Hi,
I adopted restoring vintage valve radios as a winter hobby when I retired in 2000 knowing nothing about them; I wanted to leave my comfort zone and try something new. I then spent the next ten years becoming deeply involved in this new hobby to the point of having articles published in the BVWS Bulletin (British vintage wireless society). I was self taught with help from radio forum members but I also learned transformer winding; wood veneering and French polishing.
In 2009 I was honoured by the society gaining top award for best restoration 2009 which I found truly humbling considering I had started the hobby from scratch just to enjoy during winters. The restoration wasn't a vintage radio but an AVO Wave Winder these winders used to wind tuning coils and they are rather complicated machines. Whilst buying enameled copper winding wire I spotted this very rough looking winder and as I'm a mechanical engineer thought what a lovely project it would make; even in its rough state it wasn't cheap but I soon had it on the bench. The winder proved to be virtually scrap it was seized solid with rust and parts were missing; just like the kind of challenge I like.
It's a long story but I fully rebuilt the winder and made the parts which were missing; the only problem was it didn't have a single gear and the manual stated it should have about 45 change gears in the full set? What a dilemma; I'd never made a gear and didn't even know the diameters or number of teeth also what was the tooth profile? I'm a member of a vintage wireless forum in fact the first ever forum I joined; the restoration was being watched and I posted on the forum for gear information. a forum member stepped up kindly sending me pictures of his own working winder so at least I now had a basic idea.
At the time I'd bought a very old rare Myford engineering lathe which was described as in excellent condition; having collected the lathe and it now on my bench running it didn't take long to find the headstock main bearing housing was broken rendering the lathe scrap; oh what fun I do have. I clamped the bearing housing securely and proceeded to experiment cutting gears firstly from Whale Tufnol. The biggest problem was the gear diameters and the tooth profile; I did many hours researching and "Involute" gears looked the correct type but how to make these? I've been using lathes for over half a century but never for a job like this; I didn't even have a vertical slide or dividing head so I was really up against it.
I'm as stubborn as they come and I was going to get this winder working however long it took so lots more researching; I found out how to make a single point cutter of the correct Involute tooth profile but typical of my luck just one cutter wouldn't cut all the gears I needed a set of four correctly profiled cutters so I made four. Now I needed to mount the cutter and did so using a heavy length of BMS (round bar stock) between centers with the cutter mounted on center. Now I needed a way of engaging the cutter so I made my own vertical slide from offcuts of metal I had to hand; yes I'm tight. No dividing head so what could I do to index the blanks; I'm useless with CAD and tried lots of CAD programs finding it difficult to draw a straight line; the lines were zig-zags; then I found;
FREE CAD Software | Design Custom Parts | eMachineShop
WOW I was amazed to find emachineshop showed a "Spur gear wizard" I couldn't even draw a straight line but this got my full undivided attention; after lots of playing around sussing out how to use the wizard I finally printed of a gear drawing but it was 8" diameter? What now and how do I sort this out; simple once the answer is known; print to actual size not print to fit page; further to this I found I could adjust printed line width so now I had my first gear paper template; this is what I had dreamt up; I intended to uses double sided self adhesive tape to attach each paper template directly to the face of the prepared gear blank; I took a great deal of care to get this perfect. I turned a mounting boss securing the gear blank to the vertical slide and set about cutting my very first gear; I was very apprehensive indeed never having seen this done and knowing the lathe was rubbish.
I successfully completed the first gear the indexing being directly between the cutter tip and aligned with the template; it's surprising just how accurate this proved to be and certainly accurate enough for my needs. I then wanted to go further and make a set of cast iron gears; I visited Blackgates Model Engineering and had poor Duncan cut 45 Meehanite cast iron blanks; at the time I think the blanks cost £80 plus £10 because of the time spent in cutting which was very reasonable; I had the blanks cut slightly thick allowing facing in the lathe.
I took a big gamble with the first cast iron blank; I had faced it both sides and brought it to correct diameter; I set the cutter to give full depth then dropped the vertical slide down; with the lathe in motion I did as previously and very slowly wound the blank up into the cutter; I was absolutely amazed to see the slot appear as if by magic; it's the slot each side of the tooth which is cut; now I really got stuck in and could cut a slot in less than a minute each; the problem now was I was so fast at starting and stopping the lathe the motor expired in a cloud of smoke; no problem I replaced the motor and cracked on. Single phase motors with capacitors don't like frequent start/stop cycling.
With 45 gears now successfully cut I needed something to keep them together or these too would become separated and lost just as the original gears were; I designed and made a bespoke comb jointed wooden box and even dreamt up my own method of making a brass nameplate.
