New to this and need advice please

[Bammer]

Hi all....
I am new this this as well and I am sorry if I am asking a question that may have already been answered ...but... can you explain what "stabilising" actually does and how long do you leave things under vacuum for ?

The basic principle of wood stabilizing is to take a piece of soft or punky wood and inject it with resin to create a stable, hardened wood blank that is safe to turn. The resin displaces air pockets throughout the grain structure, creating a dense blank that is nearly impervious to moisture changes and can be polished to a high gloss.

How long to vacuum ? Good question. Some people advocate over night. But the easiest way to figure is until it stops producing bubbles. I usually let it soak under vacuum till I'm ready to cook it.

As for using the vacuum to degass resin, can be a very messy job. The process of sucking the bubbles out causes the resin to bubble up all over the sides of the mold. and when you release you may find you don't have a full mold anymore.

PR does not need a pressure pot or vacuum to cast in.

Epoxy will depend on how quick it set time is (not cure time). Again it's preferred to use a pressure pot with this especially for pen blanks.

Alumilite clear does need a pressure pot. You only got around 7 minutes I think before it starts to cure.

 

[Bucks]

Pretty good explanation Brad

 

[jackjohnsonuk]

Does having a pressure pot negate the minimum temperature requirement of these resins? I work in an unheated shed and am anxious this might be a problem.

 

[Bucks]

Does having a pressure pot negate the minimum temperature requirement of these resins? I work in an unheated shed and am anxious this might be a problem.

Sorry Jack, but no you still need the same warm dry conditions

 

[jackjohnsonuk]

Getting my wife to let me agree to spend money on my little projects is one thing - being allowed to bring them in the house is another - perhaps I might just have to stick to buying my resin blanks after all.

Thanks for all the advice I've gotten from everyone on this thread, and all the other threads in this section - extremely interesting.

 

[DaveP]

Does having a pressure pot negate the minimum temperature requirement of these resins? I work in an unheated shed and am anxious this might be a problem.

There are a few solutions that may help...

1. Some of that heat insulating / reflecting stuff that's used normally used behind radiators to wrap the pot (or maybe make a polystyrene box), added with .........
2. A heat pad that's normally used in a vivarium, or..........
3.A heated seed propagator.

P.S 2 or 3 go under the pot... not inside

 

[jackjohnsonuk]

Thanks Dave, all sound possible - I mean the whole workshop is insulated with 50 PIR, so is reasonably well insulated (I do still need to do something about the single glazed crappy perspex window though), but I only run the heater in there when/if we get below 0 - I could do a combination of 1 and 2 I guess. Building a box out of insluation board and sticking a heat pad in there wouldn't be too difficult or expensive at all.

Thanks for the tips!

 

[Bammer]

Does having a pressure pot negate the minimum temperature requirement of these resins? I work in an unheated shed and am anxious this might be a problem.

Moisture is not your friend. I don't mean stuff being wet, I mean moisture in the air, airline, in your pot, on your mold etc.

 

[jackjohnsonuk]

Moisture is not your friend. I don't mean stuff being wet, I mean moisture in the air, airline, in your pot, on your mold etc.

I have a moisture trap I use when spraying so can implement that to keep air out of the line into the pressure pot. Any tips on fixing any of the others within my constraints?

 

[Frederick]

Hello Jack

What you must be careful of here is the cover of the vacuum chamber. Stabilisation of wood requires a very high vacuum over a considerable amount of time, sometimes hours. Degassing of resins etc does not take that long. I have heard of chamber pot lids breaking and shattering under atmospheric pressure. I have a small 6 inch vacuum vessel and the lid has to be half an inch thick and made of plate glass. I would recommend buying a vessel that has been specially designed for the purposes of stabilisation and can withstand a minimum of 29 inches of mercury for at least a few hours.

Also the vacuum guage is fixed to the bottom of the vacuum chamber on the one shown which, in my opinion only, is not a good idea as stabilisation fluid could be sucked into the pump easily. I think it better if the guage is attached to the glass lid.

Metal Clay sell some good chambers especially for this purpose. Unfortunately these are not cheap. I am no expert but have now made many wooden pen blanks most of which have been stabilised, dyed or both

Cheers
Frederick.