2010 Week 24 in Review

This week, OTM Inc got back aboard the Maris Pearl to get ready for some serious engine work. We organized the tools on board and cleared out a space in the shop, then we worked late one night to move the two spare cylinder heads into the shop and pull them out of the crates.

We also brought all the spare valves and jewelry from storage to assemble the heads. The new valves and new seats looked great! We did do a bit of lapping so we could easily see where they meet.

Thanks to Ed Ehler at EMS Marine for use of the forklift – we would have had a terrible time loading the heads with out it.

Then, we bought three head gasket kits from Brunner enterprises. They have a lot of Enterprise parts on the shelf, but be sure to look up the part numbers before you call. At the end of the week, we moved the boat to Ballard Oil, took on fuel, stripped down the number one head, and pulled apart the oil filter

Lightship Request for Proposals

This week we also finished up some details on the draft Lightship No. 83 Request for Proposals for Phase One Construction Activities, and sent it off to the state DOT for a final look-over before we go to press.

2010 Week 4 in Review

Valve-grinding: a team effort

This week, I finished cleaning all the valves for the Thea Foss. Engineer Ron ground the valves and observed that “the first one is fun and the rest of the 24 are boring,” which I definitely agree with. Then Vince came out of retirement and over the mountains to grind the seats, and we had a nice team to get the job done efficiently.

A visit to the Cape Cross

Later this week, I visited the crew of the Enterprise-powered fish tender Cape Cross. The engine’s running well and best of all, the boat is gainfully employed.

Dry-suit repairs

After last week‘s brush with carotid sinus reflux, diver Duane helped me replace the neck seal in my dry suit. Apparently adding a latex neck seal to a neoprene suit is pretty common, and it’s an easy process. First, I coated the sealing area with AquaSeal and let it cure, then I put another coat on to adhere the latex. Then I trimmed it and put one more bead of AquaSeal on edges, and the suit was ready to go.

Giving the CWB a lift

On Saturday, I worked with Sterling Marine Services Llc to level out some of the floating docks at the Center for Wooden Boats by installing some new barrels. Once we got we got a system down, it went really fast. Sterling Marine Services Llc has posted more about it in their brand-new blog here.

Repairs and updates on the Island Champion

I visited the Island Champion this week to isolate the overboard through-hull fixture from the engine. This is an area of excessive stray voltage, which induces electrolysis in the surrounding planks and makes them rot out a lot faster – according to our resources, it’s like nail sickness from increased alkalinity.

I installed piece of hose to separate the engine from the through-hull fitting, which disrupts (in theory) the electrical current running between them:

This should hopefully stop the electrolysis and save the hull timber a little longer.

Also, boat buyers take note: the Island Champion is not for sale anymore.

To bond or not to bond

This brings up the age old-argument: “to bond or not to bond.”

To bond, or not to bond: that is the question:
Whether less noble metals should suffer
The slings and arrows of outrageous corrosion,
Or to take arms against a sea of troubles,
And insulate them. To dielectric: to isolate;
No more; and by isolate to say we end
The corrosion and the thousand natural shocks
That hulls are heir to, ’tis a consummation
Devoutly to be wish’d. To dielectric, to isolate;

On the subject of galvanic corrosion: the way I read it, impressed current is best but anodes are easier and more common. If using anodes, quantity and placement are very important to get right and bonding or isolating is addressed on a case-by-case basis.

Some fittings below the waterline, if isolated, can take a long time to degrade, while others will need to be wired to the anode using a resistance-free electrical circuit with heavy-gauge wire, good connections, and keeping it out of the bilge water. When working with mili-volts, a loose connection is no connection: the mili-volt will not jump a gap. I think it is this sloppy wiring that causes bias in our maritime tradesmen.

More important than the bonding and anoding, boats and equipment should be inspected and repaired regularly – and repairs should be made before small problems are catastrophic. It pains me to hear folks argue about bonding while the boat is sinking. While limiting galvanic activity is important – keep it in perspective!

Update on the Maris Pearl

Meanwhile on the Maris Pearl, we’re down to just looking for the shaft that attaches to the piston in the reversing mechanism and the camshaft gear.

Who’s got one? Any drawings? Anything? Help?

Work begins on the Arthur Foss

The Northwest Seaport started their “Stop the Leaks” project on the Arthur Foss; it sounds like the first step was to take off the big rubber fender on the bow. They took a lot of pictures of it – and better yet, wrote a blog about it! Check it out here!

