Webster Engine Question

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bmac2

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I’ve been thinking about taking the plunge for my next build and doing an IC engine.
Now what I want to do is something like this.

IHC-Model-M-Green-Left-950.jpg
 
So I have a couple of questions:
I can’t source Dura-Bar or Cast in my area and I have some 1018. Is the 1018 suitable for the cylinder.?
If using a fuel (Naphtha)/oil mix, is the cylinder oiler necessary?
Which runs cleaner, the cylinder oiler, or premix fuel?
 
Hi Bob,
Cast iron is the best material for IC engine cylinders as wel as pistons because of its carbon content. For such a small engine a should go for a cast iron piston because the thermal expansion is the same as the cylinder. This gives a good compression when the engine is cold.
The oil flow of a small cylinder oiler is difficult to control because the oil gets thinner when the engine warms up.
I should go for a gasoline-oil mixture fo say 30:1.
Success with your engine.
Kind regards,

Johan,
The Netherlands.
 
Hi Bob,
I'm one of the dozens (hundreds?) that have built a Webster. It was a fun project that goes together well and allows one to do pretty much anything (in reason) for materials.
My drawings shown 12L14 as one material suggestion for the cylinder. That's what I used. It's readily available and machines nicely. Besides, if you're sticking with a ringed aluminium piston you've no worries about running similar materials "on top of" each other.
That leaves you with only needing cast iron for the rings. There's always mail order (what I did; living in Vernon BC). Another option would be to check with the oldest hobby shop in your area ... they may still have a piston ring or two in a close-enough size for repairing model engines hanging around from when people used to fix stuff. You could resize the piston/cylinder accordingly.
As far as the oiler goes - I reckon you could go either way (pre-mix or oiler). The oilers are somehow appropriate to the character of the engine though. It's going to get "dirty" anyway you lube it ...
In the end - have fun with it; it's your engine and anyway, I don't think there two the same out there.
Cheers
Charlie
 
I'm in the planning/researching stage of building a Webster; some of the information I have found may be of interest to you.

Here are a bunch of links on making piston rings (scroll down to "Piston Rings"):

https://sites.google.com/site/lagadoacademy/useful-links#misctools

Also, Enco sells "gray iron" (which I'm pretty sure is Durabar) in 12" lengths - buy it with one of their free shipping offers and it's a good deal.
 
Thanks guys for the info.
Johan: The more I think about it the pre-mix has to be the more reliable and consistent way to lubricate the engine. I notice that in the plans I have it mentions that the unburnt oil in the exhaust lubricates the timing gears.
Charlie: How’s my favorite province fairing with this crazy winter, haven’t heard much over all the crying coming out of stickpokeOntario. GREAT tip about the hobby shops. Snooped around a couple in the area and saw some SUPER TIGER 40? or 45? rings that look close (close being ambiguous when I haven’t bored the hole) for around $9.00. Quick Google search says .860” as opposed to the .875” called for in the plans. Found out some hydraulic cylinders use cast iron piston rings from 1/2" to 3". Haven’t managed to dig up any specs or prices but this is “oil country” someone has to have them.
“When people used to fix stuff”
Blasphemy! If people start fixing stuff when it brakes we’d kill the global economy. Next we’d start demanding a reasonable degree of quality in consumer products.
Kquiggle: Link bookmarked and e-mailed to work (breaks onlyRof}) I found out Metals Supermarket doesn’t carry Dura bar but can order it for me. For this one I think I’ll go with the 12L14. I think one of the best things about the Webster for a first IC is the mountain of information out there on it.
 
Hey Bob - glad you're getting a plan together, that's usually half the battle! If you do decide to mail order some cast iron you might want to check with College Engineering. Send them an email to check on shipping but you might be surprised ... probably less expensive than from the States and certainly faster.

http://www.collegeengineering.co.uk/CastBar.htm

I have used them for cast iron bar and a couple of their casting sets (adjustable angle plate and Keats angle plate).

Winter? - hardly had one. I think it hit -20c for maybe 4 days all season. Still a skiff of snow on the ground but it's the end of February - how long can it last. Expect to have the Ducati out in a couple/three weeks!

Cheers
cw
 
Bob;
Howdy from the sunny Okanagan! I went thru this cast iron exercise recently and had no luck finding material this side of the border - Edmonton had it but it was special order and you had to order at least 12 feet of it :eek:.

Like you I found metals Supermarket didn't stock it - I've ordered from then several times and found then frustrating. They have several stores in Vancouver metro and each has different stock. Worst was the way they packaged the materials and shipped. I stopped using them once I cottoned on to Online Metals in Seattle - great service. They don't list cast iron unfortunately. Haven't tried Enco or Speedy Metals (yet) for cast iron.

