Recent content by coulsea

I made a big mistake two months ago and bought a new motorbike. A Royal Enfield Continental GT 650, it has been demanding a lot of my time and I have sore cheeks from smiling so much.

I printed a top for an Upshur twin and it works well but I don't run it for very long at a time. I have also printed name plates and painted them to match the engine, putting them in the sun for the paint to dry on a hot day will deform then quite badly.

An interesting hit and miss engine that doesn't give off petrol fumes is the "Chuck Fellows" air/steam engine. Brian Rupnow built one and did up a set of plans. you can find them here...

Look up Prony brake, you might even find one on this forum.

One problem might be that the fuel tank is too high. the fuel level must be below the venturi / jet or it will flood, you should have to choke it by putting your finger over the inlet for a second to get it to start.

I have the same problem, must have got a bit of rubbish in there and it spun while drilling a 25mm hole. I have these reamers on my ebay watch list, just have not bought them yet $37 Aus they should do the job as you only have to take the bur out.

Downloads section of this forum https://www.homemodelenginemachinist.com/attachments/thread-chart-doc.109767/

there is a thread chart in the downloads section of this forum https://www.homemodelenginemachinist.com/attachments/thread-chart-doc.109767/ if you look up 10-32 it is 4.8 mm so you could use 5mm or 4mm depending on clearance around it so it does not interfere with another part. The R0.03 max is...

I don't like the carb mount. a plug in the current hole and a new hole through the side might look better. Of course the right angle path would not be good for efficiency.

Lubrication is important in these small models, they are not really designed to be used for long periods of time, 68 hours is a long time, most of my models don't get used for more than a couple of minutes at a time. I will share my plans and knowledge with anybody here because we have a common...

My Upshur twin uses one cam lobe for both intake valves and the other lobe for both exhaust. plans are dated 2001.

I had looked at a few plans before designing my own open crank hit and miss engine and the average seemed to be a stroke of 1.6 times the bore. if you go longer than that the con rod can foul on the bore at half stroke. some early long stoke engines look like adapted steam engines and have a...

A small amount of error really shows on a gear with small teeth. everything has some degree of error so it is best to eliminate any unnecessary source. your collet block has the potential for error mounting in the chuck, the collet to the holder, the collet to the arbour and the holder itself...

I have cast the cannon in aluminium bronze from the pattern that i posted earlier. Now i have to do the carriage.

I am going to cast a cannon in the next couple of days, I have drawn up a pattern and printed it on a 3d printer, given it a couple of coats of spray putty and a gloss top coat. the picture shows a gap between the two halves but it does go together properly. I will cast it in the same material...