2010 Week 3 in Review

More work on the Maris Pearl

I’m still working on the Maris Pearl‘s reversing mechanism, trying to track down parts for it. I’ve been working with suppliers and calling collectors and engine owners I know who have spares. The Westinghouse controls rarely need attention, so there’s not a lot of information available on these units. It’s taken some extra time to search it out.

Winter Work on the Thea Foss

The Thea Foss‘s twin Atlas-Imperials are getting some attention this winter. The boat’s engineer worked with Dan to remove all the valves, start valves, and injectors out of both engines, then I spent a lot of time this week disassembling and cleaning everything.

As you remember, this process involves disassembling them each, putting them in a solvent bath, flushing the water jackets, sand blasting and another solvent bath, flapper the guide, and wire-wheel the stems.

2010 M4 Party

The big annual art and music event that OTM helps sponsor now has a not-for-profit fiscal sponsor, so make your donations out to Shunpike, with M4 mentioned as the program.

This year’s show will be the 10th annual, on May 1st. The steering committee is planning furiously, and it’ll be even bigger and better than last year (always our goal).

Working on the bow thruster

We got the new parts and tools to fix my good customer’s bow thruster, but still got caught inadequately prepared. I had to run out in the middle of the job to get more parts.

I also had a problem with my dry suit: the neck seal was too tight. Apparently, this can cause Carotid Sinus Reflex, when your neck seal presses against the carotid artery and makes your brain think your blood pressure is too high and lower your pulse rate to compensate.

The symptoms can include nervousness and a shortness of breath, which at the time I attributed to being out of practice from not diving enough. While it is true I am a little out of practice, the nervousness and shortness of breath were actually due to the neck seal. I’ll replace this before next week, in time to dive next Saturday at the CWB.

Despite all this, we still got the bow thruster fixed right up.

Boats for sale

The Pacific Sunrise is for sale. It’s a sweet boat with an Atlas-Imperial 6HM1125 diesel, and is going for $75,000.

The Island Champion is also for sale. She’s a great boat with a Fairbanks-Morse 35F14 diesel.

Bonus! Mention this ad and get a free OTM Inc T-shirt with your purchase!

2009 Week 46 in Review

It turns out you can’t take diesel injectors on a plane. I showed up to Kenmore Air on South Lake Union with three boxes of Washington parts to take with me to the Catalyst in Friday Harbor. I have flown these parts back and forth a few times already, but today the rule is interpreted to mean “any part that might have come in contact with oil is not allowed on the plane.” This would rule out my clothing and possibly parts of me, too, but rules are rules (today, at least), so a drive, a ferry ride, and about six hours later I finally got to the boat.

I installed the injectors first and timed them, so that I could easily clean out the cylinders through the valve cage holes. Then I reinstalled the valves, kerplunking them all for a tight fit.

Once I started up the engine and it was running nicely, I helped Bill deliver it to Jenson’s Boat Works in Seattle. It was a great trip, a beautiful night cruise, but one injector was erratic (sticking open) and the temperatures were going up and down – I’ll look into this next week. I also found two valves leaking around the cage; this will probably resolve itself once the new squishy gaskets I ordered come in.

Other than that, the engine ran great.

2009 Week 44 in Review

Work on the Catalyst parts

This week, I worked some more on the Catalyst‘s parts in my shop. To replace the bent valve, I called up Safety Seal in Texas, since they’ve made valves for the Catalyst before. They happened to have four valves on the shelf from when they first machined them up, five or so years ago. What a deal – I bought all four.

Then, I reassembled the valve cages. Each cage has nine parts (not counting the removable nose that we never take off), and once all the parts are cleaned, assembling is fun and goes really quick.

Then I reassembled the injectors. Each injector has 24 parts, plus an extra packing ring if desired. This time, I installed Viton packing, which will allow biodiesel to be run through the engine. I hope it works.

My River Chronicles: A good read

I finished Jessica’s new book, My River Chronicles. It’s a good read – you should pick it up for yourself.

The book has several stories that take place while running old boats up and down the Hudson River. It’s got great descriptions of how Jessica got to know boats, boatmen (boatwomen), the river, and history, all from the engine control station while watching the dials. Reading it makes me feel like I’m hiding out in the engine room, bullshitting with Jessica and other engineers so we don’t have to hang around deckhands.

