The Shop > Tools
Harrison L5 rescue
micktoon:
Hi Oz , I will do, I think I am probably going to have to make some of mine or sleeve shafts as both the bush and the shafts are worn in some places so just a new bush would not really fix the problem but I will keep you posted.
G&M tools have some L5 parts on Ebay there are some Norton box parts but not bushes listed, I contacted them about some badges and they said all they had was listed on Ebay , I dont know if they meant all L5 parts or just the badges mind.
Cheers Mick.
Manxmodder:
I was looking at my screw chart plates earlier and also the photos of yours.
They do differ a bit but a possible solution, if you have to restore what you have, would be to apply nitromors and strip out the old paint from the undercut reliefs then refresh the raised chart plate lettering and surfaces on super fine abrasive paper,with the paper set on a flat plate with thin a smear of grease applied to the back to prevent it slipping around and to keep it perfectly flat whilst your lapping the chart faces.
When the raised parts are looking good then then spray a couple of thin coats of cellulose paint on the front faces and oven dry the paint till its nice and hard.
Finish of by going back to the abrasive paper on the flat plate until you've removed enough paint from the high spots to fully reveal the numerals and lettering,then thoroughly clean and apply a coat of clear laquer. (I've used this technique in the past to restore similar type charts and badges.)
I guess you've already considered doing something like I describe but I must emphasise the importance of keeping the abrasive paper absolutely flat on the surface plate,hence the use of grease on the backside.
I hope some of these suggestions are of help to you but either way I'll be interested to see how you resolve the problem.
Are any of your charts chrome plated,or are they all of unplated the brass type?....OZ.
micktoon:
Hi Oz,if the plates were better nick what you have mentioned was going to be my plan but these are a bit battered to start with and now look worse due to them little riverts being a nightmare to bet out, I thinkI will put an ad on hoeworkshop, someone may have soe tucked away somewhere and plan B might be to some how try to replicate something similar ? I still have not really thought of how yet.
At least one had been chrome or nickle plated but it was half rubbed off down to brass, either way I would be happy with brass finish
Cheers Mick
awemawson:
Mick, you could photographically etch them yourself using the same technique used for making pcbs. Get a good dense black and white photograph, print on a laser printer at the right scale to size it properly onto 'overhead projection film', spray the brass with photo resist (ebay abounds) expose to uv (sun ray lamp) through the film, wash away the exposed bits with weak potassium hydroxide solution, etch the result with ferric chloride.
Another slightly simpler way is to print onto paper, lay the paper on the brass and iron it on. The ink in laser printers is basically carbon bonded by plastic. The heat fuses the plastic and bonds it onto the brass. The plastic acts as the etch resist. Takes a bit of experimentation but it does work. You can buy special papers to make the process easier.
Manxmodder:
Ah well,if they're a bit to knackered then Andrew is pointing you in the right direction with the photo resist or carbon paper resist and Ferric etch methods he describes(good man Andrew for pitching in there :thumbup:).
I have also used a slightly different technique to produce ferric etched clock faces for a custom show bike many years back.
What was done on that occasion was a silk screen negative was made from the the artwork master and the ink was squeegeed through the screen onto the brass blanks,and when dry they were dropped into the Ferric Chloride until satisfactorily etched then ink cleaned of with solvent.
Back then we used leteraset rub on letter and numeral transfers to create the art master,but these days I think the inkjet printer is the weapon of choice.
You could also consider asking if any members on the Harrison Lathe forum have any new/old stock L5 screw charts for sale.....OZ. Link to Harrison Lathe Forum:
https://groups.yahoo.com/neo/groups/harrisonlathe/info
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version