Fruits Of My Labor (A-113)

[Tony G]

Thank you Larry.

Jerry, we are attempting to prebend two 1/8" sheets for the total thickness of 1/4". It only held about 45 degrees when I released the clamps. So it looks like another round of water is in order. This time I won't be quite so conservative now that I've seen the results of lastnights trials.

Ebb, it is resiliant! I buy baltic birch because that is the only thing offered out here in the middle of no where. I introduced an extra 3 degrees to compensate for any spring back...yeah, right.

[Tony G]

Because it isn't feasable to keep a decent temperature 24hrs a day with the little 5KW heater we have, I've been trying to think of ways to at least get the chance to glue small peices together. Some of the small electrical heaters still use 750 to 1500 KW and that's a lot of juice for what you get. So I got a couple of sheets of 1 1/2" styrofoam and cobbled together a "hot box" that is 36"w x 48"l x 30"h. The corners are pinned together with 1/8" x 18" rods which makes it easy to put together and pull apart. It is heated with two 100w bulbs in reflectors. I don't have a thermometer handy but it was nice and toasty in there this morning while the ambient air temp in the shop was near the mid thirties. (outside temp was 14)


I still have to come up with a way to heat the hull and cabin this winter if I want to lay down some epoxy. It may be just a different version of this as I don't want to invest in a bunch of heaters. I can heat up the outside of the hull by directing the gas heater toward it for a short while as we bring the shop up to temp before going to all electric heat. Then it may be up to some more reflectors and a means of clamping them in place for twelve hours. I've even thought about getting some electric blankets and draping them over the hull adjacent to where we're working to see if they could hold a constant temperature. Any ideas out there?

[Commander 147]

Tony

It is rare that I need to heat my work area for Destiny most of the time my problem is that it is so hot I can hardly breath let alone work and the epoxy kicks much faster than I want it to, but I have had a couple freezing nights since I started this project and I may get a couple more soon. But heat lamps directed onto the raw epoxy was enough to make it kick properly even though it frooze overnight. My shelter has no way to heat it since it is open on both ends. You are enclosed and insulated so work on the inside of your boat might work out with just the heat lamps like I used. 1976 was the last year I lived in the cold county so I have probably forgot a lot of the pain involved in working in that enviroment but you asked for suggestions so............

[larry]

Tony,
We had an extreme winter here last year and my girl wasn't inside. I was able to maintain a good temperature inside by just wrapping her good and tight with tarps. I was really surprised what heat I absorbed from the sun this way, even with snow on top. I had one small heater and a type of brooder bulb I use to keep my chickens warm. At freezing temps it would be 65 degrees by 9:00am. Under twenty and/or the wind blowing I didn't even try though. At 14 that certainly is a challenge when trying to spare expense. But being at 30 in the shop you should be able to get the inside cabin warm.
Stopping escaping heat will benefit mostly I think, and closing off the berth and access to other areas where your not working whereby minimizing the space.
Your right the tiki says it all.

[mbd]

... Any ideas out there?

Move South?

I'm still trying to get over the shock that you tore out your previous gorgeous and curvy interior...

On the constructive side of things, I don't know about exterior hull work, but perhaps, if you're planning on it, you could make insulating the interior your first order of business, then keep it nice and toasty inside?

[Tony G]

Stopping escaping heat will benefit mostly I think, and closing off the berth and access to other areas where your not working whereby minimizing the space.

I tried to do a multiple quote reply because all three of you hit the nail on the head. "Move South"! For some reason I never thought of just sealing off the area we're working in. This deserves a closer look to find out what kind of impact just filling in those big holes would make. I think we may need the assistance of a low/high temperature recording thermometer. I wonder if it will be necessary to insulate the hull? Would it be better to insulate the outside vs. the inside of the hull? My reasoning is, will the cold hull "wick" the heat away if just the inside is insulated? Will I have to heat both sides? I could use heat lamps on the outside directed at the hull but eventually I'm going to have so many lights burning I may have been better off to get another energy hungry heater...

It looks like progress may take a back seat to investigation for a bit here as the cold weather hasn't really hit yet. Even though it is bright and sunny this morning it is only 1 degree above zero! I'm confident the hot box is doing just fine but the shop is going to be cold and we're going to burn through some gas today!

