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REPORTS ON A 1914 HUMBERETTE RESTORATION


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Now to try and reconstruct the missing and rusted sections of the exhaust system.

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Both the LH & RH exhaust down pipes were rather fragile and needed replacing. I intend to try and reuse the flange section where it bolts to the side of the cylinder barrel.

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I thought this was the safest way to mount the flange in the vice, with 2-bolts, while I heated it up with a big nozzle in the oxygen/acetylene torch. When it was 'cherry red' and the braze had melted, a twist and a tug got the old exhaust pipe free.

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There were only 3-bolts fixing the exhausts onto the engine. One was missing. As you can see there appear to be 2 different thread sizes. I decided to make 4 off new nuts and bolts to fit the flanges.

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I used hexagonal bar for the bolts, the heads are a bit smaller than standard as there is limited room for a spanner (wrench).1108.thumb.jpg.b1ccba7b7c9a4567275417a319243630.jpg

4 new bolts made. Now for the nuts.

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The nuts need to be a large diameter but thinner than normal due to the lack of space.

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Nuts and bolts finished and ready to see if they fit.

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From this photo you can see what I mean about minimal space for the nuts. I needed to mill a little bit of the side of each nut to allow the bolt to go into the nut. At least I won't have to put a spanner on the nut as it now locks itself in position as it rotates.

I will need to make some copper gaskets to go between the  exhaust and the barrel.

 

Can anybody suggest what thickness of copper to use, and the best way of cutting out a gasket in copper? 

 

I have never needed to make a copper gasket on any of my other restorations before.

 

 

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Just ask the www. My first two responses were u-tube videos. Here is the third, although they suggest a different material.

http://www.bertram-hill.com/making-exhaust-gaskets.html

 

In that method, they sandwich the material between two bits of thin plywood and cut the whole lot with a hole saw. Others cut the copper using a scroll saw then anneal it. But they say copper doesn't seal very well?

 

I made one for my Dodge 8. I bought a sheet of grey exhaust gasket material. I can't recall what it was but it was a sandwich of grey-silver(a soft steel mesh?)-grey. I used a drill and tin snips.

 

 

Edited by Spinneyhill (see edit history)
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I need 2 copper exhaust gaskets for the Mitchell. I was thinking of making then by sandwiching pieces of copper between 2 pieces of 1/4" aluminum. I'll probably make 6 or 8 copper gaskets of them because it's just as easy as making 2. Drill the holes for the bolts first...using the bolt holes as a starting point, bore the hole in the center and machine the edges. When you remove the bolts that hold the sandwich together you'll have a little stack of perfect gaskets without any twisting or bends. I think this would be a lot more precise than using plywood.

 

Nice bolts Mike. How did you round the heads? They look exactly right.

 

 

Edited by JV Puleo (see edit history)
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Thanks for the suggestions and help. Now, why didn't I think of that!?

 

I will find some 1/4" aluminium to sandwich the copper sheet.

 

Joe,

We got cut off when you phoned yesterday. We have been having problems with our telephone line this last week. I will send you a PM with daughter, Fay's works phone number, which is at the other end of our barn, in case you have a problem getting through on our phone number.

Mike 

 

I'll take a photo of the lathe tool I used for the bolt heads and post it here next time I write up my report.

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Hello Mike,  The wheels sure look nice and I bet it is a nice feeling to be to the point of rolling your frame around!  Have you had any of you past wheel projects powder coated?  I had a set of 30 x 3.5 Houk Model T wire wheels powder coated.  They turned out very nice but were still a handful to mount the tires.  The thing I like, about powder coating wheels, is the fact that they are a bit more tolerant to "fighting" the tires on with out damaging the paint!  Will you be doing your own tube forming for the exhaust system?  I see nothing wrong, at all, with your wife nudging you towards blue.  It would be boring if we had all our cars painted the same color.  One of my favorite colors is a nice deep rich blue, oh yeah.  Keep up the good work/

Al

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3 hours ago, JV Puleo said:

I lay awake at night thinking up ways to do things like this...and making notes in a big notebook I keep there.

