Thread: Trying to make a QCTP anchor bolt

Another option would be to drill out the centre of a suitable 12 mm bolt thread of correct length to 8 mm, Then turn down the plain end of your 10 mm bolt to the same diameter. Then manganese bronze braze the two together using MAPP gas (or oxy if you have it).

If you do go this way be sure to wet (tin) both surfaces with bronze and push together when hot for complete coverage/bond.

Remember that the thinner the bronze join, the stronger the bond.

Cheers Rob

just on your choice of material.

Why a HIGH tensile bolt rather than use a standard mild steel bolt, or steel rod?

Leaving aside issues of machineability, a high tensile bolt is not designed to be used as a "post"

Originally Posted by ian

Why a HIGH tensile bolt rather than use a standard mild steel bolt, or steel rod?

Hi Ian,

I was just trying to use material that was readily available to me. Bunnings seems to only stock bolts that are either stainless steel, hot dipped galvanised, some other weird tech coated bling, or this stuff (high tensile zinc coated). I chose what I thought was the lesser of the evils. Alas, they are all evil it seems.

Now I'll have to try to find 12L14 steel rod from somewhere. You'd think that would be easy in Sydney (Australia's largest city) but I have heard that sourcing stock in Australia is almost as difficult as finding a decent lathe unless you have deep pockets.

Cheers,
Andrew

Hi Rob (xynudu?),

I don't have any brazing equipment or skills yet. Still a baby, but I'll get there one day

Cheers,
Andrew.

Hi Dave J,

I didn't know what a helicoil was until you mentioned it, so no I haven't thought about it . Where would I get it and would it matter that the M10 is 1.5 pitch and the M12 is 1.75 pitch?

Cheers,
Andrew

Andrew,
I'm happy to make this stud and send it to you if you don't mind waiting a week.

Originally Posted by jack620

Andrew,
I'm happy to make this stud and send it to you if you don't mind waiting a week.

Thanks Chris, you're very kind, but I'm treating it as a training exercise so I'll see how I go

eBay is easy for me to buy anything lol, there usually suited to the next size down thread so you should be right, check the specs on them in the description, or Google them

Originally Posted by simplicio

Hi Dave J,

I didn't know what a helicoil was until you mentioned it, so no I haven't thought about it . Where would I get it and would it matter that the M10 is 1.5 pitch and the M12 is 1.75 pitch?

Cheers,
Andrew

Originally Posted by simplicio

Hi Rob (xynudu?),

I don't have any brazing equipment or skills yet. Still a baby, but I'll get there one day

Cheers,
Andrew.

Hi Andrew,

We all start at the beginning and progress. It's a continual learning curve and all options are on the table.

Certainly bronze brazing is an old skill sadly neglected/overlooked by most machinists. After all why would any one want to braze when they can MIG, TIG and stick weld

Cheers Rob (Xynudu)

Originally Posted by simplicio

Now I'll have to try to find 12L14 steel rod from somewhere.
Cheers,
Andrew

Edcon Steel https://www.edconsteel.com.au/ stock 1214 free machining steel. 1 meter of 12.7mm dia will cost you under $10.00 including the cutting charge.

Graham.