Author Topic: 15cc Seal and 30cc Seal Major  (Read 30003 times)

Offline Jasonb

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Re: 15cc Seal and 30cc Seal Major
« Reply #105 on: July 09, 2019, 01:15:19 PM »
Can you get the wrist pins in from below? Big ends don't look like they will fit down the bore so you would need to fit the conrods after the pistons if fitting them from above. probably easier to fir rods and pins and then poke the lot in from below.

Personally I like to get all the conrods and crankshaft fitted to see how things turn over before fitting the rings as you can feel for any tight spots which the friction of new rings can hide.

Offline Jo

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Re: 15cc Seal and 30cc Seal Major
« Reply #106 on: July 09, 2019, 04:14:57 PM »
The conrods are long enough to poke through from underneath and to fit the gudgeon pin into the piston above the top of the cylinder and then draw it all down onto the crankshaft.

Jo
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Offline Jo

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Re: 15cc Seal and 30cc Seal Major
« Reply #107 on: July 11, 2019, 11:10:39 AM »
I opted to make a couple of tapered guides to enable the pistons to be fitted with their rings into the liners. They are about half the length of the pistons and when you poke the piston through they close up the rings.

But I still broke a ring  :toilet_claw:

Jo
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Offline Vixen

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Re: 15cc Seal and 30cc Seal Major
« Reply #108 on: July 11, 2019, 11:42:30 AM »
They all look nice and snug. Hope you end up with two pistons up and two down, rather than all in a straight line :Lol:

What type of CI did you use? Continuous cast or centrifugal cast?

cheers

Mike

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Sometimes, it can be a long and winding road

Offline Jo

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Re: 15cc Seal and 30cc Seal Major
« Reply #109 on: July 11, 2019, 11:54:35 AM »
Thanks Mike  :)

What type of CI did you use? Continuous cast or centrifugal cast?

I am using some of that very nice centrifugal cast that our supplier acquired in 29mm sticks. He started off with 10s of feet of the stuff but has much less these days  ;)

Jo
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Offline Vixen

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Re: 15cc Seal and 30cc Seal Major
« Reply #110 on: July 11, 2019, 12:09:43 PM »
Sounds like some very good stuff from your supplier.

I am looking for some 45mm diameter centrifugal cast for the Jupiter. Two compression and one oil control ring per cylinder, that's a lot of rings and CI.

What technique did you use to  trepan out the centre of the bar, so you could reuse the remaining CI for smaller engines?

cheers

Mike
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline Jo

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Re: 15cc Seal and 30cc Seal Major
« Reply #111 on: July 12, 2019, 11:20:45 AM »
Hi Mike, I have tried using various tools but things like hole saws will not let you get very deep. I have a number of specially shaped HSS tools but loose about 10mm on the diameter if I use those  :-\


About this point a set of connection rods would be useful  :thinking: The Seal came with 7 Ali rods, actually 4 match, 2 are suspect and one is totally different  :headscratch: . The Major came with 4 Bronze rods.

The starting point is to put in the big end bolts: The drawing for the major shows 5BA bolts, which we all know are like rocking horse do-dahs to get hold of so I will be using 1/8 Whit cap head screws. The Seal shows 8BA but I only have slot headed screws which is not a good idea .. I wonder if I can get hold of M2.5 Cap heads.

Jo
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Offline Bluechip

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Re: 15cc Seal and 30cc Seal Major
« Reply #112 on: July 12, 2019, 11:38:35 AM »

I wonder if I can get hold of M2.5 Cap heads.

Jo

Ho Yus

https://www.kayfast.co.uk/view-product/SOCKET-CAP-SCREW-DIN-912-HIGH-TENSILE-SELF-COLOUR

Not uncommon actually   :ThumbsUp:

Dave

PS  In fact, I think I might have some ....  :headscratch:  What length are we looking for ??? ... Well, you ... I suppose.  :)

PPS A quick shufti reveals I have M2.5 10mm & M2.5 x 12mm
« Last Edit: July 12, 2019, 11:47:14 AM by Bluechip »

Offline Stuart

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Re: 15cc Seal and 30cc Seal Major
« Reply #113 on: July 12, 2019, 11:50:58 AM »
Another source of small fasteners

http://www.modelfixings.co.uk/index.html


Do small quantity’s as well

No affiliation just a satisfied customer

Worth a look for small bearings as well
My aim is for a accurate part with a good finish

Offline Jo

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Re: 15cc Seal and 30cc Seal Major
« Reply #114 on: July 12, 2019, 12:01:39 PM »
10mm or 12mm long would be perfect  :)

Jo
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Offline Bluechip

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Re: 15cc Seal and 30cc Seal Major
« Reply #115 on: July 12, 2019, 12:31:38 PM »
10mm or 12mm long would be perfect  :)

Jo

How many of each ??  When do you want them?

Dave

Offline Jo

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Re: 15cc Seal and 30cc Seal Major
« Reply #116 on: July 12, 2019, 12:43:43 PM »
Thanks Dave,

I need 8 for the Seal rods plus some spares in case the Workshop gnome gets back from the cricket world cup and takes a shine to them  ::)

No great rush but it would be nice to have them to make the rods with  :)

Jo
Enjoyment is more important than achievement.

Offline Vixen

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Re: 15cc Seal and 30cc Seal Major
« Reply #117 on: July 12, 2019, 12:56:15 PM »
Hi Mike, I have tried using various tools but things like hole saws will not let you get very deep. I have a number of specially shaped HSS tools but loose about 10mm on the diameter if I use those 
Jo

That's more or less I have found. I had hoped you would have a method to reliably trepan a couple of inches deep from both ends of a CI bar.

Anyone else have any good ideas?

Cheers

Mike
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline Bluechip

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Re: 15cc Seal and 30cc Seal Major
« Reply #118 on: July 12, 2019, 01:28:38 PM »
Thanks Dave,

I need 8 for the Seal rods plus some spares in case the Workshop gnome gets back from the cricket world cup and takes a shine to them  ::)

No great rush but it would be nice to have them to make the rods with  :)

Jo

Rightey-Ho  Sarge ....   I have bagged up [ 20 off]  each of the following:

M2 x 10mm
M2 x 12mm
M2.5 x 10mm
M2.5 x 12mm

Will probably post tomorrow AM

 :ThumbsUp:

Dave


« Last Edit: July 13, 2019, 08:34:29 AM by Bluechip »

Offline Jo

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Re: 15cc Seal and 30cc Seal Major
« Reply #119 on: July 12, 2019, 01:32:38 PM »
 :-*
Enjoyment is more important than achievement.

 

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