CycleKarts GB

Forums => Build journals => Topic started by: RhysN on 27 Jun 21, 11:45 am

Title: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 27 Jun 21, 11:45 am
A little history first.
Before I immigrated to the UK in 2016 I had an exploratory trip in 2015 (via Tieton) to see if we really wanted to come and live here. One of the visits I paid was to Brooklands where I met with some senior staff and we discussed whether Cyclekarts might be allowed. They were enthusiastic, especially if some were inspired by the cars that ran there way back when.
Subsequently I met with Wes Raynor of Mardave radio controlled cars, who had also built the Darracq T700. He and Bill Alexander were, to my knowledge the first builders of Cyclekarts in the UK. Wes was very keen on doing something at Brooklands, so again I contacted them. Although the circle of known Cyclekarts was small they were keen, but asked if we could delay until there was a viable group.
Thanks to Graham Appleyard and Stefan this long dreamed event is taking place.
One of my dreams for Brooklands has always been a Parry Thomas "Flatiron", or as he called it "Thomas Special 2", as the event is the 95th Anniversary it seemed only right to me that I should now do a build of his car. He had 3 entered for the event 95 years ago, only 2 were finished (in the week leading up to the event). As might be expected they did not do overly well, midfield at best, largely due to a lack of testing it's thought.
Sadly he perished when Babs crashed (no it's now proven he was not decapitated by the chain). That meant the cars were never to really get the fine development they deserved, although they later were seen as good cars.
On to my build.
This is being built as a plywood monocoque, very limited steel. The main body as in the photos is 9 mm ply (£23). Initially it was going to be limited to 2400 mm long (as per the original Stevenson suggestion on length) with the tail truncated some, but as Adrian paid a rush visit the other day it as his first comment was that it looked wrong, I will be making an extension to more correct the long tail look. He we are 3 days in, front axle done and ready to bolt in, rear axle made up and almost ready, 4 wheels  (thanks Adrian) prepared and ready.

