Making a maul - question?

[dikman]

That was cast from scrap brass that I've collected, although I have a fair amount of used brass cartridges that I'm thinking about melting down. The first one is steel, and although I can forge the stuff I can't melt and cast it.

[JazzBass]

Excellent!

You sure COULD go into business with these, if your were so inclined - but I respect your decision to only make your own.

Beautiful work!

[OwenSweenie]

Indeed, it looks fantastic! Great job!

[dikman]

For anyone else wanting to try melting plastic to make anything, my latest "test" results. I tried making another maul head and used the fine turnings from my previous one. Now, this "should" have melted easier and fused better according to my reasoning. Unfortunately it tended to be somewhat spongy and took a lot of pressure to squeeze it together, so while it worked I'm not overly happy with the result (plus the plastic appeared to scorch so looks brown). The best results came from using the milk bottles cut up into approx. 3/4" squares.

I tried another smaller one, in half a tin, but rather than use the oven I placed a few pieces in the bottom of the tin and used an electric heat gun to heat the plastic until it was transparent, then added more pieces, heated again and so on until the tin was full. Every few layers I used a piece of wood to ram the molten mass down. I then clamped the resultant mass to squeeze it together and left to cool. This was quicker than using the oven and the lump at the end looked pretty good with a fairly uniform white colour and minimal flaws.

Like many things, the process looks easy.........until you try it!

[GRod]

9 hours ago, dikman said:

I tried making another maul head and used the fine turnings from my previous one. Now, this "should" have melted easier and fused better according to my reasoning.

I would have assumed exactly the same thing.  I'm surprised it didn't work out that way.

 

9 hours ago, dikman said:

This was quicker than using the oven and the lump at the end looked pretty good with a fairly uniform white colour and minimal flaws.

This also surprises me.

Thanks for sharing these notes.  I am fascinated by the idea of melting and molding (moulding? ) waste plastic into useful stuff.  Since I don't have ready access to a lathe I am looking out for a suitable drinking vessel or tumbler like @heydox used for his mold.  I figure if I can get close I can fine-tune it on my drill press.

I also found a US plastics dealer, a small shop by the looks of things, who deals in all kinds of shapes & sizes of all kinds plastics.  He offers 'rods' made of Delrin (acetal?) and HDPE particularly, which are 12" (30ish cm?) by 2.5" - 3" (6 - 8 cm).  I'm guessing that Delrin is a name-brand formulation of something more generically known as acetal.  Something like that would be a nice jump start to a maul, but it does reduce the cost-effectiveness of a DIY solution.  Besides, a 3" diameter piece of Delrin is really expensive... at least in this format.  Regular old acetal and HDPE are pretty affordable, and I would bet one could create three or four mauls from a single 12" stick of the stuff.

But I really want to melt down my own scrap.  Because... well...  fire & metal and all that. 

[dikman]

GRod, sometimes you can find old pewter drinking vessels at thrift shops which might be suitable (not too big and often have a conical-type shape). We once had a set of aluminium drinking cups that were a similar shape. You can use a gas torch to melt the HDPE but you have to be careful as it can scorch the stuff, and while it will still work it looks a bit unsightly. The trick with molding this is to keep pressing it down to force it together and work out any air bubbles.

Another chap on youtube uses a sandwich toaster thingy, one that is flat inside, and uses non-stick cooking sheets to stop it sticking. Great for flat sheets, but I guess you could roll the sheet into a cylinder and then force it into a mold?

I've started looking at he bottom of plastic containers now, checking for the #2 (or 4) code! Bit of a worry.......

[dikman]

GRod, I turned this piece on the lathe to see what it was like, it's ok but could be better. There are obvious small areas, mostly on the bottom, where the mass hasn't fused properly. I think what probably happened is that because I was slowly building up the "layers" in the tin the bottom area was slowly losing heat as I got closer to the top. By using an oven the tin is constantly returned to the heat source so the mass retains the heat better.

My method using the oven was to place an enamelled tray in with the tin on it, put some pieces of plastic in the tin and also put some on the tray to melt, when I removed the tray I squashed down the plastic in the tin and used a paint scraper to lift the stuff off the tray and put it in the tin then squashed that down. Then repeat the process, and repeat and repeat......Don't put too much in at a time or it can take a while to melt.