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s mckee
07-22-2000, 06:18 PM
Does anyone know of any reason why a person should not use 1/4" MDF panels as a support for oil painting? (Obviously, after they have been properly primed.)

It just seems to me to have a better surface than masonite. It cuts cleaner. It sands without tearing apart. Most importantly, unlike the bruised and warped masonite panels at the lumberyard, the MDF panels don't seem to have been jumped on by armies of teamsters.

Actually, I'm not sure what is the difference between masonite and MDF. Is MDF just a hardboard variation? What gives? Why is it I've never heard anyone suggest using MDF as a support?

- Stevie

sgtaylor
07-25-2000, 03:09 PM
I know of no reason not to paint on MDF - and I'm not sure why you've never heard it suggested, as I know a number of people who do or have used it. I've only used it once (I got a free sample from my brother, the carpenter) and I was very happy with the results. I don't know much about its composition - I think it is basically the same thing as masonite except that it is much denser.

s mckee
07-26-2000, 04:01 AM
Thanks for the reassurance, Sg. I'm glad to hear its in common use. For the life of me, I couldn't figure out what could possibly be wrong with it - people paint on cardboard, afterall, surely MDF is better than cardboard - but you never know with these things. As soon as you find what appears to be a perfect surface, some naysayer always crawls out to tell you a hundred reasons why you should never use it as a support. Like with the 'tempered' masonite business.

kelly
07-26-2000, 09:18 AM
Mr Mckee, what does MDF stand for? I dont believe ive seen it anywhere.

arcitect
07-26-2000, 10:25 AM
Originally posted by s mckee:
. As soon as you find what appears to be a perfect surface, some naysayer always crawls out to tell you a hundred reasons why you should never use it as a support.

Permanence is over rated. Millions of works created on shoddy materials hundreds of years ago are still around today, they just tend to have some cracks. Oddly enough, so do the works on "ideal" supports.

If you can reasonably expect a work to last 50 to 100 years, you have really done enough to keep yourself out of court. Even if it is only because you are dead! MDF should net you at least that.

The image is what counts -even if it is only fleeting.

sgtaylor
07-26-2000, 01:00 PM
Originally posted by kelly:
Mr Mckee, what does MDF stand for? I dont believe ive seen it anywhere.

I know this question wasn't directed towards me but....

Medium Density Fiberboard



[This message has been edited by sgtaylor (edited July 26, 2000).]

Painter
09-11-2000, 03:45 AM
Which is cheaper, hardboard, or mdf?

------------------
God Blesses!
Ched

bruin70
09-11-2000, 10:13 PM
if your talking about particle board,,,,you can use it....{M}

billyg
09-14-2000, 05:20 AM
Please bear with me as I quote from Pip Seymours book. MDF, Medium Density Fibreboard.Another type of exploded fibre board. The fibres are compressed to form a compact homogenous surface.It can be prepared with traditional geso,animal size and oil primer, or acrylic grounds. MDF is quite moisture resistant although the edges tend to be more absorbent.!!!. MDF can be difficult to obtain in cut sizes due to the inclusion in manufacture of urea formaldehyde resins which are thought to be carcengenous in nature.No problem to the artist, but to the supplier when cutting the board in his workshop spaces.There is a newer type using polyurethane resins. When preparing the board, do do the edges first as this helps prevent any swelling of the fibres when doing the faces.Do both sides initially to prevent any warp under 1/2 inch size before extra coats on working face.
The board can also be covered with canvas using a archival acrylic adhesive to assist in the process of stretching and tacking.Only tack the reverse side and not the edges.When completed and dry, the surface can be painted with one or two ciats of neat acrylic primer brushed into the canvas. QED.
Billyl

Mark St.-C
09-14-2000, 05:30 AM
Thanks for the info on the urea formaldehyde, Billyg. I cut my own MDF and while I normally wear a mask while using the saw, I'll make sure from now on to wear a respirator instead.

Artwayze
01-27-2008, 05:17 PM
MDF is made from reconstituted sawdust and pummeled shavings. This is mixed with glue and formaldehyde and then rolled into sheets. It is a light sand colour. It is extremely flat and stable. I use it a lot for oils, pastels and acrylics. It is possible to glue canvas or heavy watercolour paper to a panel using woodwork glue or acrylic gesso. Arches too makes a great surface for oils, if it's primed properly.

I think 1/4 inch MDF would be a little heavy though, as this material is very dense; much heavier than the same size piece of harboard (masonite). The problem increases in proportion to the size of panel on which you are going to paint. So I use 3mm board (just over 1/8 inch), which I buy in 8 foot x 4 foot sheets at my yard. Cutting is done for me, so I don't have to breathe in formaldehyde dust! At the yard I use, the cutting is free. :clap:

I always give MDF three coats of acrylic gesso followed by one or two coats of white, primer house-paint, mixed with pummice powder. This gives a good key. I also seal the back and edges of the panel, as MDF doesn't like water to soak into it.

