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cropwell
30-03-2016, 05:42 PM
It is my harmonica teachers 70th birthday in April and I thought I would have a go at a harmonica case to fit a Seydel Saxony harmonica.
The oak cost me £7.50 for an 8ft length of 3" x 1".

The first try ended up showing me that my MD machine was not cutting square, so I spent a day with a large engineers square (the large engineer wants it back !) and a dial gauge to find out where the skew was. I found it and corrected it, but it is a design weakness, so I have to be wary that it could skew again !!!!

I used most of the oak to make firewood, and when I got the first good cuts I changed the design. So none left really.

After skimming the top, cutting the cavity and outside profile for both the bottom and the top, I cut a jig in softwood and put the pieces in it with some double sided tape and skimmed the faces with my new Chinese bottom cleaner (£2.08) before cutting the recess for the brass plate.


I attacked it with sandpaper and gave it a coat of sanding sealer before bringing it up to a finish with wire wool and wax. There was a slight disaster when one of the hinge screws broke and I had to drill it out, but it taught me to lubricate the screws to make them go in more easily (ooh err missus !). Inside I lined it with strips of adhesive foam and a top layer of black self adhesive felt. I CNC cut a perspex template and used a scalpel with a new blade to cut them out. My experiments with a drag knife were a failure !


The brass plate was engraved with code generated with Vcarve, but the woodwork was drawn with AutoCAD and converted toGcode with EstlCAM V8.


There were a few fails and bodges, but otherwise I am pleased with the end result.

18053180541805518056180571805818059180601806118062

Clive S
30-03-2016, 05:55 PM
Very nice Rob. It's a credit to you.:applouse: I take it you have used brass screws in the oak as steel one's can make the oak go black

lucan07
30-03-2016, 06:41 PM
Looks good he should be well happy, shame he won't be able to play for a while, 70 candles gonna leave him short on blow!

Clive S
30-03-2016, 06:49 PM
Looks good he should be well happy, shame he won't be able to play for a while, 70 candles gonna leave him short on blow!I'm practising that manoeuvre but I have a plan with an airline up my sleeve.:stupid:

cropwell
30-03-2016, 07:08 PM
Very nice Rob. It's a credit to you.:applouse: I take it you have used brass screws in the oak as steel one's can make the oak go black

I agonised about that for hours, then decided "sod it" (or words to that effect). The only screws I could get were steel with an antique brass finish, so I put them in a charred screw socket with plenty of wax in the socket.

Actually Clive I am surprised you didn't spot the big mistake. I'll PM you what it is :culpability:

Washout
01-04-2016, 01:16 PM
Really nice and now intrigued on the "big mistake" - the hinges not flush fit perhaps?

lucan07
01-04-2016, 02:36 PM
intrigued on the "big mistake"

I reckon his name is JOE

cropwell
01-04-2016, 03:15 PM
Really nice and now intrigued on the "big mistake" - the hinges not flush fit perhaps?

If you look carefully, you will notice that the grain pattern is different on each side of the case. If I had cut with either blank turned round 180deg, the grain patterns would have matched. Nevertheless, I am sure Toby will be happy with the case.

Rob