Non-standard size steel washers

[Ian Law]

I need 48 non-standard size steel washers to complete my wing spar fittings: they have to be brazed in place before reaming holes to size.

To save a lot of time I planned to have these laser or water jet cut. The last quote for laser cutting was for £90 + VAT, so it looks as though I shall be flogging away again with hacksaw & file, unless anyone can suggest an easy way of doing this job or recommend a laser cutting operation that would be willing to undertake this small job for me.

Any suggestions would be appreciated.

(Apologies if this post appears twice - my first attempt appears to have vanished after I clicked "Submit".)

Ian

[ian herdis]

What size ID / OD do you need.

Ian

[Ian Law]

Ian,

Ideally I need the following, preferably from 4130N steel or an equivalent that is at least as beefy:

# OD ID Thickness
16 3/4" 6mm 0.063"
16 5/8" 6mm 0.063"
8 1/2" 6mm 0.050"
8 1/2" 4.5mm 0.050"

Tolerance/thickness isn't really critical; as already described, they will be brazed in place on the fittings and just need enough spare metal to allow the finished holes to be reamed to size.

I made up some myself (hacksaw/file/finished off on mandrel in lathe/electric drill etc) for the fittings in the fuselage, but want to avoid this unpleasant and time consuming job if there is an affordable alternative.

I don't seem to be having much luck finding any suppliers on the web and minimum quantities are always a problem.

Ian

[ian herdis]

You could avoid the hacksaw part by using a holesaw

Most holesaws use a 1/4 inch pilot so remove pilot and use a guide plate to locate the holesaw, just drill a hole in a bit scrap with the holesaw you are going to use then clamp this to your good material.

Use say a 1 inch to produce 3/4 inch blanks ready to tidy up.

Ian

[Ian Law]

Ian,

By coincidence, earlier today, I looked at some of the Starrett holesaws I have and realised I could easily remove the 1/4" drill piece in the arbor and replace it with a stepped shaft that I should be able to machine in my elderly lathe, with care. I'd need 2 new rods - 1/4"dia. at the top and 6mm and 4.5mm at the business ends. Should be a quick and easy job ( not necessarily in my wheezy old lathe, tho' ).
By another happy coincidence, the 3 saws that I have should produce the 3/4, 5/8 & 1/2" dia. "washers" ,so I will have a go in the next few days and see how well this works, using my drill press of course.

Many thanks for your help.

Ian

[ian herdis]

No problem, its good to use those little discs we usually sweep up and toss in the bin

Ian