Paulownia experience anyone?

[LowWay]

I have a couple builds in the queue with my bass builder, and he’s kept yet worked with paulownia yet.

I’m interested in lightweight builds, but want to be sure I’m not running into trouble down the road. I’m hoping to do roasted maple set necks.

I’ve read things like using dowels to reenforce screw holes. How far does this have to go? Bridge screws? Pickup mounting screws? Definitely seems like strap lock screws are necessary.

I’ll probably be doing a nice top on this. This should mitigate surface denting in the soft wood.

Any other advice from those who have used it?

 

[KidAmnesia]

If you are using a harder wood for the top, I don't think you'd need dowels for the bridge screws, but I wouldn't be agains using them anyway just to be safe. You could also bury a block of hardwood under the top instead of dowels. As for pickup/pickguard/etc. screws, letting the wood soak a couple drops of CA glue inside the hole should be more than enough.

 

[Water buffalo]

From my experience, there seems to be varying degrees/species of paulownia.

I've worked with import paulownia bodies where I found the wood to exetremely soft. I had one that I installed a strat style (through body) tremolo on, I set it up and when I went to my shop the next morning, the entire tremolo and the wooden mounting area had tore itself away from the body (I inlayed a hardwood block to remedy it). But I have found a supplier who grows paulownia here in the U.S., the wood that he offers is very lightweight but in my opinion, it isn't as soft.

I believe he also supplies several builders as well. Unfortuneatly, he may have been affected by the hurricane and the resulting flooding in the Eastern United States. I have not been in contact with him since before that time.

 

[Beej]

Paulownia is light, but I would agree that when building with it, I'd probably do some things to ensure good strength in mounting points, and would physically handle the final instrument more like an acoustic guitar than a P-bass. (ie cautious about dents, dings, scratches, etc.

Whenever I'm evaluating woods that I don't already have direct experience with, or just want to extrapolate how I think it will perform in service, I check the Wood Database, and then compare what I'm interested in with species I'm already familiar with:

Paulownia | The Wood Database (Hardwood)

www.wood-database.com

Yellow poplar | The Wood Database (Hardwood)

www.wood-database.com

Basswood | The Wood Database (Hardwood)

www.wood-database.com

Red Alder | The Wood Database (Hardwood)

www.wood-database.com

White Ash | The Wood Database (Hardwood) ("swamp ash", a marketing term, refers to ash that is grown in marshy areas that can be up to 25% lighter than typical white ash)

The figures I'm interested in are weight, hardness, elasticity (stiffness), crushing strength and shrinkage. You can see in these comparisons, Paulownia is quite a bit lighter and less hard than the other species commonly used. Personally, I'd be embedding a bridge block and using a variation of "Bruce Bars" in the neck joint if doing a bolt on.

All that said, if this is another Bordwell, I suspect you're already in very good hands.

 

[LowWay]

This is another Bordwell (actually 2) but he’s never built with the Paulownia so I thought I’d help by doing a little legwork first.

 

[Beej]

There are so many ways to accomplish the same goals in lutherie. One thing that I do in most of my builds is to use an epoxy sealcoat to provide a mildly-reinforced substrate for the finish, and I'd do the same with a softer wood like Paulownia. I've done this to an obeche body, and as far as I know it's held up pretty well (no complaints at least).

 

[funkinbottom]

I have three builds I have used paulownia. No issues with screws so far. As others have posted, dowels just to be safe doesn't hurt. I also used a couple coats of West Systems epoxy as an undercoat. It sands easily and accepts paint well. Once cured very hard. Oh, all are 5 strings and average weight is a little over 7 lbs.

 

[LowWay]

So no concerns regarding gluing in a set neck in the Bordwell style?

 

[Beej]

Likely no concerns from an end user perspective, aside from the relative softness, which can be easier to dent. As a builder, you have to be careful when working and sanding glued woods that perform in dissimilar ways, but I'm sure he's more than capable of dealing with that situation. I would also consider the weight in my design to try to get a good balancing instrument, but again he's experienced. Good on you for this though, you sound like a great customer.

 

[Means2nEnd]

I finished a tele body for another builder in my area. They do Tru-oil "hand-applied" finishes and wanted a clear coat. Although a nice flame maple cap on top it was difficult to have around and move it without surface dents and dings until we sprayed 3 heavy coats of 2K polyester sealer filler to give it some protection. Not a wood on my radar to use for us unless incased by something else. Gives you some good swell it back with a wet rag and a soldering iron game though.

 

[LowWay]

I’d be definitely putting a maple top on mine. Cliff does use tru-oil hand rubbed finishes though. Sounds like I’d want a hardwood back too.

At that point how much weight am I saving? May be easier to chase down some light swamp ash.

 

[KidAmnesia]

I’d be definitely putting a maple top on mine. Cliff does use tru-oil hand rubbed finishes though. Sounds like I’d want a hardwood back too.

At that point how much weight am I saving? May be easier to chase down some light swamp ash.

If you are worried about dents and scratches in the finished instrument, maybe a chambered body made from a harder wood is a good option. You can get it to roughly the same weight as a solid paulownia body without the instant relic concerns.