Member postings for Tim Rowe 1

+ 3 for Captain Tolley's Creeping Crack Cure to give it its full name.

It is a low viscosity acrylic compound that cures in the presence of moisture. It will tolerate some moisture in the crack it is sealing. If there is a crack it will "wick" in instantly. When it won't wick anymore the joint / crack is full. Sometimes it needs 2 or 3 goes and works better for that rather than trying to do in in one hit.

When cured it remains flexible so is idea when sealing different material and where expansion and contraction are involved.

I would be lost without always having a bottle in the cupboard.

Tim R

Hello Stuart

I build RC yachts and race IOM yachts. Mine tend to be built for performance rather than scale so are likely to be more stressed than yours. I frequently glue aluminium bits together and only ever use the slow cure Spanish version of Araldite which is always to hand. I have never found it necessary to buy special products or use special processes for the very small usage. I have two types of Loctite that get quite a lot of use on assemblies and fastenings. The important things to do are:

Consider the gluing area. Aim to make it as large as possible within the design constraints.

Try to design the fitting to avoid peel forces.

Clean and lightly abrade: Here I do a first clean with acetone turning the cloth at each pass to avoid re-depositing grease or dirt. Acetone is a fast solvent so it is quite easy to just move contaminates around if you are not careful. Then I rough the surface by pulling across a Permagrit block and then a final single, one direction wipe with a clean cloth and acetone. I have already mixed the glue and as soon as the acetone has evaporated which is seconds only, on goes the glue. This seals the surfaces and reduces the time available for the aluminium to oxidise. I use plain and pre-anodised sections with equal good effect.

Very occasionally I may pin or rivet a joint as belt and braces using thin brass rod and peening over the ends.

I too sail on the sea but don't worry too much about corrosion even with dissimilar metals. The boats are only out for a few hours at a time and in-between get a good rinse with fresh water. The rest of the time they are in the house.

I also use brass mainly for decorative reasons and of course that can be soldered. Would that be an option for you particularly if you are not too bothered about weight.

One day I am going to try the techniques for soldering aluminium hoping that will enable me to refine my designs. My obsession is keeping the weight out of the hull and rig so I can put it in the keel.

Tim R

You can also pressure die-cat brass casting a number on the same runner or sprue. It is quite possible that the texture is some kind of post finishing like rumbling before machining.

Tim

Buffer has it correct. A vessel has to have a positive Metacentric Height to be stable. The cg can be above the cb.
His diagram shows that the cg stays fixed but the centre of buoyancy moves outwards creating a righting lever. All the time you have a righting lever the vessel will return to upright (wave motion excepted) but once a certain angle of heel reached, you are going to get wet.

If a ship is carrying a very dense cargo such as iron ore, the cargo is built up into a pyramid to raise the cg. Otherwise the ship could be too stable and be over-stressed by the more violent motion this would produce.

The is a high speed superyacht that was built with an alloy hull to save overall weight and a steel superstructure to make it less twitchy and more comfortable. It is true however that the other way around is the norm.

Tim

Looks to me like an exothermic reaction has started. There is a lot of oxygen tied up in rusty iron or steel. Introduce a reactive metal such as aluminium which could still be stuck to ferrous material even after magnetic separation and you have a process akin to Thermite.
Get the steel hot enough and even that will "burn" as can easily be seen in oxy-gas cutting processes.

Tim R

+1 for Tufnol

A delight to machine and the smell - aah! memories of my granddad's workshop.

Tim

Keith

I am sure someone on a sister forum modelflying will know. You can find them here
Looks a nice engine.
I have some engines where the prop driver has been drilled but only a few holes and probably for balancing. Lightening would seem a bit of s waste of time but most prop drivers have knurled contact faces arranged radially to grip the prop. The holes would do the same I think but a bit OTT.

Tim

For me the most likely explanation is linked to the longstanding and current description for the length of a boat / ship / vessel etc

LOA Length Over All

Another term is LBP Length Between Perpendiculars which is more used in Naval Architecture as in basic terms it ignores length that is not in the water.

No Way
They would be much more likely to find a way to put a tax on Muddle Engineers.
Tim

I am going to have a wild guess.

Something for measuring cams.

It'll never run. He did not line up the timing marks!

Go to the sister forum modelflying.co.uk and find out about control line wire. It would seem to have the properties you are looking for. Stainless steel braid. 100% UV proof, flexible and strong for obvious safety reasons.

Copper and stainless steel are widely used together in the marine industry both above and below the waterline. Many rudder fittings are riveted with copper rods belled over. Above the waterline it is common practice to put an eye in a stainless steel wire or wire rope up to around 6mm diameter. The eye is made around a stainless steel thimble and the tails are crimped together using a talurit which is basically a thick walled copper tube swaged onto the wire with a special tool. Provided the copper is well annealed to start with, you can get a considerable upset. Best to use a fewer number of heavy strokes rather than lots of soft ones as copper work hardens rapidly.

On a 6" chimney I would have though 1/4" is as large as you want to keep nice proportions. Go for it!

SteveItee's mate is correct and the old adage that a good paint finish is at least 95% in the preparation. Red Oxide - "Off with its head"!