Sign in to follow this  
Guest

Varnishing & Dust Particles...

Recommended Posts

The trick is to keep a fairly uniform, highly filtered air flow blowing out across the work area. The air speed doesn't have to be too much, just faster than the dust particles can swim upstream. The key is to prevent any swirling air movement that can give dust a free ride the wrong way.

Share this post


Link to post
Share on other sites

Darren...my shop is pretty dry this time of year...around 35-40% humidity...

Thanks for the visual...I never considered static electricity and I'm sure now that is probably the main problem...appreciate it!

-Ernie

Happy to contribute, hope it helps. I was rubbing out a viola a few winters go and could feel the static on my arm hairs. I think it was an amber varnish.

Over thinning a stiff varnish could be a factor as well, have you tried varnishing stiff varnish with a stiffer brush? To get a heavier coat.

A theory goes that if the varnish film is thicker than the dust particle, you won't have any visible dust in the coat. As long as the surface tension of the coating isn't working against you. This comes from my days as an automotive finisher.

Share this post


Link to post
Share on other sites

My workshop is far from being clean, and I don't have a clean room. I try to get rid of the dust with a stiff brush, I work with it in

places that can hide dust such as the scroll, pegbox, under the fingerboard and in the edge/rib area. These areas

atract dust and it will be carried by the brush to other parts of the instrument when you varnish it.

I varnish outdoors. When I finish it I take the instrument to the UV box that is inside my dusty shop.

The varnish research in Dortmond found lots of dust on old Cremonese varnishes.

Share this post


Link to post
Share on other sites

I'm with Luis on this, I don't do anything super special before varnishing. I've varnished probably 100 instruments, maybe half spirit and half oil. Spirit is way easier, it dries so quick, dust doesn't have a chance to get on it. With oil I use a 2 inch paint brush and brush the violin really well before I put any varnish on it. I brush the whole violin and then brush the scroll again. Then varnish it. I do the same with each part ribs, back and top. I don't get much dust with this method. Once varnished get it in a drying box of some kind right away. It will catch any dust particles in the air. There is going to be some dust particles get on your wet varnish, there's nothing you can do about it.

I've used the same brushes for years. I clean them with solvent and then wash them with soap and water. I always comb the hair with a tooth brush and comb while cleaning. Before use I hold it up to the light and flick the hair with my finger to remove dried un rinsed soap and dust.

You can make yourself crazy trying to create a dust free environment.

Berl

Share this post


Link to post
Share on other sites

Wasn't there a letter from Strad where he had a delay in delivery because he had the fiddle hanging out in the sun to dry? I wonder how he got the dust out of all that air.

Share this post


Link to post
Share on other sites

I found that my problem was letting dust build up with each coat. I now rub out any dust before adding the next coat.

I have a double set of micron level dust filters on my UV cabinet. A small muffin fan draws in air through the filters and keeps the cabinet in positive pressure. Any residual dust is mopped up with rubbing out.

I love Don Noon's varnishing booth. B)

Stay Tuned.

Mike

Share this post


Link to post
Share on other sites

I don't think it gets any worse...like I said because I'm wearing my magnifiers...I can tell it gets worse as I progress...the more padding or stippling using whatever...brushes, foam or fingers the dust seems to magically appear...I really think it is not clean enough when I start due to rubbing and burnishing with cloths...

what were you thinking Joe and can you suggest your method of cleaning prior to varnishing

Ernie,

Cleaning prior to varnishing....beyond the common sense procedures....make sure nothing is left inside the instrument.

I like "brooming"...using a brush made from an end of a bow-hair bundle to whisk off the surface, followed by a cloth dampened with turpentine.

I find, in my very dusty shop, that most all of the junk in the varnish comes from application not drying. I just get rid of it between coats.

on we go,

Joe

Share this post


Link to post
Share on other sites

The varnish research in Dortmond found lots of dust on old Cremonese varnishes.

I started making violins long before the the advent of the internet, before the idea of hermetically sealed drying chambers, and NASA style clean rooms were needed for varnishing...

