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Hi guysI have another silly question which might be obvious to everybody except myself. Bear in mind that when I started this hobby I did not have an engineering or machining background.Today I was drilling the clearance holes in the rear cylinder cover of the Corliss and was thinking of what type of fastening I should use for this model. Studs or bolts. I am sort of leaning on using studs but the last time I tried using homemade studs (on the Kiwi) the experience was not positive. I could not line up the two halves of the Kiwi crankcase with my studs. When I used threaded rod instead I had no problem at all to line them up.Which brings me to my question which portrays my level of ignorance. What should be the clearance hole for a 3mm stud??I have always assumed it to be 3mm but now I am having doubts about it.RegardsVince
Or you could clamp the parts together and and drill tapping size through the cover into cylinder, then open out the holes in the cylinder cover to clearance size. Don't forget to mark the cylinder cover if necessary so it goes back in the same orientation. Also, don't make the (easy) mistake of drilling clearance size into the cylinder Simon
Other than historical accuracy, why would threaded rod be "frowned upon?"Will the stud police show up with a search warrant?"Sir, keep your hands where we can see them and remove that cylinder head."
I hate it when you buy a bolt and it is threaded the entire length of its shank. Where did these people come from? A bolt should only be threaded for 2 1/2 times the diameter of the bolt, the plain part of the shank is there for a good reason
I think most people buy the screws and cut them to the length required which if it were a bolt may remove too much thread.
Hi Guys - just like to clarify why I said to drill the clearance holes first - in effect spotting the hole for the tapping drill. It is always good practice to take out the top thread of any tapped hole. It is much better to do this before tapping as if done afterward that small countersink, for that's what it is, will follow the thread and go eccentric. Taking out that first thread definitely makes the tapping easier and subsequently aids inserting the bolts later especially if they are in awkward to get at places.
Secondly and probably far more important, if opening out pre drilled tapping holes, particularly on brass or bronze there's a very good possibility that the part will snatch and pull up the drill if this op is carried out on the drill press, which in all probablilty it will be if tackling it this way. It wouldn't be the first time a tapped hole has been ruined in this fashion that's for sure - yes, you can stone the drill cutting edges but why do that only to have to resharpen.
When spotting through like this if the drill depth stop is set not only will the spotting depth be consistent but the tapping drill will centre nicely too - it can then be drilled to depth without fear of a mishap.Only passing on a lifetimes habit - that's not to infer anyone else's method is wrong.Good luck Vince however you go about it.Regards - Ramon
the first bit of thread is not to full depth.
Quote from: Jasonb on January 07, 2014, 08:37:35 PMI think most people buy the screws and cut them to the length required which if it were a bolt may remove too much thread. You might as well use threaded rod Jo
Marv"Anality" has now been officially added to the MEM lexicon.
Quote from: sshire on January 07, 2014, 08:28:17 PM Marv"Anality" has now been officially added to the MEM lexicon. I'm flattered. Even more so now that your research reveals that anality is a genuine word found in several dictionaries. I had no idea.Nevertheless, the success of this word-coining has emboldened me. Given the opportunities afforded by this forum, I'm sure I can come up with some really stunning additions to the local lexicon.
Ever since my teens, I've hated studs - the thread on the exhaust studs on for instance a Puch mopeds always disappeared after a few years
Blame the material, not the stud! Make a set out of stainless or bronze and they will last forever and a bit.