Here is a list of all the postings Peter Maloney has made in our forums. Click on a thread name to jump to the thread.
|Thread: taper pins or roll pins|
Thanks for the replies guys. I will go down the roll pin route especially after reading about Simon's M3 grub screw. Going down the ENGINEER/FITTER road :- despite machining as accurately as possible I am finding that I am having to use lots of marking blue together with careful use of the needle files and a few thin shims to get things moving reasonably smoothly. This is my first loco (Pansy) so am not sure if this is normal or not.
Has anyone ever used roll pins instead of taper pins for a piston rod/ crosshead fixing. I already have some roll pins but not any taper pins or reamers.
My thoughts were leaning towards 'glue 'em in paint and all. Will try a few and see what happens. Nothing to loose after all.
A BIG MISTAKE PERHAPS?
Some time ago I made my Pansy footplates complete with holes for dummy rivets to be glued into place. I then sprayed them with grey car primer to prevent rust. I now want to glue the rivets in place. I can easily remove the paint from the flat surface but how on earth do I remove it from inside the holes? Any suggestions guys?
|Thread: Piston Packing|
Thanks for your help. Have reduced the interference and am about to make an adaptor if I can find a suitable sized piece of scrap.
How much interference should there be between graphite piston packing and a bore dia of 1.5in? Somewhere I read that 1/32nd in should be ok but it seems a bit excessive when lining up with the bore. I see that Julian Atkins suggests soaking in steam oil to make things easier. When fitted should the piston be moveable with hand pressure?
Been to Bristol ME exhibition today and there were 4 models of Pansy on show. Without exception they all used the 3 15/16 dimn to the start of the cab cutout and it looked perfect. That is the dimn I will be using.
Also, none of the bunkers had sharp corners - the rounded corners looked great. Must brush up my panel beating skills.
Sorry Guys - I should have typed 2 15/16 & 3 15/16.
If you draw out 2 15/16 dimn on sheet 9 (assuming your drawing is 1:1) it just does not look right to me. I have also looked at photos of full size locos for comparison.
Perhaps someone who has completed Pansy could advise.
If my sums are correct I have dropped ctrs by 9/16. This I believe brings the brake block pivot point in line with running position of wheel ctrs.
Also be aware that some Pansy info is given in LBSC's ways and means ME vol 118 issue 2973, ME vol118 issue 2978.
On sht 9 of drawings I believe the 2 5/16 dimn from bottom of cab should be 3 5/16. I have drawn this out and 2 5/16 does not look right. Hopefully there will be a Pansy on display at the Bristol ME exhibition later this month.
It's me again. Have you seen the discussion in the expansion link forum?
|Thread: Expansion LInks|
Thanks for the lively discussion.
My links are mild steel. I was going to case harden them. Do you think this is required in the light of your experience?
Out of interest I have been working on my Pansy on and off for 4 Years (more off than on). Not all holes are shown on drawings - the reversing bracket for example. I was lucky enough to have a full set of ME mags detailing construction and I sifted through these to find details of all extra holes to include at main frame drilling stage. They can be put in later but may involve a strip down of chassis.
The brake hanger holes should be 2in from bottom of frame. I had already put the 'wrong ones' into my frames before I found out.
In my album pics you may have noticed a 'funny frame stretcher' behind crank axle This is just temporary. The grey spray paint is just to protect against rust during construction.
There are quite a lot of other errors also. If you do a search on 'Pansy Errors' on Google you will find them.
Have you read all the posts in ME for Pansy? I was totally confused over variations in valve gear dimensions but Julian Atkins came to the rescue with a suggested correct design which I am following.
I don't feel that I should give you these details direct without Julian's approval. Hopefully he will see this post and come to your rescue also.
Just thought that I would add a few pics to my album showing progress on my first model. As you can see I have jumped about production depending on money, time and materials available.
You will see many temporary fixings in place. The holes in splashers are jig holes which need filling. Not too happy with square corners on bunker. Will probably remake when my panel beating skills improve.
|Thread: Expansion LInks|
I am still pondering over steel or bronze die blocks. After all, axles are steel with bronze axle boxes as are crank axles and big end bearings
Have created an album for photos so another success. The 'G clamps' are holding in place simple stops to limit swing travel in both directions. The pivot pin is a 'fitted bolt' and pin hole was drilled using the 4 Jaw and the cross slide traversed to give the require swing radius and locked in place. I also locked the saddle in place for each cut. A little time consuming but done to reduce vibration.
I too have thought about cylindrical die blocks but have been concerned about lack of surface area contact and subsequent increased wear. Do you use steel or bronze for the cylindrical die blocks? I suppose that with the relatively little use the models get, that the blocks will last some time. After all they would be easy to replace hopefully after a few years.
Will take some photos and try to work out how to post them.
My first attempt at this 'swinging bar ' method burnt out my cutter but for the next 2 all went well when I drilled a series of holes to remove the bulk of the material.
After several failures at drilling and filing my Pansy expansion links and now several months later, I have finally had another attempt.
Not having a rotary table or a milling spindle I resorted to swinging them by hand on a bar attached to an angle plate on cross slide with cutter in the 4 jaw.
With small cuts and steady movement on the bar I am very pleased with the result. OK they needed a little draw filing and polishing but the method seems to work. I am about to machine the links blocks by the same method with high expectations.
I spent a lot of time thinking and making the set-up but would like to think that I have learned a lot in the process.
|Thread: Hinge Straps|
Not directly related, but a good source of small hinges when cut up can be found on spec cases. Especially good for Pansy tool box hinges.
|Thread: OO Gauge loco|
I don't have any knowledge of the other books mentioned but if you can find a copy of the F.J.ROCHE book you will find 100 plans of locos, tenders and other details (chimneys, domes etc.).
Good luck in your search.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.