Still progressing.

February 25th, 2014

Let’s see, been a while since I updated. Not from lack of doing things! Just lack of time to write them up. That will be rectified after this week due to me hating my job, resigning and deciding to take a few months off so I can work on various projects at home!

The floors are now painted in black enamel paint. Just finding that was a pain. I had to go to three local paint places. They all seemed to think I would need acrylic enamel and have to use an undercoat. In the end I found somewhere where I could get a tin of plain old black, oil based enamel and I just slapped it on the floors. Each coat took 16 hours to dry before re-coating so it was a coat a night for a week, 3 on the underside and two on top. Hopefully over time the top gets a nice worn patina with some wood showing though underneath! One trick, that’s probably obvious to everyone else but new to me, was to drill a hole through the paint brush so I could put a rod through it and hang it in a jar of turps so the bristles were hanging free. I was able to leave the brush like that all week just soaking in turps and it was ready each time I needed to do another coat. The other trick is when you take the lid of the pain can you drill four holes in the bottom of the groove the lid fits into. That way any paint that gets into the lid groove just drains back into the tin but with the lid on the tin is still sealed.

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I also finished dismantling and cleaning the gauges and also the key switch. The gauge faces and needles were cleaned carefully with a little soapy water. Very, very gently. The oil gauge needle had no paint so I gave it a very light touch up with some off white. I replaced the blue plastic rings inside the gauges with new rings made from strips cut from plastic drinks bottles and glued with UHU glue. Hopefully the glue holds as that plastic is tricky stuff to stick together.

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The key switch I took apart using this page as a guide:

The only trick really is the nut that holds the switch barrel in place is soldered on. You need to heat it up and suck off the solder (with an electronics solder sucker or braid) then you can undo the nut. I stripped the switch, bunged all the bits in the ultrasonic cleaner then reassembled it all using a little electrical contact cleaner/grease on the switch parts and the smallest touch of graphite powder in the key switch. The markings on the plastic ring that show the switch position had rubbed off in the 1 and 2 positions so I carefully drew them back on with a sharpie pen!

I was going so well with taking apart, cleaning and reassembling I even took apart and cleaned and fixed my broken egg timer!

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After replacing all the plastic rings allowing the gauges to be lit from behind I realised the oil pressure gauge doesn’t have the window! So will will add some kind of dash front lighting or map light. The oil pressure gauge is probably the most important gauge there.

The other thing I have been doing is working out how to install and drive the supercharger. The plan is this. The drive is taken off a V belt pulley on the front of the crank. That runs to the left of the engine to a pulley on a short jack shaft. I will use a 1:1 ratio there. I am using old alternator pulleys. A local auto electrician let me rummage though a box full of old pulleys and grab what I wanted for a few dollars each. The ones I have are about 80mm diameter. I really want some slightly smaller to have more clearance around the belt. Using an A section 13mm belt the smallest you can go down to is about 80mm but if you use a V belt with a notched inner (I don’t mean a toothed belt here) you can go smaller. I do have some smaller pulleys that take a smaller belt (a Z size?) but I don’t know if that will take the power I need. Unfortunately I don’t know what the power I need is! I do know an standard A size V belt should work though so I will stick with that and that’s also what is used on the the blower pulley.

To get enough clearance I will need to remove the cam pulley to the fan but hopefully I can run a new belt to the fan off the crank somehow (and use the reverse direction fan blades). The jackshaft is mounted so it can slide in slots so I can tension the primary belt that way. On the end of the jackshaft is a larger pulley that takes the drive up to the blower which will be mounted on a plenum chamber made from steel box section mounted level, more or less, with the head. Two short inlet pipes will send the mixture into the ports on the block. Straps will support the top of the plenum by hooking onto extra long head studs. On the plenum will be mounted a sneeze valve in case of backfiring. The carb is a downdraft which will mount directly on top of the blower. Because I haven’t done the usual Austin 7 special thing of chopping the nose down I have plenty of vertical height (although I might still add a bulge to the top of the bonnet above the carb just because! To tension the secondary belt I will use another pulley on an arm that rotates around the jackshaft and then gets locked via a bolt into a fixed plate. According to the various V belt design guides online (Gates and Mitsiboshi have good guides) an inside idler is best and it should be put closer to the large pulley on the slack side of the belt. I am getting a pulley identical to the drive pulley on the blower to use as an idler. The larger pulley will be about 120mm which will give me a boost close to 7 PSI.

I have mocked it all up in wood for now just to see if this will even work. It looks right. The wooden plate on top of the head is only there in the mockup to hold the blower up. In practice the plenum will be attached to the block via it’s inlet tubes and also be supported by straps attaching to the head. I am hoping to get someone who knows what they are talking about to look it over and see if it looks sensible! perhaps I can put the whole lot in the boot of the MG and take it down to Hampton Downs for the Roycroft in a few weekends time.

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In the photos you have to imagine the firewall in place. That comes right to the back of the block more or less so with the blower installed the engine bay should look nicely balanced. I don’t just want this to work, I want it to look nicely engineered too! The wooden stick above the blower represents the height of the carb. There is a good inch or two of clearance to the bottom of the bonnet.

Last weekend Joss visited and had his boys with him. The youngest saw the mini bike I started making years ago and never finished and his little face lit up. Since one of my plans when not working is to clear the garages out and get rid of unneeded things I gave it to him so they can finish it off. On Sunday I went to see them with a box of extra bits and the bike is sitting on the bench ready to be worked on.


Joss also had a new vehicle to restore. A truck!


He rescued if off  a scrap pile. It’s obviously a home made toy but it’s nicely done with a steel chassis and a lifting tray. The timber needs some work so we took all that off so Joss can repair it and strip off the pink paint (there is original red underneath). Meanwhile I took the chassis home and stuck it in the molasses tank to de-rust it.

While there I also raided some parts. A nice old Shell petrol tin. The plan is to have a smallish tank, 3 or 4 gallons, then for touring I can carry the extra 2 gallon tin in the boot. The tin was carefully washed in soapy water then I just rubbed it over with fisholene to stop it rusting.


I also got a starter cable (helpfully marked with ‘Starter Pull’) which I will mount next to the steering column on the bracket that clamps that to the frame. I got some small steel offcuts to make a new bracket large enough to hold it


The frame is now sitting back on the chassis loosely. I will attach the floors soon and also need to paint and mount the transmission tunnel. Before doing that I need to cut the little hole that allows access to the torque tube greasing point. I will also steel bash the right kind of door to cover the hole. Well, will give it a try anyway!


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