I'm not the sharpest tool in the kit and I'm not smart or expert in anything; I made many frustrating mistakes along the way but I gained knowledge through each mistake; I've never seen gear indexing done previously using a paper template the way I did so I'm pretty sure it's unique to me as is my method of making the brass nameplates. I'm just downright stubborn and too stupid to quit and walk away when things go wrong; I've never failed yet in any project or job I've attempted and feel the only way to really fail in anything is not to try. I hope my ramblings are of interest.
Kind regards, Colin.
The AVO wave winder as bought. It was expensive scrap but how I like to be challenged and this proved to be a long challenge indeed.
The winder was seized solid with rust; here I've applied oil and managed to remove components.
The main shaft simply didn't want to budge; I tried heating but in the end resorted to making the clamping lever from offcuts of steel; I needed to exercise great care because to break the casting would be a disaster; with more heat and this time pressure applied I finally removed the shaft much to my relief.
emachineshop spur gear wizard was used here seen a number of paper gear templates together with hole punch I turned to ensure alignment on the vertical slide.
Here a pair of gears being cut; I took advantage of this when two of the same size were needed in the gear set.
Here is the cutter tip being indexed against the paper template; it was so amazingly simple and worked a treat; the bottom set screw locked the mounting boss and the top set screw allowed rapid indexing it was a very solid mounting.
Not having an expensive vertical slide wasn't going to stop me; I made this from odds and ends I had to hand; it proved very accurate once set up and adjusted; the lathe carriage was securely locked so all I needed to do was to determine depth of cut on the first slot then it was just a case of indexing and lowing the slide to clear the cutter; with the lathe in motion raising the slide engaged the cutter and in less than a minute a full depth slot was cut; the 60T gear took less than an hour.
After many hours researching and testing my dreamed up ideas here are the gears at home in their bespoke wooden box.
Having gone to so my effort it was only right that I should fully complete the job to the best of my ability so I decided to experiment with yet another new idea in making this brass nameplate; all the letters etc. were cut out using a fretsaw with piercing blade fitted; fiddly and time consuming but I'd come this far so what's a bit more time. Super glue was used and then it was all sprayed black from a rattle can; a full sheet of wet or dry abrasive 240G was placed on a planer cast iron table and the plate rubbed upon the abrasive paper with the result shown; to complete it a coat of clear lacquer was blown on from a rattle can.
I hope all this makes sense because it takes a lot of time putting a thread like this together; it covers the main parts but when I did this project it was very involved indeed as I tested my ideas out; as I say I like to leave my comfort zone and try something new; I must be barking mad but I'm never bored.
I adopted restoring vintage valve radios as a winter hobby when I retired in 2000 knowing nothing about them; I wanted to leave my comfort zone and try something new. I then spent the next ten years becoming deeply involved in this new hobby to the point of having articles published in the BVWS Bulletin (British vintage wireless society). I was self taught with help from radio forum members but I also learned transformer winding; wood veneering and French polishing.
In 2009 I was honoured by the society gaining top award for best restoration 2009 which I found truly humbling considering I had started the hobby from scratch just to enjoy during winters. The restoration wasn't a vintage radio but an AVO Wave Winder these winders used to wind tuning coils and they are rather complicated machines. Whilst buying enameled copper winding wire I spotted this very rough looking winder and as I'm a mechanical engineer thought what a lovely project it would make; even in its rough state it wasn't cheap but I soon had it on the bench. The winder proved to be virtually scrap it was seized solid with rust and parts were missing; just like the kind of challenge I like.
It's a long story but I fully rebuilt the winder and made the parts which were missing; the only problem was it didn't have a single gear and the manual stated it should have about 45 change gears in the full set? What a dilemma; I'd never made a gear and didn't even know the diameters or number of teeth also what was the tooth profile? I'm a member of a vintage wireless forum in fact the first ever forum I joined; the restoration was being watched and I posted on the forum for gear information. a forum member stepped up kindly sending me pictures of his own working winder so at least I now had a basic idea.
At the time I'd bought a very old rare Myford engineering lathe which was described as in excellent condition; having collected the lathe and it now on my bench running it didn't take long to find the headstock main bearing housing was broken rendering the lathe scrap; oh what fun I do have. I clamped the bearing housing securely and proceeded to experiment cutting gears firstly from Whale Tufnol. The biggest problem was the gear diameters and the tooth profile; I did many hours researching and "Involute" gears looked the correct type but how to make these? I've been using lathes for over half a century but never for a job like this; I didn't even have a vertical slide or dividing head so I was really up against it.