 

In the past when working on projects such as our attempt on the human powered speed world with the 'Poppy Flyer' and our conversion of the Nissan TD27 diesel engine to propane for the 'London black cabs'. I always used to have a note book by the side of the bed, just in case I came up with a 'brilliant idea'. Since being prescribed 'Californian Rocket Fuel' (Mirtazapine) I don't seem to lay awake long enough to have any brilliant ideas!

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1 hour ago, alsfarms said:

Hello Mike,  The wheels sure look nice and I bet it is a nice feeling to be to the point of rolling your frame around!  Have you had any of you past wheel projects powder coated?  I had a set of 30 x 3.5 Houk Model T wire wheels powder coated.  They turned out very nice but were still a handful to mount the tires.  The thing I like, about powder coating wheels, is the fact that they are a bit more tolerant to "fighting" the tires on with out damaging the paint!  Will you be doing your own tube forming for the exhaust system?  I see nothing wrong, at all, with your wife nudging you towards blue.  It would be boring if we had all our cars painted the same color.  One of my favorite colors is a nice deep rich blue, oh yeah.  Keep up the good work/

Al

I had a bad experience with powder coating many years ago in the mid 80's. We patented, manufactured and sold leaning motorcycle sidecars called the 'Sidewinder' under the company name of Freewheel UK Ltd. We had the frames powder coated by a company and found the coating flaked off after a short while in use. We went back to spraying them ourselves. It's a bit like restaurants, you have one bad meal and you never go back there.

I fitted new tyres to the Model T that I had with no problems at all. I think I am just getting old and feeble!

Yes I am pleased with Janes choice of the blue colour. Until I get this big lump of machinery, that has just arrived, onto casters, and moved out of the way I can't move the Humberette chassis anywhere! I hope I can get the casters fitted this weekend.

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It took four fit blokes to drag the pallet into the workshop - I just watched them and I was exhausted when they finally got it inside the garage. It is an old Wickstead 3-phase mechanical saw that I bought on eBay. I have some large diameter steel bar that I will eventually need to cut up to make some bearing parts and gears for the next project that needs finishing, a 1897 Perks and Birch motor wheel tricycle. I forget if I have posted a photo before, but if so, sorry, here it is again.

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It's the same as this, but more a box of bits. The barrel was missing from the engine. I have had a new barrel cast, but there is still a hell of a lot of work left to do to the tricycle. The photo is of Perks, Birch and there works foreman on the machine. They eventually sold out to Singer, or made the Singer Motor Wheel for Singer.  

Edited by Mike Macartney
missing words (see edit history)
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Spinneyhill posted: Just ask the www. My first two responses were u-tube videos. Here is the third, although they suggest a different material.

Thank you for the link you posted. I think I shall use copper and try Joes suggested method. I have saved the link on my computer for future reference. I think it will work OK with thinner or softer material, as shown in the link.

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MAKING THE MISSING PARTS OF THE EXHAUST SYSTEM

 

The late previous owner, so his son told me didn't like the flexible section of exhaust pipes that were on the Humberette so he chopped them out. It has left me to think of a way to remake the front sections of the exhaust. So I decided to buy a selection of some standard exhaust bends to start with. As the engine is solidly mounted to the chassis (no rubber mountings) and the silencer, also has mountings that could be solidly mounted to the fixing points on the chassis, there was no need for the flexible pipework.

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This bit looks as if it will do here . . . .

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I better mark the position. . . .

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This bit of exhaust will fit the existing silencer which seems to be in good condition. . . .

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The right hand exhaust pipe might prove a problem as it has to go under this tie rod from the back of the gearbox to the front axle!

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Now to try and clean up the old braze so the new steel pipe will fit into the flange - easier said that done!

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I measured the length that should fit into the flange. This split you can see in the photo, will hopefully fill with braze when the new pipe is brazed into position.

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I transferred the measurement to the new exhaust pipe to give me an idea as to when it was in the correct position.

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I tried the flange but it needed more cleaning out.

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I put some engineers blue onto the pipe and . . .

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twisted the flange back onto the pipe to find the high spots.

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I found I had got this 'flap wheel' that was just the right size, unfortunately it was only 240 grit so it took some time the wear away the braze so that the new pipe would fit snugly.

 

Yet again, I have got to the limit of photos I can load in one post, perhaps I should make the photos smaller? Back soon!

