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: Accuracy of cheap ER collets|
I would only expect precision if the collet is a slide fit on the cutter shank; too much ( ie more than 1/2 mm) looseness is likely to reduce parallel gripping accuracy. Although ER collets have a greater gripping range than this it is not wise to make full use of this if it can be avoided. I have many cheap ER collets from ArcEuro and have found the accuracy to always be good Colin
|Thread: Adjustable Reamers|
If an adjustable reamer does not adjust easily or seems to have an oversize blade it almost certainly needs to be dismantled and cleaned with a degreaser. I was recently glad I had one to ream a very tight small end bush.
|Thread: Boiler Testing|
There should be no brass directly attached to the copper boiler and, yes, a bare boiler is required for the cold examination and the initial test at twice working pressure. It is likely the pressure gauge and obviously the safety valve(s) cannot be in place. Colin
|Thread: stainless boiler banding|
The cv boots on my car are secured with stainless steel ties, not sure of the size but must be around 3/16" and they are thin. So maybe they can be obtained from car spares factor. colin
|Thread: What Makes a Good Model Engineer?|
Patience: " I will make one of those one day" and 20 years later there it is. Colin
|Thread: Regrinding cross head screwdriver tips?|
There is a huge difference in the useful life between a properly hardened tip and a cheap one. Colin
|Thread: keyway on involute cutter|
I don't use keys for any of my 1" and 1.25" bore cutters and I've never had a problem but then I don't expect industrial production rates. However, I could forsee a problem if the cutter was fitted in a dirty state and then tightened itself altering the position when gear cutting. Colin
|Thread: measuring small bores|
I think you just need to ensure the boring tool is very sharp and that it is not rubbing below the cutting edge. The only practical way to measure small bores is to make a plug gauge , preferably with a small "nearly there" step. That's how I've done many such bearing fits.
|Thread: Benedict Cumberbatch featured on Cover of MEW 243|
Sometimes it is impossible or too fragile to make a casting to outside scale with internal space such as a gearbox and it is best to then fabricate by welding or machine from solid. This means there is a desire to make the fabrication look like a casting. I have recently done this for a model gearbox by leaving weld spatter all over it and had several people ask me how I made the casting. In this case weld ripples were smoothed, filled, attacked with a grinding wheel and painted aluminium colour.
|Thread: How accurately can you machine?|
The purpose of precision and associated tolerances is to make spare parts interchangeable and to ensure the tightness of fit is suitable for the assembly.
|Thread: Hot workshop|
I've got hazel trees partially shading my south facing workshop in the summer when they are in leaf and the sun is hottest and I still get any sunshine on offer in the winter when the leaves have fallen and it's most needed. When autumn arrives the local squirrels grab all the nuts before they ripen. In the winter I get a few replacement runner bean poles so if I can win the battle for some nuts it all works out to my advantage. At all times plenty of good daylight is welcome. I am very satisfied with a south facing workshop. Colin
|Thread: Material source needed|
Only a few days ago I made a hole saw from a roll pin to work on brass about 1/4" thick. I cut the teeth with a dremmel grinder by hand using a small grinding disk as accuracy is not important. It did the job much easier than I expected and was just as sharp when I finished.
|Thread: How to cool a piece for a shrink fit?|
In my opinion you are unlikely to get a big enough temperature difference by freezing the shaft. I would expect a difference of at least 200 degrees C . Colin
|Thread: Opening the gap...|
Quite right Michael, the gap piece should not be part of the structural strength, my old 7" centre height Drummond has a very usefull removable gap piece for doing bulky work on the faceplate and I've used it many times without problems on vintage car and motorbike repairs. Colin
If no great care was taken to ensure good clean finish when originally fitted there is not much chance of the gap piece being accurate after removal and refitting. Some of the imported machinery I've used shows such carelessness in other areas and I suppose that's inevitable at the price. Colin
|Thread: Tongue in cheek|
Interesting that the almost obsolete imperial system, being a binary progression, is more closely tied to digital computers and their components than the metric system replacing it is. Colin .
|Thread: Boiler tests comercial or club|
My club (Mid Sussex) is £20 a year. We get a workshop and boiler testing for this. Colin
|Thread: Vertex HV6 - Corrected Division Table plus universal dividing spreadsheet|
My Vertex dividing head chart (ratio 1:40) has a an error for 24t ,obviously a typo as it states 1 turn and 33/22 of a turn on a 33 hole dividing plate. You are going to spot the error though as it is impossible to do that. However, I no longer trust the printed charts without confirming the sums. Colin
|Thread: The Workshop Progress Thread (2016)|
Now and then I do a bit more on the 1.5" scale Burrell I started years ago. I do bits of this in between other projects. No castings used on this model.
|Thread: Use of domestic room as a workshop|
You need to change shoes when you enter or leave the room to avoid swarf being carried around the house by them. Been there done that. Curly swarf can be very difficult to remove from some carpets. Colin
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