The pummice powder in acrylic gesso is also great for pastelling. Try it. You will be surprised!
:)
Hope this helps
John

onefinepint
01-27-2008, 06:25 PM
I almost always use 1/4 inch size cut from large sheets into 5 x 7 and 8 x 10 inch sizes. I don't find it too bulky. With the edges sanded, three coats of gesso on the front, one coat of flat acrylic latex on the back, I'm ready to go. It provides a sturdy surface which I like very much.

ElizaLeahy
01-27-2008, 08:53 PM
I was gluing canvas to it myself, until I found Ampersand. But it did work well. I use to turn it over when everything was dry and use the edge of it to trim the canvas. Ended up looking like a Raymart panel (not sure of spelling of brand name) which is too expensive for me to ship over here, but is another good hardboard prepared panel.

I found I just wanted to paint, and the added time preparing panels was begining to annoy me! :)

Einion
01-28-2008, 02:36 PM
John, this thread is from 2000 in case you didn't notice; that's nearly as old as it gets here :D

MDF is made from reconstituted sawdust and pummeled shavings. This is mixed with glue and formaldehyde and then rolled into sheets.
Formaldeyde isn't added as an ingredient, it's part of the resin used as a binder - most commonly urea-formaldehyde, but others are used in higher-quality MDF.

One of the reasons to be cautious about using MDF to paint on directly, for permanent work, is the degradation of the glue over time; this is now an important issue in the US due to the large amounts of bonded-wood products in American homes, including OSB, MDF, LVL, particleboard/chipboard and plywood, most of which also use urea-formaldehyde glue.

I think 1/4 inch MDF would be a little heavy though, as this material is very dense; much heavier than the same size piece of harboard (masonite).
MDF is a medium density board, it's actually lighter than many hardboards (which are a type of HDF) for the same thickness.

...

More on the resin here (http://www.fpl.fs.fed.us/documnts/pdf1996/conne96a.pdf) and the Wikipedia entry on MDF here (http://en.wikipedia.org/wiki/Medium-density_fibreboard) for anyone that wants a quick intro to the subject.

Einion

Aires
08-23-2008, 04:04 PM
MDF, masonite, luan, plywood - there are a host of hard surface subtrates that are useful if well primed and then gessoed to the desired surface. I am not arrogant enough to worry about my paintings being preserved for hundreds of years, if they last my life time that is all I will be here to worry about, right? I don't class myself with the likes of DaVinnchi but I really wonder if he sat around worrying how long his paintings would last beond his life time. Anyway, a very good sealer coat on ALL surfaces and several coats of gesso usually makes a pretty good painting surface unless you are only satisfied with stretched canvas. Then nothing else will meet approval so no need to take that into consideration. :smug:

1100ww
08-23-2008, 05:26 PM
I've never felt totally comfortable with the idea of painting on MDF, although I do like the surface. This thread did make me think of something interesting, though:

I bought, used, a high-end record player that was manufactured about 25 years ago. I noticed the base of it is made of MDF; it's very obvious when looking at it from underneath. The bottom and insides aren't sealed or anything. The outside has a nice veneer on it. The whole thing still looks brand new, and I can't imagine why it wouldn't be around for several more decades.

When I noticed the turntable was made of MDF, I was surprised. I would've imagined a material like that relegated toward lower-end, cheap products. Turns out that there are several high-end audio companies today making expensive turntables from MDF...apparently not because it's a cheap material, but because of its acoustic properties and consistency. I wasn't expecting that. I'm still not sold on MDF, but I found this interesting.

WFMartin
08-23-2008, 06:29 PM
A year ago, or so, my wife brought home a kit composed of pre-cut, and drilled, MDF boards for building a small cabinet with drawers.

Among the instructions were directions for smearing some glue (like Elmers) on some furnished dowels, and pounding them into pre-drilled holes in the MDF.

When I did so, glue exuded from many orfices on the SURFACE of the MDF, and quite a distance away from the hole into which the glue-covered dowel was being pounded. To me, this indicated an extraordinary porous material.

I decided at that time that MDF was not the sort of material to which I was willing to trust my serious oil paintings. Later, I did learn that there are several DENSITIES of MDF, and if I were going to be even slightly tempted to use it for oil painting, I would most certainly consider one of the more dense versions. Hardboard (the old "Masonite") is MUCH denser than MDF. I've painted on hardboard with good success.