I usually varnish outdoors also - and occasionally varnish indoors, and then I bring the violin outdoors to dry. Since I have a little cast iron table that spends the day sitting directly in the dappled sunlight (in the spring and summer) - the violin usually sits and dries on that table and twists in the (normally slight) breeze.

There's never been so much dust (or tiny insects) that either will show, after rubbing out the final coat.

note; I will retrieve the violin back inside, in in the event of a dust storm, (which we do get here) or if the wind starts blowing very hard... (which it occasionally does here)

Share this post


Link to post
Share on other sites

OK I get it now...where exactly do you have your vent located?

The whole front is the "vent"... it comes out the 18" x 30" filter. I did have to partially cover some areas of the filter (on the inside) to get the flow to be more uniform.

One other benefit of this flow bench is that it is now a "well ventilated area", and you don't have to breathe concentrated turp fumes. It does build up in the room after a while, but far less than you'd get hovering over the fiddle in still air.

Share this post


Link to post
Share on other sites

Sorry, I prefer the unauthentic, crudless look. :)

Aha - an Impurist.

Ps - nice cabinet for forensic work - it would seem to be better than what some States use given recent rebuttals.

Share this post


Link to post
Share on other sites

I forgot to mention that I made a huge improvement over dust by storing my brushes handle down in a 1/2 gal. pickle jar. (Kosher dills are my favorite.) I keep the lid sealed and the brushes stay clean. ;)

Stay Tuned.

Mike

Share this post


Link to post
Share on other sites

The entire back is the filter! I see it now...at first it looked like a window frame with frosted glass...can you show the duct work from the blower to the filter?

No "duct work"... it's just a 6" deep box made of 1/4" plywood. The blower just blows into the box from the side.

Share this post


Link to post
Share on other sites

I have an electrostatic air filter beside the furnace and a portable air cleaner in the varnishing room. I don't seem to have any dust problem after giving up brush and using a cloth pad for varnishing.

Share this post


Link to post
Share on other sites

First time I've had this much dust while varnishing...I use oil not spirit...I've tried everything to eliminate dust particles...Can't figure how the dust is getting onto the instrument when varnishing...At first I thought the comercial varnish that I bought was contaminated...but I don't believe that is the case now...I first use compressed air to blow out the interior and then vacuum the exterior...after that I use a tack cloth...my brushes & sponges are cleaned and also blow dried...I've tried working in a small bathroom after vacuuming and wiping every surface...I can't believe Im still getting this much dust...I apply the varnish in very thin coats and this time I applied the varnish using only one small bush for the scroll and joints and for the rest I used just my fingers...still got dust...so what's the solution to a dust free finish...as I said I never noticed this much dust before...although I now varnish with my optivisor on...so I'm seeing alot more maybe

-Ernie

Perhaps the following from the new Ashmolean book might be of interest:

"On the 'Messie' it is obvious that the varnish has flowed smoothly on to the prepared surface and dried naturally, incorporating quite a lot of dust and natural debris in the process: there are visible clusters of dust particles gathered around the pegholes in the head and on the rib corners."

Share this post


Link to post
Share on other sites

I'm going to steer away from dust particles and into a varnishing question that has to do with color...namely the browns...lately I've seen some really nice examples of brown(ish) varnish posted...Melving, Joe Robson, Marc Genevier's...

I've looked at sources for brown varnish and Magister sells a highly pigmented dark brown paint/varnish #1708...has anyone tried this product? I'm avoiding any yellow color in my ground...and even when my wood/ground color looks nice and brown once I apply my varnish it goes orange...from there I'm unable to steer it into the brown...

...first coat over ground

I've tried coloring my varnish with combination of artist tube colors and the nano io's...the io red & green make a very transparent brown color but after 2-3 coats I get this orange color...

...second coat over ground

So how can I acheive a brown color without going to opaque?...brown color examples I like...

http://www.maestronet.com/forum/index.php?showtopic=324671&st=40

post #43

No luck finding the other photos...please post your brown colored instruments

Brown is basically a dark orange.

http://www.wikihow.com/Mix-Paint-Colors-to-Make-Brown

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.