By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Allendale Jan 24th

Potty Mill engine materials list wanted

All Topics | Latest Posts

Search for:  in Thread Title in  
John Duncker 120/05/2019 22:45:16
32 forum posts

I think I will try to make a Potty Mill engine using only bar stock, I was thinking of the Stuart twin wobbler but I think it really needs a mill and I just do't have the space. Also having watched a vid of a build the bits are on the small side for my failing vision and fat fingers.

I can work my way through the Potty Mill parts list going back and forth to the dimensions on the drawings to make a materials list.

But is this just reinventing the wheel.

Has someone made such a list already and is it available online?

I would really like to get everything I need in one go as I live on a sailboat in the Caribbean and the supply chain involves multiple visits to local customs officers shipping agents and some serious bureaucracy

Thor21/05/2019 06:16:38
1236 forum posts
37 photos

Hi John,

I can't remember having seen a materials list (someone else will probably point you in the right direction), but there is a Parts List on this drawing set.


Stewart Hart21/05/2019 06:57:32
643 forum posts
354 photos

Hi John

I never compiled a material list for this engine. The material is mainly low cost aluminium and steel standard stock sizes:- though I've used metric sizes it you will be no problem using the nearest imperial size.

There have been a great number of these engines built to my plans, the drawing in Thors link were done as a drawing exercise that are over complicated, if you want a set of my drawing just send me a PM with your email address and I'll mail them you.


Hopper21/05/2019 08:54:43
4648 forum posts
101 photos
Posted by John Duncker 1 on 20/05/2019 22:45:16:..
...I live on a sailboat in the Caribbean and the supply chain involves multiple visits to local customs officers shipping agents and some serious bureaucracy

I got all the aluminium for my Potty Engine as offcuts from the local boat building yard that builds and repairs aluminium boats. If there is such a thing in your vicinity you might be in luck. Flywheel was made from an old steam valve handle that came off a ship most likely. Crankshaft webs were made from a bit of common steel flat bar cut with a hacksaw and the shafts themselves were made from computer printer guide rods. Necessity is the mother of invention when working in remote locations. Trickiest bit might be getting the very small studs, nuts and suitable taps. I bought studding and nuts off

Edited By Hopper on 21/05/2019 08:55:15

John Duncker 121/05/2019 15:21:34
32 forum posts

The plans I have were drawn by JDW of New Zealand and cover 4 A3 sheets. I downloaded it from the internet. They look OK to me and incorporate a parts list. The thread sizes are metric and I will need to decide weather to go metric or convert the sizes to the more easily obtainable US imperial sizes.

While scrounging up the bits might be possible it would be very hot and tiresome with expensive taxi rides to some locations in Grenada. In the past I spent a year trying to hunt down a piece of 1/2 inch ali bar to replace a broken hatch support without any success. Even the famous floating workshop in Carriacou did not have anything suitable. .

I would much prefer to order all the bits of bar stock from a US metal supplier like That way I know that I have what I need.

Being a US based supplier means I will find imperial sized bar stock.

I will probably use US sized nuts bolts taps and dies. If I went the BA route I would need to order from the UK.

Edited By John Duncker 1 on 21/05/2019 15:31:00

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Latest Forum Posts
Support Our Partners
Allendale Electronics
Eccentric July 5 2018
Eccentric Engineering
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest