Tap Plungers

[simon.holyfield]

Chaps,

I know some of you have made your own petrol tap plungers. What have you used to cut the slots for the retaining screws? Slot drill?

[paul.jameson]

I use the appropriate size milling cutter which is how I think they were done originally.

[pkrichardson]

yes slot drill is what you want slot drills have 2 flutes for plunge cutting as blind slots milling cutters 4 flutes for open ended slots
Pete

[simon.holyfield]

I'm planning on making some plungers with o rings. I'm going to try and smooth the port edges in the tap body with a Dremel to avoid tearing the rings as they pass the port.

Anyone used that approach?

[paul.jameson]

That sounds a bit like a Rolls-Royce for a Ford job. If you make adjustable plungers - you adjust them (but I admit you need to replace the corks every 5 years or so.) What was the life expectancy of an Ariel in 1937 ? - maybe 10 years at best - and the intervention of a World War to hasten disrepair.

[simon.holyfield]

It is a bit. The reserve tap on the W/NG is dripping and not responding to adjustment - I have a couple more taps to refurbish for the Mk1 and the FH, and given that I need to do some plunger work, that I have some brass round bar, a box of o rings and a lathe...

Well, you know how simple jobs grow.

[stuart.wilby]

I have some photos for you showing o rings on tap plungers but !!! How the hell I get them onto this is a mystery. It needs to be made simpler my brain is dying, I’ll try to pm.

[stuart.wilby]

Slot drill has one side of the cutter longer than the other, it is designed to go past the centre line of the hole to ensure removal of the material, the end mill has to come in from the side because the cutters have a recess in the middle to allow the chips to get out of the cutter path and allow for sharpening.

[simon.holyfield]

Thanks for the pictures Stuart. I'll post them when I get on a PC.

Do you have any problems with the ports tearing the o rings up?

[stuart.wilby]

The pictures were taken from the net as a basis for the project, when I did the conversion I made the brass replacement longer where it comes through the chrome tap push pull thingy, enough to pein over the end ( as before) the tap which I converted is in a BSA Golden Flash tank and is still going strong after 2 years, just make sure the burrs are removed. There may be a bit of accurate measuring and perhaps some trial and error required,Figured out the attachment upload.