Do you use MDF ?

[Jill Marie Welsh]

Thanks, Rob!
Another reason for me never to use MDF (we call it MDO)
I hate that crap.
My lumberyard is always trying to shove it down my throat
(the splinters are painful!)
But I hate it because the paper coating invariably breaks down.
I see signs all the time that have been done on MDO.
The lettering is holding up, but the background looks like it needs
Pro-Active acne solution!
I try to use Alumalite whenever feasible, if not that,
I buy exterior plywood, prime it well, sand it,
then use 1-Shot as a background.
Vinyl sticks to it quite well.
Love- JILL

[Robert Lambie]

i agree with you jill.. i see stuff made from it thats pulped after a short time.. we are actualy redoing all the signs for a pub that had all its previouse signs done in MDF. the signs looked brill when they went up.. i saw the sign company fit them as it is close to my home.
now they look awful.

if steve broughton reads this ide be interested to hear if he has any stories like this..
steve uses the stuff alot and never seems to have any problems.. infact some of the stuff he does looks amazing.. im not sure if its because hes applying gold leaf to it thats maybe protecting it more or if its a special coating he uses on it… 🙄

we really only use the stuff for a waste board on our CNC router table.. it has to be replaced ever couple of days or more if cutting many small letters ontop of it..

[J. Hulme]

Errr no. MDF or medium density fibreboard is just highly compressed wood dust bonded with a resin than contains carcinogenic promoting chemicals such as formaldehyde, if you attempt to cut this stuff you should be tooled up with full face mask and breathing gear, the HSE has being trying to ban this cancer causing rubbish for years.

It’s only use is of making cheap MFI type furniture.

[Gordon Forbes]

You get an exterior MDF for use outside.

My brother in law is a joiner and he says to use it outside you really need to coat it with marine varnish or similar to seal it.

I will tell him of this about the sawdust when I get back.

[John Singh]

Thanks for the warning Rob

Before I came into the sign game we used this a great deal in constructing cabinets and shelves and other stuff.

but I knew then it was carcinogenic so we always wore goggles and mask.

If you were tempted to do that little job that would only take a mo’ you usely paid with the dust being in your eyes for the rest of the day. So we made it a habit to wear our stuff.

There have been occasions where I use MDF today but it is always the exterior brand (about triple the cost of ordinary MDF)

As I say I am using it less frequently today

There is a brand of MDF that is formaldehyde free but you have to order this in specially as most timber yards do not stock it

Extreme care must be taken with this stuff as Rob’s story points out to readily.

The mills have special huge extracters to whip away the dust as soon as it is cut

We hope your cousin doesn’t lose his sight Rob

John

[John Childs]

A comment I have read somewhere recently, it may even have been on this board……

“MDF is the new asbestos”

[Phill Fenton]

I never use this stuff for signs but occasionaly use it for DIY projects at home. I had absolutely no idea it had such a reputation for being a health risk. I will be very careful with it in future 😕

[Tim Painter]

If my grey cell…..(only 1 left now too much Jack last night) serves me correct.

Wasn’t there also something about certain finishes causing a reaction with MDF and giving of gasses?

Tim

[Andrew Blackett]

I sand down brass on an mdf worktop when I’m in the workshops. I’m always hacking my guts up so I dread to think what it would do to someones eyes. Think I’ll cover the top in some s. steel sometime!

Andy

[Duncan Wilkie]

Hi Folks,
Just a couple of notes:

MDO is Medium Density Overlayed Plywood. Usually a spruce plywood core with a resin coated paper laminated to the face and back side. Not as good as the fir plywood core they used to use, but we still use a lot of it with good results. Always use G2S and fill and paint the edges and backs.

MDF is Medium Density Fibreboard. Compressed saw dust, for interior use only. Very stable material, but very heavy also.

Medex is an exterior grade MDF. Must be totally sealed including any holes. Edges need to be eased to better accept the coating.

Cheers,

[Steve Broughton]

Err Rob have you never heard of Safety Data Sheets then matey? as an employer its your resposibility to know this stuff and inform your staff on the correct use of materials. Same goes for your cousins employer if they didn’t advise him on the correct machining and safety measures for using MDF the they are in the poo and If I was him I’d sue their arse.
I use EXTERIOR GRADE MDF sorry to shout but I get fed up with telling people, yes you can use it outside and no it won’t blow like ordinary MDF and yes you have to paint it properly with good quality paints not that rubbish from Wilkos or Woollies, to anyone who says you can’t use it outside then I’m sorry but you are talking out of yer backside, use the proper stuff Exterior Grade MDF paint it properly (by properly I mean exterior primer and undercoat and then 2 coats of exterior gloss front and back) and it will last for years, ask my mate Paul Rafferty he’s been using it for 12 years with NO Failures What So Ever!!!!

