Search found 1901 matches

by Lopez Mike
Thu Mar 17, 2022 4:43 am
Forum: Technical - Engines and Boilers
Topic: Better Piston Rings
Replies: 14
Views: 6308

Re: Better Piston Rings

About a zillion small gas engines have a 2.25" bore. They've been working well for me.

Like these: https://www.ebay.com/itm/380211780861

Mike
by Lopez Mike
Tue Jan 18, 2022 3:46 am
Forum: Members' Websites and Boats
Topic: boat plans
Replies: 14
Views: 9718

Re: boat plans

I love the lines of Panatella but I have talked to people who steamed her and they said that the boat was amazingly unstable in roll and sensitive to crew placement. Needed more beam. I have no idea about your power plant. Size? Power? Weight? I am very happy with the hull I have built. Same lines a...
by Lopez Mike
Sun Jan 16, 2022 3:34 pm
Forum: Members' Websites and Boats
Topic: boat plans
Replies: 14
Views: 9718

Re: boat plans

I agree with what Bart has said. I went the Stitch and Glue route and have no complaints except that it's a moderate pain to achieve the small area of compound curvature near the bow at the chine. Nothing is cheap these days. My materials bill for a 25' hull, plywood, glass cloth and resin, ran $5K ...
by Lopez Mike
Tue Dec 21, 2021 6:47 am
Forum: Anoraks Corner
Topic: Christmas Puzzle?
Replies: 4
Views: 20157

Re: Christmas Puzzle?

I vote for the hydraulic bike brakes on the large wheels. Two master cylinders as per Ron's suggestion. I've used this on ultralight aircraft which are about the same weight as his setup. Maybe more. It's very mature technology. Works fine when wet as well. And amazingly light! The Sturmey Archer un...
by Lopez Mike
Sun Oct 31, 2021 9:53 pm
Forum: Sales and Trade
Topic: Dynamo/Gen Set
Replies: 15
Views: 17452

Re: Dynamo/Gen Set

I have the drawings for the Firefly gen set and it is the Sirius. No differences that I can see. It supplied 6V at around 4A to charge a small lead acid battery that powered a small morse code radio set for clandestine service. The boiler was an ordinary pressure cooker doubled in height. No condens...
by Lopez Mike
Mon Oct 25, 2021 2:42 pm
Forum: Technical - non Engines and Boilers
Topic: Wooden bearings
Replies: 28
Views: 19679

Re: Wooden bearings

Thanks Ken, As to things like acetal resins getting hot, heat is caused by friction. The coeffient of friction with materials like Delrin and Teflon is so startlingly low that hardly any heat is generated. A pumped oil bearing is the gold standard of low friction and zero starting force. The extreme...
by Lopez Mike
Sat Oct 23, 2021 2:38 am
Forum: Technical - non Engines and Boilers
Topic: Wooden bearings
Replies: 28
Views: 19679

Re: Wooden bearings

I've seen them in a number of applications. There is one thing in common with all of these successful uses. Low speeds and little resulting heat. All of the various wood treatments don't do much for thermal conductivity. As soon as there is much heat generated, things go downhill. The smoke gets out...
by Lopez Mike
Wed Oct 20, 2021 1:07 am
Forum: Technical - Engines and Boilers
Topic: bearing tolerances
Replies: 12
Views: 6452

Re: bearing tolerances

Don't tell anyone but I've been 'experimenting' for forty years with plastic wrist pin bearings on small Stuart engines up to and including the well known #5. I use Delrin (acetal resin) on a tool steel or S.S. pin (polished surface) with zero to less than zero clearances. It takes sharp cutters and...
by Lopez Mike
Mon Oct 18, 2021 7:45 am
Forum: Technical - Engines and Boilers
Topic: bearing tolerances
Replies: 12
Views: 6452

Re: bearing tolerances

A small knock? Only a small knock? What a lucky dog you are! Laughing aside, most of the knocks I've chased in small engines haven't been the big end. They've been reversing loads that don't include much rotation. A rotating journal spreads the lubricant around and at a surprisingly low r.p.m. devel...
by Lopez Mike
Tue Oct 12, 2021 11:54 pm
Forum: Technical - Engines and Boilers
Topic: Stainless steel tubes
Replies: 30
Views: 13014

Re: Stainless steel tubes

Hmm. They certainly would have the wall thickness to last forever! And strong enough. You might have to clean off any paint or such. Whether the extra wall thickness would be a thermal issue don't know. Fred and others with more technical experience and regulatory knowledge will chime in here for su...