Bending With SuperSoft 2

[Todd Stock]

Had some email traffic re: bending with SuperSoft 2, so to amp the content, thought it would be good to kick another discussion. What I've seen over the last decade re: SS2:

- SuperSoft 2 (aka, SS2) works by penetrating the wood and essentially 'puffing up' the cells of the wood to prevent cell collapse...this is a lot like filling a piece of tubing with sand or shot prior to bending, and also has the benefit of effectively softening (reducing stiffness) on a temporary basis. Because the effect is dependent on absorption of the SS2, some resinous woods like the rosewoods and denser woods like the ebonies take longer to show effects.

- There is no other product on the market besides SS2 that has both the favorable effect on bending and little/no post-bend issues. Other veneer softeners lack some key ingredient, so after having tried both commercial and home-brew bending/softening solutions, I stick with SS2.

- In terms of results, SS2 reduces ripples and other bending defects in figured woods, and especially on rift-sawn and flat-sawn ring porous stock like ash and oak, while for rosewoods and other easy bending woods, SS2 has little or no benefit. For full-bodied shapes like a dread without cutaway, I'll seldom use SS2 unless the wood is highly figured and one of the known 'hard bending' woods like curly anigre. For tighter waists and for Venetian cuts, I'll treat most woods except the rosewoods and macasser ebony. I also see reduced issues while pipe-bending with SS2, although technique will always be more of an assist there than chemistry.

- In terms of technique, I spray to wet with SS2, stand vertically over a drip pan, and allow to dry...SS2 will cause extractives to run, so bending while still wet risks driving color into purflings on bindings and reduces effectiveness of the SS2 in terms of preventing bending defects. I see no real advantage to wrapping in paper and cauls to dry, as even with rift-y curly ash, there is little movement as things dry.

- The other good reason to allow the SS2 to fully dry is that any tape markers used for bending (I use them in the waist to register the side) will not stick to wet or damp sides.

- Full effect is seen at as little as 4 hours on woods like curly mahogany, but I usually wait 12 prior to bending. Because SS2 evaporates over time, I bend within 24 hours, and always dry the wood (when bending with a side bender) until fully dry (30-40 minutes at 240-250 F seems to work for most stuff) to drive any remaining SS2 components from the wood.

- Some folks have noted that SS2 + paper makes for a big mess, which is exactly why the direction to allow the SS2 to fully dry is a very good idea. (FWIW, I don't wet any wood prior to bending in the Fox bender, preferring to control the amount of moisture present by using brown butcher paper or white butcher paper on very light woods like holly, as the moisture reservoir). This works to my advantage when bending easily-stained woods like maple or holly because the solvents in the SS2 are absent from the surface, and the water added by the wet or damp paper is not enough to see any rewetting and staining. On the pipe, the usual wetting is so brief and so quickly heated to vapor that there is no more risk of staining or marking beyond what is usually seen when using the technique.

- I use a layer of foil to isolate the damp paper/wood/damp paper package from the bending slats, so can use spring steel slats that better support tight cutaways in highly figured stuff. I have also found that using an envelope versus individual sheets of paper and foil adds drying time and is more likely to show additional surface marking as the paper or foil pulls and bunches at the wrapped edges. Effective drying is especially important with SS2 and for woods like mahogany - drying to bone dry avoids spring-back over time.

- Light sanding will remove any surface marking, and staining will be minimized by allowing SS2 to dry and avoiding too much water in the bending package

In summary - let it dry before bending; do not over-wet the wood; let the bending package fully dry after the bend.

Yes - I can bend on either pipe or in bender without and get good results with difficult woods, but SS2 reduces the risk with figured woods and know hard-bending timbers, so I use it. YMMV.

[Barry Daniels]

Todd, How do you handle bindings with attached side purfling, when using SS2?

[Todd Stock]

Attach with CA, thickness, then SS2 and allow to dry works for me.

[Todd Stock]

Another email...gotta think that somewhere, there's a group discussion going on that is raising a lot of questions. Hope this helps.