On using dangerous materials, when I worked as a printer we used to use all types of dangerous stuff but because we where taught to use it correctly we never had a problem, 2 such materials where Toluene a base solvent that is very nasty and another was a plate etch that if burnt gave off Phosgene gas, this was was the stuff that the Nazis gassed 6 million Jewish people with, but because I used it with care and resposibility I’m still here. OK

[Bill Dewison]

Steve, is the exterior grade MDF the one with the greenish centre? I recently bought lots of 1″ MDF to build pillars in the bathroom here, and this was s’posedly exterior MDF. The only difference I noticed was it was a little harder to cut with hand tools, it was damned heavy (mind you, most sheet materials are at an inch thick) and it had this greeny centre to it, made it look like some sort of sandwich. 😕 I’ve looked at B&Q warehouse for exterior grade sheet materials, but have never come across them. Where is the best place to look for it? This is a wild guess here, but even if the 1″ MDF is exterior grade, I think it may be a little heavy for signage use. 😮 🙂

Cheers, Dewi

[Henry Barker]

Dewi it sounds like you have ext mdf, when you look at the sides it looks like a sandwich although its impregnated right through.

Medite or medex are exterior brand names, I got a brochure here from Willamette Europe on Technical recomendations and specific end users, its really informative on cutting machining sealing, painting etc. Often failures occur because whatever the material paint doesn’t like sitting on 90 degree joints or angles weakest resistance, so rounding corners is a good idea….etc etc, as Steve says proffessional finishes rather than hobby crap.

Jill I think Duncan pointed out MDF is not MDO, which I believe is what we call plywood 🙂

There is a big list here (6) 🙂 of the diffrent glues and their use with mdf, etc.

Sorry to here about your cousin Rob, I think we all have to think about how we work, HDU must also contain some great chemicals when sanding, and does styrofoam when you melt it, and although we are not all exposed to these every part of everyworking day alot of us are exposed to alot of stuff at different time and because of infrequent use may not take adequate safety precautions.

http://www.willamette-europe.com

[Steve Broughton]

Dewi if its a green colour then its medite 313 which is moisture resistant and is often used by builders in bathrooms and kitchens, you’ll waste your time trying the big DIY sheds (B&Q etc.) for exterior mdf as you will only get blank looks, try a dedicated timber merchants / wood yard as they will be able to help and as to thickness I use 9mm. Try this website
http://www.weyerhaeuser-europe.com for more info.

[Bill Dewison]

Thanks for that Henry & Steve. I’ve spoken to the timber merchant that supplied the ’25mm’ MDF (apparantly they no longer understand imperial measurements 😉 I say an inch, they say 25mm) and they don’t sell it in any other sizes, so it looks as if I’ll need to find a new timber merchant. They say they use it as infills for exterior doors, sandwiching it between other materials. I mentioned the Medite product name and got an almost B&Q response, “Durrr, not urd of dat one”.

I like the idea of making stuff in MDF though. You’ve shown in a few of your demos Steve how versitle it is, I’m itching (hopefully not from the dust 😉 ) to try out making some lettering 🙂 On the subject of dust extraction, I’m hoping to erect a canopy outside the backdoor of the workshop for cutting sheet materials that’ll produce lots of dust. Hopefully it’ll mean I have no need for an extractor or the like.

Is the One Shot enamel paint the most commonly used to paint MDF? I noted in one of your demos Steve that you used a Crown product, is that instead of, or in addition to the One Shot? Also, is car body paint suitable for Medite/exterior MDF? I noticed Mike uses grain-filled boards that are primed and ‘blown over’ with car spray paint, but I think the sheet material was plyboard. 😕

Sorry I’m asking so many questions with all this, I really should buy some stick on L Plates from Alan, slap one or two on my back now and then 😉 😉

Cheers, Dewi

[Henry Barker]

I handcut letters and logos here, have a giant Jonsereds Bandsaw and Hegner scrollsaw (rolls-royce in scrollsaws). MDF is heavy going, I like to cut out letters in forex or similar its available up to 20mm and can be coated with most products, I have sandblasted MDF, get a nice effect, I also cut out letters in HDU foam like Precision Board or Sign-Foam, and then paint them with car paint, you get a really deep rich colour on the letters. You can use one shot too, we have One shot here and Deka which is dwindling as the factory closed….Painting an old metal sign today with One Shot.

Funny they haven’t heard of Medite the link we gave you is to one of the worlds largest producers!