Bill

TheBaron
08-23-2008, 06:39 PM
A year ago, or so, my wife brought home a kit composed of pre-cut, and drilled, MDF boards for building a small cabinet with drawers.

Among the instructions were directions for smearing some glue (like Elmers) on some furnished dowels, and pounding them into pre-drilled holes in the MDF.

When I did so, glue exuded from many orfices on the SURFACE of the MDF, and quite a distance away from the hole into which the glue-covered dowel was being pounded. To me, this indicated an extraordinary porous material.

I decided at that time that MDF was not the sort of material to which I was willing to trust my serious oil paintings. Later, I did learn that there are several DENSITIES of MDF, and if I were going to be even slightly tempted to use it for oil painting, I would most certainly consider one of the more dense versions. Hardboard (the old "Masonite") is MUCH denser than MDF. I've painted on hardboard with good success.

Bill

Are you sure it was MDF Bill? MDF is a solid compressed fibre board,I do know if you don't drill a pilot hole for a screw it fractures the MDF to the extent is splits.

I've painted on MDF but sealed it on the sides and back with PVA and primed the painting surface with gesso.

the painting not finished but has held up ok after 8 months,great smooth surface to work on.

Problem with hardboard is it bends in warm conditions overtime.

Nilesh
08-23-2008, 06:55 PM
Does anyone know of any reason why a person should not use 1/4" MDF panels as a support for oil painting?

The next step in choosing our hardboard was to determine which species of wood to use. For example, hardboards manufactured through the dry process such as MDF boards are made from softwoods that tend to be more acidic in content. The Ampersand Hardbord™ is primarily manufactured from Aspen trees that have more uniform fibers and have more of a neutral pH than that of other woods.

There is more that might be of interest here: http://www.ampersandart.com/tips/archivalinfo.html

***
MDO might be worth a look.

Die board and magnesiacore might also be worth looking into.

WFMartin
08-23-2008, 07:52 PM
Are you sure it was MDF Bill? MDF is a solid compressed fibre board,I do know if you don't drill a pilot hole for a screw it fractures the MDF to the extent is splits.

I've painted on MDF but sealed it on the sides and back with PVA and primed the painting surface with gesso.

the painting not finished but has held up ok after 8 months,great smooth surface to work on.

Problem with hardboard is it bends in warm conditions overtime.

George,

Yes, it was most certainly MDF.

I believe that this MDF material is going to be one of those items that will inevitably receive all sorts of criticisms from users, from hating it to loving it.

The reason will be that there are simply several DENSITIES of the stuff. It may be called, "Medium" Density Fiberboard, but, according to a finish carpenter friend of mine, there are, in fact several density grades of it.

When he showed me the difference between a higher and a lower density version, I was hard-pressed (no pun intended) to tell the difference between the two by looking at them. One can only speculate what densities of this material the art stores or internet supply houses sell, as their version of "MDF". I suppose one can always hope that it will be the higher density type.

I really don't plan to use the stuff for oil paintings, although it does look mighty tempting at times. But, I believe it is a good idea for artists to realize that there simply are more than one density grade of the material, when choosing their substrate. Till then, hardboard should fill my needs very well.

Bill

Alma
08-30-2008, 05:19 AM
The problem with painting on any kind of hardboard, including MDF seems to be "outgassing" of volitile substances which has an undesired effect on pigments. This is according to the latest edition of Ralph Meyer's, Artist's Handbook. Earlier editions of this book were quite favourable toward hardboard. Apparently the test of time has rendered a less favourable verdict. All wood supports do this, but the reason old paintings on wooden panels have held up so well is that the thick coating of gesso that was applied contained enough calcium carbonate to neutralized the harmful gasses.

nit-wit
08-30-2008, 05:58 AM
I've been using an old student oil on MDF of mine as a fence in the garden to keep my dog from getting around the bins. It's 12 years old and has been out in the garden at least three, the MDF itself was 2nd hand and salvaged from the RCA art bar, when they renovated. Ginger Hen even made her nest right against it for shelter. The painting and MDF are in such good condition, despite exposure to the elements, dog and hen, that I could arguably retrieve and sell it to somebody (is a bit warped, but I could easily straighten that out). Garden not recommended as painting storage, but suggests some durability.

Andrew

nit-wit
08-30-2008, 06:27 AM
And here's Ginger Hen herself in front of said MDF painting. That's actually a screen printed spiral design on the back from its Art Bar days.

It makes me laugh anyway.