2009 Week 42 in Review

New gaskets for the Catalyst

First up this week at Old Tacoma Marine Inc, we ordered gaskets for the Catalyst‘s valve cages from Omni Packing & Seal Co. They don’t many take orders for the “sandwich gaskets,” which were originally asbestos with thin copper shielding surrounding the asbestos, because it takes a long time to make them and they’re expensive and one-time-use only. They are true to the Washington design, though, and they seal really well, so it was worth the extra time and money.

Sending out the guides

The Catalyst‘s engine was originally rated to run at 450 rpm. It’s been overloaded for many years, but now the new owners are committed to returning it to the 1932 specifications. This means unloading the engine to the point where it can be run at 450 rpm without overloading the engine.

To achieve this, it’s best to ease into it by catching up on the maintenance: as the engine is sped up, problems that go unnoticed at 350 rpm become critical at 450. A common problem is too much clearance in the cam follower guides, due from wear. The signal for service due is a knock, made by the follower hitting the guide at cruising speed.

To service the cam follower guides, you send them out to be honed straight and round. Then you have the cam follower (not the roller, but the crosshead like part) built up using flamespray, then ground down to leave .0015″ clearance. Then you put it all back together and start testing.

Suck, Squeeze, Pop, Blow

We got a funny shirt from Whitworth Marine, reminding everyone that all four-stroke diesels need to do is suck, squeeze, pop, and blow.

Check out Whitworth Marine Services, you East Coasters.

Grinding Catalyst Valves

The Shop’s valve grinder machine can handle any valve from Washingon, Atlas, or Enterprise, and seven boring hours later, we have 13 out of 14 Catalyst valves ready to go.

Unfortunately, one valve was bent, which lead to lots of investigative inquiry. It turns out that the valve seat depths vary on the Catalyst from cage to cage. Without getting into blueprints, we chose to make all the cages extend the same length as the shortest one, which was .425″ from the gasket surface to the bottom.

2009 Week 41 in Review

This week at Old Tacoma Marine, we cleaned all the Catalyst parts we pulled off last week. We broke them all down, then put the oily parts in the hot tank with a heated lye solution and an agitator for a few hour. Then we washed the parts off with water and then with solvent, and then some of them got blasted with glass beads until clean and others got wire-wheeled and the brass got polished.

2009 Week 26 in Review

20Work continues on the Arthur Foss

This week, I continued to work on the Arthur Foss‘s Washington, working with OTM’s mechanic Crystal. We started the week with two big challenges to work on 1) make a tool to drive out the very stuck air-start valve, and 2) put the very heavy cylinder head back onto the engine.

I had to make a tool to get the air-start valve out. Back in 2005, during the very first session of Diesel Engine Theory, we pulled all the intake and exhaust valve cages out of the Arthur‘s engine. I wanted to pull all the air start valves in the head at that time, too, but they were really, really stuck. I decided that it would be best to take them out when we had the heads off, but I’ve been really antsy to start getting them out.

The day to get them out came on Thursday of this week, when I got to South Lake Union with the tool I’d made. It’s basically a cylindrical steel punch that I put up against the air start valve on the underside of the cylinder, and then wailed on with a ten-pound sledge hammer. It didn’t budge for a while – long enough that I thought “crap, I’m going to have to cut this [censored] out in pieces,” which I had to do with one of the exhaust valves back in 2005. But then I hit it some more and it finally came loose and popped out of the head, and I brought it back to the shop to clean it up. Whew.

Later in the week, we used a borrowed three-ton come-along to winch the piston back up into the cylinder, then set the head back on the cylinder. The come-along was a really great tool – I want one. I’ll have to put it on the Arthur Foss‘s wish-list, too.

I picked up a bunch more supplies, including water grommet material in two thicknesses. Then, I had to make a lot of calls and fuss over the head gasket because the manufacturer didn’t have the right material, but I finally got it.

There was also a lot of cleaning and painting all the individual parts. We painted the rockers and valve parts the usual Arthur white and painted the exhaust manifold with high-temperature paint. The TAP guys helped out a bunch this week with the painting – thanks, guys!

