.
There was a clear difference in roughness of the finished product caused by the raw panels. The Vanachai surface was more like orange skin. At grading station one could not detect any defects.
Later we run one other panel which looked a little worse and then some defects surfaced where paint did not stick. (See pictures ).
Although these defects again not detectable at grading station, they resulted in rejects.
5. As per assessment of the factory staff 920 sheets of 11,500 were considered to have the small defects apart from the toughness, which was on most panels. Still all panels were sent to customers and did not return although Permian might have to discount these sheets in order to get them accepted. (The factory is subcontracted by Permian and is unaware of commercial factors)
6. We have not had any earlier issues with Vanachai 2.7mm, so I believe it has been a certain batch only where sanding issues have occurred. Vanachai can check the details. I mentioned the same to the factory and suggested the issue might already be resolved at Vanachai manufacturing level. Please check and advise.
Coincidentally I watched Melamine production at Novinchoob with vanachai 2.7mm panels and no issues were reported. I believe even if there were the same defects in these raw panels, Melamine lamination looks possible without generating defects because of the Melamine impregnated paper. The direct print is quite a thin layer.
7. As we know, white 2.7mm panels are typically used as back panels in kitchen cabinets. They are no facing panels.
The rough finished panels and even (part of the) panels with defects could still be used in finished products. One would never see the rough looks in the back of a cabinet.
Clearly it is not as per the standard and if customers have a choice they would prefer smooth panels over rough panels to ensure the end product is nice and without defects.
I have not reported back in detail to Permian as I want to learn Vanachai response.
Awaiting Vanachai’s response.
Thanks and regards,
Robin