[Commander 147]

Tony

You might be surprised on how little it takes to keep the inside of the boat toasty warm. Blankets over open hatches or uninstalled ports would probably be all it takes if you use heat lamps directed on the work. I've been overnighting on my boat in some pretty chilly conditions and body heat was enough to keep her comfortable inside.

[ebb]

this is your gallery spot - I have no quams and would not be angry in the slightest if you wanted this ebb stuff, any of it, removed, which I can do from here, OK? Really.]
You want to see what temp your glue/epoxy will set up at.
Could do tests by gluing two small pieces of plywood together at right angles and see what happens with them in various cold locations in your shop. and boat.
I'd try setting up something on the workbench with elcheapo aluminum/clamp worklights (100W incandescent.)
While epoxy can be gummy for awhile (and you think you've screwed up) at low temp it will eventually set up.
I have always assumed that 'all' 2-part bisphenol epoxies will eventually cure - whether the work was done at 50 degrees or 100 degrees.
However that may be just the experience I have with my stuff in the non extreme temps of mid-coastal Calif.
Most material data sheets will give the maker's safe application temp range - which could probably be stretched a little. Experiment.

With inside/outside heat & cold you could have moisture (dew) settling on your work. That could mess with your bond.

Guess that actual jobs you do on the boat will be locallized.
Not overall priming/paint jobs. They might be safer to schedule when it's warmer, and the doors can be open.
Setting up lamps close, but not too close, to a glue-up on the boat can easily be done.
I use cheap lite polyester quilted pads - that have found a number of non-furniture-moving uses on the boat.* Casually drape/tuck one of these over the lamps but not touching the lamps and when you come back in the AM the epoxy will be hard.

Could drape an electric blanket on the outside of the hull where the work is inside.
Cover that with a quilted pad and prop them close to the hull. No problema, senor.

Halogen worklights produce a tremendous amount of heat.**
Not so sure they can safely be tented over with cloth and left alone.
Sears/OSH halogens I've used are too hi-temp aggresive imco. A few of the old-fashioned worklights (purchased new so their wire connections won't become an issue) will be safer to tent over an epoxy job.
After burning myself a bunch of times I've 86ed halogens from the boat and now use flourescent work lights. Which tend to be bigger and even more clumsy then I am. !*%^@$*?.. cords!
In fact when dropping the halogen worklights had the stupid poisonous bulbs break making it too big a frickin deal to change the bulb out - so trashed them.

I don't think it's too big a deal to get the epoxy to cure.
If you are not already: use only 100% solids epoxy in your shop. 100% solids means no solvents. Less chance of blushing with slow hardeners.
Cold conditions will cause epoxy to blush. I never use West Systems. Non blushing epoxies can be purchased
- but attention to your tenting procedure, getting the right amount of heat for setting the epoxy up, is probably easier than you think.
A large-dial outdoor thermometer can be propped close to the glue-up. Santa maybe will drop a little digital one in your stocking over the fireplace.
[I always cleanup with denatured alcohol (and may be paying an ugly price for doing that). I tend to clean up the job before leaving so that there is minimum sanding/scraping prep when I come back for my reward. It is imco the least lethal of available solvents. Maybe there's a non-explosive cleaner to use by now. I wouldn't use water/vinegar, since epoxy is alkali, vinegar acid, and water soaks. There may be a citrus product, but needs research.]

But you scare me when you talk of buttoning up your workspace, you want 'fresh air' to work in. There is probably enough in the shop - BUT
I would especially be wary of solvents that can flash (obviously alcohol as well) - and fumes that can kill.
__________________________________________________ __________________________________________________ ______________
*Quilted Protective Pads. (McMasterCarr, Cat Pg 1272) The ones I have are the lite weight cheaper ones, about 6'X6' and 8'X8'. Stuffed with something polyester-wool, they don't attract moisture and dry quick. Originally got a bunch, cut them in half and drapped them from the toerail around the whole boat when the awlgrip topsides were new.
But now I fold them to make a soft seat, to kneel on, to lay on (zzzz z z ), to put non-scratchable work on like the cabin windows, and to tent a localized glue-up with lamps under. Certainly can consider these as 'insulating' also. Always a couple floating around in the back of the truck.
__________________________________________________ __________________________________________________ ______________
**If you tent the boat wanting to come back to a warmer boat interior, halogen worklights (smaller ones with clamps) left on all night as space heaters might be cheaper to use than an allnight heater. Safer???