With all that accomplished, we were all ready for the next class on Saturday! But first…

South Lake Union party

The Friday Lake Union Park Working Group is still doing great things. On Thursday, they had a big party to “roll out” a new planning document that they all worked on. Lots of people showed up to see representatives from every group (like 20!) speak and everyone was really excited. I’m excited too – ten years ago, none of the different boat factions would even have been in the same room together, and now applauding for each other and finding ways to work together. Way to go, everyone!

Atlas-Imperials are not dead

The Puget Sound Maritime Historical Society just published an article in their quarterly rag the Sea Chest titled “The Atlas Imperial Diesel Engine, an Innovative Engine Built in the 1920s”. While this article gives the Atlas-Imperial diesels credit for being innovating and durable machines, the overarching theme suggests that the engines are gone for good.

I disagree.

Old Tacoma Marine Inc is here to show the next generation that heavy-duty diesels like the Atlas-Imperials are alive and well and still working as they were designed to do almost a century ago. The 500 or so heavy-duties from the four manufactures that I like the most are near-evenly grouped into four active categories by use: commercial, pleasure with a purpose, museums, and collectors. In all categories, the engines must function to fulfill specific duties, and these keep a small but diligent group of mechanics, engineers, operators, parts suppliers, curators, grant writers, museum program managers, and grey-haired guys who know everything all gainfully employed year-round. We’re a tight bunch who meet often and share stories and get their own tables at the tugboat parties or tractor shows.

This network of support and the great need for the engines to run is the reason this article is premature in writing of the death of these innovative engines, built to last from the 1920s and far into the future.

Underwater Surveys surveys the Lightship #83

A diver from Underwater Surveys did an underwater video survey of the Lightship #83 this week. He found that the hull is in about the condition we expected, with lots of aquatic growth – so much that it looks like a coral reef. I can’t wait to haul it out and clean all that off.

If anyone needs an underwater survey of their boat, let us through and we’ll patch you through to Underwater Surveys.

Indian Grave #3 running!

This week, I also got word that the Indian Grave Drainage District’s engine #3 successfully ran for about five minutes. I can’t wait to see them all working!

Diesel Engine Theory Session Four

Saturday morning, we all met on the Arthur for part four of the Diesel Engine Theory class. The first task was to move all the parts from my truck back onto the boat. We brought them all to the back deck to sort them out:

We did some more painting and cleaning and sanding, and cut grommets for the exhaust manifold:

We also did some old Diesel Engine Theory standbys, such as the Washington Valve Dance (putting spring retainers on the valve stem), the Kerplunk Test (fitting the valve cages into the cylinder head; a “kerplunk!” sound is good, a “squish…” sound means more sanding), and annealing copper gaskets with heat and then cold water:

Then we had another amazing lunch cooked in the Arthur‘s frying hot galley with the fabulous Chef Kim, who made cheese sandwiches, tomato soup, and cayenne brownies. She also baked lots more of the amazing bread she made last week, and we all had tons of it.

After lunch, we did some more cleaning, then got the rod bearing back in. This was an excruciating job because the rod bearing is two big heavy pieces of metal that fit around the crankshaft. It’s tricky because you have to suspend the lower half while you get the upper half in place and the bolts through. I rigged up some braces to keep the pieces in place, then got into the crankpit while all the students maneuvered the pieces into place.

It was hard work (especially since the boat was hot and the crankpit full of solvent), but we got it done just a little after five. Next week is the last week of Diesel Engine Theory 2009; let’s hope we get it all back together in time!

Seattle Power Tool Races

The power-tool races were Saturday evening. I wish I could have attended. Hopefully next year.

2009 Week 25 in Review

This June is a very busy month for Old Tacoma Marine Inc. Right after last week’s great Diesel Engine Theory class, I got back on an airplane for Illinois.

Back to Quincy

I got back in to Quincy and the Indian Grave Pumphouse to pick up where I left off two weeks ago: setting up the rod bearings on engine three. As always, I spent some time at the beginning cleaning and finding a workspace in all the piles of parts and tools. Once we actually started putting pistons in, though, we got into a good rhythm. I cleaned the bearing, fit the felt and felt springs, and put it onto the journal. Then Keith and Nathan put the piston in on the piston holder tools, then bolted down the head. Then I set the piston height by stacking about ¾ of an inch of shims between the bearing halves and pistons, using a jack to push the piston into the bottom of the head while measuring its travel with a dial indicator. The Fairbanks-Morse manual calls for .125 to .188 of an inch piston-to-head clearance. Using the above method, I could easily set them all at exactly .125.

