Trupan Ultralite MDF

[billp]

Has anyone out there been cutting Trupan ultralight MDF? At the Oklahoma Camp Joe Crumley showed us some beautiful signs he had carved in the material. It appears to be somewhere "in between" styrofoam and HDU in terms of composition ( and certainly pricing..). Being made mostly of Pine it also does not have the formaldahyde glue to contend with, so it should be much easier to work/live with in the shop.
I understand that it does not have much structural integrity of it's own, but I would probably be coating my finished pieces with epoxy anyway. From what I could Google about it, the main use at the moment is as a substrate in the furniture industry. Has anyone been cutting it long enough to give some feedback? Thanks..

[jeff_b]

Hi Bill
Here is something from Dow chemicals that is just starting to show up in the marketplace.

http://www.dow.com/bioprod/prodapp/index.htm

[billp]

Jeff,
Thanks, I just sent them a note asking about availability in my area. I, and a lot of other people, are looking for a material that will come in sheet form, and can generate a relatively smooth,workable finish when completed. Trupan seems to cover that from what I have seen so far. It's just that a lot of these places will not ship small quantities, and I'd hate to stock up on materials I won't have much of a use for. The local distributor here quoted me a sheet price of $27 for .75" full sized Trupan panels,so it's attractive on that end as well.
I'm trying to get my hands on all of these new materials so I can see if they are worth the investment. And hopefully if I get some samples in the next few weeks I can carve something from it to bring to the Jamboree with me...

[elcruisr]

Bill, I've cut up several units of the stuff and use it in my shop. It's great stuff. Machines nice and clean but it will "shear" small raised letters off just like regular MDF. It's also sure easier to hoist around the shop since it's lighter. There is also now an exterior rated MDF called "Extira". Tried a sample and it works well but I don't know about the chemical content. It does have a warranty for exterior use but it must e painted.

Eric

[kerrazy]

Hey guys the extirra sitting out side my shop literally in a puddle of water with no finishing (paint or other) since Dec 18th is holding up nicley. A small and I mean small amount of swelling where it sat in 6 inches of water off and on for several days. It is sitting on its side so all edges have a chance to get beaten down by the weather and so far so good. It has endured rain and torrential rain, Sudden freezing, drops of -30 deg celcius and a winter full of snow. So far so good. It is real heavy and loaded with phenolic resins, so a mask and back brace are definatley in order.
Dale

[billp]

Eric,
Thanks for the info.
What does the surface look like after machining? Is it really "fuzzy" requiring a LOT of cleanup sanding?, Or do you think it could generate a smooth finish if a small enough stepover was set for the router bit? I'm doing a lot of "sculpting" with the 'Bot lately and I'm looking for a material which will let me minimize the post carving clean up work. I did get a piece of the Extirra, but it didn't cut much differently than a particleboard would. I'll be finishing most of my pieces with the water based metal coatings, so I don't care about color, etc. If this material is what it sounds like, I think a lot of people might find uses for it. Not easy to find though.

[joe]

Dale

The product "Extirra" is very interesting and I am interested and really appreciate your post.

A few years ago we purchased "Medex" which was also advertised as an exterior fiberboard which proved to be a total disaster for us, so you must understand our hesitation with Extirra.

Please let me know how if it routes cleanly, is it very heavy, does it sand well, and how much does it cost for 3/4" stock.

Thanks for your trouble.

Joe

[elcruisr]

I've done some pocketing work and signs with the Trupan. It will give a pretty clean job but it is sensitive to tooling when doing area clearing. I get some of the best results from "O" flute tooling with very little rake in the tip that's more for plastics. It will clean up easy with fine sandpaper if there's any overlap marks.

Eric

[rookie432]

Bill,

Been using Exterra mdf quite a bit lately. Dale is right, holds up to extreme weather quite well. Had a 1" and 1/2" sheet leaned vertically against the outside of the shop for six months over the fall and winter here in Ohio. Rain, sleet, snow, hail, and sun didn't have much effect. It did bow slightly umder its own weight so I flipped it and it straightened up a bit. It still is a fiberboard so fine detail cutting will result in some fuzzyness however sands very quickly and holds shape. I know you use epoxies so smoothness can be attained.
I have one commercial sign installed begining of winter. Looks great today but time will tell.