The task today is to progress the body top at the front, How to do this has been a sticking point for a long time. Current method is to laminate in fibreglass the round edges and bond to a top, wait and see! (At least I know how to fibreglass!) I can't add the horizontal bulkhead nor the verticals, I'm out of epoxy till Tuesday otherwise the structure would be complete today!
Title: Re: A car for Brooklands.
Post by: Marek.Z.N on 27 Jun 21, 12:26 pm
Very exciting indeed Rhys!!! Fast progress too. Brooklands is going to be great event. I need to speed up my kart for that as I believe a Delage 15-S-8 won the first grand prix there. An interesting car to try and replicate and a good back story. Keep us updated!
Title: Re: A car for Brooklands.
Post by: RhysN on 27 Jun 21, 02:14 pm
To be clear, not REPLICATE, inspired by! Yes, the first winner is the Delage gifted to the museum.
Well to be polite today has been a bit of a "Hands up". I over bent the mould for the side rolls, and then ran out of polyester as well. I need to redo the rolls. Bugger.
Must be time to start the humps!
Title: Re: A car for Brooklands.
Post by: RhysN on 28 Jun 21, 05:57 pm
Well, I woke to the news this morning that I'm self isolating again, as this time it's my daughter in law that has tested positive, and we had a gathering last Tuesday. That does give me time in the shed, but I can't go out to gather materials, even when it's planned for collection.
Epoxy arrived, so the bottom seam of the tub is done, as is the axle mounting area. That's all done with laminations of biaxial glassfibre, and triaxial around the axle positions.
I made a start on hacking foam for the rear deck too.
Yes photos for proof will be forthcoming tomorrow.
Title: Re: A car for Brooklands.
Post by: RhysN on 29 Jun 21, 06:11 pm
More stuff bonded in, and a front "fairing" made. 
Next step is to mount the entire front end.
There are complications! Right now I have to self isolate until midnight Saturday. My daughter-in-law tested positive so as we had a gathering last week we are on the "don't leave the property" rules. I will run out of epoxy brushes!
Also the working space in "Grumpy's Garage is limited, The 1934 Morgan and 72 Peugeot 404 estate projects use up most so all I have is about a metre by 3. Neither of those can be moved. Yes, tight, but at least I'm showing you don't need a big workshop to build a cyclekart :)
Title: Re: A car for Brooklands.
Post by: RhysN on 30 Jun 21, 10:26 pm
Today I was bit distracted as I had some real work (from home) and did another task for the Beast of Hinckley. I did make up all the bits to mount the front springs, axle and such. First error discovered, but easily corrected as the holes for the tie rods are in the wrong place. They are now re cut and fillers for the wrong holes made.
If I could go out the gate I would be mounting the engine and rear axle tomorrow.
Title: Re: A car for Brooklands.
Post by: RhysN on 01 Jul 21, 05:56 am
Nobody has asked, but.. Why choose this method of construction?
My first CK was built in the true Stevenson method. Plywood "tub" with steel rails bolted on the outside to fasten things to, and was very stiff. When I first went to Tieton I was immensely impressed by many of the builds, the ones with a chassis and body bolted on didn't impress me as it was very easy to see the structure twisting. One very impressive car was the "Blower Bentley", totally 6 mm plywood with only very small pieces of 16 gauge where loads had to be spread. On return to NZ I started my Austin 7 build,  for the "Great Austin 7 build off" www.cyclekartclub.com › forum › the-great-austin-seven-cyclekart-build-off. As with a number of my builds I had a visitor who asked if I would sell it, and yet another of my unfinished projects left me. I don't know what happened to it, although someone did say it was on display hanging from a wall somewhere as "art".
I have tried all sorts of methods, in the case of the Flatiron it's because I had under 7 weeks from start to the deadline event, I can do this quickly, I don't weld, it's light, stiff and I can do a bit at a time between work tasks (technically I work 5 days, 4 hours per day but I'll answer phones, emails and such 24/7 to keep the business as efficient as I can).
I'm not saying it's the only method, but in this case with the large cross sectional area it's one that should work for me. If it breaks after Brooklands so be it, it's only being built primarily for the one event.
Title: Re: A car for Brooklands.
Post by: RhysN on 03 Jul 21, 05:22 pm
Front end all mounted and working today. Yes the springing method is a bit odd. There are reasons, ask if you want to know!
Title: Re: A car for Brooklands.
Post by: Marek.Z.N on 04 Jul 21, 11:31 am
For driving upside down ;) ? Tell us...
Title: Re: A car for Brooklands.
Post by: RhysN on 04 Jul 21, 11:46 am
At least somebody asked Marek, I was wondering if it was worth posting anything!
The springs are mounted that way (reverse arch) to get them low enough. The shackles are at the front, I moved them from the rear mount as when I flexed the springs I noted decreasing castor. As I will start with not a huge amount the castor was going to neutral, or maybe negative, and I don't fancy shopping trolley steering characteristics.
If it gets the car running for Brooklands, "Ittledo"
This car is being built from "stuff" I had here which nobody wanted. (Reasons of cost and to be able to move ahead, hence the axle which was built for the unfinished Napier.)
As you can see the space issue is dominant. I now need to turn it round to work on the motor and rear axle installation, I have no idea at all how I'm going to get it out of "Grumpy's Garage" except dismantle almost totally then re-assemble elsewhere.
Title: Re: A car for Brooklands.
Post by: Marek.Z.N on 04 Jul 21, 02:57 pm
Is there a reason the centre of the axle bends down in a v the way it does? I am assuming its how it looked on the inspiration car of the Napier you were talking about to get out of the way of a starter handle or something like that?
Title: Re: A car for Brooklands.
Post by: RhysN on 04 Jul 21, 05:28 pm
You got it one Marek. The original Napier looked pretty much like that.
A later thought! If this was going to be a car for more than the one day it would get a revision of the front suspension. At this point it's specifically for August 7th 2021.
Title: Re: A car for Brooklands.
Post by: RhysN on 05 Jul 21, 01:54 pm
Lunchtime from work I got this ready for paint.
Title: Re: A car for Brooklands.
Post by: RhysN on 07 Jul 21, 06:06 pm
Update as of today. I have a month till it has to be on site.
Title: Re: A car for Brooklands.
Post by: RhysN on 13 Jul 21, 08:25 am
I've made progress on the bodywork. The front is, so far, a skin of very thin ply (thanks Adrian) which will soon be coated with a layer of fine weave glass cloth. Obviously the front needs trimming and the fairing hump in front of the dash being made.
The nose piece should have the mould taken off in the next 2 days to make a fibreglass version, the Jelutong one is heavier than needs be, and not as aesthetic as I want.
The left hand side of the cockpit opening is now ready to attach, 1.2 alloy with a wired edge. Only really 1.2 because I have some spare bits, and one was the right size. If I was buying in it would be 0.9 mm. I had to anneal it (1000 grade) to bend it round the handy former (light pole outside my back gate).
Also in the photos showing my work space for this thing, says he donning the hair shirt.
Title: Re: A car for Brooklands.
Post by: StefanN on 13 Jul 21, 10:09 am
Great progress Rhys - looking forward to seeing it.
Title: Re: A car for Brooklands.
Post by: RhysN on 13 Jul 21, 01:30 pm
As long as epoxy resin doesn't run into supply issues , I'll be there. Thanks Stefan.
Title: Re: A car for Brooklands.
Post by: RhysN on 14 Jul 21, 06:47 pm
I made the mould for the front end today, and sat the thing outside in the sun.
This is ride height.
Title: Re: A car for Brooklands.
Post by: Graham Hill on 14 Jul 21, 07:23 pm
Rhys, when did you master invisibility? !!!
Title: Re: A car for Brooklands.
Post by: RhysN on 14 Jul 21, 08:01 pm
Rhys, when did you master invisibility? !!!
It came with those shoes. You didn't know I had been at Stretton did you? I heard what you said about me :)
Title: Re: A car for Brooklands.
Post by: TopTech on 15 Jul 21, 08:06 am
Is it just the photograph that makes it look long? Add the tail and what will be the overall length when finished?
Title: Re: A car for Brooklands.
Post by: RhysN on 15 Jul 21, 02:18 pm
It should have a long tail, more than I'm initially planning. Right now it's at 8 feet which was the initial guideline way back when. To be  more in keeping with the  look it needs to be a foot longer. Right now the extension is a lower priority!
Title: Re: A car for Brooklands. Thomas Parry Flatiron
Post by: RhysN on 18 Jul 21, 07:53 pm
Well, what a last few days. I painted the Jelutong radiator surround with 2K paint, carefully waxed etc and laid up the mould.  I did work in the fibreglass industry so I don't usually have issues, BUT the polyester interacted with the 2 K. I've never had crocodile like this no matter how badly catalysed resin has been. A huge amount of  work that I didn't need. Now I'll just have to wait and see how the first (and only I hope) shell from the mould comes out.
On a positive note I have the bonnet top ready for the final 200 gm/m2 glass cloth. The "hump" is now shaped, and one layer of cloth done. Inside it has pieces of biaxial cloth to stiffen the 1.6 mm ply wood. When the next delivery from East Coast Fibreglass arrives I'll be doing that. Then the tail, and I'm not looking forward to this. The mechanical bits won't fit, so there are some compromises I'm not entirely happy with. So be it.
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: Marek.Z.N on 19 Jul 21, 07:49 am
It looks cool! what is crocodiling? and what can be done to avoid it? ( soon i will be doing some fibreglassing for the delage
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 19 Jul 21, 04:19 pm
Crocodile, or alligator is a wrinkling of the item being either made into a mould, or later on taken from the mould. It's usually created when the  gelcoat is not properly cured before laminating. That can be avoided by;
1 mixing catalyst and gelcoat very well, usually a higher rate of catalyst in gel ,compared to laminating
2 Leaving the gelled surface to cure well (ie don't rush leave longer)
3 Make sure the gelcoat is cured, nothing on your finger tip, white gelcoat try writing with a ballpoint pen

