Hi, also know as Woods metal, its a very low melting point metal that can be poured into a tube at about 180f, it then solidifies so you can bend the tube then heat it up and pour it out
A 15cc sidevalve opposed twin
- Thread starter Peter Twissell
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Regarding a fill material for the tubes before bending - I followed a tip I read elsewhere and got a 1l tub full of the waste grit after shotblasting. This is the fine stuff filtered out of the blasting circuit. I sieved this through a teastrainer, which gave me very fine material. After pouring into my tubing and sealing both ends, there was no collapsing of the tubing when bent.
Hi. I have never had success with sand. I have also tried ground glass which I use in my "sand blaster". This is 1 micron gauge but it still moves in the tube. When I have tried to use it I have capped the tube ends to keep the sand/glass locked in place. I have also used screws in the cap to add compression. My greatest success has been using lead as a filler. I think there is a low melting point metal alloy which would be better but I don't have any. The lead can be reheated and either blown out of the tube or allowed to run out (safety issues etc). Hope that helps
Mike
Mike
Hi, Mike, any input helps, thanks. The low melting point metal you refer to is known as cerrobend to the trade and generically called Woods metal. I have manage to aquire a small amount, but also have access to a sand blaster with fine grit. I will try both methods till it works
Harglo
Well-Known Member
I have been successful with filling the tube/s with solder. Doesn't take too much heat to re melt out.
Harvey
You could try the outer sheath of an old electric immersion heater, it's normally stainless steel - and pre bent to quite a tight radius at the ends and straight lengths as required for further small bends as needed. The double loop type are better and you can get 4 or 5 pipes made up.
Hi Majormallock. Woods metal was the material I couldn't remember. Probably better than lead since I understand it doesn't stick to the sides of the tube. Lead or solder (without flux) does tend to leave deposits. When I wanted to tightly bend copper tube (10mm dia) I made 2 silver soldered end caps with a M6 thread. I then filled the tube and tightened up the M6 cap head screws to ensure compression. It worked but I can't remember the rad I achieved. I did however get better results with lead and it was easier. Best of luck and I will be interested in the result. Good project for Christmas!
Mike
Mike
I have had success with both lead solder and candle wax for filling copper and brass tubes for bending. I have some simple hand benders, but they do the job well.
I did read of someone who crimped one end of a tube in the vice, filled the tube with water, then crimped the other end, and had successfull bending. But there must be no air inside the tube, and hydraulic sealing at the crimp.
K2
I did read of someone who crimped one end of a tube in the vice, filled the tube with water, then crimped the other end, and had successfull bending. But there must be no air inside the tube, and hydraulic sealing at the crimp.
K2
methuselah1
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I have a "brick" of low melting point alloy, which I have used on occasion. When I say "low" m.p. I mean you can melt it back out with boiling water in an old saucepan. However, my stuff contains bismuth, and EXPANDS (a lot) on cooling- its use is carefully considered before each job.
Has anyone mentioned paraffin wax yet?
Has anyone mentioned paraffin wax yet?
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According to a "How Its Made" video they make trombone brass tubing bends by annealing the tube, filling it with water, freezing it, and bending in a standard looking tubing bender. If needed, the inside diameter of the bend can be maintained by ball sizing which would require a die to hold the bend. I have never tried this method but they make it look easy. Go to 2:45 of the video.
Jeff
Jeff
Loved the video, ball bearing method very clever. Frozen water worth a try! Not heard of paraffin wax, I'll put it on the list if all else fails
Aluminium spring caps are counterbored to lock E clips to the valve stems.
Assembling the valve springs, caps and clips is fiddly, the only access being the 9mm bore in which the tappet will run.
I could have provided access through the underside of the block, but that would require a cover and fasteners - more weight.
Assembling the valve springs, caps and clips is fiddly, the only access being the 9mm bore in which the tappet will run.
I could have provided access through the underside of the block, but that would require a cover and fasteners - more weight.
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Electroforming:
A few members have expressed an interest in this process, so I shall endeavour to describe my efforts in as much detail as possible.