Andrew


http://i376.photobucket.com/albums/oo203/nitwitness/IMG_9721.jpg

Mark Sheeky
08-30-2008, 07:27 AM
This link (http://www.hudsonhighland.com/woodglossary.htm) has some information on the use of MDF for fine art. More density does not necessarily mean better, the density has to be low enough to allow internal expansion (otherwise the wood will warp) but high enough to be phyiscally tough. It's one reason why I think MDF is the best wood surface. Downsides include the preparation work. Sealing with any water based sealer causes the different grainy bits to stand up a little (just like water based wood dye does to the grain). As has been mentioned, a good seal is important to prevent possible contamination from anything in the wood. On the whole though I like MDF and have painted on it for a few years without any problems. Even the early totally untreated ones seem to be in tip top condition.

Mark

ElizaLeahy
08-30-2008, 08:42 AM
I'm not sure what the fuss is. I mean, how long do you think that unprepared canvas would last if you painted on it?

As stated previously, it's going to outlast our life times - and probably longer then some of the cheaper canvas's that you can buy at art supply shops.

Of course it has to be prepared correctly - doesn't everything?

Alma
09-01-2008, 05:43 PM
Thanks for the excellent link, Mark! The Hudson Highland site is truly encyclopdic in scope, giving me a good understanding of the actual mechanics of wooden art panels, so much more informative than, Ralph Myers. The solid "polymer panels" also sound like something worth trying. How sad that this company is no longer making art panels. Does anyone know why this is? I wasn't able to contact them.
Thanks Nit-Wit, for sharing your very interesting and comical first hand experience with the the durability of MDF. You have renewed my faith in this material. Got to love, Ginger Hen! :lol:

RonL
03-14-2009, 07:18 PM
This will be a topic that will persist forever (prepping rigid supports) so even though this is an older post I thought I'd add my thoughts.

First... do not purchase prefab MDF if you are likely to want your artwork to be archival. I can not imagine that manufacturers produce truly archival panels, no matter what they say, especially since in the art world and art market rigid supports (e.g. MDF, Masonite, etc.) are considered 'student' grade and will almost certainly be prepared that way.

I mention the following only for credibility sake. Though I have an MFA and have taught at a University perhaps more important is the fact that for many years I was a foreman in the Allied Trades Painters' Union. I mention this because I have experienced what can happen when numerous kinds of surfaces are not prepared properly under numerous (i.e. dry and humid) conditions.

For those who do not want to read a very long post... the short version is...

Apply two to three coats of an oil-based commercial primer-sealer on all sides (i.e. ends also) of your MDF (aka Masonite, hardboard, etc.) and then apply a couple of coats of gesso to the surface that will be painted on. (re. manufacturers of primer-sealers further down in this post)

Does it matter if you use tempered or un-tempered. No.... as long as you lightly sand and dust the surface prior to sealing it with a primer-sealer. If you thin either the oil-based or water-based formulas (to reduce brush marks or roller texture) you will then need to increase the number of coats to insure sealing of the acids in the MDF.

If you do not properly seal all sides of a panel then the gesso alone will NOT assure you that it will not discolor or become moldy over time. Even if you have professionally strained/mounted it and have used un-tempered MDF.

That's the safest short answer... now here are the specifics.

For purposes of brevity I will now refer to Masonite, hardboard, etc. as MDF.

As a painter think about this...

Would you ever consider gessoing and then painting directly on wood? Answer... Of course not. Why... because of three reasons...

1) Warping (perhaps not immediately but over the years)
2) Discoloration (again... it may take years... but eventually any acids in the wood will leach in to the applied paint)
3) Mold (gesso does not prevent mold, and MDF will absorb more moisture out of the air than canvas and linen)

Again... as a painter would you ever consider gessoing and then painting on your kitchen cabinets that have been varnished or shellaced? Answer... Of course not... why... because the gesso will not bite/adhere properly to varnish or shellac.

The solution... use a primer-sealer.

Oil-based ones lock-in the acids best, but if you apply at least two coats of a water-based primer-sealer this will also provide plenty of protection (assuming you don't live in the Bayou and leave your windows open most of the time ;)

Manufacturers of very good primer-sealers are:
Zehrung ("Z-Prime Plus")
Zinsser ("Cover-Stain," "Bulls Eye 1-2-3")

Any good hardware store or lumber yard should have the above. Though in California the oil-based formulas are limited to quart size because of OSHA.

Oil-based primer-sealers also have the advantage of being able to be sanded more smoothly. Where as water-based primer-sealers resist sanding. So especially with water-based primer-sealers never use anything coarser than a #220 sandpaper to remove obvious bumps (i.e. dust, particles of paint, etc.). And do not try to remove brush marks or roller texture at this stage.

So if you have left bold brush strokes or roller texture while using a water-based primer-sealer, and you don't want them to appear in your finished painting, you will then need to apply and sand at least two and maybe even three coats of gesso which you will be able to sand smooth with #220 sandpaper.