 

 

 

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I would not mount both the engine and silencer solidly without some sort of flexible connection between them. All of these early cars had quite flexible chassis and the inevitable twisting may stress the exhaust mountings at the engine. I'd want either some sort of slightly flexible connection or, if the engine and exhaust pipe are firmly attached, some sort of flexible mounting for the silencer.

 

That saw is great. If you didn't have one before you will be amazed at how useful they are. I could not do without mine.

Edited by JV Puleo (see edit history)
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Thank you for your advice on the flexibility of the exhaust system. I must admit I had not considered the chassis twist. That is why doing posts on your restorations projects is well worthwhile, as you get helpful advice from others. I will have a look this morning and see the options I have. I think, maybe, the simplest option will be to flexible mount the silencer.

 

I have had a saw before, but it went with Freewheel UK Ltd. when my brother-in-law took over that part of the business. I needed more space at the Cromer site for the BMW 2002 & CS parts business. I gave him the business as long as he moved it to another site. He has since retired and two of the guys that worked for him have taken it on, they seem to be busy, and doing well, with mainly metal fabrication work. I should have got them to do my exhaust! I know that they would have made a better job than I have. They made me some stainless steel rear exhaust pipes for the MGB from patterns I made up in mild steel.

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I think the 1910 Mitchell had all the exhaust parts solidly mounted. When I bought the car, 3 of the 4 flanges on the block that the exhaust manifold attaches to were broken off. I had them furnace welded, re-drilled and tapped the holes and the fact that I didn't do a perfect job led to quite a few of the problems I had making the manifold. I'm reasonably certain that the twisting stress, magnified by the leverage of the long exhaust pipe, contributed to the problem. That is why I made an extremely robust clamp to hold the exhaust tube below the manifold - so that if there is any stress from chassis movement, it will be exerted on the tube and not the manifold.

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Thanks again Joe. I tend to forget that manufacturers were still learning the idiosyncrasies of the internal combustion engine in there 'horseless carriages' at the beginning of the century!

 

I have had a good look at the exhaust, engine and gearbox this morning. The left hand and right hand exhaust down pipes, run by the crankcase to gearbox fixings, as can be seen in the two photos below. I could make some suitable brackets to mount the downpipes to these points which would help take much of the stress off the flanges.

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RH downpipe.

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LH Downpipe.

While I was looking at the exhaust,  I decided to jack up one corner to see how much the chassis may move when one wheel is well off the ground.

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And to also see how much room I had between the tie bar, that runs from the back of the gearbox to the front axle.

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Not a lot, but, as they say "A miss is as good as a mile"!

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Another area I will need to keep an eye on is where the righthand exhaust goes under the gear change linkage. I put the gearbox into third gear, the lowest position of the rod, and marked the exhaust pipe.

I now think it is time for a jolly good clear up before I start making anymore mess.

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What is needed is a good clear up before I do any more work on the exhaust system!

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I started yesterday tidying up some of the bits and boxes I had got out previously, and not put away. With my COPD, I find sweeping up and lifting things very tiring.

This morning I asked Jane if she wouldn't mind helping me with the clear up.

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Like the good girl that she is she came up to the garage and did the sweeping and brushing the spray and grinding 'stuff'.

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What a difference. Thanks Jane. She's one in a million!

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Joe, I got your post regarding - The Book of the Motorcar by Rankin Kennedy. Thank you for your thoughts. For some strange reason your post has not appeared here?!? I tried to reply to your post, but I think the AACA forum site was having a bit of a 'melt down', it said TRY LATER! I bought the initial 3 volumes about 25-years ago. The 4th Volume, was more difficult to find. It was probably 10-years ago I managed to find a copy of that.

 

Jane and I scoured the volumes to try and find anything on the Humberette and found a little information, unfortunately it was information I already new. The indexing of these volumes could be a lot better, although they are very interesting early motoring books and are a mine of information.

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That is strange. Immediately after I posted that, I was unable to get back on to the AACA site to see if it had been posted so I'm at least gratified you got the original message. Yes, those early mechanical books are usually so general in content that it's an act of God if you find some specific information you are looking for but it's always worth a try.

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I did a post yesterday about starting to repair the other rear wing and that has disappeared along with the photos.

