cutting gaskets
Mike Brett | 18/09/2016 12:33:15 |
129 forum posts 18 photos | Hi I am trying to cut some small intricate gaskets for a steam engine. The material I have at present I got of E-Bay , it is of a bluish colour about 0.50 mm thick. Trouble is it is so fragile , trying to put the gasket over studs and it just falls apart. Is there a stronger material brand on the market that anyone could recommend. Cheers Mike |
not done it yet | 18/09/2016 14:39:57 |
7517 forum posts 20 photos | Lay gasket on face and then fit the studs? Standard A4 paper is about 0.1mm, so about the thickness of 5 sheets of paper?
I've no suggestions for an alternative. Try another internet source might be a possibility - epay quality is not always good quality.
What size are we talking here? Small, for me, is less than 50mm |
Mike Brett | 18/09/2016 15:06:00 |
129 forum posts 18 photos | Good idea about fitting gasket then studs, unfortunately I have already fitted studs with loctite . Gasket is 8 mm wide with 4 mm holes for studs, not much either side of studs. Mike
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DMB | 18/09/2016 15:19:51 |
1585 forum posts 1 photos | What about clamping the already drilled steam chest to a block of wood with gasket sandwiched between and poke drill through? Just a thought. John |
duncan webster | 18/09/2016 15:46:11 |
5307 forum posts 83 photos | Are you trying to punch holes for the studs, or just fit a gasket with holes already in it? |
John Hinkley | 18/09/2016 17:46:04 |
![]() 1545 forum posts 484 photos | First, let me say that I know diddly squat about steam engines, but if I had to do what you are trying to acheive, I think I would lightly fix the gasket to whatever goes over the studs and fit it that way. (Kind of like a cylinder head sliding over the studs in an IC engine block. ) By definition, the fitting, valve chest cover or whatever, doesn't have any protuberences to get in the way. Or have I got hold of the wrong end of the stick? Alternatively, use a thicker material or gasket goo in a tube. Good luck. John
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not done it yet | 18/09/2016 18:08:41 |
7517 forum posts 20 photos | One thought - are the stud ends at the same dimensions as at the root ie, exact same pattern.
Another is to make the gasket as a larger sheet and trim to size after fixing. Edited By not done it yet on 18/09/2016 18:10:59 |
Mike Brett | 18/09/2016 19:28:05 |
129 forum posts 18 photos | Many thanks for all your replies. I had already drilled the gasket, it was getting it over the studs that was the problem. The best solution I can see from the replies is to fit as a complete sheet and cut to size after, why did I not think of that. If that fails I have seen gasket material made of nitril, not sure if this is steam proof though. Mike |
JasonB | 18/09/2016 19:36:16 |
![]() 25215 forum posts 3105 photos 1 articles | Liquid gasket works for me. Teflon baking sheet works for others You say that you drilled the stud holes in teh gasket? this may well leave a ragged edge which won't help with tearing, they are better punched out either with a Wad (hollow) punch or a punch and die (4mm peg and 4mm hole in die) Edited By JasonB on 18/09/2016 19:39:10 |
Howi | 19/09/2016 09:01:25 |
![]() 442 forum posts 19 photos | Teflon baking sheets as has been suggested, silicone sealer etc. For cutting stud holes I would suggest getting hold of a radio telescopic aerial, cut the end off and hey ho you have a series of hole cutters, just sharpen the inside of the base of each tube and a simple twisting action cuts a perfect hole with no tearing as you would with a drill. |
Neil Wyatt | 19/09/2016 09:17:31 |
![]() 19226 forum posts 749 photos 86 articles | Gasket holes shouldn't be a tight fit to the studs, you need to be sure they don't get damaged edges or crinkles. |
not done it yet | 19/09/2016 09:25:39 |
7517 forum posts 20 photos | In addition to Neil's comment, the studs can be waisted slightly. Not an easy solution if they are already permanently affixed. Just depends on the strength of the material and the designed working forces. The threads are likely the limiting factor, rather than the cross sectional area? |
Ian S C | 19/09/2016 10:55:58 |
![]() 7468 forum posts 230 photos | To cut the holes, lay the gasket paper on the part with the drilled holes, find one of the holes through the paper then using a ball bearing a bit bigger than the hole, put this on the hole and give it a whack, first hole, put a peg in the hole through the paper, and do the same for the next hole, put in another peg, carry on and do the rest, then tap around the edge of the casting or what ever, and the sharp edge will cut the gasket. Some bit might need cutting, but often the whole gasket can be made this way. Ian S C |
Trevorh | 19/09/2016 11:08:28 |
![]() 316 forum posts 89 photos | Try using a Paper Drill Bit - gives a perfect hole in most soft materials google paper drill bits cheers Trevor |
Lambton | 19/09/2016 11:42:16 |
![]() 694 forum posts 2 photos | Mike, Try They sell plain gasket paper as follows. "Suitable for mineral oils, hydrocarbons and cold water not suitable for acids and steam. Maximum temperature 120'C Available in 0.25mm, 0.5mm, 0.8mm and 1mm thick all from 1 metre wide rolls". For cutting holes I use a revolving leather punch e.g. Clarke CHT489 about £8 from Machine Mart. It has punches 2,2.5,3,3.5,4 & 4.5 mm diameter. For larger hole I use wad punches. I hope this is of help.
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duncan webster | 19/09/2016 11:55:03 |
5307 forum posts 83 photos | Posted by JasonB on 18/09/2016 19:36:16:
Liquid gasket works for me. Teflon baking sheet works for others You say that you drilled the stud holes in teh gasket? this may well leave a ragged edge which won't help with tearing, they are better punched out either with a Wad (hollow) punch or a punch and die (4mm peg and 4mm hole in die) Edited By JasonB on 18/09/2016 19:39:10 +1 for punch and die, they don't need to be hardened, in your case make die cylindrical, 7mm OD, 4mm hole, hold it in drilling vice, grind the non cutting end of a 4mm drill so it has sharp corners, then fit the gasket to the cover and use it to position the holes, poking the punch through the holes in the cover Edited By duncan webster on 19/09/2016 11:55:18 |
Brian Wood | 19/09/2016 14:10:53 |
2742 forum posts 39 photos | Mike, Regards |
duncan webster | 19/09/2016 16:50:29 |
5307 forum posts 83 photos | Is this **LINK** the ptfe sheet people are referring to? |
Tim Stevens | 19/09/2016 18:05:15 |
![]() 1779 forum posts 1 photos | Surely the right name for a firm selling gasket paper to model engineers, is 'Stationary stationery' ? Tim |
John Stevenson | 19/09/2016 19:21:08 |
![]() 5068 forum posts 3 photos | Know anyone who has a laser ? A lot of maker types have them.
Brilliant at gaskets.
The hole in the middle is 1mm, the hole towards the outer edge as is the annular slot are both 1/2mm. 14 seconds to cut this and can cut as many as I want with same accuracy. |
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