After that, I set the rod bearing clearance. I pulled out the big stack of shims and guessed at the required shim pack, then I bumped the bearings and adjusted them. The manual calls for zero clearance and good fore-and-aft motion. This is much tighter than on pressure-lubricated bearings like those on Washingtons. The bearings on these Fairbanks only receive a few drips per minute while running, so the bearing needs to be much tighter to create the hydraulic wedge action necessary for it to work.

Now, with this in mind, I did set up the bearings much tighter than the pressure-lubricated rule-of-thumb, but I was afraid to set it all the way to zero. I know that when the book states “zero clearance” they mean “zero with a good film of oil” and probably not with a heavy-duty hydraulic jack pushing up on the bearing and maybe not using a dial indicator measuring to within ten thousandths of an inch.

So, I set everything at .004 of an inch. I see this as fair and might go to .003 if I could be there for the first 100 hours of running.

Once all the rod bearings were finished, we set up the turning tool again to see how smoothly the crank turns. It turns great! Then, we started shooting soda bottles out of the injector holes.

Also, on Wednesday, I had a nice dinner with Indian Graves Drainage District Commissioner Duke and his family. Duke really likes these old engines; he’s telling the folks at Fabius River Drainage District to keep their two 32E14 (6)s. I’m going to keep badgering them as well, and I hope to get a grant to go down and refurbish them, rather than replacing them with new high-speed diesels.

I’m scheduling another trip for July 5th to finish the next two engines.

Diesel Engine Theory Session Three

On Friday night, I flew back to Seattle just in time for the third session of Diesel Engine Theory aboard the Arthur Foss. The next morning, I got up even before the chickens – which is really impressive because Saturday was the Summer Solstice, the longest day of the year.

I stopped by the shop to get it ready for the class, then got coffee, then went to the Arthur to start up the diesel stove for Chef Kim. Then, I went back to the shop just in time. Everyone but Sterling and the three TAP guys (who canceled) were there waiting. We spent the morning cleaning more parts, testing and setting the spring pressure in the injector, and lapping the intake and exhaust valves to their seats.

Just as we were getting ready to head out, 200 naked bicycle riders went screaming by the Shop down Leary. For those of you not from Seattle, the naked bicyclists are a nationally-known tradition that opens the Fremont Solstice Parade (you should Google it). Of course, Diana the museologist and class photographer was in back photographing engine parts or something at the time, so we didn’t get any OTM Inc photos of the bicyclists. Maybe next year.

Just before lunch, we took the air intake manifold to the car wash. I’ve found this is an efficient way to clean large engine parts – it gets all the big chunks of stuff out of the parts, and car washes are all set up to handle diesel gunk, anyway.

With that done, we got to the boat where Kim had the galley baking hot and French onion soup, salad, fruit, and fresh bread, all made on the Arthur‘s diesel oven waiting for us.

It was great – maybe the best lunch ever because of the bread:

We spent the rest of the afternoon cleaning the piston ring grooves and measuring them, then measuring the piston ring gap. I think that many of the students would say that measuring the ring gap was a favorite part of the class because to do so one must get completely inside the crankpit. Wow. Standing in the crankpit, leaning on the crankshaft, and reaching overhead to place a ring in the liner to check the gap is an amazing task for those who do not regularly get into engines.

Then we lowered the piston into the cylinder and set it on the crank to get it ready for installing the rings. That job will need to wait for next week, though.

2009 Week 24 in Review

OTM Inc spent most of this week working on the Arthur Foss‘s Washington, but first:

Update on the Lightship #83

Following our successful preparation of a Preliminary Engineering Report two years ago, Northwest Seaport has asked OTM Inc to submit a bid to serve as project manager for the Lightship Rehabilitation. We assembled our project management team and had our first meeting at the Northlake Pizza Tavern to discuss how to effectively perform the duties outlined by the Seaport. The meeting went well (and it was $2/pitcher PBR night!) and we’ll have the bid in early next week.

More Restoration Workshops?