[Tony G]

Well here's what I'm trying first. I rolled out to the box stores today and picked up a couple of cheapo digital min/max/current thermometers and one big dial thermo. The dial one is for the shop so I know the temp in house. One of the min/max thermos went into the hot box. With two 100watt bulbs running in there and a shop temp of 55deg the box temp was 92! Warm enough.

I also picked up a sheet of foil backed 3/4" styro and cut filer pieces for the four ports in the cabin, one for the main bulkhead, a piece to fill the opening from under the cockpit and one that covers the main hatchway. I put 3 more reflectors with a 100 watt bulb in each securely clamped in the main cabin and closed her up. After about 45 minutes we were up to 60 degrees. I will swing by the shop tomorrow before work and note the max and min temps. Fingers crossed.

[Commander227]

Tony,
how about the heat cable for roofs and gutters. you could tape it in zigzags to the outside of the hull and cover it with Ebb's moving blankets. It would be like having in floor heat, and little worries of explosions.
Mike

[Tony G]

Well here are the preliminary shake outs. The shop stays "relatively" warm overnight if I go there for a couple of hours after work consiering the outside temps. The ambient shop temp was 45 degrees at 7:15 a.m. with the outdoor temp down around 17. The hot box was 69 degrees, which was the 24 hr. low temp., with just one light burning overnight. So the hot box will work for gluing or coating or what have you. It appears the limiting factor is going to be it's limited volume and in response we will have to make a racking system that glue and epoxy doesn't like.

The boat was a bit different though. With three 100 watt bulbs going over night the high temp was 60 degrees at the level of the side deck turn-out from the cabin trunk. That was the temp when I left her the previous night in a pre-heatd shop. The low temp recorded, and the temp I found the following morning was 52. Not good enough. So I fashioned a stable stand and adjusted all three reflectors to shine on an area of approximately 2' x 3' of the hull and set the thermometer slighly off center of the "hot spot". The following evening the shop's air temp was close to 50 degrees (outside temp of nearly the same!) and the thermometer's low recorded, high recorded and present temp was 79 degrees. That would work. One problem I see is fashioning a stand that will allow the reflectors to be aimed with the propper orientation.

Tony,
how about the heat cable for roofs and gutters. you could tape it in zigzags to the outside of the hull and cover it with Ebb's moving blankets. It would be like having in floor heat, and little worries of explosions.
Mike

I really like this idea, Mike. I had completely over looked the concept. You saw the Moorhead store when you picked up the Ensign hull. That building taught me a lot about winter water pipe "maintenace". I had also used heat tape and a variable rheostat in one zone of our reptile room for an under-tank heat source. Coming up with a way to hold the tape against the hull is important as contact is necessary and the heat will probably over power the tape's adhesive. I keep going back to the idea of gluing it to a blanket of insulation and then tying or strapping that to the hull. But the more I look at he curves in that area it would take quite a network of lines to hold it in place. And I can't overlook the fact that there is a good deal of cost involved to build it. Ok, less than $200 but that will buy a lot of light bulbs! But there is a certain "elegance" to your idea and I keep weighing the results of my light/thermo tests against the heat tape idea.

As an aside- I was completely baffled and thuroughly disgusted that the second curved plywood corner came out of the form nearly flat! WT... I certainly had checked the flex direction before cutting the flat stock and had that right. I double checked the off-cuts and verified that the orientaion was correct. But it was just flat out stubborn. It wasn't until I held the two pieces side by side that I noticed that they were two different products. Both were sold as 1/8" Baltic birch plywood but one had face veneers that were twice as, if not three times as, thick as the other. Crap. So hopefully Black Friday will find me at Valley Hardwood with the correct stock in hand. I just hope he doesn't have a stack of super thick veneer sheets.

Hey, have a wonderful Thanksgiving all!

[ebb]

1/8" ply you have to bend, if bending is possible, WITH the face grains.

You may have to cut into the compressed side of the ply with your table saw. Like cut with the grain 1/16" in on the side that will be on the inside of the curve. The tighter the curve the more slices you must make. Like 1/2" spaced cuts.

If you are encapsulating, which I would heartily recommend, you will gain 90% of the plywood's strength back.

With tight curves you may still have to presoak the ply in boiling water to get it close to keeping bent.
Don't know about keeping its curve.

