If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.
Hi Neil
This whole project is so interesting. Your determination does you credit. Simon T would have loved to have seen this through to the end. I'm another with fingers crossed.
Jim
Thanks very much everyone for your interest and crossing your fingers, I felt the love- honestly!
I can happily report a (mostly) successful mould.
My first impressions were concerning, however, as there were loads of tiny bubbles in the top surface, and when I (eventually) got it out of the mould box, there are bubbles all through the mould. I worry that there will be bubbles evident on the surface of the casting.We shall see.
My smug trick of tapering the mould box was bo**ocks, because the texture of the 3D-print prevented the rubber from simply sliding out. :rolling: The point was to be able to put the mould back in its box to keep it closed accurately when pouring the resin.
I got it out eventually but I have now cut the box down one side to make it easier...
I cut the rubber carefully to release the figure, trying not to actually touch the pattern in case it's gone wrong and I have to do the mould again. Between the legs('Steady the Buffs...!') and up the back,. I did the same for the arms.
So far so good, I only broke his stumpy left hand and a small bit of one foot in the process- but amazingly not ONE finger of the right hand!
Next comes the resin.
This has the potential for disaster because my resin is quite old(2 years, 'borrowed' from work) and I know it has a shelf-life, so it might not go off at all.
Anyway, this was even more messy than the rubber. God, this casting is a black art!
Ultimately , I think the issue was more with my technique (or lack of) rather than the shelf-life of the resin....
A bad workman blames his tools but I'm sure that if I had a vacuum de-gasser there would be less problems of getting the resin into the mould. That said, I have designed the moulding plugs with current technology in mind; remember the early resin stuff, with huge great blocks of resin to cut off?
I did rush things because I was paranoid about the fast curing time of the resin, so I will take more time- over the head especially-next time and hope I can at least nail that. We will see better when I get some paint on him, but it does seem like the bubbles in the rubber haven't transmitted to the surface of the casting, so that's a plus.
I don't need a commercially faultless casting for the purposes of this exercise, but it would be good to minimise the amount of remedial work I need to do.
Stay tuned folks, for the next nail-biting installment !
cheers
Neil
Hi Neil
That casting doesn't look too bad. You seem to have all the detail there and the problem areas like around the waist and the jacket hem look fine.
I have done a little, very simple resin casting under the guidance of Simon. His main tips were to stir the rubber very gently to avoid bubbles. Pour carefully for the same reason. Pour only a bit of rubber at first and move the mould case around to coat the master. Work the rubber into potential air traps with a cocktail stick. Then top up.
Because of the short working time of the resin its a case of stirring and pouring gently without hanging about. Gently flex the mould and tap it firmly on the bench to dislodge air bubbles.
I'm sure you know all this so forgive me if I come over as "teaching grannie to suck eggs"
Looking forward to the next 'nail-biting installment' :thumb2:
Jim
Hi Neil
That casting doesn't look too bad. You seem to have all the detail there and the problem areas like around the waist and the jacket hem look fine.
I have done a little, very simple resin casting under the guidance of Simon. His main tips were to stir the rubber very gently to avoid bubbles. Pour carefully for the same reason. Pour only a bit of rubber at first and move the mould case around to coat the master. Work the rubber into potential air traps with a cocktail stick. Then top up.
Because of the short working time of the resin its a case of stirring and pouring gently without hanging about. Gently flex the mould and tap it firmly on the bench to dislodge air bubbles.
I'm sure you know all this so forgive me if I come over as "teaching grannie to suck eggs"
Looking forward to the next 'nail-biting installment' :thumb2:
Jim
Many thanks Jim
No worries- Granny has clearly forgotten how to suck those eggs! Thanks for jogging the geriatric memory.
I've just poured one but only the figure, not the arms this time. I think I tried to be too efficient by making one mould when it would have been better(and used less rubber) to make a separate one for the arms; so I will do them later , with full concentration.
The trouble is the amounts of resin are so small, you get a LOT of wastage in the mixing.
Wow and wow Neil, that's quite exciting stuff. Results look good, so well-done you .
Reading Jims and your description of moulding think I shall defer for the moment !
Wow and wow Neil, that's quite exciting stuff. Results look good, so well-done you .
Reading Jims and your description of moulding think I shall defer for the moment !
Thank you kindly ,John.
Yes it's quite frustrating; mind you, this is not exactly unambitious......there are easier things to mould and cast.
Somebody mentioned dogged determination earlier on, well I think this is going to drain my reserves....
I thought all except the head on this one was usable until I looked at the pic
and with that in mind I tried casting just the head, with the mould tilted to encourage the bubbles away from the nose and chin
Close, but no cigar.
So, to paraphrase Strictly-
Keeeeeeep casting!
I promise not to show any more failures after this as it's going to get tedious, but there might be a bit of a wait until my next post.......
cheers
Neil
Neil, I've bought far worse from 'reputable' suppliers, so I think that's a good first attempt. Seems that getting the air out can be a bit of a headache - why is it bubbles an pin-holes always occur in the worst possible places? Rather you than me, but I know you'll sort it out.
Neil, I've bought far worse from 'reputable' suppliers, so I think that's a good first attempt. Seems that getting the air out can be a bit of a headache - why is it bubbles an pin-holes always occur in the worst possible places? Rather you than me, but I know you'll sort it out.
I am happy to report that after 5 attempts I eventually achieved a decent casting!
Here is the rogues' gallery of failure
The decent one is not perfect but it will do. I had a lot of bubbles to fill and a few warts to remove -and I found more once I started painting- but I've finally started painting
So he should be done in time for the end of the GB-just...
Thanks for looking
Neil
Comment