Ironically I also have a sample sign made of regular mdf mounted on the outside of my shop. Primed and painted. Same result??? I guess if sealed properly it will hold up.

[rookie432]

Here is an exaple of finished exterra product. Takes oil based paints well
4814
4815

[rookie432]

a little crisper pic.
4816

[joe]

Bill,

Since our last conversation about Trupan, I have tried using epoxy on V carved area's. My findings are: It sands so nice, it accepts the expoxy in the carved area's extremely well, but has a rather rough surface when dried, second coat of epoxy smooths it out but not enough, third coat does the trick but obscures detail.

Trupan has some weaknesses but all in all it is a great product for us.

I have searched all the local lumber yards here for Exterra with no luck, but Weyerhauser called today and is sening a half dozen sheets of a product, they calim, is better than either Medex or Exterra.

I will be sending you a few pix of our latest carved sign.

Joe

[bleeth]

Bill: The major difference between light and ultra-light fiberboard like Tru-pan and the old standard MDF is the compression in manufacturing combined with quantity of material. Basically, the lighter versions simply have more air in them and so even though they sand easier the machined edges are more porous and may require more sealer for a really clean and smooth finish. Whether they are made of radiatta pine, as much of the South-American product is or other types of dust, the chemical bonding content varies from manufacturer to manufacturer and usually does contain formaldahyde unless it is specified such as in a product I used to buy in the Northwest called MDF Free. For the best painting surface of a milled edge the higher the density (and hence heavier the weight) product the better.
A side note-Sallye told me that by milling both surfaces off MDF and MDF light you can pull a vacuum through it-There's an idea!!)
Dave

[bleeth]

Hi: Has anyone out there carved thermofoil doors with a decorative pattern? I'm wondering about a good speed and rotation for a 60 degree bit around 3/32 deep so I can get the job done in a reasonable amount of time without putting a burn or a burred edge on the PVC.
Dave

[artisan]

Joe....try priming the Trupan with Zinnser white shellac before using the epoxy. Zinnser forms a vapor barrier and dries quickly because it's alcohol based. This should keep your epoxy coating from being absorbed and should let you get a smooth finish with one coat, thus preserving your detail....D

[joe]

Dave,

Thanks for the information on Turpan.

We began using it a couple of years ago when one of the SB users mentioned you could pull a vacuum throught it. Soon we started using as a carving product.

Bill P. and I both discussed different sealing methods to make it more durable outside. My first test was with Shellac based sealers, but it is too porus. One has only experiment to see how this works.

When doing V Carving, the dust gets airborn fast. I would suggest wearing a even with a good vacuum. The dust doesn't seem to me, to be unpleasant as does MDF.

The carving limitations has to do with small deliclate detail.

Warehouser is sending us a half dozen sheets of a new product that is to compete with Medex and Exterra. We wil see how it does.

Best Carving.

Joe

[tberkner]

I've been using ultra-lite fiberboard for a few months. Probably gone thru 100 sheets. No problems yet. The most intricate work I do is create a Gothic window (the pointed church type) with both trefoils and quartafoil and 3 levels of tracery. I then paint it with flek-stone or granite stone to make windows for miniature chapels. The windows are 4" x 8". I cut it with a cheap 1/4" Grizzly straight, 2 flute bit. Doesn't require any sanding. It is cut on both front and back sides, so alignment is very important to me.

Due to lack of strength, I had to find the proper cutting order by trial and error. Narrow pieces tend to become detached.

[ddewees@gmavt.net]

I do museum exhibit fabrication in Vermont and am bidding a job that calls for 2" lightweight MDF. From what I have read Trupan should fill the bill. Who distributes it in the northeast?
Don Dewees

[benchmark@tesco.net]

Hi Don
I have no idea about suppliers in the northeast as I am in the UK, one thing to bear in mind is the type of items you work might house as some museum's do not like materials that gas off Formaldahide and other weird chemicals.


