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J.Madison
08-06-2014, 11:09 PM
Or drafting ducks, or whales, or whatever you want to call them.

I'm designing the Next Greatest Boat Ever and have been struggling with cans of beans, candlesticks, and other such devices holding my battens in place. Time for some real spline weights.

First step was to carve a pattern. I cut mine out on the bandsaw by eye, then got it close to its shape with a 36 grit disk on a 4" grinder. Wicked tool. I didn't use any pattern or plans or anything. In the end it could have used a touch more draft to make it easier to remove from the mold.
http://i1123.photobucket.com/albums/l545/JMadison1/Spline%20Weights/CastingDucks002_zps6ef78247.jpg

I used some course paving sand I had on hand and added about a 5-10% mixture of clay cat litter to help it bind. I didn't notice any real benefit or harm from that. With finer sand it probably would have helped. Its scary adding water to the sand to get it to hold a shape, but a fair amount of water is necessary.

http://i1123.photobucket.com/albums/l545/JMadison1/Spline%20Weights/CastingDucks005_zps2e49f73f.jpg

A screw in the bottom of that pattern assisted with removal after packing the sand around the pattern.

http://i1123.photobucket.com/albums/l545/JMadison1/Spline%20Weights/CastingDucks007_zps55d9c850.jpg

I have lots of scrap lead from pouring the ballast keel on the Maid. The pot is from the thrift shop. It nearly survived the event. A strong handle is the number one requirement for a melting pot.

This weed burner will melt a whole pot in about 30 seconds. Pretty amazing to watch.
http://i1123.photobucket.com/albums/l545/JMadison1/Spline%20Weights/CastingDucks011_zps6803275d.jpg

The neighbors are pretty sure I cook meth now.

Here the wife hides behind the truck. I admit that all the water in the sand had me nervous. I tried to dry it out with the torch before pouring but that didn't do much. In the end the sand is porous enough that the steam can escape through it. No problem at all. Don't get it too wet though!

http://i1123.photobucket.com/albums/l545/JMadison1/Spline%20Weights/CastingDucks014_zpse9efe54d.jpg

http://i1123.photobucket.com/albums/l545/JMadison1/Spline%20Weights/CastingDucks020_zps18fa643f.jpg

I eventually learned not to overfill them, but leave them clean like this. It is easier to remelt and recast ones that have defects rather than try to fix overflow with a chisel or anything like that.

-Continued...

J.Madison
08-06-2014, 11:39 PM
A days worth of casting: 12 ducks, and a couple blocks to consolidate the rest of that scrap bucket. At this point everything is very rough, due to the sand I used. A wire brush removed the sand that stuck. Any extra bad warts were cut off with a chisel.

http://i1123.photobucket.com/albums/l545/JMadison1/Spline%20Weights/CastingDucks022_zps66a435bf.jpg

Here there are some gaps in my photography. Each duck was drilled for the hook. Don't even think about using a drill press unless it will crawl along at 60 rpm. Lubrication is a must. I've heard soapy water and acetone both work well. I dipped the bit in WD-40 before each hole and stopped breaking bits after that.

The hooks are made from bronze ringed boat nails driven in solid and bent over at the vice. Then the heads were cut off. I sprayed on about 5 coats of a high build spray paint. This worked very well. Most of the low spots have filled in, but just enough texture is left that I have a very solid grip. Finer sand can give a smoother finish, but for pure utility the texture is hard to beat.

http://i1123.photobucket.com/albums/l545/JMadison1/Spline%20Weights/BelfastandWales069_zps99c63a34.jpg

A bit of adhesive backed felt gave a nice surface to protect the vellum and table.

http://i1123.photobucket.com/albums/l545/JMadison1/Spline%20Weights/BelfastandWales068_zpsadce25bc.jpg

There we go! Sorry for the bad photo...
http://i1123.photobucket.com/albums/l545/JMadison1/Spline%20Weights/BelfastandWales070_zps30c92f63.jpg

Next up are some custom made splines, then its time to start drawing in earnest!

BBSebens
08-06-2014, 11:47 PM
Woohoo! Nicely done.


If it were me, I'd be sorely tempted to number them, just so I can satisfy my OCD by putting them in order.

PeterSibley
08-06-2014, 11:53 PM
Very nice ! They can talk to these ones . :D

http://pic40.picturetrail.com/VOL282/9443996/24304759/408860092.jpg

Jay Greer
08-07-2014, 09:49 AM
Nicely done! Here are some of my own.http://im1.shutterfly.com/media/47a3d800b3127cca26d568b404ca00000010O00QYsmrNy5bsQ e3bjU/cC/f%3D0/ls%3D00107990352120130621212620104.JPG/ps%3D50/r%3D0/rx%3D720/ry%3D480/?tn=-34573628

Casting a set of weights is always a study in frustration for me. I never seem to cast up enough.
Jay
http://im1.shutterfly.com/media/47a3d800b3127cca26d568c7858900000010O00QYsmrNy5bsQ e3bjU/cC/f%3D0/ls%3D00107990352120130621212606601.JPG/ps%3D50/r%3D0/rx%3D720/ry%3D480/?tn=1417162293

Bill Mercer
08-07-2014, 10:15 AM
Couple of questions: Being that lead has a low melting point, could you carve out a female mold from hardwood, split it on the bandsaw for easier duck removal*, coat the inside with waterglass, then just make the ducks in that?

Also, are stick-welding gauntlets tough enough to use as foundry gloves?

* If only removal of real ducks were that easy. . . the things are pure evil and I've had them actually poop on my lunch when I didn't keep an eye on the food, rather than eating it like sensible animals.