To keep the curve you may have to augment your jig.
Use mylar or seran wrap to separate the pipe form from the work. Epoxy the cut side
On your second or third try you might be adding strips of glass over the curve INSIDE. It would be a composite you are making.
All in an attempt to keep the wood from spring back.

Good luck.

Be easier with plain 1/16" veneers (Constantines). Ending inside with an added layer ie a piece of 10oz cloth.


You saw my cheat. I glued afro mahogany veneer right onto PVC pipe. Wish now I had used drain pipe rather than sched 20.
But the choice of diameters would have been limited.

For bigger curves you can get ready-made curves out of poplar - they come in quarters and halves. And the stuff is thick.
Poplar has the same rot resistance as birch, so it has to be totally isolated from reality.

[Tony G]

Hey Ebb

I tried doing 1/16" deep kerf cuts every 1/4" on a what if mission in addition to steaming with the iron. It ended up with a sharp (8 degreeish) bend every quarter inch through the radius. Sure it could have been filled and sanded to work but it was a disappointing result for the amount of additional work that was put into this piece when compared to the other piece that came out of the form smooooth and shapely.

You used PVC? I didn't know that. I***assumed*** you either laminated your own or bought them ready made. I found a source for quarter round, 2" radius, 1/4" thick stock but the minimum order and shipping would have kept me in quarter round and full debt for a year or two :0

[ebb]

Another couple cheats: One is wigglewood. Fully stocked lumber stores. Concrete guys use it to make forms for curvey walls. The ply is all one direction no cross veneers, uni-direction layers are glued to unwoven cloth scrim, easy to form any linear curve. Meant for forming, not to include in a composite.

Incorporated a cardboard mailing tube for a radius right angle corner on the 1/4" plywood cupboard front in the galley. [pix @ ebb's PGT/pg17/#336]
It was 'easy' to glue the paper tube to the 90 degree front & side connecting the pieces.
BUT first the setback ply edges were feathered inside to the tube's diameter
which made a pretty good curved surface in those edges to glue the tube onto. Turned out this feathering for a 3"D circle on 1/4" ply is about 3/4" wide, coming to a sharp edge. The cardboard radius, the tube, is epoxied to the inside of the ply panels. Think that's important.
Glued that way, the cardboard appears to be on the same plane as the outside ply surface. Not obvious what material makes the fancy corner.

So, a WHOLE 3"D white USPS mailing tube - including plastic endcap inserts - was used to glue the prepared ply pieces together to make up this OHSO upscale radius corner (insert end caps make the paper tube quite stiff.)
After cure, cut off top, bottom and sliced away the whole inside unglued portion - which was at least 66% of the tube. It's called: 'cutting corners.'
Voila!...round cardboard corner. (Careful! It's a bit limp at this point.)

SHOCKING!!!, you call this fine woodworking?

The corner outside has no visible seams after sealing and priming.
However, the unseen 'inside' of the glue-up has two or three overlapping glass pieces laminated around the corner for strength - tieing it together, beefing up and stiffening the cardboard. The whole thing is saturated and encapsulated epoxy and cloth.....and cardboard.
It seems to have worked well enough to make me think that the method could be used on exterior fiberglass projects - if the weather-side of the panel also had a layer of cloth & epoxy - instrument covers, dorades, vents, even small hatches. I left this interior piece well sealed but one sided in way of fiberglass.

Still haven't installed the cupboard front with its short side piece and nice but rather thin corner (when you look at it edge on.). It's stiff and doesn't bend or flop. It's been in and out of the boat and truck a number of times. That fake corner hangs in there - plenty opportunity to have torn it off already - nope! Knock-on-wood.
There is NO movement, springback or change in radius on this cheap shot. It might as well be solid wood......but why?
(Tony, it certainly seems like I'm a paper tiger beating his chest here. Sorry. Had to point out that cheating is a fact of cabinet making.)
__________________________________________________ __________________________________________________ _______________
OnlineMetals ships stuff in thick/heavy cardboard tubes which I've used pieces of for forms. But those tubes are way too thick for even thinned epoxy to penetrate and soak.
This Gov'mint issue thinwall cardboard tube material transforms into another animal when it's absorbed epoxy juice. And shelled with glass cloth.

[Tony G]

Ingenuity, man, ingenuity! Hulls were once made of wood. Then all plastic models proved themself. Why not a plactic corner? Who really cares what the mold was made of! You're still at the top of my list, Ebb.