Discussion on what materials to build speakers out of

[sq225917]

has anyone ever used epoxy impregnated wood.

vacuum bag the wood with the air drain at the top and pre mixed low viscosity resin in the bottom,then heat it and suck the air out.

the epoxy gets drawn into the wood and sets, removing voids and giving a rock-solid material.

[planet10]

Originally posted by sq225917
has anyone ever used epoxy impregnated wood.

vacuum bag the wood with the air drain at the top and pre mixed low viscosity resin in the bottom,then heat it and suck the air out.

the epoxy gets drawn into the wood and sets, removing voids and giving a rock-solid material.

I have not done it... i have been thinking about it for years. One of my clients is giving it a go as we speak. He is building a curvy bruce out of barrel staved 1 1/2" (38mm) red cedar impregnated with polyurethane. The pieces will be soaked in a thin mixture... the way the liquid is sucked into the cedar shouls create a very complex transistion zone between no resin and lots which should create some very interesting properties.




Jonathan Carr (Lyra) suggestted in a thread on the same topic taking it a step further and laminating a sheet of fiverglass or kevlar closth to the panel.

dave

[peterbrorsson]

The wood is well dried and stable I have had it stored in my house for approximately ten years.My house is stable year round at aproximatwely 38% humidity.

Hi SCD!
Well, there you are. The problem with todays drying technique is that wood is processed and dried in 3-4 days. This is what we get in Baumaxx, Bauhaus and what else supermarkets for DIY here in Europe. I bet the situation is not better "overthere".
If the people controlling the drying process are skilled then there are no problems. But as always, faster means more care and precision.

I had a 100 year old house in Sweden in which I knocked down a wall. It was built of two inches thick, 100 year old pine. The boards were 10 times harder than the gene manupilated, fast growing Pine that are planted in Sweden today. Of course time makes it harder but the forests are not the same today as before.

Hmm, 25 Year rings/inch. Were talking high altitude growth/climate zone 5-6?

Nice speakers you have there!

Best regards
Peter

[planet10]

Originally posted by peterbrorsson
Were talking high altitude growth/climate zone 5-6?

I had the opportunity to help mill some fir similar to Scotts... {http://www.urbanmilling.com/}

In my case it had been logged in 190x and for some reason left to sit in the forest until the next time they clear-cut. They were in the way so they dropped them off in an ecoWoodlot right in the middle of the clear-cut. Once the outside was cut away the wood was fantastic.

Vancouver Island doesn't really have any extreme altitudes (it is thou the top of a mountai range sticking out of the pacific ocean with all the attendant fiords & such).

dave

[planet10]

According to this map i googled up (and tweaked) Vancouver Island is mostly zone 8 with some 7 & 9. Scott's wood would have almost certainly been local (and could easily have been harvested and milled within site of the bridge it made).

dave

[planet10]

Originally posted by planet10
Vancouver Island doesn't really have any extreme altitudes (it is thou the top of a mountai range sticking out of the pacific ocean with all the attendant fiords & such).

Highest peak is not quite 2.2 km (http://www.peakbagger.com/range.aspx?rid=1203). Attached is a snapshot from Google Earth -- i expect that this peak is in the snowy part and that Scott's wood came from near where he lives which is on the cost above the snowy peaks right to the left of where the water starts opening up.

My place has the pushpin and my chunk of wood came from right across the fiord below me on the map. (probably 400-600 m elevation -- i'm at about 245m on the side of Mount Finlayson, and the fiord is called Finlayson Arm)

dave

[peterbrorsson]

Hi Dave!
It does not have to be high altitude. It depends also on the climate. That's why I put / in the question.
I come from the "south" of Sweden, relatively speaking, where the pine is growing in sand soil. This is also a highland plateau. Veeryy slow growth, beautiful and easy to stain!

The South European pine is just awful if one gets lowland pine. I have seen examples in my work with 1 cm summer wood!
High altitude on a North slope is another matter.

[peterbrorsson]

Oh, sorry I should have mentioned that I've got no experience of Douglas fir. So growth rate unknown to me.
Cheers
Peter

[peterbrorsson]

My place has the pushpin and my chunk of wood came from right across the fiord below me on the map. (probably 400-600 m elevation -- i'm at about 245m on the side of Mount Finlayson, and the fiord is called Finlayson Arm)

4-600 m is ideal for pine anyway. Still get some lenght combined with slow growth, voila excellent wood.
Looking at gle.earth image, I MISS THE SEA!

Cheers
Peter

[planet10]

Originally posted by peterbrorsson
4-600 m is ideal for pine anyway.

I recently found out that douglas fir is actually a pine (as i've known that yellow cedar is not a cedar)

dave