Tap and Die. What size handle do I need for a 1¼" BSP tap.

Pipeydick said:
Just use an adjustable spanner,i,ve been a pipefitter for over 50yrs and on the rare occasion where a tap is reqd that's all i've used, just make sure you keep it square to the hole and use plenty of oil
Click to expand...
likewise.. (y)
 
ok. I have a plan.

I am going to buy a 1" to 1/2" adapter.
1714143609625.png


And a small drill press thingy. not really a drill press but.
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The plan would be to clamp this to the sheet. Lower the head so the tap is in contact with the hole. Then use a ratchet on the top to slowly drive it in. Obviously reversing to clear swarf as per normal tapping.
This will allow me to keep it straight/parallel/90° to the material while applying a reasonable amount of pressure and turning.

I was thinking about a drill press but for some of the holes that are more central to a sheet I wouldn't be able to get it under the drill enough.

I will probably screw this to a sheet of MDF to allow me to clamp at the edges.

Just an initial thought/plan. Might not work but worth a go.
 
Possibly won't even need to clamp it down.
 
Well that plan failed at the first hurdle. The tap didn't fit into the adapter and the stand I ended up ordering had a round drive rather than the hex one in the image. So they got returned today.
I decided to do some measuring of my existing handles and extrapolate to what size I would need.
While then searching for M32-M42 handles (I still wasn't sure) I found these on Ebay.

www.ebay.co.uk

BAR TYPE TAP WRENCH Small-Large ADJUSTABLE Vehicle Threading Tool Holder Handle | eBay

Top quality tools for hand tapping operations. Long Handles give greater leverage. Hardened and tempered jaw. Notice: Oil on tool to prevent it from rusting before receiving the product.
www.ebay.co.uk

So. 1½" tap handle ordered. Should easily handle my 1¼" tap :D

Another £54 into this project.
 
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Gromett said:
Well that plan failed at the first hurdle. The tap didn't fit into the adapter and the stand I ended up ordering had a round drive rather than the hex one in the image. So they got returned today.
I decided to do some measuring of my existing handles and extrapolate to what size I would need.
While then searching for M32-M42 handles (I still wasn't sure) I found these on Ebay.

www.ebay.co.uk

BAR TYPE TAP WRENCH Small-Large ADJUSTABLE Vehicle Threading Tool Holder Handle | eBay

Top quality tools for hand tapping operations. Long Handles give greater leverage. Hardened and tempered jaw. Notice: Oil on tool to prevent it from rusting before receiving the product.
www.ebay.co.uk

So. 1½" tap handle ordered. Should easily handle my 1¼" tap :D

Another £54 into this project.
Click to expand...

Have you not got a spanner that fits the tap.

You could have made a tap spanner from a piece of ply 😉😊
 
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Silver-Fox said:
Have you not got a spanner that fits the tap.

You could have made a tap spanner from a piece of ply 😉😊
Click to expand...
A spanner would not do the job. I need to be able to hold it square and level.

I am not half arsing this. I want to be able to do an excellent job and probably doing LOTS of these each year. Worth the investment.

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Gromett said:
A spanner would not do the job. I need to be able to hold it square and level.

I am not half arsing this. I want to be able to do an excellent job and probably doing LOTS of these each year. Worth the investment.
Click to expand...
Machine up an adaptor for it to fit your pillar drill and run it in by hand or using a chain strap around the chuck? That'd also help you keep it vertically true as with a big handle the bars are longer so more leverage to get out of true.
 
Get yourself a short piece of round bar machined up with a 42mm hole in it and use that to guide the tap squarely into the job.
 
Burgo said:
Machine up an adaptor for it to fit your pillar drill and run it in by hand or using a chain strap around the chuck? That'd also help you keep it vertically true as with a big handle the bars are longer so more leverage to get out of true.
Click to expand...
Can't use a pillar drill as the sheets of plastic may be too big to fit under one. Needs a universal solution.
 
jockaneezer said:
Get yourself a short piece of round bar machined up with a 42mm hole in it and use that to guide the tap squarely into the job.
Click to expand...
Got some small corner blocks already on order.

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I have the handle ordered and I have designed a jig which might possibly work. Will be an interesting engineering project :)
Can't wait for next week when the plastic sheets arrive.
 
I ordered a 1 ½" tap handle and it just arrived. What a beast. But my 1¼" tap wouldn't fit properly.

1715176749669.png

It wouldn't fit in straight and is canted over. and wobbles even when tightened down.

I then measured it and

Yup, they sent me a 1¼" tap handle. One thing after another.

1715176834825.png
 
Jeez, that's a rough looking wrench for £54, I'm not surprised it's wobbling, but I've just looked on eBay and I can see why you're struggling to get a decent one !
Is there anyone down your way that could profile you (plasma, laser, or water jet) one out of a piece of plate just to suit that one tap ?
 
Use 2 lengths of angle iron, 2 holes in one end , spaced to clear tap square and bolt them around tap
1715193666752.png

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jockaneezer said:
Jeez, that's a rough looking wrench for £54, I'm not surprised it's wobbling, but I've just looked on eBay and I can see why you're struggling to get a decent one !
Is there anyone down your way that could profile you (plasma, laser, or water jet) one out of a piece of plate just to suit that one tap ?
Click to expand...
It;s wobbling because I can't get the tap to fit how it is supposed to. If It was 2mm wider it would be perfect.

Try finding a 1½" tap wrench at anything under £150 :p

They sent me a 1¼" ...
 
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Gromett said:
I am not half arsing this. I want to be able to do an excellent job and probably doing LOTS of these each year. Worth the investment.
Click to expand...

That being the case buy yourself a pillar drill and a running centre to put in it.

You can hold the the tap square with the work using the centre 😊
 
A pillar drill was mentioned earlier, but he doubted there would be enough "throat" to accommodate his workpiece ?

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Silver-Fox said:
That being the case buy yourself a pillar drill and a running centre to put in it.

You can hold the the tap square with the work using the centre 😊
Click to expand...
That is the way I am heading now.

The plan has now changed. Initially I was going to be welding the insert into the plastic tank before tapping and in some cases this would prevent it fitting into a pillar drill.
The reason for this is the inserts are too thin to clamp and would probably blow if not in situ.

however, I have now designed a jig that will hold the insert in a vice. So I could use a pillar drill.

However buying a pillar drill for a couple of hundred is out of budget for a few weeks.

The smaller tap also doesn't have the hole to put a centre in.

jockaneezer said:
A pillar drill was mentioned earlier, but he doubted there would be enough "throat" to accommodate his workpiece ?
Click to expand...
Correct but the plan "may" have changed. I won't know till tomorrow when I get the inserts if my jig idea will work.

But in the meantime I am talking to the seller about getting what I paid for.
 
Also seems a bit overkill spending over £100 on a drill just to hold a tap vertical lol. Oh well.
 
CNC inserts have arrived and they are very good :)

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Here is one of each separated out. Very hard to get a decent picture of something that is all black.

1715252049684.png


Once the tap is made through the centre, ½" BSP and 1¼" BSP I will drill a hole in the tank, insert the insert and weld both inside the tank and outside the tank.

These inserts a more expensive than the commercial ones but are a lot more solid by the looks of things. Going to stand up to a lot of abuse even underneath a vehicle when used for grey tanks.
Very happy. Just got to get the tapping situation under control now.
 

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