Here is a list of all the postings colin hawes has made in our forums. Click on a thread name to jump to the thread.
|Thread: Double thread T- nuts|
Make sure you can get a longer nut into the T slot! There is not enough space on my minimill.
|Thread: Another broken tap thread|
Has anyone tried to grind out a broken tap with a Dremmel-type grinder?This tap seems big enough; at least it could produce a dimple to start acarbide drill.Before we had carbide drills stellite was used to drill through any hard steel even hss.
|Thread: Stress relieve in castings.|
I can remember castings being left outside to rust .I was told that this was to stress relieve them by virtue of the rust eating away at the hard skin.Not much use to us though; they had to be left for several years for a good result! It seems that embedded sand was also removed by this process.
On second thoughts I have taken so long on one project it might have been a good idea!
Edited By colin hawes on 25/01/2012 13:26:50
|Thread: Making your own case hardening compound.|
I have had great success using charcoal from a bonfire and slivers of leather from an old belt to case harden a roller bearing race for an ancient vehicle. The part was packed in a tobacco tin and sealed with yellow clay from my garden. It is important to seal the tin. I can't remember how long the tin was kept at red heat but I got a deep enough case to grind the part in my lathe after hardening.
|Thread: Is it just me|
I've got so many scrapped things I can't bear to get rid of that I forget what I've got and go and buy one!! £!x%!!!. It hurts.
|Thread: Reamers - hand vs MT|
Reamers are intended to produce a very close tolerance hole and are most likely to do this if allowed to float a little, to follow the drilled hole, by holding them the minimal amount in the drill chuck.Reamers with a taper shank are more likely to have a tendency to bore the hole due to inaccuracy in a tailstock.
|Thread: Slitting saw thickness|
Rigid workholding is of utmost importance. Vibration can easily come from a flimsy setup.
|Thread: MEW, would less be more?|
Never be negative about things. I am happy to read more than one mag. a day ,it,s just a case of prioritising things.Read the bits of immediate interest for motivation ,get out to the workshop if you can afford to heat it, but read the mags. when you have just scrapped the latest part or lost that tiny bit that you have just parted off.Above all, try to get something done each day. The longest journey and little steps!
|Thread: Drilling deep holes - 10x drill diameter - Runout?|
Using a slot drill to correct concentricity of the pilot hole will improve the chances of a larger drill to correct any initial inaccuracy as it will then be guided by it's diameter rather than it's point or pilot hole.
|Thread: Flat bottom holes|
Tony please note that slot drills are not ftat on the end but relieved to their centre to aid their guidance.To get a flat bottomed hole means regrinding a slot drill's end.
|Thread: Fly Cutting|
Hi Steve, I agree with the previous comments and would like to add that the workpiece needs to be well suported underneath by packing if it is not flat. Vibration is the problem.
|Thread: Bore and stroke ratio in steam engine.|
Work done by a steam engine is (pressure) x (area of piston face) x (distance the piston travels) . An early cut off allows the expanding steam to be used more efficiently due to greater pressure drop at end of stroke,so I would expect a longer stroke to make better use of the available steam but at lower rpm.
|Thread: Knurling Help Needed|
I agree with Kwil knurls work best on soft steels.
|Thread: Screw cutting gears|
I don't have a Myford lathe but I would like to advise that on most imperial lathes you need to keep the leadscrew engaged and reverse the motor to return to your thread start when cutting metric threads as it won't pick up the thread again if you try to use the thread indicator.
My scribers are made of 6ins of 1/8 silver steel,ofhand sharpened,1in bent to 30 deg. and hardened at both ends. I have never found a need for a truly central point.
|Thread: How to create a circular scribe|
I very rarely mark anything out but use the lathe or mill to locate holes.This eliminates human error due to eyesight but needs care with sums.I have made 24 equally spaced vee slots on the lathechuck backplate and can index from this,using a small milling spindle to centre drill the holes.
|Thread: Did you make one of these at school or as an apprentice?|
When I was doing metalwork at school and later at a technical college we had to do things like file a square hole to a gauge size and make a square plug to fit it, all in thick steel sheet.We never made anything as interesting as an engine, although we did do beaten copper work which gave me some confidence in boiler making.
|Thread: PeterE - C3 accessories - Tool Tray|
Safety first.Just make sure you get into the habit of taking tools from the side and not across the chuck,one day you may leave the machine running and drop the drill chuck key.I have a tray on the front of the headstock and sometimes let my old flat belt lathe warm up while setting tools.This may be a bad habit but time is precious.
|Thread: thread indicator|
I have made one for my old 7 inch drummond lathe and used it on very many occasions over many years.
|Thread: Making wheels by casting in the spokes|
Excellent video set Jason. Thanks, I enjoyed watching.
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