- Thread starter zzr1200
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zzr1200
Working at 650 ft on open steel work.
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Thanks for looking SD.
Its one of those things these days, metricification is pain in the backside. Its easier to get whitworth or bsf at times...
I've put them on "Watch"..... might even phone them tomorrow if I get time...
Shox Dr
Chief Engineer to Carlos Fandango
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1/2 UNF CSK Allen screw x 1.25" . They only have 3 in stock..I need 6 minimum...
And not at £2.99 each....well that how I read it....
Fleabay = Ripoff for nuts/bolts
UNF are high tensile, hence the price
Shox Dr
Chief Engineer to Carlos Fandango
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Just a thought, have a look on las web site. I’ve been pleasantly surprised at the cost of aero spec fasteners
https://www.lasaero.com/
Edit, just had a look, cant find csk, socket head
Edit (again), web site looks to be showing a limited selection. I’m back there Wednesday, [hopefully] I’ll remember to look in the catalog
https://www.lasaero.com/
Edit, just had a look, cant find csk, socket head
Edit (again), web site looks to be showing a limited selection. I’m back there Wednesday, [hopefully] I’ll remember to look in the catalog
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Give West Bromwich Fasteners a call.
zzr1200
Working at 650 ft on open steel work.
- Messages
- 5,799
- Location
- Glapwell, Chesterfield, Derbyshire, UK
High tensile is the material the fastener is made from not the thread pitch/thread spec, high tensile UNC are just as strong as UNF, it depends on the material strength in which the threads are tapped.
In aluminium I wouldn't use UNF, I'd use UNC because of parent material strength of the threaded part.
Metric threads are available in 8.8/10.9/12.9 and A2.
The reason CSK UNF screws are expensive is because very few people use them now and most suppliers dont stock them, its all gone metric now.
Shox Dr
Chief Engineer to Carlos Fandango
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- 17,993
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- East Yorkshire
You missunderstand what I was trying to say. UNF are ONLY available in high tensile (12.9). (At least that was what I was told by our local imperial guys, (they’ve gone now), their prices for imperial were no dearer than metric.
Parm
Respect The Sound System
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Just a curve ball here, but why do you need such high tensile strength bolts on a welding positioned build?
I was at a tower crane place investigating an accident and got shown round the yard
All tower cranes are bolted to a ground anchor set in concrete with either four or eight 60mm bolts roughly 200mm long. Tensile strength of 12.9. Only torqued up to 50% of bolts capacity. This is apparently more than enough, prevents stretching and allows bolts to be used again
I was at a tower crane place investigating an accident and got shown round the yard
All tower cranes are bolted to a ground anchor set in concrete with either four or eight 60mm bolts roughly 200mm long. Tensile strength of 12.9. Only torqued up to 50% of bolts capacity. This is apparently more than enough, prevents stretching and allows bolts to be used again
zzr1200
Working at 650 ft on open steel work.
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- 5,799
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- Glapwell, Chesterfield, Derbyshire, UK
The rotary table top needs to flat as possible in case I need to bolt/clamp an item to it I don't want to weld the table top to the main shaft in case I ever need to fabricate a special mount for it, so the only way is to use countersunk screws to secure it. I also have a 10 inch diameter 4 jaw chuck to mount to it as well.
Parm
Respect The Sound System
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Ok all good so far but why the specialist bolts, will metric countersink not do?
zzr1200
Working at 650 ft on open steel work.
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- 5,799
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- Glapwell, Chesterfield, Derbyshire, UK
The threaded holes in the flange (which is a salvaged machine hub) has 1/2" UNF threads for the wheel studs and I can be a stubborn old b**ger at times, it already has holes in it so why drill more, plus I just prefer things to be right if possible.
Parm
Respect The Sound System
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Ok that puts a bit more context to your situation. I’m like that some times
..... is it not easier to go metric next size up?
You seem have the technology and will certainly save you a wild goose chase
zzr1200
Working at 650 ft on open steel work.
- Messages
- 5,799
- Location
- Glapwell, Chesterfield, Derbyshire, UK
I don't consider that UNF CSK screw are specialist bolts, years ago you could get them without a problem, in many fastener supplier they were a stock item, its only over the past 10 years that imperial threads are now becoming non stock items and special order only.
slim_boy_fat
Forum Supporter
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Can't you fill then in and re-drill to a size of your choice, or at least to suit availability?
zzr1200
Working at 650 ft on open steel work.
- Messages
- 5,799
- Location
- Glapwell, Chesterfield, Derbyshire, UK
Can't you fill then in and re-drill to a size of your choice, or at least to suit availability?
I could do but the holes are there and threaded, so why not use them.
I know it may seem easier just to drill more holes and cut new threads but thats just me, metric threads come in course, fine and extra fine threads, try buying metric extra fine bolts...... A nightmare...
At some time in the future very thing will be glued together, there won't be threads as such no bolts/nuts just glue, possibly not even welding..
What will we all do then?
Anyway I'll have to order some soon.
