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+--- Thread: Match-plate pattern (/thread-4349.html)
Match-plate pattern - Pete O - 09-21-2021
New street number for my new mailbox. I'm planning on casting this in brass so I can give a nice polished finish to the face of the numbers but I'll do a test run in aluminium, which will enable me to weigh it and see if I have enough brass on hand as well as seeing how the pattern works out. A match-plate seemed the best solution to get the numbers spaced and aligned, I wanted it to be one piece rather than singles. Took a while to get to this stage.
[attachment=17315]
[attachment=17316]
RE: Match-plate pattern - Pete O - 10-07-2021
Only those who have spent weeks preparing and days executing the creation of something that could probably be bought at the hardware for twenty bucks, will understand how good it felt to see this come out of the sand yesterday.
[attachment=17339]
It took so many attempts to get the pattern to pull cleanly from the sand that I abandoned the idea of pouring a test piece in ally first. I had a few attempts last week and could not get a clean separation from the sand; spent some more time on the pattern fine-tuning fillets in plasticine. Spent several hours on Wednesday this week ramming, mulling, ramming, mulling, finally got a clean separation and then poured short!!
I must have learned from the experience though, yesterday I applied all the lessons I had learned and got a beautiful clean mould on the first attempt
[attachment=17340]
I scoured the shed for every last piece of brass scrap. Chrome-plated and enamelled bathroom fittings, old irrigation valves, the amount of dross was appalling! The A6 crucible was brim-full and only just filled the mould. For size reference, that's a cut-down 205 litre (44 gallon) drum that I have broken the mould out in.
Fettling and polishing next week.