There are numerous websites which detail the process. I have been using this one: Electroforming Resources for Aspiring Artists
My patterns for the first couple of test pieces are 3D printed in PVA resin, which is soluble in water, making for (hopefully) easy removal when the plating is complete. The parts are built with the minimum of material, i.e. single layer wall thickness and just enough internal support structure to enable a successful print.
One end of each part is pierced and a copper wire (recovered from old domestic wiring) is pushed in. This will form the electrical conductor for plating, and will also support the part in the tank.
A few members have expressed an interest in this process, so I shall endeavour to describe my efforts in as much detail as possible.
There are numerous websites which detail the process. I have been using this one: Electroforming Resources for Aspiring Artists
My patterns for the first couple of test pieces are 3D printed in PVA resin, which is soluble in water, making for (hopefully) easy removal when the plating is complete. The parts are built with the minimum of material, i.e. single layer wall thickness and just enough internal support structure to enable a successful print.
One end of each part is pierced and a copper wire (recovered from old domestic wiring) is pushed in. This will form the electrical conductor for plating, and will also support the part in the tank.
Attachments
The patterns are painted with conductive paint, covering only the surface to be plated, with the addition of a generous 'stripe' connecting the area to be plated to the copper wire.
The end faces do not require plating, but the PVA material will begin to dissolve when it is immersed in water, so it is necessary to cover the ends. For this purpose, I used matt black enamel paint, just because it was to hand and is fairly quick drying.
The conductive paint dries very quickly.
Shown here are the painted patterns, supported in the tank (HDPE ice cream tub) along with the anode, which is a length of 15mm copper domestic plumbing pipe.
The surface area of the anode needs to be approximately twice that of the cathode. The cathode surface area is the total of the parts to be plated.
The cathode surface area also needs to be known in order to calculate the plating current. This pair of parts will require 0.8 Amperes.
The end faces do not require plating, but the PVA material will begin to dissolve when it is immersed in water, so it is necessary to cover the ends. For this purpose, I used matt black enamel paint, just because it was to hand and is fairly quick drying.
The conductive paint dries very quickly.
Shown here are the painted patterns, supported in the tank (HDPE ice cream tub) along with the anode, which is a length of 15mm copper domestic plumbing pipe.
The surface area of the anode needs to be approximately twice that of the cathode. The cathode surface area is the total of the parts to be plated.
The cathode surface area also needs to be known in order to calculate the plating current. This pair of parts will require 0.8 Amperes.
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First mistake / discovery:
In order to dissolve the copper sulphate into the water, the water must be warm. It's about 18 C in my house - not warm enough for the solution and most of the copper sulphate just sits in the bottom, refusing to dissolve despite much agitation.
I had mixed the solution in a plastic milk container, so I was able to simply stand it in a bucket of hot water and within a few minutes the solution was complete.
In order to dissolve the copper sulphate into the water, the water must be warm. It's about 18 C in my house - not warm enough for the solution and most of the copper sulphate just sits in the bottom, refusing to dissolve despite much agitation.
I had mixed the solution in a plastic milk container, so I was able to simply stand it in a bucket of hot water and within a few minutes the solution was complete.
I have only done hobby nickel plating and that was a few years ago. Fish tank accessories are good and cheap, a heater to keep the solution at the correct temperature and a small submersible circulating pump to keep the solution moving. Current settings made a big difference in finish quality, Smoothness etc. Good luck! Very interested in the outcome. 
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Thanks Basil.
I have done some electroplating in the past. I have managed without heaters or circulators, simply occasionally stirring the solution manually and setting the plating tank in a dish of warm water.
This process only needs to be kept slightly above room temperature and I suspect the plating current itself may be sufficient to make up for the slight heat loss once it gets going. If not, I will top up the heat with more hot water in the dish.
I would be concerned that fish tank equipment might suffer corrosion from the acidic solution.
I have done some electroplating in the past. I have managed without heaters or circulators, simply occasionally stirring the solution manually and setting the plating tank in a dish of warm water.
This process only needs to be kept slightly above room temperature and I suspect the plating current itself may be sufficient to make up for the slight heat loss once it gets going. If not, I will top up the heat with more hot water in the dish.
I would be concerned that fish tank equipment might suffer corrosion from the acidic solution.
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