Recent content by coulsea

A very enjoyable thread. I recently had a comment to one of my posts about my way being unnecessary ( no i am not offended) and it made me think about the right and wrong ways of doing things. model building is generally just a way for people to enjoy themselves so if you are having fun you are...

This is what I use. to get the curved holes I drill the main hole (6mm) 6mm in from the end which will leave 3mm of metal between it and the end, then with a 6mm round file, file down from half a hole to the side of the first one and when it breaks in to the first one it will naturally take the...

The first time I used O rings I thought that two must be better than 1, it would lock solid after a few turns.

Jasonb. I have changed my spreadsheet to use your 1.4 for module 1 or less and it will change to 1.25 above module 1. It is a small change but I think that it will be good for my 0.5 module gears. I made this spread sheet because it is simple and doesn't give a heap of values for things that you...

I get 2.25mm depth of cut using my spreadsheet.

good work. Be patient it will improve as it runs in, particularly the valves. It will start and run at lower speed once it is run in and when it will start reliably you can adjust the intake valve spring so that it closes the valve with very little tension when closed, this improves the...

I Agree the best way to seat valves and get rid of tight spots is under fire. it sounds like you were nearly there, put the throttle in the middle of the range that works and adjust the mixture while it is banging away. 10 to 15 second burst on the drill and you will get there. the mixture will...

A bit more clearance in the intake rocker will make the intake valve open a bit later to avoid overlap or move the cam one tooth so that exhaust closes and intake opens just after TDC.

These engines are meant to run, not set the standard for horsepower or fuel efficiency. you have quite a bit of leeway when it comes to valve timing. valve clearance will affect the timing and can be used for a bit of fine tuning once you get it running. I am starting to make one but have only...

Model IC Engines (john-tom.com) 3rd one on this page is the webster, lots of builds on this forum. not free but not expensive, the red farm engine gives lots of options UpshurEngineWorks - rocketr.net

The carb should suck not blow. valve timing being out by 1 degree is insignificant. as long as the exhaust valve closes at or just before TDC in order to get the full intake stroke.

Looking back at your video I notice that you don't touch the carby. I have tried those carbs and found that they don't function like they should because they are designed for a different fuel and a different rev range. Not saying it's no good but it may only work through part of the throttle...

My battery drill will not start a new engine, just not fast enough (1200 rpm should work), if you have leaks in the valve block, valves, rings and head it all adds up to not enough compression to fire. intake valves don't move much, a finger over the intake will tell you if it is sucking at all...

The upshur plans for the red farm engine include plans for horizontal air and hopper cooled engines with a choice of two different head designs and the open crank vertical with the two head designs. The enclosed crank vertical with the two pushrods is another set of plans, purchased separately...