Thread: Rhumba box tapping

I would be pleased to do it for you if you don't feel confident. Problem with that offer is that I am flying up to the Kimberlies for a few weeks, and won't be around until late next month.
I could probably still do the job and send it to you from Kunanurra. I am staying with my brother who owns a large engineering business, so access to gear for the job is not a problem.
PM me if you want it done.

I am sure you will get plenty of tapping advice here though.

That is very generous Fossil but it would be better if you stayed here and I went to the Kimbeerlies.
I could do with a bit of barra fishing.

Confidence isn't my problem yet!

I have read a number of threads but just not sure how to apply the 'knowledge'.

Is it practical for me to tap 3mm holes? It would be a pain if I was continually snapping the tap. I would like to give it a try myself and if it is easy enough then I can adjust the spacing of the holes to suit the different tyne widths.

I'll send a pm, just in case.

3mm tapped holes in mild steel is fairly easy to do. Are the holes all the way through or do you want a thread tapped in to a blind hole? Tapping in to a blind hole is more complex, but completely doable.
I don't have time at the moment to give a tutorial, as i have a bit to get cleared away at work before I go fishing. I'll try to get something down before i go. My brothers friend is taking us away in his chopper to a really good spot for two days. That is the part of the trip that i am looking forward to most. There wil only be the three of us, so I am told that leaves the equivalent of two body weights in beer, that we can take on board. I hope we don't run dry.

What a tough trip.

The holes can go right through.

The local shop had nothing smaller than 6mm so I will have to search around. I bought a T piece to hold the taps 3mm plus.

My trips have been to East Aligator and up along the coast from Darwin. It is a great way to do a lot of casting and catch some great fish. It sounds like you have the right transport to find a good spot.

Scally

Tapping through holes in mild steel is pretty easy to do - it must be, I can do it and I haven't even broken a tap!

Like most things, you can only go so far reading, you have to go ahead and do it for yourself. As always, it is best to practice on some scrap first.

My tips:
1. quality taps - Sutton or P&N etc. You can use the cheaper ones, but they are more fragile
2. the right tap - make sure that you use a taper tap or an intermediate tap and not a plug tap (Plug taps are to cut the last bit of the thread at the bottom of a blind hole), taper and inter taps have a taper that makes starting the cutting possible.
3. the right hole size - look at these charts
4. a vertical hole - self-explanatory
5. the work held firmly in the vice horizontally
6. the tap introduced gently and vertically (that's why the work is horizontal) - I check the arms of the tap wrench with the courses of the brickwork in my workshop
7. enough lubricant - I use TapMagic and a drop or two is enough for little holes like 3mm. Some people use WD40 and say it works fine
8. gentle but firm pressure to turn 1/4 turn and back off 1/8 turn to release the swarf

It works for me, it should for you.

And I was going so well too.

I got a chart with the tap. It said 5mm drill for 6mm tap.

I have a 5mm thick steel bar and drilled a 5mm hole.

No problem tapping the thread but a bit shaky getting it started.
I had some camelia oil to help the cutting.

Then I drilled 10 holes.
Tapped 9 .........pretty straightforward. I am feelling pretty good about this metalwork gig.

Then SNAP or CRUNCH.
Almost finished the last hole and snapped the tap.
There was a bit poking out of the hole so I grabbed it with pliers. Not a good idea. It cracked off.
Tomorrow I will have another go at getting it out.
and buy another tap.

Having second thoughts about 3mm tap.

I would like a piece of steel about 10mm square. Does anyone have any suggestions about where I could buy some?

Thanks for all the step by steps jmk89. I tried to follow them. 90% success!

I have had some success and made a couple of bridges.

Once I took a little more care and patience, tapping the thread went fine.

The jobs are not pretty but the bridges work fine.

Here are a couple of pics. I'll put up better one when I get the boxes together.
The larger bridge has 6mm holes with tynes cut from an old hand saw. The bridge goes on a cajon that is on a stand.

The smaller bridge goes on a cajon with a hinged lid. The cajon doubles as a carry case for a seprewa. The bridge can be unscrewed and mounted inside the cajon for carrying about.