Member postings for Old School

You have an ER32 set up for your mill have you done the same check on that set up it would help identify if it was the collets or the chuck.

Always have three or four projects on the go, variety is the spice of life.

Dean a very impressive engine and sound awesome followed the whole thread very interesting. I did my apprenticeship in the merchant navy the ship were powered by straight 4 or 6 cylinder 2 stroke diesels turbo charged so I new it work. Looking forward to your next project.

Hope to be in NZ on holiday next year would love to see it.

KWIL thanks one on its way a useful supplier will be using them again

Jason I have read about his engine I will contact him to see what he uses, I don't really understand inserts and was given the part number of the one he uses, they are not cheap around £100 each. I don't have an engineering background my father was a clockmaker and always had access to machinery my passion is fast models currently tether cars I hold the British records for the 3.5cc class and the 10cc class this car has done just over 200mph actual speed. Working on the 2.5cc record now got within 1 mph building a new car for this season three engines to rebuild hence the piston project.

It is a PCD insert these have a diamond coating on them that allows you to take very small cuts less than a thou, standard inserts for cutting aluminium won't take the small cuts you end up putting on two or three cuts and it finally cuts and the piston is undersize and scrap. If I cannot find an insert I will end up lapping them which will do the job but you loose some performance. Just a bit of background the engines are 2.5cc and typically run around 40,000rpm the Pistons don't last long before they loose the nip. The liners are brass hard chrome plated and tapered so at the top of the stroke the piston is an interference fit the nip.

I am looking for one Mitsubishi CCMH060204MD220 insert I have searched the internet and not found one. It is for machining high silicon content aluminium Pistons for my 2.5cc tether car engines. I have machined up 8 blanks ready for final machining to size to fit the liners.

Thanks Michael which ones do you use bi metal or all hss?

Can anyone recommend a source of good quality hacksaw blades for general use in my workshop. Most of my recent purchases have been very poor.

Neil

i am using these inserts Sumitomo CCGT 09T304 NAG-H1 Carbide Insert (Non-Ferrous) but am not able to get the very small cuts that you manage to achieve. For the next pistons I am going to lap them to final size. I know I will loose some rpm but I won't scrap so many Pistons during machining.

See this https://katalog.mav.cz/detail.php?id=14128 the exact tool

All our calibrators were made of brass either the plate type or tubular, the extruder output controlled the speed but you needed to cool the product as its produced on our faster lines we had a series of cooling tanks the first one under vacuum when producing pipe the rest just water sprays.

I have done over 20 rears in the plastics product manufacturing including extrusion don't know what you mean by a jig for extrusion are you talking about the die head or the down stream equipment.

I have used Steve's spreadsheet and have cut two sets of unequal bevel gears works a treat. The actual cutting is a bit long winded but it works.

They make good stands for Christmas trees

GWR fasteners do color fast stainless washers

Reeves do a V twin double acting engine, unfortunately it does not always self start in forward and reverse the V is not wide enough. Mine powers a small radio controlled Victorian steam launch.

You really need to use 316 stainless steel seamless tube, mild steel can be used but you can get scaling in the boiler with potential to damage the engine. What engine are you going to use the boiler on.

I am a bit out of touch with suppliers now days but M Machine are very helpful.

Don't use silicone rubber for the seal

Paul it was a spectacular run, the revs the engine did went it was airborne I thought it would have flown. A credit to your hull construction that it was in one piece when you got from the bottom of the lake.

Olly