In this case rule 2 above wasn't totally done BUT the gelcoat reacted with the 2K paint I used. I suspect both factors are involved. Plan ahead!
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: Marek.Z.N on 19 Jul 21, 06:14 pm
Sounds simple enough to avoid now that I know how to :)
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 19 Jul 21, 09:05 pm
After over 20 years in the industry if I can make basic errors, I am sure you might find some too :) In the case of the 2K interaction I found something I hadn't come across before.
 I'll find a decent link for you Marek. IMHO there is a lot of rubbish stuff promulgated on Youtube on 'glassing, and a reasonable amount of good advice too. Despite being an Australian :) this guy makes sense.  https://www.youtube.com/watch?v=PdaX4aA2cY8
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 27 Jul 21, 07:50 am
There has actually been some progress, despite my having lost some of the will.
As I have said before, compromises are needed, t's a stupid build being so confined in the rear. As a result, and also due to not ever likely to be used in the manner of a cyclekart which I espouse the drive is going back to a centrifugal clutch (horses for courses). I'm using 219 chain to get the sprocket size down so it will fit more closely in the rear.
The final moulding for the front has  come out OK, bump on the cowl nearly ready, bonnet fitted.
I'm waiting for UK customs/UPS/Royal mail to deliver the steering wheel which I used on my Voisin C6 at Tieton to arrive back so I can finalise the steering column mounting. The rear cowl/headrest fairing is a (very) rough shape. Final shaping wil depend on the lump going under it being sorted.
As can be seen  I spent money at the local Barnados, £3 for the two bonnet straps. Useless fact, bonnet straps were compulsory at  Brooklands before the can and fishtail were mandated!
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: Marek.Z.N on 27 Jul 21, 09:38 am
It looks great so far. £3 for 2 bonnet straps sounds like the deal of the century!!!
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 27 Jul 21, 10:20 am
Charity shops  are good. Wait till you see the Edwardian and "acquired" bits!
Skips and damaged materials from building sites are  good too. Keep those costs under control :)
As a side line I purchased some of the foam insulation board from Wickes (cheap because a damaged corner) hacked to shape for the rear cover and polyester does not stick to it so easy extraction of the shape! No need for foil, or any of the other things folks suggest! It shapes very well too.
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 28 Jul 21, 01:28 pm
Not a lot done in the last few days, I actually do have to work, if only part time, and yesterday was assisting Adrian with his creation.
However what I reckon must be  the most travelled steering wheel in the world for a cyclekart arrived, so there is work to do. This was originally waterjet cut in NZ, then came with my suitcases when I moved to the UK, wood added and painted here, then went with me to Seattle where it was re-united with the  Voisin build for Tieton, and has now winged it's way back to the UK, now to go into the Flatiron, this afternoon so that will be the steering sorted.
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: Adrian on 30 Jul 21, 07:47 pm
Lets see a shot with the wheels on. You can see just how low it is then.
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 30 Jul 21, 09:08 pm
Lets see a shot with the wheels on. You can see just how low it is then.
As you know  Adrian, there is no room in the workshop for the car with wheels on! An earlier photo with one wheel was indicative.
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 31 Jul 21, 06:15 pm
Today there was progress, at least a glimmer at the end of the tunnel.   As I have said there's almost no room for a brake under the tail, so it was make a mounting bracket to go outside, and a pedal assembly to go inside/outside. Damned near a full day!
I have tyres mounted, rough as gutz body about to get paint. Will I make it?
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: Marek.Z.N on 01 Aug 21, 10:38 am
I hope you make it!
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 01 Aug 21, 12:35 pm
Front springs back in, brake pedal mounted, bracket ready for my friendly welder, and first coat of undercoat today. The tail is still a maybe. Many of you will know my views on tails, so I feel a bit hypocritical if I don't have one. Or a lot hypocritical.
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: Adrian on 01 Aug 21, 02:54 pm
Thereby hangs a tale. :>)
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: Marek.Z.N on 01 Aug 21, 06:38 pm
is the question of no tail due to time or due to space?
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 01 Aug 21, 07:04 pm
All of the above Marek. I have a lumpy bit of fibreglass which needs holes or the sprocket/platewheel, and also a quieter muffler/exhaust to be  a reasonable sound level.
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: synthpunk on 02 Aug 21, 10:29 pm
Ive hung off commenting till now cos I really wanted to see how someone else’s wooden chassis kart was all coming together first before piping up…