Paul

[billp]

Don,
I've been looking for a distributor myself, and I've had little luck. One source, Atlantic Plywood in New Jersey claims they have it in stock, but the samples they send are NOT Trupan, just another generic ultra light made with formaldahyde glue etc...(There are other Northeastern branches of Atlantic, you might have some luck with one of them..).
The "Lumber store" (www.lumberstore.com (http://www.lumberstore.com))in NYC has it, but I'm not going to drive into Manhattan in my van for a few sheets of plywood...(No shipping, I checked..). Google has a couple of pages about the product, but few leads in the Northeast. If You, or anyone finds it, please let us all know...

[ddewees@gmavt.net]

Thanks for the input, Bill and Paul. I'll see what Atlantic Plywood has to say.

[billp]

Latest lead for Trupan is Russell Plywood, (www.russellplywood.com (http://www.russellplywood.com)) They have locations in Delaware, and Pennsylvania. Their South Jersey rep - "Jim" (609-254-0123)said they also have another ultralite from Chile in stock as well. I've asked for a sample to double check and see if this is what we are really looking for. I'll pass along any info I learn..

[elcruisr]

I'm lucky in that Dixie Plywood stocks Trupan for central Florida. The problem, as explained to me by another wood supplier, is that Trupan is only sold by the railcar load. Not every yard is willing to bite off that big of a load and than sit on it untill it all sells.

Eric

[brett_stahl]

Has anyone worked with the Woodstalk Machinable Fiberboard MR product from Dow yet? I'm curious to hear how it performs.

Also, does anyone know of a Trupan Ultralight dealer in or near the East Tennessee area?

Thanks - Brett

[billp]

Brett,
You might want to try and contact North American Plywood, (www.naply.com (http://www.naply.com)) they seem to be a major East Coast distributor and while at the IWF Show John Forney got some good leads from them.
To follow up my earlier postings on this thread I did buy 5 sheets (their minimum order for free shipping) from Russell Plywood, and the stuff is really nice to work with... It holds a sharp edge, carves easily, and does not produce the toxic cloud of formaldahyde which standard MDF does...
Shipped to my door a 3/4"sheet costs $25.50 ( and that's after they trans ship it from their Pennsylvania yard to their Delaware depot to then ship to me in New Jersey...)
One side benefit I had not anticipated was that unlike plywood while cutting Trupan you don't get that screaming sound of the PC router....

[andrewm]

Has anyone painted Trupan? How does it paint. We are currently using 3/4" double processed door grade MDF which paints really well, but is very heavy. We found that with a lot of standard MDF any carrving we did were always a bit fussy and required a lot of sanding between coats. Does Trupan ultralight fuzz?

Andrew

[Brady Watson]

Andrew,
It paints fine...but yes, it does fuzz. The nice thing is though, it sands much much easier than MDF. You can literally 'wipe' sandpaper over the hairs to get them off. Great for 2D and some V-carving, not advised for 3D work that requires a lot of sanding.

-Brady

[billp]

Andrew,
I'll second Brady's opinion. It cuts easily, and sands very quickly. I think by the time you get a primer on Trupan it's already got a good workable surface...We're trying to switch everything we can over to Trupan just for the ease of moving the sheets around the shop...

[jseiler@bluemarble.net]

> Great for 2D and some V-carving, not advised for 3D work that requires a lot of sanding.

What does work well for 3d work that doesn't require sanding? Is there anything relatively vacuum porous that works well for 3d?

John

[Brady Watson]

John,
Foam is by far the best for cutting 3D and you can sand it with another piece of foam...Start playing with insulation foam before you spend money on 15+ lb density foams, as they are much more expensive.

No matter how you slice it...you are always going to have to do SOME sanding with 3D. The 1st thing to do if want to reduce sanding is tighten up the stepover on your toolpaths. I typically run an 1/8" ballnose at .0125 or less stepover. The cost of this is longer milling time, but it yeilds a nicer surface. For my tastes, the optimum range is between 7 and 10% stepover depending on the file and bit. Lowering it to 1%, lets say, gives no advantage.