Some of the best information I have obtained on the Humberette has been from 

magazines of the era.

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I have just noticed in this article it shows the run of the exhaust system!

I'll have a study of this before I do more on the exhaust system.

 

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STARTING TO REPAIR THE OTHER REAR WING (FENDER)

I have got rather behind with my posts. There are a lot of photos on my computer that are ready to post.

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On this rear wing (fender) I was determined to replace the brass bead that been soldered to the bottom edge, as the one on the other rear wing gave me all sorts of grief.

I made a cardboard pattern of the shape of the bottom of the wing that I had already repaired so, hopefully, I could get them to match.

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So far so good. Now to find some steel rod of the correct diameter for the edge.

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I started by trying to bend the rod to the shape of the wing edge - easier said than done!

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This tool I made helped.

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One part of the existing rolled edge was 'squashed' and needed opening up to get the rod to slide down inside to strengthen the edge.

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By 'poking' a scriber and then a tapered pin punch down the hole I eventually managed to open it up.

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It looks as if I put a slight curve into the rod it may work.

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It did work, and that's as far as I got before the painted body came back from the Jaymic Workshop and I thought I better get on with the exhaust system, so that I could then put the body back on the chassis, ready to take to the coach trimmer at the end of April.

With this wing I will now need to cut out a sheet metal plate to replace the bottom of the wing and roll it over the edge of the steel rod when I have finished bending the rod into the correct shape. I can finish the wing (fender) repairs while the body is at the coach trimmers.

 

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Last Tuesday I had a visit from an American friend I met on this forum.

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Joe Puleo, from Rhode Island, USA,  is on the right in the photo and it is me on the left. Joe took the time out of his UK trip to travel the 5-hours up to Norfolk to visit. I met Joe by following his posts of the work he is doing on his 1911 Mitchell. If you have not seen his posts they are well worth following. His machining work is amazing and he has taught me a lot. As Joe stayed the night we had a very good natter. Many thanks Joe for taking the time to visit.

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It was a pleasure Mike and I got a chance to visit a part of the UK I hadn't seen before. I should point out to the readers that the Humber is in remarkably good, original condition. You can see to look at it that it was taken off the road when only 10 years old. Most of it is "as originally made" with only relatively small traces of ham-fisted mechanics. I think the body restoration is, easily, the toughest part of the job.

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Joe, thanks for those kind words. I hope the journey back to Cheltenham went reasonably smoothly.

 

New pistons for the Humberette - We chatted a little about pistons. One thing I wondered, since you left, is it possible to use 3D printing for making the patterns, rather than the expensive process of having them made in wood? Yours, and others, thoughts would be appreciated.

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Are you sure that you have to get pistons made?  Is there not a size available?  I would have thought there would be a small car or motorcycle near enough the same size.  

 

If you can't get new pistons - assuming you are not aiming at oval ground pistons - I would try turning some on my lathe.  

 

https://www.omegapistons.com/pistons.php

 

(P.S.  I know pistons should ideally be either cast or forged)

 

Ray.

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Thanks for the information and the link to Omega Pistons. At present I am just thinking about my options. I have used and modified various pistons in the past. In my 1927 Humber 350cc motorcycle I fitted a Ford Escort piston. I have yet to take the engine apart to check the condition, bore, pin height etc, etc. I shall do this when the Humberette is at the coachtrimmers, at the end of April, having the leather interior and hood (top) made. Thanks again for your help and advice.

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Just as an aside.  In what can only be described as a co incidence, I have twice now acquired a vintage car with brand new standard size pistons fitted to a clapped out engine.!!  Why do people do this??  In the case of my Austin Seven engine I had it sleeved to fit the pistons.  I was thinking about your car and I am sure you have also considered this as an option.  You may have a bit of luck and find that the pistons only need new rings or if the bores are worn oval and new pistons are not available you might consider sleeving down a size and turn the piston to fit?  Lots of options I suppose but you are more patient than me...I would be itching to get the oily bits.😉

 

Ray.

