1961 CB72 Project

[G-Man]

Alan

I do degrease and wire-wheel the parts but I let the platers do all of the chemical stuff.

If things are really crusty I might dip them in Oxalic acid (wood bleach).....

G

Graham, they looking great,do you acid clean your parts first before you send them, or do they do the lot.

[jensey]

Hi,

I'm cleaning my parts with acid before bringing them to the platers.
This way I can eventually work on small irregularities and smooth up things if necessary.

Irregularities which are hard to see when the surface is rough / corroded

Jensen

[G-Man]

Jensen

Always good to have your input. Sometimes the parts may need mechanical cleaning or dipping to see damage. But if the parts are simple and in good condition they have a quick clean on a rotary wire brush and go in the box for plating.

I use a variety of methods depending on the part(s) but generally most part go straight in after cleaning. With screws I like to hammer the burrs back in to place then give the heads a polish in the lathe. It's surprising how old chewed-up screws can be made to look like new with very little effort.

G

for

Hi,

I'm cleaning my parts with acid before bringing them to the platers.
This way I can eventually work on small irregularities and smooth up things if necessary.

Irregularities which are hard to see when the surface is rough / corroded

Jensen

[sarals]

Graham, any thought to doing a small "manufacturing run" of those kickstart gears? I know that there must be several (!) people out there with splines on their kickstart shafts that have seen better days. :)

[G-Man]

Sara

It's a possibility, but I would like to put one to the test to see that it will last. A side effect of the larget diameter of the CB250 shaft is that any slack in the bearing bush can be taken out by careful matching of the bush to the shaft.

Of course, as soon as I'd finished these three, a NOS one turned up on eBay. :-)

G

Graham, any thought to doing a small "manufacturing run" of those kickstart gears? I know that there must be several (!) people out there with splines on their kickstart shafts that have seen better days. :)

[jensey]

I use a variety of methods depending on the part(s) but generally most part go straight in after cleaning. With screws I like to hammer the burrs back in to place then give the heads a polish in the lathe. It's surprising how old chewed-up screws can be made to look like new with very little effort.

Yes, I use a (fine) file to follow the curves of the head, after that I polish (grain) it with grade 800.
If the thread looks a little damaged or corroded, I cut the thread with a thread cutter.

Damaged "hard to get" nut's are candidates for the milling machine (a one day session once a year because I don't have one my self at home). Big corroded bolts and heavy corroded important bolts and nuts are wet blasted before the sink process.

Having dismantled over 30 engines last year (CB450's and CB72's) I have a box of 25 kilo's of fasteners hardware alone, all ready to get the same treatment, but that's work for the long (next) winter evenings. It's a lot of work, checking bolt by bolt, nut by nut.

The preparations are the most important step in the sink process.

[G-Man]

Starting a long flight back home today so I am looking forward to a little workshop time.

I've got all of the shiny zinc parts to finish off the cam chain tensioner for this project and several others.





It'll be nice to see how many complete assemblies I've got and how many spares there will be. There are quite a few 'needy' projects in the collection.....

Once I have the tensioner and the primary side cover finished I can get on and finish the engine. The frame is ready but I shall have to build up the wheels before it starts looking like a bike again.


G