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I’ve only ever French polished guitars, and I’m not set up for spray finishing. I want to experiment with Enduro Var, so without spray equipment, I will be brushing it on my test panels. If you have any hints on how to effectively brush Enduro Var, I am sure I would benefit from your experience. For instance, does Enduro Extender help the finish go on more smoothly? If so, how much should I add? Would distilled water be better than, or the same as, Enduro Extender? Thanks for any tips.

Here's a summary of what seems to work for Enduro-Var (EV from here on out!) brushed application in this shop:

- Apply EV over raw, freshly sanded and cleaned wood, or over System 3 SilverTip epoxy fill prepped with P320 and maroon 3M ScotchBrite nonwoven abrasive pad

- Apply unthinned, filtered EV with a Poly-Foam brand brush, avoiding excessive rework...apply a wet coat, quickly tip off only when needed, and allow to self-level. No other foam or bristle brush seems to work nearly as well, or be cheap enough to warrant a new brush every few coats.

- Runs or drips may be removed with the tape method (low-tack tape works best here) once they skin over and the surrounding surface is touch-safe. The wet finish exposed with skin removal should be allowed to flash off before application of the next coat

- Apply each coat within an hour of the last, or allow to cure overnight and sand with P320 to level and tooth the surface

- Flat surfaces such as tops and backs are best done level, then allowed to flash off before moving on to the sides

- We've found that brush application builds thickness much slower than spray application, so 7-8 coats seem needed for a final finish thickness of 4 mil

- We do a round or two of drop-fills as the final coat; avoid too heavy an application

- Once the finish is applied, allow to cure for 21 days before dry-sanding with P400 and P800 wet/dry and buffing with medium and fine Menzerna

- Minor sand-throughs (be careful of edges - an extra coat or two during finishing will likely not go unappreciated come time to sand) may be touched up with GluBoost thin or medium Fill'N'Finish CA without witness lines

Finally - no matter how horrible the applied finish looks (we tend to apply coats at 90 degrees to the previous, so leave a 'Scotch-plaided' surface), the finish will level and buff nicely after full cure.

Mr. John Greven has recently semi-retired from building, but brushed EV as his standard finish for the last few years of what was 50-70 guitars per year production (all done in-house without assistance!)...you might drop him a note and ask if he has some tips and tricks related to EV brushed application.

_________________
For the times they are a changin'

- Bob Dylan

Hi Woody,

Could you elaborate on this? You lost em with "The wet finish exposed with skin removal..."

Thanks

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

First: Woodie, this is extremely helpful! Thanks for the guidance.

I’m the opposite of Kevin; I understand the exposure of slightly wet finish by cutting off a pimple of finish. But I am not familiar with the shorthand reference to the tape method. Could you say more about the technique, or add a link?

Again, thanks!

I apologize for the poorly worded reference to what is referred to in this thread as the Tape Method...not to be confused with the OTHER Tape Method for joining plates...oh, goodness!

With a run or drip in EnduroVar, the surrounding area will tack up nicely, and the run/drip will skin over. Rather than wait for the finish to harden enough to allow the defect to be scraped level in prep for the next coat (taking a few days to a week or more), a strip of masking tape may be used to peel off just the skinned-over area, exposing the previous layer of curing finish and some liquid finish...that finish will level and dry, leaving a slightly rougher area that will take additional coats of finish without issue. Any evidence of a run or drip will be sanded level as part of the finishing process.

We use 3M Delicate Surface tape for this work, but I suspect nearly any medium or low-tack tape may be used. Wrap the tape sticky-side out on the tips of 2-3 fingers and use a gentle rolling motion with the fingers to lift and stretch skinned finish, allowing removal. Try this on a sample coupon (a piece of stock prepared and finished as the instrument will be) before using it on a project - there is some technique involved in taking off just the area of finish desired, but the consequences of messing things up are just a little more finish work after the finish dries enough to allow the damage to be scraped and sanded back.

Note that the longer the finish dries, the thicker and stronger the skin over the drip or run will be, and the tougher it will be to selectively remove just the skin over the defect. It is ALWAYS an option to just let the coat dry enough to scrape or file away the defect without risking any other damage. Much like lacquer, a run or drip will end up smaller in size and thinner once cured than when wet, although the higher solids ratio of waterbased finishes mean that they will still be more evident than with standard instrument lacquers.

_________________
For the times they are a changin'

- Bob Dylan

The "tape" method I was taught and use is to remove the "run" as soon as it appears and the finish is still wet. Holding the ends of the tape in your hands lay the "middle section" gently on the run and then "peal" it off to remove the excess finish ("run"). The remaining finish will "flow out" some (rarely perfectly) and dry along with the rest of the coat. It allows you to sand the area that had the run at the same time as the rest of the coat. I just use the cheap masking tape I buy for doing all the other stuff.

Perhaps a difference in finish behavior, but by the time a run in EnduroVar is evident, the finish has flowed and a run or drip forms, it seems as though the finish has begun to skin, so attaches well to the tape.

_________________
For the times they are a changin'

- Bob Dylan

Here's a small tip worth trying. Apply cold, refrigerated Enduro-Var to extend working time and increase self leveling. The thin coats quickly reach room temp so the drying time is not greatly increased but the added working time can be nice with a WB finish like EV.

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Thank You and Best To All

FWIW , I like to apply it (enduro var) with a nice set of brushes from hobby lobby, that are made of taklon for artistic water based materials ,I found it easier to brush than spray my ukes . By the time I spend, spraying cleaning and setting up the gun , I have brushed 2 or3 ukes. . In warm weather . I like to add water to slow down the drying process.

I was just in Woodie's shop (Woodie was not there that day) and handled a guitar that was done with this schedule - just fantastic. An additional tip from the shop proprietor was to NOT wet sand the EV as it will leave witness lines - never would have made the connection.

The only problem I have is that I have no power buffing, so have to run through the grits (screens?) by hand. Next time I will try EV.

Ed