prime before Line-X bedliner?

[Ben]

I'm almost done with my pair of jack-12s, and soon I will be having them coated with Line-X. I have seen Duratex on Carvin bass cabinets and I own a commercial bass cabinet that's coated with a Line-X type bedliner. I am aware of the pluses and minuses of both. After comparing both, I've decided to use Line-X. Yes, I am aware that it's much more expensive.

To those who have covered their cabinets in Line-X or similar bedliner, did you prime or paint first? If so, why? If not, did the texture come good?

I am asking because, there was a thread on talkbass where someone wrote that you must prime with an oil based primer before applying Line-X because it goes on hot and will release moisture from the wood and cause pinholes and bubbling. At first glance, this makes sense. But I spoke to my local Line-X shop they said they have not coated speaker cabinets specifically, but they have coated many bare wood (solid and plywood) items, and there was no pinholing or bubbling. He said he never heard of a need to prime wood before applying Line-X.

I also checked the Line-X website and priming wood is not mentioned. They have a case study about coating wood benches and for the prep, they just sanded and wiped the wood.

Could it be a location issue? I'm in Southern California where humidity is generally low. Could this only be an issue in high humidity regions?

Thanks for any advice,
Ben

[Christian]

Line X is awesome. I've spent hundreds of dollars on Duratex over the years that I wish I could have back. I'm currently in the process of having my whole rig Line Xed a piece at a time.

My local Line X guy told me to sand down my previous paint as much as possible, and fill any holes larger than 1/8 inch. Line X is sprayed at high pressure and conforms and dries to any surface it is applied to within about 7 seconds. On my first cabs I noticed small imperfections that I thought would be hidden by line X - no dice. So really take the time to bondo any surface scratches or even brad holes. Really makes a difference. Also, it really helps to have an experienced guy apply the coating. I've gone to two different dealers, and the quality of the spraying and texturing at one was vastly superior. No drips, no uneven patches. So ask around and find someone who has sprayed something besides truck beds.

I've had Line-X applied to unfinished plywood, to duratex covered speakers, and to speakers painted with automotive paint. They have all turned out fine. Apparently adhesion problems can take a a full week to develop - but all mine are months out, and all look crisp!

[Ben]

Line X is awesome. I've spent hundreds of dollars on Duratex over the years that I wish I could have back.

Yes, I agree Line-X is the way to go if you can afford it. Since I'm only going to use it on 2 small bass guitar cabinets, it's affordable. If I were a sound guy with about 10 cabinets including subs, I would probably go with Duratex.

So really take the time to bondo any surface scratches or even brad holes.

Already done.

Also, it really helps to have an experienced guy apply the coating. I've gone to two different dealers, and the quality of the spraying and texturing at one was vastly superior. No drips, no uneven patches. So ask around and find someone who has sprayed something besides truck beds.

I spoke to my local Line-X guy. He's coated wood before including plywood. But when I go there, I will check out his work.

I've had Line-X applied to unfinished plywood

Good to know, thanks.

[Ben]

Okay, I got my answer.

I took the cabinets to the Line-X shop and spoke to the guys about my concerns of not priming before coating the cabinets. They told me that the problem with coating wood is that if you put on too much Line-X at one time, it will form a barrier on the wood and the trapped moisture can cause bubbling or pinholes. The trick is to lightly spray it almost like overspray to get enough on to heat the wood, but not enough to form a smooth barrier. After a second light coat, the wood is hot enough to have released any moisture and it is okay to do a normal coat. The guys said that if you got a lot of bubbling or pinhole-ing, it is like that the person apply the coating is inexperienced or rushing.

If we count the horn mouth as a side, my 2 cabinets have total of 12 sides. Out of the 12 sides, only one 6 inch x 6 inch area on one side got some pinholes. Otherwise, the cabinets look really good. And you would really have to be looking for imperfections to notice them.

I think the bottom line is that you can have Line-x applied without priming the wood. Make sure the person applying the coating is experienced with coating bare wood. These cabinets were my DYI project, so, I didn't mind if they are not perfect.

On the other hand, a professional cabinet builder likely can't sell cosmetically imperfect cabinets--at least not at full price. So, if I were a professional cabinet builder, I would prime before applying Line-X just to reduce the chances of bubbling or pinholes.

Ben

[DJPhatman]

Wouldn't drying a finished cabinet before Line-X also work? I'm thinking that applying some "primer" coat will actually introduce more moisture into the wood surface. I would just set up a "kiln" or oven. Think dry sauna. Quite hot for a few hours. This should remove most leftover moisture. 5 48X96 sheets of plywood, 12 8' 2X4 for the framework, and screws to put it all together. Line the cabs up under the homemade "oven" and use a not thermostatic controlled heater, IOW a heater that will not shut itself off at a certain temp. Some cheap heavy blankets/comforters/tarp/whatever you can find to use to cover the open end of the wood box.

[WB]

I would just prime the boxes and be done with it.