Recent content by popnrattle

This engine resembles the Duclos engine in that it has the crank pin connecting the 2 flywheels together style(ala Harley Davidson) but that is about it. I did the overhead valve here and Philip's engine did the valve cage design. My design is a 4-cycle but wouldn't take much to make it a...

I have found it helps to place a 1/64's scale near the part I want to trace before I import into Acad to help when I scale to the size I want.😁

Those miniatures are cute when they are running at a blur's pace, but I think some folks don't understand how they run when the mechanisms are a blur. I run them slow so folks can see how the mechanics of the hit-n-miss cycle, especially the governor's role, is in their operation. Besides, they...

You can get bulk O-rings(20/pk) from E-Bay. These are the ones I use(1-1/4 OD x 1-1/16 ID). Later, Rick.

O-rings are the way to go for me cuz I like the easy way to do things, causes no wear on cyl., they last over a year and by that time it's ready to be taken apart to clean carbon and gunk from valves anyway. The hardest part for me is lapping the valves to seal well enough to run(half-hour or...

I drew a bevel ring and pinion(4.11 to 1 ratio) along with the spiders and printed them as part of an auto differential display to show students how it works. I uploaded my 2 procedures using CAD and Inventor(correct or not;)) to you tube if you care to take the time. The musical accompaniment...

I like your post and agree. The problems I have is when they replace some features that suited me at the time and have to take extra laps to use the new feature. But sometimes after a some negative responses from users they offer that old command with the word "classic". I suppose they gotta...

Brian, what was the bore ranges of the engines you have had success with the the 1/16"(.070") O-rings? Thanks. Later, rt.

you are correct in assuming they would start "rolling" as I tried a 1/16" cross-section ring with those dimensions I used with the 3/32"(.100) and the engine never seemed to run right and seemed the O-ring never seemed to "break-in"(new O-rings have a little more resistance). The 1/16" O ring...

In my engines bore is 1-3/8". My piston is .002-.004 slip. I use a Sunnen hone to get the bore straight after boring on lathe, then get a cross-hatch with the 500-grit stone(J-95). I get 1-3/8" "plumber's" O-ring with 3/32" cross-section(measures .100" at local hdwe store. Then, I make my ring...

I time my exhaust valve to seat just as the piston starts back down. Hopefully, utilizing the slight inertia of the exhaust gasses to create a possible vacuum on the intake. I put negative ramp to make valve drop to the seat. Exhaust opens around 20-30 BBDC(depends upon rocker/valve lash, of...

https://www.deboltmachine.com/

I get mine at the local hardware store for a little over a buck. Very pleased with longevity, especially with the temps involved. My engines power things with no forced cooling so, I have an excuse to tear them down clean the carbon from the valves, head and piston and replace O-ring after about...

I chamfer the hole and file a bit of a lead-in before pressing so hole won't shear OD of brg.. Sometimes need to ream to size after pressing. The sizes are from Bunting website. These are the brgs I use. Hope this helps. Later, Rick. https://www.buntingbearings.com/index.html#

I do 45 deg on the valve and leave my head seats sharp with a close fit on guides and stems. Especially on the intake stem/guide for no adverse affect of fuel mixture adjustment( like to run mine slow rpm👍😊👍). This allows the sharp seat to groove the valve head for sealing much easier/faster...