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When I bought the car, the previous owners son said that his late father had sent the barrels (water cooled) and pistons etc. to a company for inspection and there recommendations. Apparently the company said that the barrels needed reboring slightly off centre, and new pistons would be needed as one of the pistons was cracked. His father was about to get the company to do the work when he died suddenly. The son then got the engine parts back from the company and put the engine back together before selling it on eBay. I did contact the company, but got no reply to my email. I am one of those people that if a company cannot bother to reply, I can't be bothered to give then any work! When I was young, I too would want to get the engine running as soon as I got the car. Nowadays, I have more patience and always leave starting the engine until last, after I have checked that everything is OK with engine. My last restoration was a MGB that I fitted a fuel injected 3.9 V8 into. The engine was out of a badly damaged MG RV8,  after inspection and fitting the engine started on my second try. The first try I had the plug leads 180 degrees out - totally my fault and laziness..  

 

As regards to why people fit new standard size pistons in a worn block, I have no idea. Some people seem to have no common sense at all. Over the years I had had quite a bit of experience with engine building although I am no expert. First of all building a supercharged 998cc racing Hillman Imp engine which we ran in the Players No.6 Autocross Championship, in a Hillman Imp. Next was Formula 1200, Mallock U2 Mk8 that I fitted with an early 1100 Escort crossflow engine. I used flat top pistons and ground out combustion chambers into the flat cylinder head. In the 80's, 90's, I raced BMW 2002's in the BMW Car Club Championship in both standard tii and modified series. One of my last engine modifications was a fleet of 15 London Black Cabs with the Nissan diesel TD27 engine. We modified these diesel engines to run solely on LPG as a spark ignition engine. In October this year it will be 15-years since I retired from Jaymic so I have been 'out of the loop' as they say, as to more modern technology. 

 

My question regarding pistons was, is 3D printing good enough yet for making patterns for castings rather than the old method of wooden patterns.

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There is no question that excellent patterns can be made with 3D printing. If you search on Terry Harper's posts on his Wisconsin engine you'll see some amazing patterns made this way. That said, I agree with R. White that it is unlikely you can't find a modern piston that will work. I am making the Mitchell pistons because they have a very unusual compression height. If that weren't the case, I'd have looked for an "off the shelf" alternative.

 

The reservation about 3D printing is that it can easily be just as time consuming and just as expensive as making the patterns of wood although it may be easier to find someone who can make them. If you have access to a 3D printer, it would be a different story...and would almost certainly be the way to go.

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Hello Joe and Mike,  Pistons are the very heart of any engine for sure.  It may be worth a call to the US company "Arias Pistons" located on the west coast of the US.  I have already been in touch with them to see if they have a forged blank that has the dimensions compatible to finish machine to the size required for my Wisconsin project (same bore and stroke as Terry's Wisconsin only mine is a four cylinder road engine not a six cylinder).  Arias has a huge number of pattern blanks for many different applications.  Yes they do have a blank that will work for my application.  When I am ready, for pistons,  I will be going back to Arias for the finished piston set.  Sadly, we are still dealing with snow and cold here in the western US so I am not so excited to get out and freeze my rear.

Al

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13 hours ago, R.White said:

Seeing as you have the patience you might like to study this.  I am afraid my eyes began to glaze over after a while..... 

 

http://sffsymposium.engr.utexas.edu/Manuscripts/2013/2013-66-Snelling.pdf

 

I don't have that much patience! Like you, after reading that you can produce 'sand moulds' by 3D printing I was interested in reading more. Then my mind wandered off somewhere else, but thanks for the link.

 

Joe, I'll have a search for 'Terry Harper's posts on his Wisconsin engine'. What brought the 3D printing to my mind was that one of Fay's customer's hobby is 3D printing and he likes to make 'useful' things rather than making 'useless rubbish'. He makes them some BMW 2002 interior trim parts that are no longer available. When Fay showed the parts to me I was very impressed.

 

Al, Thanks for the tip on' Arias Pistons', I'll make a note about them for when the time comes to look for suitable pistons. To be honest with you, I can't remember even what bore size the engine is without looking it up. I did read somewhere that somebody fitted Harley Davidson pistons and conrods into a Humberette V-twin engine and it improved the performance no end. How true that is, I don't know.

 

I've gone and bought another machine tool on eBay! I collect it on Thursday, its about two hours away me.

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Nice! It looks to be about the same size as my B&S #2.

