Wood Material for the flowbench

[77-1212596771]

After checking some threads, which picks a bit on this topic, I would like to start a thread which mainly is focussed on the different kind of woods to used on the flowbench.

Good Material:
When I understand it right, quite optimal for high pressure flow benches a very thick ( 1" ) MDF laminate plate, which eventually also has a plastic film laminate on top is quite perfect for the job.

Bad Material:
Worst material is particleboard, which is made of crumbs of wood flakes. This material is cheap, but missed mechanical and pressure stability and should not be used.

To Discuss:
"Glulam":
What about thick glulam ? This is real wood, glued together and then sewn to the customers sizes.
From the mechanical perspective, this material is very stable and just a bit more expensive than plywood.
Often its also available in in thick sizes (2 " and more).

"combined core glulam-plywood"
I am not sure how this stuff is called in english spoken countries. It does have a core of glued real wood plates and on top and botton you have one or two MDF lamination.
(seen only sizes up to 1 1/2 " in Germany)


Any comments on this ?

---------------------------------------------------

Wood types in comparison:

At the typical diy home improvement shops I saw following wood types:
Birch
Pine
Spruce
Beech

Which pro and cons do you see with these wood types in the flow bench environment ?

Thanks,

Daniel

[106-1194218389]

Daniel,
I used Melamine from HomeDepot. It does have a wood product that looks similar to particle board, but to me looks denser and the glue looks better than regular MDF and is also quite a bit stiffer. It is also covered with the white covering that is a laminate of some kind that seems fairly sturdy to me. I really liked it. It was $28 USD per 49"X96"X3/4" sheet. It saved me the time and trouble of painting and gives a better surface IMO than paint. The only trouble is you had better like white
John

[77-1212596771]

John,

I think I know what material you mean. They are often used in wet/bath rooms.
However you still have to paint the edges which you have cutted - right ?

Daniel

[bruce]

I'm "sold" on the MDF myself. It's messy to work with as in dust all over the place and you NEED to wear a respirator when you cut it or you have a cough for months afterwards (ask me how I know, my cough finally stopped the other month). Next bench I build I'm subbing out the cutting to a shop that has the equipment.

My bench is quiet, I think the density of the MDF helps a lot with the noise. My wife even commented on the low level of noise with 4 blowers running.

[Tony]

What you can get, and the type of trees (and glue) it is actually made from, probably varies in different parts of the world. At least in Australia, my take on this is as follows:

MDF, very dense strong and heavy. Easy to work with but fairly expensive. It can be coated with cleat estapol, marine varnish, or painted inside to prevent any very slight air leakage through the material. Pretty good stuff, what I am using now, and definitely what I will use from now on.

Particle board. Made from fairly large wood flakes, lighter, not as strong, and leaks air like a sieve. It has no advantages except for low cost. Not recommended.

Melamine, which is the white coated particle board used in modular kitchen cupboards, bathrooms, laundries, and similar places.. It uses even larger and rougher wood flakes than even normal general purpose particle board, it is therefore fairly weak. But the extremely hard wearing and flat surface makes it ideal for some non structural flow bench applications.

I have a melamine bulkhead within my bench that does not have to resist much differential air pressure. My rotating orifice turret disc slides on this smooth hard flat surface leak free. Melamine is ideal for that type of application, but is probably not strong enough to build the whole of the pressure bearing outer structure.

Thick marine plywood. Probably the best and strongest material of all ?
But I have never actually tried it myself.

[77-1212596771]

Any thoughts on "glued wood" / glulam ?

Daniel

[Tony]

I have never heard of glulam?
Although we probably do have something very similar in Australia but known here by a very different name. Any chance of a picture ?

[106-1194218389]

Tony,
That info was very good thanks. In the HomeDepot by me the melamine looked to be a much better quality and was stiffer than the "particle board" they had there. The Melamine did in fact have much larger particle than the other but seemed to be glued better. I do not know if the other stuff was "particle" or MDF but seemed much finer and seemed like it would have been better but when I looked at the stuff they had it seemed sort of deficient in the way it was glued. The stack had many corners blown off and edges roughed up and that was one big reason I went with the melamine. I haven't started the Motor box yet so I will check around for a good quality MDF. The surface of the melamine I have is pretty tough and impresses me. And Daniel, I do not have any edges exposed to air pressure so I have not painted the edges yet, but it would make it look nicer. They actually make a melamine strip you can cut and glue on the edges so it would look really nice. (Of course I guess you could use some really nice cabinet grade cherry plywood)

John :;):

[77-1212596771]

[Tony]

The melamine I have seen here in Australia is pretty poor quality crumbly stuff inside. It looks fine on the outside, with the hard white covering, but when you saw it, the cut edges look horrible and powdery. I would not trust a wood screw into the edge of that stuff, but it would probably be o/k bolted or screwed through from side to side.

A cabinet maker or large timber merchant should have a melamine edge banding machine. They can cut panels to exact size for you, exactly square, and then hot glue a narrow strip all the way around the edges. That is how they make kitchen shelves, and they have the precision automatic machinery to do an absolutely perfect job of this in just a few seconds.

[Tony]

Ah Daniel, now I know exactly what you mean. That looks extremely strong, but it may be rather heavy and bulky.

My own preference is for a welded steel angle frame, with MDF bolted onto the outside. This makes preventing air leakage at the corners very easy. Even with accurately cut panels, the corners are usually the most difficult places to completely seal. My metal working skills are much better than my success with timber. All wood seems to hate me.

[larrycavan]

Since you're saving thousands and thousands of dollars over a commercial bench, IMO, get top grade, 3/4" plywood and be done with it. It's all for nothing if the cabinet can't cut the mustard. There's a time to be conservative, a time to be down right cheap and a time to spend what it takes to do the job properly. Building a machine that could potentially last a lifetime is an occasion to spend what it takes for such a piece of equipment. Top it off with some good epoxy paint and you have a fine piece of machinery.


JMO

Larry C



Edited By larrycavan on 1217739582

[bruce]

Larry well said!

With the amount of money one can save on building a flowbench for themselves why cut more corners by trying to go "cheap"? ???

[106-1194218389]

[106-1194218389]

While we are on the subject of plywood, remember all plywoods are not created equal. Here is a good site that gives a quick explanation of the different grades of plywood and their uses.