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View Full Version : Shellac or not to shellac before EM6000



Bill Borchers
07-11-2010, 11:13 PM
I have two projects. One is a table I stained with Minwax stain and the other is a blanket chest I dyed with transtint dyes (alcohol mix). My question is this: Do I need to shellac either one of these before I spray on my EM6000?
Thanks for help!
Regards,
Bill

Prashun Patel
07-12-2010, 9:05 AM
If it were me, I'd spray a shellac coat on the minwax piece:

Regular Minwax stain is oil based, so it unless it's been dried for a good long time, you could *possibly* have adhesion probs with a waterbased topcoat.

While the dye on the other piece is susceptible to lifting - and has no binder in it - any thinned, sprayed topcoat will make a fine enough sealer. If you are concerned with grain raising, you might do thinned shellac first, then lightly sand, then your topcoats.

If it's not too much work, I like using shellac in most built-up finishing schedules because it's cheap insurance, and conserves the topcoat for the build coats.

Quinn McCarthy
07-12-2010, 9:49 AM
I have used shellac over minwax stain a few times and it works good. I used Fuhr WB finish for the top[ coat. Make sure the shellac is dewaxed if you use WB finish bver it.

Hope that helps.

Quinn

Jim Becker
07-12-2010, 9:56 AM
Personally, I would use de-waxed shellac in both cases, but especially the first one over the Minwax stain. For the alcohol soluble dye, it's critical that the shellac be sprayed if you choose to use it as a sealer. Otherwise, the alcohol in the shellac will move the dye around... ;) I tend to use water soluble dyes rather than alcohol soluble dyes and seal with de-waxed shellac. Just my personal preference.

Howard Acheson
07-12-2010, 12:56 PM
I would contack the finish manufacturer. I seem to recall that the Target product sprayed over shellac can be problematic.

Rob Cunningham
07-12-2010, 7:12 PM
I would contack the finish manufacturer. I seem to recall that the Target product sprayed over shellac can be problematic.

The problem is a chemical reaction between Zinseers SealCoat and EM6000. If the SealCoat is applied too thick, it can craze under EM6000. Dewaxed shellac mixed from flakes seems to works fine.

Prashun Patel
07-12-2010, 10:14 PM
The problem is a chemical reaction between Zinseers SealCoat and EM6000. If the SealCoat is applied too thick, it can craze under EM6000. Dewaxed shellac mixed from flakes seems to works fine.

Aha. That happened to me on a walnut coffee table I made last year. The crazing was only very slight. I assumed I didn't allow the Sealcoat to dry enough before applying my Target USL (which I think is the old name of EM6000).

Bill Borchers
07-13-2010, 10:35 PM
Thanks for the input. I'll spray on some shellac (from flakes).
Jim, I did try to brush on some shellac. It kind of muddied the dye. I guess I should have figured that out.....alcohol based dye, then alcohol based shellac! BTW, what pound cut do you guys usually spray?
Thx,
Bill

Prashun Patel
07-14-2010, 8:49 AM
I go for around 1.5#. But to be honest, lately, I'm not scientific about it. Anywhere between 1:8 and 2:8 works for me for both padding and spraying.

Jim Becker
07-15-2010, 9:04 AM
I would contack the finish manufacturer. I seem to recall that the Target product sprayed over shellac can be problematic.

I have never had a problem with this. My understanding is that there have been issues with shellac "over applied" under EM6000 and it's predecessors. In other words, the shellac was on way too thick and therefore, wasn't stable.

Bill Borchers
07-26-2010, 11:09 AM
Hey guys,
I sprayed shellac and my em6000. Wow, that em6000 stuff went on really easy. It was my first time using my Earlex 5000 and I am very pleased with the results. I did one coat of shellac and then a week later I did two coat of gloss and one coat of satin em6000. My last question is finishing the finish. I do not want to make it glossy, just smooth to the touch. Thanks for great support. I would be in bad shape without you guys! So, any suggestions on the last step?
Thx,
Bill

Prashun Patel
07-26-2010, 11:20 AM
There are many ways to rub out the finish.

You'll have to wait until the finish cures completely and is at its hardest state. That can take a month for many varnishes; I'm not sure about water based, though...

After that you have multiple options:

- 4x0 Steel wool and paste wax
- 600 grit wet/dry sandpaper

You can use pumice and rottenstone, but it's messier than the above.

Whatever method you choose, use a cork faced block of wood as a backer or a dry erase/chalkboard eraser as a backer. You want to level the finish; you don't; want to dig in.

There's one more option: A ROS with a white nonabrasive pad. Apply paste wax to the surface of your piece, then begin buffing it off with the ROS.

Brad Wood
07-28-2010, 2:00 PM
I have never had a problem with this. My understanding is that there have been issues with shellac "over applied" under EM6000 and it's predecessors. In other words, the shellac was on way too thick and therefore, wasn't stable.

funny, I was just on the Target forums yesterday reading up on why my EM6000 crazed or crackled.

I took away two bits of information from the posts I read over there

1. there could be some compatibility issues with the Zinnser shellac products
2. shellac, regardless of where it came from, when applied too thick will cause problems.

I used Zinnsers seal coat. On the bottom of the piece the application was thinner than the top. I crazed on the top and not the bottom. So, it appears that while I used Zinnsers, my real problem was likely that I just went to thick with the shellac itself.

I'm just figuring out the gun I've got, so my consistency when it comes to thicknesses and such, is a bit off still.

I'm in the process right now of starting over, which isn't fun

Bill Borchers
08-14-2010, 12:27 PM
Hey guys,
I completed my two projects. For the table I finished the finish with 0000 steel wool and some Behlens wool-lube, followed by some Johnson's paste wax. The paste wax brought some sheen back to it and made it almost a glossy finish, but my daughter loves it, so all is good. For the blanket chest I skipped the paste wax step and it kept the project with a nice satin finish. I am amazed the project turned out so well for a first time sprayer. The shellac and EM6000 routine are going to be my "go to" finish routine. Thanks for all the help!
Bill