I'm as stubborn as they come and I was going to get this winder working however long it took so lots more researching; I found out how to make a single point cutter of the correct Involute tooth profile but typical of my luck just one cutter wouldn't cut all the gears I needed a set of four correctly profiled cutters so I made four. Now I needed to mount the cutter and did so using a heavy length of BMS (round bar stock) between centers with the cutter mounted on center. Now I needed a way of engaging the cutter so I made my own vertical slide from offcuts of metal I had to hand; yes I'm tight. No dividing head so what could I do to index the blanks; I'm useless with CAD and tried lots of CAD programs finding it difficult to draw a straight line; the lines were zig-zags; then I found;
FREE CAD Software | Design Custom Parts | eMachineShop
WOW I was amazed to find emachineshop showed a "Spur gear wizard" I couldn't even draw a straight line but this got my full undivided attention; after lots of playing around sussing out how to use the wizard I finally printed of a gear drawing but it was 8" diameter? What now and how do I sort this out; simple once the answer is known; print to actual size not print to fit page; further to this I found I could adjust printed line width so now I had my first gear paper template; this is what I had dreamt up; I intended to uses double sided self adhesive tape to attach each paper template directly to the face of the prepared gear blank; I took a great deal of care to get this perfect. I turned a mounting boss securing the gear blank to the vertical slide and set about cutting my very first gear; I was very apprehensive indeed never having seen this done and knowing the lathe was rubbish.
I successfully completed the first gear the indexing being directly between the cutter tip and aligned with the template; it's surprising just how accurate this proved to be and certainly accurate enough for my needs. I then wanted to go further and make a set of cast iron gears; I visited Blackgates Model Engineering and had poor Duncan cut 45 Meehanite cast iron blanks; at the time I think the blanks cost £80 plus £10 because of the time spent in cutting which was very reasonable; I had the blanks cut slightly thick allowing facing in the lathe.
I took a big gamble with the first cast iron blank; I had faced it both sides and brought it to correct diameter; I set the cutter to give full depth then dropped the vertical slide down; with the lathe in motion I did as previously and very slowly wound the blank up into the cutter; I was absolutely amazed to see the slot appear as if by magic; it's the slot each side of the tooth which is cut; now I really got stuck in and could cut a slot in less than a minute each; the problem now was I was so fast at starting and stopping the lathe the motor expired in a cloud of smoke; no problem I replaced the motor and cracked on. Single phase motors with capacitors don't like frequent start/stop cycling.
With 45 gears now successfully cut I needed something to keep them together or these too would become separated and lost just as the original gears were; I designed and made a bespoke comb jointed wooden box and even dreamt up my own method of making a brass nameplate.
I'm not the sharpest tool in the kit and I'm not smart or expert in anything; I made many frustrating mistakes along the way but I gained knowledge through each mistake; I've never seen gear indexing done previously using a paper template the way I did so I'm pretty sure it's unique to me as is my method of making the brass nameplates. I'm just downright stubborn and too stupid to quit and walk away when things go wrong; I've never failed yet in any project or job I've attempted and feel the only way to really fail in anything is not to try. I hope my ramblings are of interest.
Kind regards, Colin.
The AVO wave winder as bought. It was expensive scrap but how I like to be challenged and this proved to be a long challenge indeed.
The winder was seized solid with rust; here I've applied oil and managed to remove components.
The main shaft simply didn't want to budge; I tried heating but in the end resorted to making the clamping lever from offcuts of steel; I needed to exercise great care because to break the casting would be a disaster; with more heat and this time pressure applied I finally removed the shaft much to my relief.
emachineshop spur gear wizard was used here seen a number of paper gear templates together with hole punch I turned to ensure alignment on the vertical slide.
Here a pair of gears being cut; I took advantage of this when two of the same size were needed in the gear set.
Here is the cutter tip being indexed against the paper template; it was so amazingly simple and worked a treat; the bottom set screw locked the mounting boss and the top set screw allowed rapid indexing it was a very solid mounting.
Not having an expensive vertical slide wasn't going to stop me; I made this from odds and ends I had to hand; it proved very accurate once set up and adjusted; the lathe carriage was securely locked so all I needed to do was to determine depth of cut on the first slot then it was just a case of indexing and lowing the slide to clear the cutter; with the lathe in motion raising the slide engaged the cutter and in less than a minute a full depth slot was cut; the 60T gear took less than an hour.
After many hours researching and testing my dreamed up ideas here are the gears at home in their bespoke wooden box.
Having gone to so my effort it was only right that I should fully complete the job to the best of my ability so I decided to experiment with yet another new idea in making this brass nameplate; all the letters etc. were cut out using a fretsaw with piercing blade fitted; fiddly and time consuming but I'd come this far so what's a bit more time. Super glue was used and then it was all sprayed black from a rattle can; a full sheet of wet or dry abrasive 240G was placed on a planer cast iron table and the plate rubbed upon the abrasive paper with the result shown; to complete it a coat of clear lacquer was blown on from a rattle can.
I hope all this makes sense because it takes a lot of time putting a thread like this together; it covers the main parts but when I did this project it was very involved indeed as I tested my ideas out; as I say I like to leave my comfort zone and try something new; I must be barking mad but I'm never bored.
