Two questions: What is the best way to remove the parts from the sprue? Razorsaw? How does the part detail get formed where the sprue is attached? Specifically on tires. I just got an Accurate Armour CRT(W) Fox and the wheels have rather large resin sprue attached to it. How does the tread pattern get left behind after removing the sprue?

I remove them Best as possible...... Then make sure they're at the bottom (if going in a Dio)

Hi Jeffrey i always tend to use a razor saw when removing casting gates from resin kits but smaller ones may be pared away with a sharp blade or even sanded away you will find the best technique for you! as for tyres and detasils that remain unharmed by this process thats due to a conciensious effort by the either the sculptor or caster when applying these blocks or "gates" to the peice before casting ,even they do a good job then details such as tyre treads will only have the block attatched to the raised portions and then the detials remain they fill the under cuts with either very thin plastic or film to ensure the mould doesnt totally encaspulate the master thus rendering it almost impossible to remove without cutting the mould ,
most of the time however you might need to re-work som of the details in .accurate armour is a very good company i have built a lot of thier kits and dont have much problems with them! good luck! and let us see some pictures of the finished peice!

Razor saw or dremel w/ cut off wheel. (depending on size and detail)
Then its up to you to rescribe the detail of the tread if it is not there. You can also position it 'down' so you don't have to worry about it.

there is no 100% way to get it all off perfectly, just do as best of a job as you can. Look at the piece first and see if there is any major detail that will be cut off and then work off that

I agree with the others when they say that's impossible to remove them perfectly. Being allergic myself to resin I try to reduce to the minimum the resin dust (that by the way it's quite dangerous on her own) so i never use saws or motor tools. What I do it's quite simple, I mark a few time with a sharp knife along the profile of the part to be removed on both sides and then, very gently I break the part off the casting support with the help of my hands or a flat noze plier. I find this method safer (in terms of healthcare), far a lot quicker because reduces significantly the amount of time I have to spend in sanding and in puttying (in case of mistakes).
Ciao