As for pistons, my first choice would be to see if there is a modern piston that fits. Probably, you can safely raise the compression ratio a little which will increase performance. I don't know what petrol was like in Britain before WWI but in the US the tremendous increase in automobiles between 1908 and 1914 resulted in lowering the quality of the fuel as the manufacturers rushed to increase supply so c.1910 cars and a little later were purposely designed to use much poorer fuel than you can even buy today.

 

I didn't go for custom pistons for the very simple reason that they would cost more than I could spend. About the only thing I have in abundance is time  & tools so making them was a viable option. If I could have afforded them I would not have hesitated to buy them.

 

As to cam grinding...I do not believe it had been invented in 1914. R. White (above) is correct in suggesting they can be lathe turned. The original pistons would have been round. Cam grinding will do no harm so a modern piston is just fine but if you are forced to make them the lack of it is not a major issue. Personally I favor aluminum pistons in hand cranked cars if only because of the slightly greater clearance needed for expansion. They were known when the Humberette was new. W.O. Bentley had them in his racing DFPs and quite famously informed the War Office of his development at the beginning of the Great War.

 

And...I also like to think far ahead on projects. That way, by the time I get to that operation I've already discarded a number of ideas.

Edited by JV Puleo (see edit history)
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 'Terry Harper's posts on his Wisconsin engine' - WOW

 

I wish I was 50-years younger and had the time to learn all this 'stuff'. I thought being retired meant you had time on your hands! Where has the last 15-years gone? Next month Jane and I will have been married 50-years, no way does it seem that long ago we got married.

 

I looked up the bore size of the Humberette and it's 84mm. It appears that a number of cars and motorcycles had standard piston diameters of that size, so finding a suitable oversize pistons should be no problem. Having a quick look on the internet there now seems to be piston catalogues on line. Previously I have looked through the old paper catalogues of Mahle, KS and AE catalogues looking for suitable pistons. I too am looking ahead as it will be summer before the engine comes apart for inspection.

 

This afternoon I spent most of my time on the computer trying to find the quality of the petrol (gasoline) in the UK before WW1, with no a lot of joy. The problem is you get interested in an article, get side-lined and end up having wasted the whole afternoon. I started after lunch and its now nearly 6pm! At least this morning I got a bit more done to the exhaust system. Inside the old exhaust pipe, that I cut, is an 1/8" build up of carbon on the inside walls of the tube. I have never ever seen that much inside an exhaust pipe before.

 

Interesting information regarding W.O. Bentley and alloy pistons.

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If you have to get pistons made I would recommend Ross Racing Pistons of California. They made up my Olds pistons and they came out fantastic. Forged aluminum, with oversized pins, Hastings rings, and delivered to my door for $830, 3-4 weeks total. Another well known piston manufacturer who is known for their antique vehicle pistons quoted me $1,260 for just the cast aluminum pistons. If I ever need another set made for any car I’m doing, they will come from Ross. My machine shop said they looked as good as any pistons he’s ever installed. 

    While there were other pistons available with the correct bore, none were long enough, nor did they have the pin low enough for the Olds. If you have an original, they simply copy it to the correct bore dimensions you need. Just another option.

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It isn't really a matter of how the car runs on modern petrol. They all run better.

The poor fuel sold just before WWI resulted in lower compression ratios than were otherwise necessary so it is reasonable to raise the compression ratio slightly. That will increase power and performance and is more in accordance with current octane ratings. This is just a guess but I suspect the original compression ratio was in the neighborhood of 3.6:1 to 4:1 while a ratio of 5:1 is within reason, especially if the iron pistons are replaced with aluminum. This was all understood at the time but the makers had to accommodate the lowest common denominator when it came to fuel.

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'A vast amount of research has been carried out on all aspects of petrol by a chap called Paul Ireland here in England.  I recommend you sign up to the free on line magazine 'Totally Type 2' which although MG oriented has much of general interest.  I can't reproduce the superbly researched and illustrated articles here as it is copyright but from issue 2 October 2010 onwards, Paul and his team at Manchester University discover some remarkable facts about petrol.  Admittedly, the engine they use for experiments is the MG XPAG unit as found in the 'T' types which is relatively modern in comparison but the information is mostly relevant. 

 

Ray.

Edited by R.White (see edit history)
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