Brian, the Ocean Bay Marine Inc shipwright and OTM Inc shop partner, has been working with the Seaport on assorted projects since 2007, and he’s really interested in doing public classes like Diesel Engine Theory, only with wood stuff rather than engines. I met with him this week to talk about I got the engine programs up and running. Trouble is, it takes a lot of time and effort to develop programs like this. I told him to be patient and persistent, and offered to talk more any time. I hope he gets something going – the Arthur is a great boat for people to learn on.

Work on the Arthur Foss‘s Washington

The Shop is now plugged with Washington parts from the Arthur Foss. After last week’s exciting Session One of the 2009 Diesel Engine Theory Workshop, I loaded all the parts we took off Cylinder Four into my truck and brought them to Ballard to be cleaned, tested, painted, oiled, lapped, and set as needed. This includes the fuel injector, the intake and exhaust valves and valve cages, about half the intake manifold, some couplings from the exhaust manifold, the rockers and rocker arms, the push rods, and pieces of the water cooling system. Pretty much all of my work space is covered with Arthur parts, but it’s great.

We spent most of the week getting all these parts stripped down and ready for the class to work on. Crystal, OTM’s mechanic, worked with me to clean engine parts, and she also serviced the Arthur‘s generator. I also hired on Sterling the future towboat captain to get ahead a little, since I’ll be heading out to Qunicy again next week.

We also spent a lot of time getting the cylinder head off. Following last week’s class, one of the head nuts just would not come off. We tried oil, fast heat, slow heat, paraffin, and hammers, but it wouldn’t budge – it destroyed two of the output drives for our big torque multiplier (don’t worry Brian, we ordered new ones). Then I talked with Dan, who said to get a slugging wrench from Pacific Industrial Supply (they’re in South Park now). I went and got the wrench and we strapped a comealong to it real tight, then wailed on the wrench with a really big hammer. It finally did the trick – the head nut came loose in about three blows.

Even with all the head nuts off and a serious strain on the lifting straps, the head was not going anywhere. The engine is more than eighty years old and all the minor leaks and corrosion over that time had caused the head to become one with the cylinder and studs. Crystal and I had to use sawzall blades to cut through all the corrosion in the seam, then we hammered dozens of little wedges in to pry it loose.

After a lot of hammering, it finally came off with a little tiny “pop,” and we winched it up. The Arthur has the biggest size of cylinder that Washington Iron Works ever produced. Its cylinders have an 18-inch bore and are really, really big. We estimate the heads as weighing about 2,200 pounds. As we lifted the head off cylinder four, I pictured it as a wrecking ball until we had it secured it to the deck.

After that excitement, we spent the rest of the week cleaning more parts, until…

Diesel Engine Theory Session Two

Early Saturday, the Diesel Engine Theory class all met at the Shop.
We spent the morning cleaning parts using wire wheels, sandblasters, hot lye, needle guns, flapper wheels, belt sanders, hammers and chisels, acid baths, solvent, 409, rags, and fingernails.

At lunch time, we all headed down to the Arthur for hamburgers and salad prepared by chef Kim in the sizzling-hot galley.

We spent the afternoon cleaning the bigger pieces still on the boat. We cleaned the piston with scrapers and flapper wheels, then cleaned out the piston ring grooves using a broken ring with a handle duct-taped to the other end. This gave us a tool exactly the right size and shape to scrape out all the gunk clogging up the ring grooves, and there were plenty to go around.

We also cleaned the threads on the studs that protrude from the cylinder. I decided that the best way to do this was to run the nut up and down the stud using lots of valve-lapping compound. This gritty mixture machines off the rust and dirt and makes sure to keep the threads the right shape. The downside to this process is that it’s painfully slow, but the students all did a great job – especially the TAP guys.

We also pulled out the rod bearing. The babbitt is cracked up, but not too bad considering that it’s been at least 40 years since it was last re-poured (and probably a lot longer than that).

We’re not going to have it re-done this time; a full chapter in one of my diesel repair books is dedicated to running on cracked bearings. It says that as long as there aren’t any holes in the babbitt larger than a dime, you should be okay. The number four rod bearing babbitt is mostly just cracked, with only one little hole that’s way smaller than a dime, so I’ve decided that it’s okay for now – especially since we run the engine so lightly these days We’ll plan on re-doing the rod bearings after we service all six cylinders.

Last and most tiring, we used the ball hone to clean up the liner. It was agony because our ball hone is 16″ and the Arthur‘s cylinders are 18″, so we had to swirl it around to get the liner cleaned and patterned correctly.