Jay Greer
08-07-2014, 10:24 AM
My own patterns were made from wood just as J. Madison did. However, I made the molds of plaster of paris which gave a smoother finish to the weights. The lead shrinks enough to allow them to fall easily out of the molds which can be used many times. One caveat is that they should be thoroughly baked in an oven for several hours to remove any residual moisture prior to using them in order to prevent a steam explosion during the pour.
Jay
http://im1.shutterfly.com/media/47a3d800b3127cca26d56935c5e300000010O00QYsmrNy5bsQ e3bjU/cC/f%3D0/ls%3D00107990352120130621212532049.JPG/ps%3D50/r%3D0/rx%3D720/ry%3D480/?tn=581787594

ron ll
08-07-2014, 10:26 AM
Curious why the hooks could not be set into the mold and cast in rather than drilled in later.

Jay Greer
08-07-2014, 10:37 AM
I did consider that but it was less hassle to use the cup hooks afterwards. Drilling them using the drill press and a taper drill prevented jamming of the drill in the lead. Drilling afterwards allowed a bit of experimentation for the location of the hooks until the optimum position was worked out. I fussed a bit with that but, you can do wonders with modern epoxy fillers for holes put in the wrong place.
Jay

J.Madison
08-07-2014, 11:03 AM
Very nice ducks Jay!

Drilling after the fact is certainly easier than trying to cast in place. If you were doing a big production run I suppose casting in place would be best, but not for these small quantities.

The welding gloves are just a bit of a help. Don't stick your finger in the lead!

Carving a female pattern sounds very difficult. Even just visualizing what it is going to look like would be hard. I don't do much carving, and that would be beyond my abilities to get fair. Other than that it would probably work fine. I've seen people use wooden female molds for simpler shapes.

What are those ducks made of Peter? Do they have hooks or just set on/against the spline?

rbgarr
08-07-2014, 11:31 AM
Nice!

I use one as a chart paperweight and move the pointer along my course from time to time. Thus I can pretty much always go right back to the spot on the chart 'where I am'. Otherwise I lose my spot on the chart and have to search for a bit.

Hugh Conway
08-07-2014, 12:00 PM
Curious why the hooks could not be set into the mold and cast in rather than drilled in later.

I casted in place using scaffold nails in a 3 piece wood mold made to a WB article. It took much fiddling with them after the fact to account for slight differences in mold fill and mold fill angle to get all the hooks even. Next time, I'll just drill.

Thanks for the write up, I was looking to make another set :)

Jay Greer
08-07-2014, 12:44 PM
Madison, I offer my apologies. I didn't mean to hijack your post. I do agree that carving a female pattern would be a lot more work. I spent only an afternoon split into two days to allow for the drying time of the molds while doing this. I did make an acrylic casting of the pattern to make the mold casting go faster. The pink female mold was taken from the wooden pattern and was cast in silicone. The two boxes are for the pouring of the plaster of paris molds. It was a fun project that was necessitated from my being away from my office in Port Townsend. I use a variety of splines in my work. The commercial ones made up of multiple pieces of vinyl work well with the weights for tight curves and I use lucite for long easy curves. I have a lot of wooden ones I make up as well.
Jay
http://im1.shutterfly.com/media/47a3d800b3127cca26d568d1859f00000010O00QYsmrNy5bsQ e3bjU/cC/f%3D0/ls%3D00107990352120130621212021443.JPG/ps%3D50/r%3D0/rx%3D720/ry%3D480/?tn=-623405661

Arko
08-07-2014, 05:02 PM
Nicely done! Here are some of my own.http://im1.shutterfly.com/media/47a3d800b3127cca26d568b404ca00000010O00QYsmrNy5bsQ e3bjU/cC/f%3D0/ls%3D00107990352120130621212620104.JPG/ps%3D50/r%3D0/rx%3D720/ry%3D480/?tn=-34573628

Casting a set of weights is always a study in frustration for me. I never seem to cast up enough.
Jay
http://im1.shutterfly.com/media/47a3d800b3127cca26d568c7858900000010O00QYsmrNy5bsQ e3bjU/cC/f%3D0/ls%3D00107990352120130621212606601.JPG/ps%3D50/r%3D0/rx%3D720/ry%3D480/?tn=1417162293

HOLY COW MAN!!! Those are super nice!

Sea Dreams
08-07-2014, 06:13 PM
Here's a video that might help anyone thinking of casting lead or other metals in green sand.


https://www.youtube.com/watch?v=U7ut_2nqiGk

Another idea that might be of some use is to make Oogoo (http://www.instructables.com/id/How-To-Make-Your-Own-Sugru-Substitute/step3/Mixing-Oogoo/) which is a mixture of clear silicone caulk and corn starch. Maybe you could use high temp gasket maker instead of the clear silicon. The corn starch allows the silicon to set quicker from the inside instead of just skinning over and the inside remaining sticky. Might be a little cheaper than mold making silicon. I've never tried this for mold making and sure haven't tried to pour molten metal in or on it so I don't know if it would work or not. It did make a rubber like material like a rubber stopper.

Sea Dreams A.K.A. Brian

kbowen
09-12-2014, 04:29 PM
I realize and respect that there is a definite aesthetic appeal to all this which is nice if you want drafting ducks. I bought a couple very stylish ones in Maine when I started, But if you are just trying to hold a batten in place, you can get pigs of plumbers lead at the Home Depot, saw in half if you wish, screw L-hooks into them and get on with it. Scuba belt weights are also handy and are lying around in some locations. A chunk of 2x4, with an L-hook, and a paint can on top of it also works. Decide what your goal is.