Honda CB750 Sandcast

Restoration of 5369

UK Pete · 54 · 58845

UK Pete

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Thanks for the comments, yes i have loads of motivation at the moment, and i spent a huge amount of man hours just to get the cases like that ready for spraying, now speaking of spraying as i type the cases are still wet after spraying, my god they have come up nice, i am really proud of my work here, take a look now they are all sprayed up, i will oven cure them later

All trussed up ready for spraying



All sprayed up






lots of rough casting snots



The paint was almost perfect match for the original engine finish i found in the starter cover






ashimotok0

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Nice job Pete .. you are obviously steaming ahead.
Which paint did you use?
Hope that was not the missus's oven you used ! ;D

Cheers .. AshD


UK Pete

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Masking tape off, just pop it in the oven for 1.5 hr at 220c
The wife has gone out for a couple of hours when she comes back she will go ballistic, oh well shit happens







UK Pete

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Nice job Pete .. you are obviously steaming ahead.
Which paint did you use?
Hope that was not the missus's oven you used ! ;D

Cheers .. AshD

Ash yes it was her oven, and the paint used is simoniz engine enamel heat resistant to 800 and petrol resistant i think, best paint i have come across for our engines
pete


UK Pete

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I had a few hours spare today so i got the frame out for inspection, well i have to say the frame is very solid, it is hard to believe that its 45 years old, frames dont stay in that conditition here in the UK









Anyway the only repair needed to the frame is the side stand bracket, it seems quite common for these brackets to get ripped off, usually by kickstarting the bike while standing on the footpegs with it on side stand




Out with the chisel and angle grinder and off with the remains of the old bracket



My new side stand bracket arrived , i have to say fair play to will from classic bike imports  (the guy i bought this bike from) he kindly sent me a piece of frame with the bracket on , so i ground off the welds and got the bracket off and cleaned it up  ready to weld on




« Last Edit: September 16, 2014, 11:56:58 am by UK Pete »


UK Pete

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Thought i would do a bit of work on my rear wheel, looks to be an original untouched sandcast wheel, however i dont see a perfectly rounded rim, it certainly is more rounded than k1 onwards, anyway i dissasembled the spokes and have chemically stripped the rust and zinc from them and they are not bad condition  , has  anyone bothered to restore their original spokes and nipples , i am certainly thinking of re plating mine , i might give it a go and see how they turn out












UK Pete

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Some of my spokes, acid stripped them lightly buffed with scotchbrite

Has anyone restored spokes before?? or do people not bother




Steve Swan

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i have my originals bright zinc plated.  if you go that route, be certain the plater 'bakes' them after plating, the plating 'hardens' them.  baking relieves the stress.


UK Pete

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Yes Steve i have considered that Hydrogen embrittlement may be a factor, i would be doing the plating myself, and same as previous items with a high tensile strength, i have had to oven bake them for hour and a half +, i suppose spokes would be the same
i might just do the nipples and gold/yellow passivate them as that is the hardest part to find now, the repop spokes are cheap and easy to get hold of, but they all have bright zink nipples which do not look the same as the original Daido's
I was just putting it out there to see if the die hard restorers go down this route or not



UK Pete

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Each day i come home from work or have some spare time i try to do a bit of work on some of my retoration bikes, at the moment my sancast is obsessing me so that gets all the attention, so more pictures of what i have been up to this week

The rear wheel is getting a bit of time for now, i cleaned up the rear hub and satin polished it, the hub looks great but i am  disappointed that there are so many casting flaws, it was definitely not corrosion or the cleaning process and looking at it magnified x30 you can clearly see it as a casting flaw, any one elses hub got these horrible pits, they are way to deep to sand or polish out, having said that you have to go up close to see them they dont really come out in pictures and i might be a bit fussy as looking at the pictures it looks nice





UK Pete

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Started to blast my frame yesterday, i made up a blast booth and got stuck in, it is quite slow going so i have not finished it yet but hear are some pictures of me in action


[imghttp://cb750sandcastonly.com/coppermine/albums/userpics/10004/sandcast_006~2.JPG]http://[/img]



UK Pete

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As you can see from my previous post i am tackling the blasting and painting of my frame myself,this is for two reasons, number 1 is i just dont trust anyone to do it with the same care and attention that i will, and reason 2 is i usually powdercoat but this de values the sandcast , it is a big no no when you speak to any sandcast owner restorer, oh yes there is a third reason , i do not have the money to pay someone else
Yesterday i thought this would be a doddle probably an hour or two's work, how wrong could i be, my blaster just was not getting through the two layers of paint very quickly if atal in places, so i whipped out and got some paint stripper, quick word of advise do not ever by nitromores stripper, its expensive and totally shit, it just would not lift the paint, so i was out side till 11 last night trying to scrape off soft paint with a stanley blade and then go over it with a scotchbrite wheel on the drill, this got a good deal of it off so this morning i did more scraping , more blasting and more scotchwheeling and ended up with a shiney bare metal frame, all i can say is thank goodness that is over
now i have the problem of finding a doner frame and getting the seat hinges cut off and welded on to my frame as some mother f--er ground them off, as well as the side stand bracket which i have just done
now with all this moisture in the air at this time of year it would be stupid to leave it bare metal, so i have sprayed it up with some rust preventing primer till i get the seat bracket  situation sorted, that way it wont start rusting in a hurry, i also wrapped it in a blanket then boxed it up and have stashed it
Take a look there is absolutely no rust on this frame, the very light surface rust that was there came clean off with the blaster, so them two layers of awkward paint done the job, other than the ground off brackets you could not wish for a better 45 year old frame
pete




[imghttp://cb750sandcastonly.com/coppermine/albums/userpics/10004/sandcast_008~2.JPG]http://[/img]



UK Pete

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I stripped the front hub from the sandcast and my k0 today and i cant believe the quality of the original chrome bits from the hubs take a look they are  amazing for original 1969 parts, no need for re-chroming