- Dry SS2 will not encourage staining or extractives transfer to lighter woods or fiber purfs
- Dry SS2 is no more flammable than the wood to which it's been applied.
- Vapors from drying SS2 can irritate sensitive membranes...do not bath in or or ingest SS2. Wear nitrile gloves when handling wet wood, and either apply in a well-ventilated area (outside works for me) or wear the same organic vapor mask you should be wearing when spraying any finish or when brushing on lacquers, shellacs, or poly finishes
- Wet SS2 encourages staining and metallic reactions with steel and aluminum - best to let it dry before bending...the extra time makes the treatment more effective
- Metals in contact with wet woods will react, and the heat and hot steam involved in bending will accelerate this process, making a minor issue into a much bigger one. Whether black iron staining when using steel slats directly in contact with wet wood (use muriatic acid to remove...prime ingredient in deck brighteners/washes) or the greenish/blue staining of acacias like koa show from reacting with aluminum slats or barrier foils (usually very shallow...sands out), it is easy to avoid the problem by using a moisture reservoir other than the wood and a barrier between metal slats and wood (foil protects the slats from rust and paper protects acacias from the aluminum foil).
- Using brown paper as a moisture controller and secondary barrier (soak it for woods that need extra water; dampen and squeegee on the bench edge for mahogany and anigre that need a puff of steam and no more) and aluminum foil next to the steel slat to isolate wood from iron.
- Kona will not stain unless it is in contact with aluminum slats or foil, so use damp paper to both control
- Rosewoods like coco and brazilian will dump a lot of resins and extractives on the surface of slat...much easier to use damp butcher paper to suck up the gunk than to spend the time and solvent to clean slats. Also saves on the time spent sanding and scraping off resins from the surface of the woods, which is where most of it will go without the paper that acts as reservoir and bleeder/resin sink. Be sure to dry the wood a little longer, and at lower temp than non-resinous woods...I dry Brazilian and coco at 200 for 40-50 minutes after bending at around 260-270...the lower the bend temp on these woods, the less color change seen and less resin dumped. Remember to oven-back the tail graft and any trim that will not be bent to even up the color prior to binding.

In summary...SS2 is solvent-based, so treat it as such...wear a mask, safety glasses with eye shields, and gloves, and try not to snort or sit in large puddles of the stuff. Use paper to provide moisture control and a secondary barrier to prevent staining when using a hot blanket or light bulb bender...use foil as a primary barrier against staining, and always use paper with acacias when using foil. Most of this is covered in the bending vids I posted on YouTube a few years back...just look for 'Bending Figure Mahogany on Fox Bender'...covers paper/foil use, etc.

Time to get some highly figured maple venetian cut bindings out of the bender...no SS2 needed on narrow stuff like that, but def helps prevent ripples on rift or flat sawn stuff like the guitar-shaped octave mandolins done a few years back.

[Eric Baack]

Have you done any veneer with it? I'm planning to vacuum bag a bookmarked piece of really nice tight flame maple veneer to a bolt on LP style body. Can I make the joint straight on the veneer or does it need a slight arch to help match the guitar body contours.

[Todd Stock]

SS2 is a veneer softener/flattener...to flatten the veneer, wet, stack with paper, and weight the package. I've only done one veneered carve top, but there are some vids on YouTube by a local builder (Chris Verhoeven of MuX Guitar/Raygun Engineering) that cover the process. Center seam will have to be trimmed...not all that difficult, and the vacuum bagging is sort of fun.

https://www.youtube.com/watch?v=xuHFc3BNJYM

[Eric Baack]

yeah, that's the video I've seen. I'll have to get a clear bag so I can get the seam right. I was originally going to use some opaque plastic that I got from work

[Todd Stock]

Also note that retreating with SS2 will dramatically reduce the chance or breakage when straightening and rebending a mis-bent side. Not that it's ever happened to me, but here's what I did, er, will do:

- Treat bent side with SS2; weight side with 30-40 lbs between two paper-covered ply cauls...some woods start going cooked pasta right away and other only flatten so much
- Once side is as flat as it's going to get (1-2 days), dampen and use a good household iron to finish off...
- Retreat with SS2 and restock under cauls/weights until dry, and rebend within 24 hours

[Robert Russell]

Todd, Thank you for all this great info. I have a set of Quilted African Mahogany that I will be using on a build in the near future and have been considering using SS2 to aid in bending them so this info is exactly what I have been looking for.

For some reason I thought you were put in the Witness Protection Program... Good to see you here.

Cheers,
Bob

[Todd Stock]

Glad you are here as well, Bob - hope things are going well for you. Re: Witless Phonation Program - LOL, no...just easier to post here than answer a dozen individual notes and calls from the folks that still have questions after discussions elsewhere.

[Stephen Neal Saqui]

Bravo! I've had that stuff in the shop but haven't used it...Thank you Todd for clearing my path!

[Todd Stock]

No problem...good luck