I'm going to try cast iron hand weights from Walmart's sporting department :eek: and see if that works. Didn't encounter any voids or hard spots when I was slicing it up. Haven't tried it in the lathe.

I'd be inclined to follow Charlie's recommendation of 12L14 for the cylinder liner and buying the Super Tiger rings - can't see a slightly smaller bore causing an issue other than a quick check of rod to liner clearance.

Charlie - hello to another Ducati lover - ex Ducati 250's and 350's. I want them back!!!

Cheers Garry
 
Garry – You tempted me.
Was driving past Walley-World the other day and remembered you mentioned cast iron hand weights. They didn’t have any 3lb on the shelf so I had to drop a whole $5.00 on the 5lb weight. I’ve never worked with cast-iron but after about 45 minutes in the 4x6 (I have got to get a new blade) this stuff doesn’t look bad.

100_1910 (Medium).jpg


100_1902 (Medium).jpg


100_1903 (Medium).jpg


100_1904 (Medium).jpg


100_1905 (Medium).jpg
 
Luxury, bloody luxury.....a 4x6..... I had to use a hacksaw :p

I'm looking forward to seeing the results, I've been reluctant to make a mess of my freshly cleaned lathe!

Cheers Garry
 
Hi Bob
Here's a little tip for your band saw. I bolted a couple of pieces of 20x20x1.6 angle onto the legs across ways using the top elongated holes provided and an old roasting dish to make a slide in slide out chip tray.

Good luck with your projects
 
Hi Hat – Or should that be g'day mate. That sounds like good oil. My 4x6 lives in the (unheated) garage and most times in the winter it’s run out – cut - and get back into the house so it can get pretty rough under it by the time I give it a good cleanup in spring.

GMAC – Man, a hacksaw:eek:? My little 4x6 was a dumpster-dive with no motor, a broken pivot casting, no damper, and a bent base, but I’ve said before and I’ll say it again. "If it wasn’t for that thing I’d be collecting stamps". Those iron weights with a hacksaw? Please tell me it wasn’t across the big end.:bow:
 
Ok. Well the lathe was overdue for a good cleanup anyway so I thought I’d “take one for the team” and see how this stuff cleaned up. Like I said before I don’t have much experience with cast iron but this stuff does seem hard. It cleans up ok, but tough to get a nice finish.

180 Feels Hard.jpg
 
Is all Cast Iron the same? Or are cast Iron pipes different because they are extruded?
 
Bob, you will find that it will always be hard to get a good finish on cast iron due to its grain structure. Even if you polish it, the surface will always have pits in it. Of course, the better the quality the smaller the pits are.

Paul.
 
Hi Robcas - Looks like some of it will machine real nice and some is full on mystery metal. Pipe sounds interesting. Not all iron pipe would be old water pipe. Depending on its intended use it could be some nice stuff.
Thanks for the input Paul - I guess that’s why it’s so good for cylinders, all those little pits holding oil.
Hat56 – Took a measuring tape to a couple of old cookie sheets my wife was going to trash. There about 16 x 12 and just over an inch deep. Just might fit the bill.
 
I've never heard of extruded cast iron. I think a lot of the pipe from places like Home Depot and Hardware stores is actually steel, and a pretty poor grade at that. I tried making a cylinder out of a 3/4" pipe nipple I got from Home Depot and it was miserable. It was gummy and I couldn't get a good finish on the bore. I finally tossed it out and used cast iron rod, boring it out to the desired diameter.

Chuck
 
Steel pipe is seam welded, it is garbage, there is a good chance that a lot of it is China made too.
If Moly, or DOM (drawn over mandrel) tubing is available , from a tool shop or supplier, it is excellent material for making little components.
 
Hi Robcas - Looks like some of it will machine real nice and some is full on mystery metal. Pipe sounds interesting. Not all iron pipe would be old water pipe. Depending on its intended use it could be some nice stuff.
Thanks for the input Paul - I guess that’s why it’s so good for cylinders, all those little pits holding oil.
Hat56 – Took a measuring tape to a couple of old cookie sheets my wife was going to trash. There about 16 x 12 and just over an inch deep. Just might fit the bill.



I was just asking a question and meant no harm. The more I learn, the more I realize how much is involved in the machining process. Physics, Chemistry, Metallurgy, Math and a lot more. I read about the different cast irons that exist, their properties and chemical structure. It's complex! I suppose that is why I find machinating interesting.
 
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