I suggest you only hand sand the surfaces... no not block sand them. The reason is because the block sander may thin an area of primer-sealer if it has been conforming to a slight imperfection in the MDF where as your hand will more readily conform to it. Block sanding may result in reducing the acid resistance in the thinned area. (This is being perhaps overly perfectionistic, I realize, but at least be aware of it.)

Personally I would only use rigid supports (i.e. MDF) if your style requires it (heavy textures, modeling, etc. or if you are a plein air painter since it will also allow you to transport your work more carefully than would canvas/linen).

I say this because some people think that using MDF is 'easier' than preparing canvases. It is definitely not if you want to make certain that your work is archival.

Some on these forums have suggested using shellac or varnish to size the MDF. As I have alluded to above (e.g. gessoing over kitchen cabinets)... I would definitely not suggest that because that will not afford the 'bite' for the gesso (even if the gesso is oil-based) and also... unless the dimensions of your MDF are very small... there will be unintentional flexing that will create micro-fractures over the years which will allow acids and moisture to migrate. It could be argued that if the panel is glued to a strainer that micro-fractures will not occur... never-the-less the bite will not be as good.

Again... the above is obviously only for those that want the panels to last a long time. If you are only experimenting and will toss them... none of this matters. Perfectionistic I realize... but I'm thinking in terms of archival properties.

Well... if you have made it to here, you may be as obsessive as I am :)

Realize though... without obsession... there can be no great art.

Enjoy!

Regards,

Ron

Einion
03-16-2009, 09:51 AM
Did you write this for Wikipedia Ron?

Does it matter if you use tempered or un-tempered. No.... as long as you lightly sand and dust the surface prior to sealing it with a primer-sealer. If you thin either the oil-based or water-based formulas (to reduce brush marks or roller texture) you will then need to increase the number of coats to insure sealing of the acids in the MDF.
Tempered and untempered MDF?

For purposes of brevity I will now refer to Masonite, hardboard, etc. as MDF.
But they are completely different Ron! MDF is a specific thing, as is hardboard - the difference between the two is critical; one cannot just lump them together as though they're equivalent products.

Again... as a painter would you ever consider gessoing and then painting on your kitchen cabinets that have been varnished or shellaced? Answer... Of course not... why... because the gesso will not bite/adhere properly to varnish or shellac.
Not if it's glossy, no. Because there's no chemical bond we rely on a mechanical bond (which is how 'gesso' bonds with everything, technically) and this can be achieved with sufficient micro-texture, just as you would if you were priming rigid plastics where you sand/scuff them first.

The solution... use a primer-sealer.

Oil-based ones lock-in the acids best, but if you apply at least two coats of a water-based primer-sealer this will also provide plenty of protection (assuming you don't live in the Bayou and leave your windows open most of the time ;)

Manufacturers of very good primer-sealers are:
Zehrung ("Z-Prime Plus")
Zinsser ("Cover-Stain," "Bulls Eye 1-2-3")
What are the ingredients or additives to these primers that provides their sealing properties?

I suggest you only hand sand the surfaces... no not block sand them. The reason is because the block sander may thin an area of primer-sealer if it has been conforming to a slight imperfection in the MDF where as your hand will more readily conform to it, thereby reducing the acid resistance in the thinned area. (This is being perfectionistic, I realize, but at least be aware of it.)
MDF is quite flat. It is well known that hand sanding is less efficient (much less) at evenly sanding a flat surface, that's the entire purpose of sanding blocks.

If you're referring to the texture of MDF then the sandpaper itself won't conform to the tiny variations in height, it'll just remove material from the high spots and work its way down.

This is assuming the sandpaper hasn't already clogged with acrylic 'gesso' :D

Personally I would only use rigid supports (i.e. MDF) if your style requires it (heavy textures, modeling, etc. or if you are a plein air painter since it will also allow you to transport your work more carefully than would canvas/linen).
Why? Board materials, despite individual flaws or weaknesses, have an unquestionable advantage over natural-fibre canvas due to the differences in dimensional changes, which is a critical issue with regard to oil paintings.

Incidentally, you're giving an example - MDF isn't the only rigid support. So e.g., not i.e.

Some on these forums have suggested using shellac or varnish to size the MDF. As I have alluded to above (e.g. gessoing over kitchen cabinets)... I would definitely not suggest that because that will not afford the 'bite' for the gesso (even if the gesso is oil-based)
Oil-based gesso?

...and also... unless the dimensions of your MDF are very small... there will be unintentional flexing that will create micro-fractures over the years which will allow acids and moisture to migrate. It could be argued that if the panel is glued to a strainer that micro-fractures will not occur... never-the-less the bite will not be as good.
Could you post some evidence of this please. Thanks.

Again... the above is obviously only for those that want the panels to last a long time.
The use of polyurethane is not universal but it has been chosen specifically, out of many possible products to use as a size, by a couple of high-end commercial panel manufacturers.

Einion

TheBaron
03-16-2009, 10:04 AM
And here's Ginger Hen herself in front of said MDF painting. That's actually a screen printed spiral design on the back from its Art Bar days.

It makes me laugh anyway.

Andrew


http://i376.photobucket.com/albums/oo203/nitwitness/IMG_9721.jpg

Oh wow! if you had not said it was a hen I'd of sworn it was sheeps head stuck behind all that garbage,the hens head lloks like its eye..follow that down and you'll see its ear and to the viewers left of the eye its mouth.
:eek:

rltromble
03-16-2009, 12:46 PM
I just want to say if you expose any wood product to lots of moister it could warp. But MDF is quite stable and less likely to warp when compared to some other wood products. MDF is quite heavy however and I wouldn't use it on big paintings.

RonL
03-16-2009, 06:55 PM
I have spent most of my life painting one thing or another as well as earned an MFA, worked as a scenic artist at NBC studios, and taught at La Sierra University.

I was in Dick Blick's (Blick Art Materials, Pasadena, California) one time and I asked if they had any long-handled sable brushes for oil... and even there... an employee said... "You don't use sable for oil... you use bristle." And this store is known for hiring students that attend Art Center in Pasadena, which is one of the finest art schools in the world.

There are those with answers that are correct for most circumstances (bristle brushes), but not all circumstances. That's why I jokingly said above (in my original post)... "Not if you live in the Bayou and leave your windows open most of the time." And it is the reason why I also post here on rare occasion asking questions (e.g. Oil of Spike Lavender).

For all practical purposes, what I indicated in my original post is true for any circumstance I can think of where the art will not be exposed to incredible environmental conditions.

I don't want to turn this or my original post into a 'food-fight' which I have seen happen on these forums where someone comes along and dissects each-and-every paragraph even to the extent of semantics, grammar, and minor typos. (Truly unfortunate since this website on average is excellent.)

Rationales aside... i.e. one person's 'food-fight' is another's search for specificity and truth...

I stand corrected in trying to be brief in using the acronym MDF (medium density fiberboard) to stand for all fibrous boards. This is, agreed, when accuracy lost to brevity. But... for the purposes of my post it did not change what I said in terms of preparation of the substrate.

Perhaps I should have also added that primer-sealers actually do create a chemical bond as well as a mechanical bond when a layer of paint (or in this case... gesso) is applied within approximately 24-48 hours. That's one of the reasons why they feel slightly sticky at that time, where as a week later they will not. And sanding of course of any surface (i.e. varnish, shellac, etc.) will not recreate this tackiness.

Again... my last post was fairly long and many may have found it too long as it was. Readers like to read... painters like to paint. :)

There is so much to know and so much to say... it is why initially (i.e. my last post) I stated that for those that simply wanted to know what the safest method was... simply read the next one or two paragraphs (paraphrase).

I have had university students get their BVDs so twisted by all of the 'but-what-ifs' that they became virtually intellectually paralized and created very little as a result. And it is one of the reasons why teachers often do not teach the correct (read: archival) method of preparing hard boards. It would cut-in to the actual painting time and very possibly make the surfaces so 'precious' that the students would be overly careful in experimenting.

Students have reminded me of Doestoyevsky's protagonist in "Notes from Underground." ("Emotions allow us to make decisions - pure logic often would not." - F. Doestoyevsky)

What I said stands.

I must paint now... not talk. (re. above;) )

I __only__ wanted, somewhat briefly, to post so as to save painters the lost time and problems I have seen occur for myself and others.

If you want to work in another way... by all means... please do. Just don't talk... work. We painters need something to show for our time. ;)

RonL
03-16-2009, 09:51 PM
Sometimes sable brushes can manipulate oil in ways that bristle brushes simply can not. (referring to my last post)

Here is a detail of one of my paintings as an example. (click) (http://www.theimagecache.com/images_for_forums/passion_closeup.html)

Einion
03-17-2009, 07:07 AM
For all practical purposes, what I indicated in my original post is true for any circumstance I can think of where the art will not be exposed to incredible environmental conditions.
The thing is Ron, it is not the final word - which is sort of how you presented it - it's just one man's opinion.

I don't want to turn this or my original post into a 'food-fight' which I have seen happen on these forums where someone comes along and dissects each-and-every paragraph even to the extent of semantics, grammar, and minor typos. (Truly unfortunate since this website on average is excellent.)
That's fair enough, you don't have to respond.

