Can anyone give me a suggestion on how to create the angled carb hole in the dash where the adjusting rod goes through? The original dash I have has two angled holes, one on the drivers side that was covered by the brass plate, the other is on the right side where it ought to be. The angle is on the inside of the dash as well as in the engine compartment. Is there a special tool that makes that cut?
I used a 12" long drill bit. A scrap piece of wood can be cut at the proper angle to use as a guide so that you hold the drill at the proper angle.
The holes are supposed to be on both sides of the dash for many years of Model T, so your old one was correct. That way the dashboard could be reversed if it was used on a British RHD Model T.
Royce, does that mean I could use a 1913 dash and simply reverse it for my RHD?
That is correct.
Royce, why can't I just use the old, original dash to make the adjusting hole? Do you know what the angle is if the old dash won't do?
The hole is 1/2" diameter and drilled at an angle of 20 degrees to the dash for a standard dash and at a larger angle for the 1911 Torpedo/Open Runabout.
The easiest way to make a jig is to take a substantial block of wood and clamp it vertical in your drill press and then drill the hole down through the block as you might drill a hole through a lamp. Then use your miter on your table saw to cut the block of wood at the correct angel to the table saw blade and thus make a block that holds the drill bit at the correct angle. You will need to figure out the exit hole location and clamp a large piece of wood there to prevent tear out of the plywood veneer at the hole exit and entrance holes. I put wide masking tape down against the dash veneer to hold it and then put the wood blocks on top of the tape. That makes a clean and perfect elliptical shaped hole on both sides of the dash. It is tricky but with practice you can do it perfectly. I made my guide block out of steel and I use a very long bit. The exit hole must be into a sacrificial wood block.
Thanks for the clear explanation, John - really helpful!
It is a good idea to clamp a second block of wood on the other side of the dash so that as the drill bit emerges from the wood it makes a clean cut with out tearing out the grain.
sorry! I just read all of John's post. Do as he recommends and you should not have a problem.
John, how big a piece of wood would you suggest? 4x4?
I don't suppose anyone makes a brad point bit that long? They do a much nicer cut in wood than a regular twist drill.
Normally I would agree with the brad point bit but they are designed to cut a perfect circle when the bit enters at a 90 degree perfect right angle to the cutting surface. The angled drill of the dash hole will result in the bit grabbing the veneer and tearing out a big hole. It is kinda like trying to use a fly cutter on a mill with a single cutting bit and then trying to cut at an angle. You get a very rough interrupted cut chewing of the surface on the way in and out. I use a 3 flute bit with a more or less standard 135 or 115 degree tip. I have used both with about the same results. Starting the drill into the dash is the hardest part since the moment the drill bit touches the surface it tries to "walk" across the surface and you need to have the bit spinning as fast as possible and with a firm grip on the drill to fight its tendency to self feed at the moment of contact. Best to practice on some scraps in a vice first to know what to expect. I have drilled many dashes but it isn't the fun part of doing a dash since if something slips I get to start all over with the dash.