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Methanol to Aid in Drying a Transom

Hi:

I have a rotten transom that I have decided to treat with hardener in an attempt to add strength. On researching this topic, it appears this type of repair can have varying levels of success. It does seem however, the chances of success are greatly increased if the transom can be dried out really well.

For this job I cut the cap off the fibreglass transom cap to exposed the top of the wood transom core. I then a drilled a bunch of long 3/8 holes down the length of the transom. I set a radiant heater at the back of the boat directed at the transom and am getting it nice and hot: about 80 degC. I then ran my air hose with a chuck and long tubing inserted right down to the bottom of those holes. I have the air set to run at a reasonable purge. The compressor (40 gallon) is cycling every 20-30 minutes. The air is coming back warm and moist which is great. I'm going to do this for at least another week.

I was talking with my dad today and he suggested pouring methyl hydrate down the holes.

Has anyone ever tried this before?
 
??----The methyl hydrate would absorb the water.----Then you still have to get the methyl hydrate and the water out.
 
Wow, you scare the crap outta me with your thread title.
Years ago I ran some older generation Rolls Royce engines, 2100 shaft HP. On hot days, we ran them “wet” to obtain full power during takeoff. This was done by injecting a mixture of water/methanol into the burners. Water cooled the air charge, (giving density back), methanol allowed the water to “burn”.
I still remember the warning, CAUTION Methanol is a Virulent Poison.
if you ingest less than an ounce, you die. If spilled on skin, it penetrates, & you die. If you inhale it, you die. Best case scenario is your optic nerve rots, & you’re blind.
Then I saw methyl hydrate. Thank Christ.
Do you have access to oxy/acetylene welding? If so, your license probably allows you to get a tank of nitrogen, same stuff Costco puts in your tires, It’s great, actually incredible, for displacing moisture. You’d have to have a regulator, & makeup some small lines to slowly bleed it into the bottom of the transom.
Dont do it in an enclosed area, a couple breaths will displace moisture & O2 in your lungs.
 
Super interesting. I actually have a bottle of nitrogen and a regulator that I can get rigged up right away. I'll get it going and report back.

Thanks!!
 
I just re-read your OP. The problem with using your compressor is the air is not dried, notice how much moisture comes out when you purge the tank each day...you do purge it, right?
N is not super light, it’s close to normal “air”, so it won’t dissipate upwards as quickly as say helium or even propane.
I would have lots of holes drilled, to near the bottom of your transom.
You don’t need blasts of N, just a trickle, & it will move liquid or water vapour easier than ice.
Its used in tires not so much as it doesn’t change pressure with temperature,(it does), but it keeps moisture out, so you don’t get frost crystals & leaks in really cold weather, & prevents combustion on jet tires in case of hit brakes.
They use lots of it in the oil/gas industry, displaces moisture & prevents corrosion in empty pipes/vessels, along with lessening explosion hazard. We have onboard N generators that fill the jet fuel tanks as they’re emptied.
 
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Just vacuum bag it and let the pump run a while....vacuum is one of your best friends for removing moisture...
 
Just vacuum bag it and let the pump run a while....vacuum is one of your best friends for removing moisture...
Yes, that is true. Besides checking for leaks vacuuming down is THE reason they do it with your air conditioning unit in the car to remove all moisture.
The science behind it is that as pressure decreases, the boiling point also decreases.
If you reduce the pressure the water will boil at room temperature therefore evaporate out.
remember the grade 10 chemistry experiments where you can put your hand into a cup of boiling water as long as the pressure was low?
if you have access to a vacuum pump, can things up, and you don’t have a huge void between the outer and inner skin, (which may very well collapse the two panels),that is certainly a good idea. To be really effective you need a pump and system that can hold vacuum like an air conditioning service pump.
 
Hi. Thanks for your reply's. Unfortunately my nitrogen tank was nearly empty, so that didn't happen. I also don't have access to any sort of vacuum stuff.

I've been worried about letting the temperature get too high and I've been keeping the transom at around 85C at most. What if I let it get to 105C or something. Get it above boiling point. Is there a risk of some sort, maybe warping the fibreglass or something?

Thanks again.
 
I've a YouTube where holes were drilled down into the transom and from the outside of the transom about 3/4's of the way thru the thickness of the transom. Denatured alcohol was poured into the holes from the top and allowed to run out the holes from the outside. Alcohol absorbs water and thus flushes and it dries much faster than water. MUST use in a very well ventilated area. Only use a little at at time and catch the runoff.
 
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