I think its looking great!  ;D

Proper lightweight. Simplicate & Add Lightness, and all that. Ive been getting bogged down in fiddly woodwork on my cold moulded tailcone for the Riley, trying to keep the framework rigid, so the bendywood stringers don’t end up distorting it during fitting up, but also lightweight… next time I think ill go down the foam and glass route like everyone else, and save a couple kilos weight and probably several dozen hours of build time .. ;c) I reckon yours will definitely pip mine for lowest weight and probably for lowest CG & ride height too

Nice one Rhys, cant wait to see you on the 7th!
All the best,
Rich
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 03 Aug 21, 08:14 am
To be brutally honest Rich I am very unsure about chasing the Holy Grail of low c of g. I know this is at odds with what most people say, but it comes from knowing that the best handling CK I have driven, out of at least 30, does not have that. More attention paid to other factors. My theory, which aligns with writings of  Costin and Phipps, Arthur Mallock, Alan Staniforth etc relates to c of g and roll axis.
Anyhow, that was not in the raison d'etre for this car, but it is low!
Here are some more pics, a bit obvious what they are! I'm not a fan of the gold wheels, I'd rather they were black, but :)
Title: Re: A car for Brooklands. J G Parry Thomas Flatiron
Post by: RhysN on 05 Aug 21, 09:22 am
Last night was supposed to be my self imposed "if it isn't done by now I'm not going"  deadline. SWMBO has told me I have to.
Fuel tank has arrived, small plastic pitbike unit which will limit running time before refuelling, but solves a lot of other issues as it can be  mounted for gravity fed.
Nobody has asked why I consider this a stupid build, so I'll offer my thoughts.
I'm totally happy with build method (so not a stupid one)
I decided early on that most of it would come out of one sheet of plywood. That compromised the height. I should have narrowed the  floor and given the sides another couple of inches each. Stupid
I didn't think enough about packaging the engine/driveline so have had to revert to something I don't embrace, centrifugal clutch and gear as low as I can. Stupid
Front end using bits  from other incomplete builds is an "Ittledo" A build from scratch would have been done differently. 50/50 on this.
Self imposed time limit is a bit of an issue. I have struggled to remain motivated. Work and giving up days to other things (selling and buying cars, collecting bits for full size projects, helping others etc) has not helped.
Anyhow, there is today (and part of that has just been taken from me by her indoors) and tomorrow for a couple of hours after work before I need to load up and travel, that's it.
It is what it is.

Just thought of the most stupid thing I've done with this, post on the other cyclekart club forum, I should have known I would get slammed for a build that wasn't done with a full workshop, paint booth, Tig or better welding and a car that wasn't known. I should have taken 7 years too.