-Brady

[billp]

John,
You can take Brady's idea to the upper end and get some of the "tooling foams"etc. which have been used for doing die/mold making for years. VERY tight densities ( I have some here that are 80 lbs sq. inchs..) I have also broken carbide end mills while cutting "butter board"another high density foam ( 44 lbs..). These foams have NO fuzzies, but you need to get your tooling dialed in pretty well. If not you could have a lot of cusp grooves showing on the surface of your material, and THEN the sanding would be a nightmare ( think of sanding a bowling ball with fine grooves on the surface.....).
"REN" board is another species with similar properties for tooling.And you can get blocks of machineable wax if you are looking to cut "masters"for molds.
A lot of the material choice has to be based on the ultimate use of the 3D part being cut. The trade off with carving insulation foams is that it takes more man hours to prep/prime/coat the pieces than some of the higher density foams, but it's initial cost is forgiving enough to allow you to do some experimentation and find out what surface works best for your needs. There are now enough good coatings/primers ( MAS epoxies, Styro Spray, etc.) so we can really USE good finishes on any grade of foam.

[beacon14]

Bill I sincerely hope you meant 80 lbs per square FOOT!!

[jseiler@bluemarble.net]

can one vacuum form over insulation foam? It seems like it would melt or crush. I was hoping to find something that 3d machines nicely and will allow one to draw a vacuum from the backside of the buck (required for fine detail) without melting too much. Wanting to vacuum form petg and maybe abs with 3d bucks cut on the bot.


john

[joe]

There are several products in the foam family which should work.

HDU, High Density Eurathande:
Sign Foam
Precisions Board
EverWood

Most Sign supply houses have them in 15lb and 18lb but can order pieces up to 80lb. There is no fuzz and sands easily.

[Brady Watson]

David...No, it REALLY IS 80#s/inch! Wild stuff...made from black hole dust and swamp gas from Venus...LOL!


John,
If you are looking to use it for vacuum molding, then you might want to use RenSHape like Bill suggested. You can find a variety of thermo compatable grades here: http://www.freemansupply.com/RenShapeToolingand.htm

It does of course, depend on what you are acutally molding & more importantly how many you intend to pull from this buck during it's lifetime. You can do pretty well with Trupan and coat it with epoxy. DuraTec (nasty polyester...beautiful product/results) OR coat it
with a high-temp tooling gelcoat made to withstand higher temps and cycle times. The Duratec is a nice product for resurfacing fiberglass molds, or for surfacing mold-less products. Many furniture shops use it to coat MDF into a glass-like smooth surface. Nice stuff...I just hate polyester products with a passion...It's the smell.


-Brady

[fleinbach]

I checked locally for Trupan and found it at Atlantic Plywood just south of Baltimore. I asked them to be sure it was Trupan and they assured me it was. They carry only 4 X 8 Sheets in 1/2 and 3/4 nominal. The price was $17.90 and $23.43

I then called Chesapeake Plywood in Baltimore and they claim to have it by another manufacturer. They said there material was made from the same pine as Trupan. They where not sure about the glues though. They have it in several sizes up to 1" and sheet sizes up to 5 X 10. They where a bit higher priced even if purchased in volume. There price for 1/2- 3/4- and 1" respectfully was $22.62, $27.52 and $46.78.

I noticed pricing is a bit strange. Consider that 3/4 inch material being 33% thicker then 1/2 inch only increases in price by 21% while 1" being twice the size is more then double the cost. I guess since 3/4 is the most common size it is also the most economically priced.

[Brady Watson]

Hey Frank,
The 3/4" stuff works out to be 18mm or .70" thick...Something to consider before buying. I think it is a great product and perfect for routing, but I would use discretion in a structural application since MDF is noticably stiffer than the Trupan.

I'm guessing that the deviation in price is like you said...quantity. I believe that they have to buy an entire railcar full to get it in stock.

I was also told by another botter that the stuff Chesapeake is peddling is NOT Trupan & NOT the same composition. It is inferior to Trupan. I haven't tried the stuff 1st hand, though.

-Brady

[fleinbach]

Thanks Brady,

I realy didn't like the pricing at Cheasapeake either. If you saw how large there operation was you would think they should actualy have the lowest price, There wharehouse takes up the better part of a city block with every inch filled with various types of plywood stacked over 20 feet high.