Send them a mail and ask for the Technical recomenadations and End users brochure, they are fast and it answers all your questions and is a really handy piece of info to have around ask them also who they supply close to you.

[Robert Lambie]

hi steve
couldnt agree more with you mate.. honestly. 🙂
when i went into work the following day i told the guys that work with these types of materials exactly what i have said. i also told them i didnt want to catch them without eather a resporator if working the CNC router or dust masks if only using it for this and that, goggles included.
ive also had a sign put up in two workshops and router room.
my point on the stuff was basicaly it was all news to me.. and i bet many others too.
B&Q warehouse throw this down peoples throat daily. but i never see the guy cutting it in front of a gallery of customers with any kind of mask or goggles. surely its their job as the supplier to educate us the customer.
if they do we inturn tell our staff.. but if its sold like cigarettes. nobody will really takes any note until the damge is done.
my cousin has been a joiner for years and is self employed, he says although he had been told by “other joiners” that the stuff is bad on the lungs he had never been told he could go blind from the dust.

as for the exterior stuff, yes.. medite rings a bell now. 😳 i wasnt trying to imply you used the interior stuff, just that i knew you used it often and wondered.. like i said ive seen some cracking stuff you and your mate paul has done using this.. infact a while back i did my first gold leaf letter in the stuff.. “but i used the interior stuff.. only for a test though. it never went up.
have you ever tried HDU foam, Sign Foam – Precision Board ? this stuff is amazing to work with. cuts like butter, even with a stanely knife.. comes in many thicknesses too.
i could easily use this stuff daily, but i feel its a little expensive for cetain types of job. 🙄

[John Singh]

Is Signfoam similar to Signrock?
Very light weight?

Where is the supplier for this stuff?
and what kinda price is it for a sheet?

John

[Henry Barker]

John Hartbrights in Manchester sell Precision Board, Bill Rae, and Corian Distributors (Corian) in the UK sell Signfoam, a 15lb density board 8×4 is about £350

Nobody sells it here anymore, and the £ is high against the kroner plus the freight, so we use 2 companies here in Sweden and glue smaller sheets together, you can specify the density from one company ans so the finish is much harder 300g density or 370g from another supplier, much better finish than Spandex Signroc or Signfoam.

Weight depends on density I guess what I use is eqivalent to 18lb density or thereabouts.

[Robert Lambie]

henry i think i bought my stuff from springwell sign supplies.
its about 1 inch think and about 5 foot by 3 (thats a guess.)
think we paid about £60 (again a guess)
after seeing a demo in sign craft i decided to give it a go.
i didnt spend much time when it came to painting it.. i basicaly got it cut.. sanded the face so it had a radious (easily) then spray painted it with a filling spray repeated that then spray painted green.
that was a few years ago. not so long ago a single letter come down but did not break. i went up and refitted it.. i was amazed at how perfect my paint work was and that the letter had not warped in anyway… 😮

john, it maybe an idea to get springwell to send you a sample mate..

henry i know you do huge foam letters for tv sets and the like. what do you paint these type of letters with. doesnt the paint melt the foam at all?
polystyrene that is. 🙄

[Nigel Fraser]

Guys,

I use these people for sheet timber supply –

http://www.edens.co.uk/

They have several depots, but I think they are based kinda midlands downwards.

But their site gives good ideas of prices (Medite 9mm 8’x4′ is about £20) and product details.

Hope thats some help anyway….

Nigel

[Henry Barker]

I haven’t heard of Springwell….but thats not surprising, I forgot to mention that the Signfoam is 2″ thick and was around £300-£350 a sheet there are big differences in HDU and it depends on how you are going to use it, it does not warp, check crack or rot, it is a closed cell structure and therefore does not absorb water, acn be painted with just about anything.

As you mention a filler primer is a good start and then lettering enamel or car paint is what we use.

For large polystyrene I use water based acrylic house paint for some jobs but it doesn’t cover well, I also use One shot you can paint alot of polystyrene with very little One shot and it covers well.

This was done in polystyrene with gold one shot I used 2 small tins and it 3m high

this one is bigger still and was painted with acrylic latex

and this was also painted with acrylic paint and one shot on the letters if I remember right, and you can see the size compared to my dogs 🙂

Many people who come in the shop think styrofoam (polystyrene) is the same as Signfoam or other HDU products….but they are totally different in all ways.

[Robert Lambie]

cheers for that henry. very impressive stuff mate.
do you get much call this kind of work or is it only once in a blue moon.
you seem to do lots of specialised work. one offs sorta thing..
are you just left to it.. i mean to come up with the sign from scratch or is it all to spec? when i get something to do from scratch im always please when completing it.. very awarding in itself 😉

[John Singh]

Great to see this work Henry

John