But if you won't defend statements or technical details - presented as facts, as you did - then I'm sorry, it comes across that you can't, not that you're unwilling to.

In all fairness there was so much that needed to addressed. Just on the most basic materials level there aren't commonly tempered and untempered types of MDF. MDF and hardboard are completely different. There are no oil-based gessos (given that I'm merely guessing at this point that you're referring to the acrylic primer often used today, not primers generically as gesso :confused: ).

This type of thing completely devalues the rest of the information in a post, sound or not.

But the "unintentional flexing that will create micro-fractures" bit toward the end is one example where quite frankly I was scratching my head, wondering where you got that from. I'll even go so far as to say it sounds made up.

Rationales aside... i.e. one person's 'food-fight' is another's search for specificity and truth...
Indeed. Should be easy to see that's what I'm doing asking you to clarify some of the things you referred to or seeking evidence to back up a claim!

Perhaps I should have also added that primer-sealers actually do create a chemical bond as well as a mechanical bond when a layer of paint (or in this case... gesso) is applied within approximately 24-48 hours.
What relevance does this have to the use of acrylic 'gesso' as a primer for oil painting? It is usually an extremely bad idea to paint water-borne paints onto oil-based paint until after the latter is fully cured.

There is so much to know and so much to say... it is why initially (i.e. my last post) I stated that for those that simply wanted to know what the safest method was... simply read the next one or two paragraphs (paraphrase).
Safest in your opinion. There are plenty of other people working today in various parts of the art world whose recommendations wouldn't be the same.

Einion

jdadson
03-17-2009, 02:33 PM
Quarter inch MDF is all that I use for smaller paintings - 18X24 and under.

I prepare it with three coats of sanding sealer, sanding after every coat. Do both sides to avoid possible warpage. Sometimes I paint on it just like that, but usually I apply a coat or two of white paint with added chalk and turps. Sand after those coats also.

Gesso is not necessary. The old masters used gesso (chalk and glue) on their panels to hide the wood grain. MDF does not have wood grain. So-called acrylic "gesso" is evil. The standard kind has a hard grit in it that's impossible to sand, and will eat your brushes for lunch. The grit is necessary, because acrylic paint is too slick. There's a company that makes a version for panels that you can sand, but what's the point? Best just to avoid it.

I've tried true gesso on panels, but I didn't care for it. Too absorbent for my taste.

jdadson
03-17-2009, 02:49 PM
Note to Bill Martin. (Hi Bill!) The MDF that I use is totally non-porus. If it weren't, it would not qualify for the "M" in MDF. However, I once bought a sheet that was labeled MDF that was not suitable. I test it by putting water on it. It it forms a bump where the water is, I figure that's not good. It's only happened once. The stuff that my local Home Depot is carrying now is quite good. Or was the last time I bought some.

jdadson
03-17-2009, 03:11 PM
RonL, I'm using ZAR (brand) quick dry interior oil-based polyurethane clear satin sanding sealer. Is that a good choice?

jdadson
03-17-2009, 03:29 PM
Note to RonL. Einion is correct in that oil-based gesso is not usually called gesso. "Gesso" literally means chalk or gypsum, so oil and chalk should have a better claim to being gesso than acrylic gesso does, but that's not the current usage. I make my own panel primer from white oil paint and alabaster chalk with suitable amounts linseed oil and turps.

RonL
03-17-2009, 06:35 PM
Hi jdadson,

The only thing I would be concerned about is that even sanding sealers (and I have used them extensively in the years of wood work I have done) are not made to seal tanic acids that may occur in fiber boards if some woods have been included in the mix. (e.g. redwood or cedar) I am not saying that such sanding sealers do not exist... only that I am not aware of them if they do.

I have never known of anyone using or suggesting that a sanding sealer should be used on redwood or cedar (not that you are). And I would not trust a work of art to the assurances of a manufacturer of fiber boards that they have not (perhaps accidentally) included redwood or cedar chips or such wood dust in their product.

We've probably all seen the labeling on some organic foods that carefully state "This product has been produced in an environment that also contains peanuts, wheat, __ :confused: , etc." So why would this not be possible at a huge wood plant where there may be the possibility of mixing of dust and chips? For construction work there probably would be absolutely no downside to this... but for a painter that would like his/her painting to last for decades... it could be a factor.

This is why I feel it is more archival to apply a primer-sealer that is made to prevent such acids from working their way in to a painting.

I'm sure there must be other manufacturers that also make such primer-sealers (other than the ones I have listed above). Just make sure to look on the can's label and if it does not very specifically state that it seals tanic acid I would (personally) not use it.

I am not saying that my way is the only way... just that I am certain this method will lock in acids contained in the mixture of the various woods used in fiber boards.

"...oil-based gesso is not usually called gesso."

I think if you read my posts again you will see that I never used the term oil-based gesso or oil gesso. Someone else must have misquoted me. Hmmmmm... Hopefully it wasn't done to create a 'straw man.'

But I certainly won't argue about the current usage of the term. However, Daniel Smith does have a product they advertise as being an oil gesso. For whatever that's worth. (?)

What I had suggested was to use an oil primer-sealer and then listed the manufacturers and names of the ones I have used. And I said that the water-based version is fine to use as well as long as enough coats are applied.

After applying one of these (on a small, rigid surface) an acrylic gesso is fine to use. Of course I would never use an oil primer of any type and then apply a water-based product over it on a flexible surface. I might add... that it is best to do so soon after the primer-sealer has dried. Primers have what is known as an 'open' period. After this the locking-in of the next applied layer will not be quite as good.

And again... I can not stress strongly enough... if someone has been using another method and products... and they have worked for you... then please continue. I am not posting to refute others' findings. I'm only saying be aware that it is important that all sides be primed/sized (i.e. edges also) and that it is done with something that will lock in the corrupting components in the fiber board.

Enjoy your oil painting!

jdadson
03-17-2009, 07:24 PM
Thanks, RonL. The only caution on the label of the stuff I have is not to use it on wood fillers or finishes containing stearates. But I will try to find out if it's okay in general. If I can't get the info, I'll look for the brands you named.

Again, the reasons I don't use acrylic gesso are, 1) it's almost impossible to sand, and 2) it destroys brushes. I was going through brushes like crazy before I figured out that acrylic gesso was the culprit.

donn_granros
03-17-2009, 07:25 PM
Ronl.. Initially -welcome. I'm not a big deleter (or debater either) but I think you were going after Einion a bit aggressively. IMO, it adds nothing to the dialog. Most of my recent work has been done on MDF which a friend of mine manufactures and markets so the subject and comments are of great interest.
Much appreciate the dialog as I'm guessing many out here do.

Eduardo Flores
03-17-2009, 07:40 PM
This is a thread on a very interesting issue regarding oil painting: please stay within the limits of this issue, avoiding comments of personal nature that in the first place may be offensive, and in second place are certainly out of contest.
This is the only way of maintaining the thread alive.

Eduardo

jdadson
03-17-2009, 08:13 PM
deleted

donn_granros
03-17-2009, 11:22 PM
It is important that we remain civil. Einion has made many decent constructive comments over the years. If he chooses to show his art or chooses not to it is his choice just as it is for everyone else out here.

1100ww
03-17-2009, 11:48 PM
Since acrylic gesso is so hard on brushes, would a couple coats of white oil paint (on top of the gesso) provide a bit of "cushion", as well as sort of simulate an oil ground?

Also, is shellac a proven/acceptable sealer + and an alternative to gesso (on rigid panel)?

digitalis
03-18-2009, 01:41 AM
I haven't been following this thread so please forgive me if I am digressing, but in response to this quote from Einion - "There are no oil-based gessos (given that I'm merely guessing at this point that you're referring to the acrylic primer often used today, not primers generically as gesso" - I thought I would mention an Australian product I use specifically for prepping for oil painting - Art Spectrum Oil Primer which is an oil/acrylic resin blend with 40% linseed oil, and washes up in water. Try www.artspectrum.com.au for details.

jdadson
03-18-2009, 03:53 PM
Since acrylic gesso is so hard on brushes, would a couple coats of white oil paint (on top of the gesso) provide a bit of "cushion", as well as sort of simulate an oil ground?

Couldn't hurt. Just keep it lean. Thin it with mostly turps rather than all oil. But why use the acrylic gesso at all? Maybe you already have.

budgiehawk
06-15-2009, 12:53 PM
MDF is typically used in high-end furniture meant to last. It's advantage is that it does not tend to warp or delaminate. It makes a great painting surface. I got advice about primers from a guy working for Gamblin who can get pretty much whatever he wants. According to him, PVA (poly vinyl acetate) glue is the best primer. Unlike rabbitskin glue it does not absorb water. It is really stable and cleans up with water. He's using it both for priming the boards (all types!) and sometimes for glueing canvas to them.

Who knows when you'll get lucky and paint something you want to last. It is my understanding the MDF should last as long as anything else.

Nilesh
06-15-2009, 06:59 PM
MDF is horrible if it gets wet. It's best to seal it thoroughly.

Those who have compared the two tend to agree that quality tempered hardboard is probably a better choice for a painting substrate.

According to Golden, some PVA glues are not archival. They vary, and some are better than others -- archival PVA size from Gamblin seems to be one of the better products.